BACKGROUND Lactose intolerance(LI)is commonly seen in East Asian countries.Several studies showed that lactose or milk loading has been used as a treatment for lactose malabsorption(LM)in Western countries,but there h...BACKGROUND Lactose intolerance(LI)is commonly seen in East Asian countries.Several studies showed that lactose or milk loading has been used as a treatment for lactose malabsorption(LM)in Western countries,but there have been no reports regarding this type of treatment in Japan.As lactose or milk loading requires ingestion of large amounts of lactose within a short period,this is considered to be too harsh for Japanese people because of their less habitual milk consumption(175 mL per day in average)than Western people.In this study,we demonstrated lactose tolerance acquisition in a suitable way for Japanese.AIM To examine the efficacy of lactose(cow’s milk)loading treatment in patients with LM.METHODS Individuals with abdominal symptoms induced by milk or dairy products(LI symptoms)were identified with a questionnaire.A 20 g lactose hydrogen breath test(LHBT)was carried out to confirm LM diagnosis and to evaluate co-existence of small intestinal bacterial overgrowth(SIBO).Respondents diagnosed with LM were selected as study subjects and were treated with incremental loads of cow’s milk,starting from 30 mL and increasing up to 200 mL at 4-7 d intervals.After the treatment,changes in symptoms and LM diagnostic value of 20 g LHBT were investigated.Stool samples pre-and post-treatment were examined for changes in intestinal microbiota using 16S rRNA sequencing.Informed consent was obtained prior to each stage of the study.RESULTS In 46 subjects with LI symptoms(10-68 years old,mean age 34 years old)identified with the questionnaire,35(76.1%)were diagnosed with LM by 20 g LHBT,and 6 had co-existing SIBO.The treatment with incremental cow’s milk was carried out in 32 subjects diagnosed with LM(14-68 years old,median age 38.5 years old).The mean period of the treatment was 41±8.6 d.Improvement of symptoms was observed in 29(90.6%;95%confidence interval:75.0%-98.0%)subjects.Although 20 g LHBT indicated that 10(34.5%)subjects had improved diagnostic value of LM,no change was observed in 16(55.2%)subjects.Analysis of the fecal intestinal microbiota showed a significant increase in Blautia in 7 subjects who became symptom-free after the treatment(P=0.0313).CONCLUSION LM was diagnosed in approximately 75%of the subjects who had LI.Incremental loads of cow’s milk is regarded as a useful treatment for LM without affecting everyday life.展开更多
Lactose plays a crucial role in the growth performance of pigs at weaning because it is a palatable and easily digestible energy source that eases the transition from milk to solid feed.However,the digestibility of la...Lactose plays a crucial role in the growth performance of pigs at weaning because it is a palatable and easily digestible energy source that eases the transition from milk to solid feed.However,the digestibility of lactose declines after weaning due to a reduction in endogenous lactase activity in piglets.As a result,some lactose may be fermented in the gastrointestinal tract of pigs.Fermentation of lactose by intestinal microbiota yields lactic acid and volatile fatty acids,which may positively regulate the intestinal environment and microbiome,resulting in improved gastrointestinal health of weanling pigs.We hypothesize that the prebiotic effect of lactose may play a larger role in weanling pig nutrition as the global feed industry strives to reduce antibiotic usage and pharmacological levels of zinc oxide and supra-nutritional levels of copper.Evidence presented in this review indicates that high dietary lactose improves growth performance of piglets,as well as the growth of beneficial bacteria,particularly Lactobacillus,with the positive effects being more pronounced in the first 2 weeks after weaning.However,the risk of post-weaning diarrhea may increase as pigs get older due to reduced lactase activity,high dietary lactose concentrations,and larger feed intakes,all of which may lead to excessive lactose fermentation in the intestine of the pig.Therefore,dietary lactose levels exert different effects on growth performance and gastrointestinal physiological functions in different feeding phases of weanling pigs.However,no formal recommendation of lactose for weanling pigs has been reported.A meta-analysis approach was used to determine that diets fed to swine should include 20%,15%,and 0 lactose from d 0-7,d 7-14,and d 14-35 post-weaning,respectively.However,sustainable swine production demands that economics must also be taken into account as lactose and lactose containing ingredients are expensive.Therefore,alternatives to lactose,so called“lactose equivalents”have also been studied in an effort to decrease feed cost while maintaining piglet performance with lower dietary lactose inclusions.In summary,the present review investigated dose-response effects of dietary lactose supplementation to exert positive responses and begin to elucidate its mechanisms of action in postweaning pig diets.The results may help to replace some or all lactose in the diet of weanling pigs,while improving production economics given the high cost of lactose and availability in some swine production markets.展开更多
There has been a surge of interest in acetone-butanol-ethanol fermentations of Clostridium acetobutylicum due to its capacity to ferment many carbohydrates found in biomass. This metabolic diversity makes it a promisi...There has been a surge of interest in acetone-butanol-ethanol fermentations of Clostridium acetobutylicum due to its capacity to ferment many carbohydrates found in biomass. This metabolic diversity makes it a promising candidate for conversion of inexpensive, heterogeneous carbohydrate feedstocks to biofuels. Galactose is present in many such feedstocks due to its incorporation in plant cell walls. C. acetobutylicum encodes two galactose utilization pathways, the Leloir (LP) and the tagatose-6-P (T6P), and a previous study indicated genes for these pathways was differentially regulated during growth on galactose and lactose. In the current study we utilized quantitative PCR to further investigate gene expression levels and to show both pathways which were subject to carbon catabolite repression. During growth on galactose, mRNA for galactose-6-P isomerase from the T6P was induced to a greater extent than mRNA for glactokinase, the first enzyme in the LP. The galactose-6-P isomerase mRNAs were also more abundant than galactokinase mRNAs during growth on galactose. Analysis of theoretical ATP requirements to generate essential precursor metabolites indicated: 1) the LP is more efficient at generating upper glycolytic intermediates, 2) the T6P is more efficient at forming ATP, lower glycolytic intermediates and TCA cycle intermediates, 3) a combination of the two pathways is most efficient for forming precursor metabolites found in the pentose phosphate pathway. From this it can be suggested that the two pathways have different roles in the organism with the T6P generating most ATP and precursor metabolites and the LP providing upper glycolytic metabolites.展开更多
AIM: To validate 4-sample lactose hydrogen breath testing(4SLHBT) compared to standard 13-sample LHBT in the clinical setting.METHODS: Irritable bowel syndrome patients with diarrhea(IBS-D) and healthy volunteers(HVs)...AIM: To validate 4-sample lactose hydrogen breath testing(4SLHBT) compared to standard 13-sample LHBT in the clinical setting.METHODS: Irritable bowel syndrome patients with diarrhea(IBS-D) and healthy volunteers(HVs) were enrolled and received a 10 g, 20 g, or 40 g doselactose hydrogen breath test(LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h(13 measurements). The detection rates of lactose malabsorption(LM) and lactose intolerance(LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT.RESULTS: Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups(P < 0.001). 4SLHBT showed excellent diagnostic concordance with standard LHBT(97%-100%, Kappa 0.815-0.942) with high sensitivity(90%-100%) and specificity(100%) at all three lactose doses in both groups.CONCLUSION: Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice.展开更多
A cellulase producing bacterium (E3 strain) was isolated from fecal matter of elephant and identified as Bacillus sp. using 16S rDNA sequenced based molecular phylogenetic approach. While studying the effect of substr...A cellulase producing bacterium (E3 strain) was isolated from fecal matter of elephant and identified as Bacillus sp. using 16S rDNA sequenced based molecular phylogenetic approach. While studying the effect of substrates like Carboxymethyl cellulose (CMC), avicel, starch, maltose, sucrose, glucose, fructose, galactose and lactose on cellulase production, it was found that CMC was best carbon source induced cellulase production followed by lactose in this bacterial strain. A positive synergistic effect of lactose with CMC was also observed with enhancement of 5 - 6 times in cellulase production. The optimum cellulase production was recorded with 1% CMC and 1% lactose when added individually in the Omeliansky’s medium. The results showed that addition lactose with CMC greatly enhances the production and activity of various cellulase enzymes. The optimal fermentation conditions for the biosynthesis of cellulase by this strain were found to be temperature: 37℃, pH 7.0. The nitrogen source NH4Cl at 0.15% was optimum for cellulase production by this bacterium.展开更多
Lactose malabsorption (LM) is the incomplete hydrolysis of lactose due to lactase deficiency, which may occur as a primary disorder or secondary to other intestinal diseases. Primary adult-type hypolactasia is an auto...Lactose malabsorption (LM) is the incomplete hydrolysis of lactose due to lactase deficiency, which may occur as a primary disorder or secondary to other intestinal diseases. Primary adult-type hypolactasia is an autosomal recessive condition resulting from the physiological decline of lactase activity. Different methods have been used to diagnose LM. Lactose breath test represents the most reliable technique. A recent consensus conference has proposed the more physiological dosage of 25 g of lactose and a standardized procedure for breath testing. Recently a new genetic test, based on C/T13910 polymorphism, has been proposed for the diagnosis of adult-type hypolactasia, complementing the role of breath testing. LM represents a wellknown cause of abdominal symptoms although only some lactose malabsorbers are also intolerants. Diagnosing lactose intolerance is not straightforward. Many non-malabsorber subjects diagnose themselves as being lactose intolerant. Blind lactose challenge studies should be recommended to obtain objective results. Besides several studies indicate that subjects with lactose intolerance can ingest up to 15 g of lactose with no or minor symptoms. Therefore a therapeutic strategy consists of a lactose restricted diet avoiding the nutritional disadvantages of reduced calcium and vitamin intake. Various pharmacological options are also available. Unfortunately there is insufficient evidence that these therapies are effective. Further double-blind studies are needed to demonstrate treatment effectiveness in lactose intolerance.展开更多
Dry powder inhalers are often formulated by attaching micronized drug particles onto carrier particles, which are generally lactose. In this study, commercially available lactose was air jet milled to produce unique s...Dry powder inhalers are often formulated by attaching micronized drug particles onto carrier particles, which are generally lactose. In this study, commercially available lactose was air jet milled to produce unique slab-like coarse carrier particles, which have larger and rougher surfaces compared to other commercially available lactose. Two key processing factors, i.e.,classifier speed and jet milling pressure, were systematically investigated. The largest fraction of slab-like particles in the resulting powder was obtained at a classifier speed of 3000 rpm.The slab-like coarse carrier particles are expected to exhibit superior performance than commercial lactose due to their unique surface properties.展开更多
The purpose of this study was to investigate the spray dried lactose as carrier for dry powder inhalation(DPI).The lactose particles were prepared by spray drying,then the particle size,shape and crystal form were cha...The purpose of this study was to investigate the spray dried lactose as carrier for dry powder inhalation(DPI).The lactose particles were prepared by spray drying,then the particle size,shape and crystal form were characterized by laser diffraction,scanning electron microscopy(SEM),X-ray diffraction(XRD)and differential scanning calorimetry(DSC).The spray dried lactose particles were spherical and amorphous,but would transfer to crystal form when storage humidity was above 32%.Thus,the humidity of the storage environment should be controlled below 30%strictly in order to maintain the amorphous nature of spray dried lactose which is a great benefit to DPI development.展开更多
The lactose-fermenter Enterobacteriaceae are the most frequent cause of clinical infection in our country. The objective of this study was to isolate and identify the most common lactose-fermenter Enterobacteriaceae f...The lactose-fermenter Enterobacteriaceae are the most frequent cause of clinical infection in our country. The objective of this study was to isolate and identify the most common lactose-fermenter Enterobacteriaceae from clinical samples, including urine, blood, wounds, and sputum, obtained from the local hospital and from environmental samples from a chicken farm, agriculture soil, and water from the Tigris River in Baghdad City. The study also aimed at establishing the antibiotic resistance patterns of the isolated bacteria. A total of 155 bacterial isolates were identified from 10 genera according to the Vitek 2 system. The most common bacterial isolates from the clinical and environmental samples were Escherichia coli and Klebsiella pneumoniae, respectively. The antibiotic resistance patterns showed that all clinical and environmental isolates were multidrug resistant to β-lactam (except carbapenems) drug and aminoglycosides and more sensitive to carbapenems.展开更多
This prospective study was carried out to assess the sensitivity and resistance pattern of lactose non-fermenting Escherichia coli from July 2018 to December 2018 in the Laboratory of Microbiology at Luanda Medical Ce...This prospective study was carried out to assess the sensitivity and resistance pattern of lactose non-fermenting Escherichia coli from July 2018 to December 2018 in the Laboratory of Microbiology at Luanda Medical Center, Angola. Out of 1170 patient, a total of 120 urine specimens infected with Escherichia coli (>105 CFU/ml) were collected according to the routine protocol of urinalysis. Among these 120 isolates, 25 (21%) isolates were determined as “atypical”, lactose non-fermenting E. colis trains. The twenty-five lactose non-fermenting Escherichia coli strains isolated from urine samples in Luanda Medical Center were declared as Multiple Drugs-Resistant strains with high resistance to Cefalexine (100%), Cefuroxime (100%), Ceftriaxone (92%), Gentamycin (92%), Ciprofloxacin (72%) and Amoxiciclin/Clavulanic (80%). The alarming resistance level to the first-choice drugs for the treatment of urinary tract infections caused by non-fermentative lactose E. coli was observed.展开更多
Enrichment of yogurt with lactose addition may increase the growth of the yogurt starter culture (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) and enhance yogurt physico-chemical and senso...Enrichment of yogurt with lactose addition may increase the growth of the yogurt starter culture (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) and enhance yogurt physico-chemical and sensory attributes. The objectives of this study were to determine the influence of added lactose on the 1) physico-chemical characteristics, including the final lactose content of yogurt, during its shelf life;2) growth of the yogurt starter culture over yogurt shelf life and 3) the sensory attributes of yogurt. Fat free plain set-type yogurt was manufactured using 0%, 1%, 3% and 5% w/w added lactose to accomplish objectives 1 and 2. For objective 3, a blueberry yogurt was manufactured using the same lactose levels. Analyses for plain set-type yogurt were conducted at 7 days intervals during 35 days of storage. Sensory evaluation was conducted on flavored yogurt three days after its manufacture. Data were analyzed using Proc Mixed model of SAS®9.3 program. Significant differences between means were analyzed at α = 0.05 using Tukey adjustment. Lactose addition influenced some of the yogurt characteristics in a positive manner. Lactose contents of yogurts with lactose added at 1%, 3% and 5% stayed higher in that proportion than control throughout the 35 days of storage. Yogurts containing 5% w/w added lactose had the lowest pH. Yogurts containing 5% w/w added lactose had significantly the highest syneresis values compared to 0%, 1% and 3% w/w added lactose during storage period at day 7 and from day 21 onwards. Use of 5% w/w added lactose resulted in significantly higher counts of Streptococcus thermophilus compared to control and this bacterial survival was the highest for 1% w/w added lactose compared to the rest. The overall liking scores indicated that yogurts containing added lactose were preferred over control. For taste, sourness and sweetness samples containing added lactose had higher scores than control. The consumer acceptability of yogurts increased as lactose addition increased. The acceptability of yogurts and purchase intent frequency scores markedly increased with the addition of lactose.展开更多
Carbohydrate fatty acid esters have been shown to inhibit the growth of bacteria in growth media. In this study, the antilisterial activities of the carbohydrate esters lactose monodecanoate (LMD) and lactose monolaur...Carbohydrate fatty acid esters have been shown to inhibit the growth of bacteria in growth media. In this study, the antilisterial activities of the carbohydrate esters lactose monodecanoate (LMD) and lactose monolaurate (LML) were tested in milk samples with variable fat content (up to 10%) and at different temperatures (37°C, 24°C and 5°C) after inoculation with a 5-strain Listeria monocytogenes cocktail. Both LMD and LML demonstrated antilisterial properties against L. monocytogenes in milk, with the observed log reductions in the LMD milk samples being higher than those in the LML samples at all tested temperatures. LMD in 1% and 2% fat milk was found to be bactericidal with no Listeria growth by day 6. LMD showed significant antilisterial activity in milk samples containing up to 9% fat at 37°and in samples with up to 3.5% fat at 24°C and in milk samples with up to 2% fat at 5°C. LML showed significant Listeria log reductions at 37°C with milk containing up to 9% fat but showed no microbial inhibition in milk in any samples at 24°C and 5°C. Although carbohydrate fatty acid esters have proven microbial bactericidal/bacteriostatic properties in growth media, their antimicrobial properties are reduced in a food system containing fat and at temperatures lower than 37°C. The significance of this research is identifying food constituents and storage temperatures that limit the microbial inhibitory properties of lactose esters to ensure appropriate use as potential food grade antilisterial agents.展开更多
Sugar fatty acid esters (SFAE) are a class of synthetic emulsifiers used in the food, pharmaceutical, and personal care industries. The influence of the fatty acid chain length on the emulsification properties of lact...Sugar fatty acid esters (SFAE) are a class of synthetic emulsifiers used in the food, pharmaceutical, and personal care industries. The influence of the fatty acid chain length on the emulsification properties of lactose fatty acid esters (LFAE) including lactose monooctanoate (LMO), lactose monodecanoate (LMD), lactose monolaurate (LML) and lactose monomyristate (LMM) was investigated in this study. The stability of the emulsions as well as the oil droplet size distribution in 20% soybean oil-in-water emulsions was measured at 0.1%, 0.25% and 0.5% of LFAE concentrations. In order of LFAE with the strongest emulsion stabilization characteristics were LML, LMD, LMO and LMM. Oil droplet distributions resulted in the same trend, with LML and LMD maintaining the smallest droplet sizes and thus the most stable emulsion. The hydrophilic-lipophilic balance (HLB) and critical micelle concentrations were determined for each LFAE. An increase in HLB value was seen with an increased CMC value for each LFAE, showing the strength of the linear relationship between these two measured values. Additionally, there was a decrease in HLB and CMC values with a decrease in the fatty acid chain length of each LFAE. This research showed that LML and LMD formed more stable emulsions, even with HLB and CMC values higher than those of LMM suggesting HLB and CMC values alone do not predict emulsifier effectiveness.展开更多
Lactose breath test (LBT) is considered the gold standard for the diagnosis of lactose malabsorption. The test is considered positive for a peak of hydrogen (H2) ≥ 20 parts per million (ppm) above the baseline. Some ...Lactose breath test (LBT) is considered the gold standard for the diagnosis of lactose malabsorption. The test is considered positive for a peak of hydrogen (H2) ≥ 20 parts per million (ppm) above the baseline. Some patients (pts) showed a rapid peak between 30 and 90 minutes after lactose ingestion. The aim of this study was to evaluate the predictive value of an early peak during a LBT and an accelerated oro-cecal transit time (OCTT). We retrospectively analyzed all pts who referred to our Gastroenterology unit for Irritable Bowel Syndrome, from January to September 2012, who performed LBT, glucose and lactulose breath test. We consider a positive LBT for a peak of H2 > 20 ppm, a positive GHBT for a peak >12 ppm and we considered a normal OCCT a peak of H2 ≥ 10 ppm between 75 ± 105 min after lactulose load. The correlation between LBT and OCTT was evaluated by Pearson score. 93 pts (65 F/28 M mean age 47 ± 6 years) with a positive LBT, without small intestinal bacterial overgrowth were analyzed: 46 pts (32 F/14 M;mean age 48 ± 6 years) with an early peak (2 (≥20 ppm) were enrolled as case, and 47 pts matched for sex and age with a peak of H2 after 90 min were enrolled as controls. 72% (33/46) of the group with an early peak showed an accelerated, 17% (8/46) a normal and 11% (5/46) a delayed OCTT. Meanwhile, in control group 40.4% (19/47) showed a normal, 57.5% (27/47) a delayed and just 1 pts an accelerated OCTT. The specificity and sensibility of LBT for an accelerated OCTT were 97.9% and 71.7% respectively. The positive predictive value of LBT for an accelerated OCTT is 97.1%;the negative predictive value is 78%. There is a significant correlation between LBT and OCTT (p The presence of an early peak of H2 between 30 and 90 min after the ingestion of 25 gr of lactose could predict the presence of an accelerated OCTT in 97% of pts. If confirmed by further study, in this subset of pts, lactulose breath test for evaluating OCTT could be avoided.展开更多
The oxidations of D-fructose and D-lactose were monitored spectrophotometrically by potassium permanganate in acidic medium at λmax 545 nm. Reaction demonstrated that the two oxidative species of permanganate were in...The oxidations of D-fructose and D-lactose were monitored spectrophotometrically by potassium permanganate in acidic medium at λmax 545 nm. Reaction demonstrated that the two oxidative species of permanganate were involved in an acidic oxidation of the sugars. It was established that respective acids of sugars as well as arabinonic and formic acid were the oxidation products. Respective acids of sugars were the results of reactive oxygen species of permanganate ions in acidic conditions while arabinonic and formic acids due to the cleavage of C__C bond through MnO-4 species. It was first order kinetics with respect to [MnO-4 ], [fructose], [lactose] and [H+]. Hg was used to accelerate the slow oxidation of lactose. Effect of varying salt electrolyte concentration was insignificant showing that the molecular species was involved in the rate determining step. Formic and arabinonic acids and respective acids were analyzed through spot and spectroscopic studies respectively. Reaction was monitored at different temperatures and thermodynamics activation parameters were determined. A mechanism consistent with kinetic studies, spectral evidences, stoichiometry of the reactions and product analysis has been proposed for the oxidation of fructose and lactose in absence and presence of catalyst respectively.展开更多
BACKGROUND Lactose malabsorption is variably associated with lactose intolerance (LI). The determinants of symptom onset have not yet been completely identified. Visceral sensitivity may play a role in the pathogenesi...BACKGROUND Lactose malabsorption is variably associated with lactose intolerance (LI). The determinants of symptom onset have not yet been completely identified. Visceral sensitivity may play a role in the pathogenesis of functional symptoms;an increasing bulk of clinical and research data suggests the importance of the brain-gut interaction in intestinal bowel syndrome. AIM: To assess the impact of anxiety on LI symptoms, and the correlation between gas production during Lactose Breath test (LBT) and the intensity of gastrointestinal symptoms (GI) in anxious (A) and non-anxious (NA) patients. METHODS: LBT was carried out in 104 consecutive participants referred to our Gastroenterology Unit. GI symptoms were evaluated using the visual analogue scale (VAS: 0-10) throughout the LBT. All patients completed the HADS to determine anxiety. RESULTS LBT was positive in 70/104 (67%) participants;49/ 104 (47%) showed significant anxiety symptoms (>10 items). In A subjects we did not find any significant correlation between gas levels and abdominal LI symptoms scores throughout the LBT. A subject showed higher scores for all LI symptoms as compared with other participants, independently of LBT results. NA pts with positive LBT showed higher scores for all LI symptoms, as compared to negative subjects. LIMITATIONS: The predominant gender is female but it is in agreement with literature data that show a preponderance of IBS in women. CONCLUSIONS: A status significantly influences the severity of all LI symptoms and does not strictly correlate with lactase deficiency. Conversely, among NA subjects LI symptoms increase along with H2 production. Anxiety seems to be a confounding factor in IBS pts.展开更多
Lactose, the sugar naturally present in milk, provides energy to lactic acid bacteria used in fermented dairy foods. Increasing concentrations of lactose may improve survivability of lactic acid bacteria in the dairy ...Lactose, the sugar naturally present in milk, provides energy to lactic acid bacteria used in fermented dairy foods. Increasing concentrations of lactose may improve survivability of lactic acid bacteria in the dairy foods and in human gut enhancing their probiotic benefits. Acid tolerance is an important probiotic characteristic. The objective was to determine the influence of lactose on acid tolerance of yogurt starter culture </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Streptococcus thermophiles</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> ST-M5 and </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lactobacillus bulgaricus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> LB-12. The M 17 broth was used for </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Streptococcus thermophiles</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:""><span style="font-family:Verdana;"> ST-M5 and MRS broth was used for</span><i> </i></span><i><span style="font-family:Verdana;"><i></span></i><i><span style="font-family:Verdana;">Lactobacillus bulgaricus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">LB-12</span><i><span style="font-family:Verdana;">.</span></i><span style="font-family:Verdana;"> Lactose was added to both broths at 0% (control), 1%, 3%, and 5% (wt/vol). Both broths were acidified to pH 2.0. Upon sterilizing and tempering, both broths were inoculated. Acid tolerance </span></span><span style="font-family:Verdana;">was </span><span style="font-family:Verdana;">determined as viable counts in acidified broths after 120 minutes of incubations. In an incubation period of 2 hours, dilutions were plated every 30 minutes. Three replications were conducted. The highest acid tolerance for </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Streptococcus thermophiles</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> ST-M5 and </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lactobacillus bulgaricus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> LB-12, was observed in lactose concentration of 3% and 5% (wt/vol).展开更多
<span style="font-size:14px;">Due to the widespread use of antibiotics, the bad ecological situation, fer</span><span style="font-size:14px;" "="">mented milk drink...<span style="font-size:14px;">Due to the widespread use of antibiotics, the bad ecological situation, fer</span><span style="font-size:14px;" "="">mented milk drinks are gaining more and more popularity because of associating with an array of health benefits. Fermented milk products contain a unique in its kind disaccharide of animal origin lactose, which has the ability to stimulate the development of lactic acid microorganisms that suppress the vital activity of pathogenic microflora in the human intestine, promoting the absorption of calcium, magnesium and phosphorus.</span><span style="font-size:10.0pt;font-family:;" "=""> </span><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:14px;">A significant part of the </span><span style="font-size:14px;">world’s population suffers from lactose intolerance, linked to a genetically</span> <span><span style="font-size:14px;">determined deficiency of the </span><i><span style="font-size:14px;">β</span></i><span style="font-size:14px;">-galactosidase enzyme, which is one of the</span></span><span style="font-size:14px;"> main reasons for the decrease in demand for dairy products among consumers suffering from primary or acquired intolerance to milk sugar.</span></span><span style="font-size:10.0pt;font-family:;" "=""> </span><span style="font-size:14px;" "="">Lactose is a natural disaccharide contained in dairy products. Lactase deficiency is a variant of fermentopathy caused by the inability to break down lactose due to the activity decrease of lactase—the parietal digestion enzyme in the small intestine. Lactose intolerance in the gastrointestinal tract of a person suffering from hypo- and alactasia leads to dispersion, diarrhea and other undesirable phenomena. For the successful prevention and treatment of these diseases, it is necessary to reduce or completely eliminate the lactose intake.</span><span style="font-size:10.0pt;font-family:;" "=""> </span><span style="font-size:14px;" "="">A technology for lactose-free milk production was developed using fermentation technology. On the basis of lactose-free milk, a range of lactose-free yoghurts was developed of animal origin of the following types: natural, enriched and fortified. Flax seeds, sesame seeds and chia seeds, which are rich in vitamins, were used to produce a range of enriched yogurts. To obtain fortified yoghurts, the mineral iron was used, which prevent the development of anemia and oncological pathologies. Experimental assortment of lactose-free yoghurts was assessed by physicochemical and organoleptic methods. All developed samples meet the standards of technical documentation for this type of food product. The organoleptic characteristics were highly appreciated. Developed lactose-</span><span style="font-size:14px;" "="">free products are an opportunity for many people to return to a normal</span><span style="font-size:14px;" "=""> healthy diet.</span>展开更多
Lactose intolerance is becoming a health state that requires the restriction of dairy products in the diet of people suffering from this condition. But milk and dairy products, due to a well-balanced composition in th...Lactose intolerance is becoming a health state that requires the restriction of dairy products in the diet of people suffering from this condition. But milk and dairy products, due to a well-balanced composition in the main macro and micronutrients, cannot be missing from the diet of the consumer of any age. For these reasons, in recent years, in the milk processing industry, the production of low-lactose or lactose-free dairy products is explored. To reduce the lactose content of dairy raw materials, various industrial and biotechnological methods were used: enzymatic hydrolysis of lactose, baromembranous methods, bioconversion of lactose by lactic bacteria and others. The most widely used lactase enzymes in the industry are mesophilic enzymes from filamentous fungi <span>(<i>Aspergillus</i> <i>spp</i>.)</span> and yeasts <span>(<i>Kluyveromyces</i> <i>spp</i>.). </span>Therefore, the aim of this study was to evaluate the effect of the commercial enzyme <i>β</i>-galactosidase on the hydrolysis of cow’s milk at different enzyme <span>con</span><span>centrations, temperatures and pH. Two commercial enzymes <i>β</i>-galactosi</span><span>dase</span> obtain<span>ed from <i>Bacillus</i><span> <i>licheniformis</i></span> and <i>β</i>-galactosidase obtained from <i>Kluyve</i></span><i>romyces</i><span> <i>lactis</i></span>, were used in this study, according to information provided by the manufacturer. The thermal stability of lactose, the effect of milk pH, the effect of temperature, duration of hydrolysis and the amount of enzymes on the lactose hydrolysis degree and the sweetness degree of milk were determined. Research has identified the optimal parameters for obtaining a high degree of lactose hydrolysis in the use of these enzymes. Therefore, to ensure a high lactose hydrolysis degree (over 80%), the following lactose hydrolysis regimens were identified: temperature 4°C - 6<span style="white-space:normal;">°</span>C, 0.3% <i>Bacillus</i><span> <i>licheniformis</i></span> enzymes, duration 4 hours;temperature 4<span style="white-space:normal;">°</span>C - 6<span style="white-space:normal;">°</span>C, 0.3% enzymes from <i>Klavyromyces</i><span> <i>lactis</i></span>, duration 12 hours and temperature 38<span style="white-space:normal;">°</span>C - 40<span style="white-space:normal;">°</span>C, 0.15% enzymes from (<i>Bacillus</i><span> <i>licheniformis</i></span> or <i>Klavyromyces</i><span> <i>lactis</i></span>), duration 2 - 3 hours. The results obtained allow the efficient use of <i>Bacillus</i><span> <i>licheniformis</i></span> and <i>Klavyromyces</i><span> <i>lactis</i></span> enzymes in industrial processes for the manufacture of “lactose-free” or “low-lactose” drinking milk and fermented dairy products for people with lactose intolerance.展开更多
The lactose-fermenter Enterobacteriaceae are the most frequent cause of clinical infection in our country. The objective of this study was to isolate and identify the most common lactose-fermenter Enterobacteriaceae f...The lactose-fermenter Enterobacteriaceae are the most frequent cause of clinical infection in our country. The objective of this study was to isolate and identify the most common lactose-fermenter Enterobacteriaceae from clinical samples, including urine, blood, wounds, and sputum, obtained from the local hospital and from environmental samples from a chicken farm, agriculture soil, and water from the Tigris River in Baghdad City. The study also aimed at establishing the antibiotic resistance patterns of the isolated bacteria. A total of 155 bacterial isolates were identified from 10 genera according to the Vitek 2 system. The most common bacterial isolates from the clinical and environmental samples were Escherichia coli and Klebsiella pneumoniae, respectively. The antibiotic resistance patterns showed that all clinical and environmental isolates were multidrug resistant to β-lactam (except carbapenems) drug and aminoglycosides and more sensitive to carbapenems.展开更多
基金Supported by Grants of J-milk(Japan Dairy Association)。
文摘BACKGROUND Lactose intolerance(LI)is commonly seen in East Asian countries.Several studies showed that lactose or milk loading has been used as a treatment for lactose malabsorption(LM)in Western countries,but there have been no reports regarding this type of treatment in Japan.As lactose or milk loading requires ingestion of large amounts of lactose within a short period,this is considered to be too harsh for Japanese people because of their less habitual milk consumption(175 mL per day in average)than Western people.In this study,we demonstrated lactose tolerance acquisition in a suitable way for Japanese.AIM To examine the efficacy of lactose(cow’s milk)loading treatment in patients with LM.METHODS Individuals with abdominal symptoms induced by milk or dairy products(LI symptoms)were identified with a questionnaire.A 20 g lactose hydrogen breath test(LHBT)was carried out to confirm LM diagnosis and to evaluate co-existence of small intestinal bacterial overgrowth(SIBO).Respondents diagnosed with LM were selected as study subjects and were treated with incremental loads of cow’s milk,starting from 30 mL and increasing up to 200 mL at 4-7 d intervals.After the treatment,changes in symptoms and LM diagnostic value of 20 g LHBT were investigated.Stool samples pre-and post-treatment were examined for changes in intestinal microbiota using 16S rRNA sequencing.Informed consent was obtained prior to each stage of the study.RESULTS In 46 subjects with LI symptoms(10-68 years old,mean age 34 years old)identified with the questionnaire,35(76.1%)were diagnosed with LM by 20 g LHBT,and 6 had co-existing SIBO.The treatment with incremental cow’s milk was carried out in 32 subjects diagnosed with LM(14-68 years old,median age 38.5 years old).The mean period of the treatment was 41±8.6 d.Improvement of symptoms was observed in 29(90.6%;95%confidence interval:75.0%-98.0%)subjects.Although 20 g LHBT indicated that 10(34.5%)subjects had improved diagnostic value of LM,no change was observed in 16(55.2%)subjects.Analysis of the fecal intestinal microbiota showed a significant increase in Blautia in 7 subjects who became symptom-free after the treatment(P=0.0313).CONCLUSION LM was diagnosed in approximately 75%of the subjects who had LI.Incremental loads of cow’s milk is regarded as a useful treatment for LM without affecting everyday life.
文摘Lactose plays a crucial role in the growth performance of pigs at weaning because it is a palatable and easily digestible energy source that eases the transition from milk to solid feed.However,the digestibility of lactose declines after weaning due to a reduction in endogenous lactase activity in piglets.As a result,some lactose may be fermented in the gastrointestinal tract of pigs.Fermentation of lactose by intestinal microbiota yields lactic acid and volatile fatty acids,which may positively regulate the intestinal environment and microbiome,resulting in improved gastrointestinal health of weanling pigs.We hypothesize that the prebiotic effect of lactose may play a larger role in weanling pig nutrition as the global feed industry strives to reduce antibiotic usage and pharmacological levels of zinc oxide and supra-nutritional levels of copper.Evidence presented in this review indicates that high dietary lactose improves growth performance of piglets,as well as the growth of beneficial bacteria,particularly Lactobacillus,with the positive effects being more pronounced in the first 2 weeks after weaning.However,the risk of post-weaning diarrhea may increase as pigs get older due to reduced lactase activity,high dietary lactose concentrations,and larger feed intakes,all of which may lead to excessive lactose fermentation in the intestine of the pig.Therefore,dietary lactose levels exert different effects on growth performance and gastrointestinal physiological functions in different feeding phases of weanling pigs.However,no formal recommendation of lactose for weanling pigs has been reported.A meta-analysis approach was used to determine that diets fed to swine should include 20%,15%,and 0 lactose from d 0-7,d 7-14,and d 14-35 post-weaning,respectively.However,sustainable swine production demands that economics must also be taken into account as lactose and lactose containing ingredients are expensive.Therefore,alternatives to lactose,so called“lactose equivalents”have also been studied in an effort to decrease feed cost while maintaining piglet performance with lower dietary lactose inclusions.In summary,the present review investigated dose-response effects of dietary lactose supplementation to exert positive responses and begin to elucidate its mechanisms of action in postweaning pig diets.The results may help to replace some or all lactose in the diet of weanling pigs,while improving production economics given the high cost of lactose and availability in some swine production markets.
文摘There has been a surge of interest in acetone-butanol-ethanol fermentations of Clostridium acetobutylicum due to its capacity to ferment many carbohydrates found in biomass. This metabolic diversity makes it a promising candidate for conversion of inexpensive, heterogeneous carbohydrate feedstocks to biofuels. Galactose is present in many such feedstocks due to its incorporation in plant cell walls. C. acetobutylicum encodes two galactose utilization pathways, the Leloir (LP) and the tagatose-6-P (T6P), and a previous study indicated genes for these pathways was differentially regulated during growth on galactose and lactose. In the current study we utilized quantitative PCR to further investigate gene expression levels and to show both pathways which were subject to carbon catabolite repression. During growth on galactose, mRNA for galactose-6-P isomerase from the T6P was induced to a greater extent than mRNA for glactokinase, the first enzyme in the LP. The galactose-6-P isomerase mRNAs were also more abundant than galactokinase mRNAs during growth on galactose. Analysis of theoretical ATP requirements to generate essential precursor metabolites indicated: 1) the LP is more efficient at generating upper glycolytic intermediates, 2) the T6P is more efficient at forming ATP, lower glycolytic intermediates and TCA cycle intermediates, 3) a combination of the two pathways is most efficient for forming precursor metabolites found in the pentose phosphate pathway. From this it can be suggested that the two pathways have different roles in the organism with the T6P generating most ATP and precursor metabolites and the LP providing upper glycolytic metabolites.
基金Supported by Nestle Research International and The Science and Technology Department of Zhejiang Province,No.2009C14016
文摘AIM: To validate 4-sample lactose hydrogen breath testing(4SLHBT) compared to standard 13-sample LHBT in the clinical setting.METHODS: Irritable bowel syndrome patients with diarrhea(IBS-D) and healthy volunteers(HVs) were enrolled and received a 10 g, 20 g, or 40 g doselactose hydrogen breath test(LHBT) in a randomized, double-blinded, controlled trial. The lactase gene promoter region was sequenced. Breath samples and symptoms were acquired at baseline and every 15 min for 3 h(13 measurements). The detection rates of lactose malabsorption(LM) and lactose intolerance(LI) for a 4SLHBT that acquired four measurements at 0, 90, 120, and 180 min from the same data set were compared with the results of standard LHBT.RESULTS: Sixty IBS-D patients and 60 HVs were studied. The genotype in all participants was C/C-13910. LM and LI detection rates increased with lactose dose from 10 g, 20 g to 40 g in both groups(P < 0.001). 4SLHBT showed excellent diagnostic concordance with standard LHBT(97%-100%, Kappa 0.815-0.942) with high sensitivity(90%-100%) and specificity(100%) at all three lactose doses in both groups.CONCLUSION: Reducing the number of measurements from 13 to 4 samples did not significantly impact on the accuracy of LHBT in health and IBS-D. 4SLHBT is a valid test for assessment of LM and LI in clinical practice.
文摘A cellulase producing bacterium (E3 strain) was isolated from fecal matter of elephant and identified as Bacillus sp. using 16S rDNA sequenced based molecular phylogenetic approach. While studying the effect of substrates like Carboxymethyl cellulose (CMC), avicel, starch, maltose, sucrose, glucose, fructose, galactose and lactose on cellulase production, it was found that CMC was best carbon source induced cellulase production followed by lactose in this bacterial strain. A positive synergistic effect of lactose with CMC was also observed with enhancement of 5 - 6 times in cellulase production. The optimum cellulase production was recorded with 1% CMC and 1% lactose when added individually in the Omeliansky’s medium. The results showed that addition lactose with CMC greatly enhances the production and activity of various cellulase enzymes. The optimal fermentation conditions for the biosynthesis of cellulase by this strain were found to be temperature: 37℃, pH 7.0. The nitrogen source NH4Cl at 0.15% was optimum for cellulase production by this bacterium.
文摘Lactose malabsorption (LM) is the incomplete hydrolysis of lactose due to lactase deficiency, which may occur as a primary disorder or secondary to other intestinal diseases. Primary adult-type hypolactasia is an autosomal recessive condition resulting from the physiological decline of lactase activity. Different methods have been used to diagnose LM. Lactose breath test represents the most reliable technique. A recent consensus conference has proposed the more physiological dosage of 25 g of lactose and a standardized procedure for breath testing. Recently a new genetic test, based on C/T13910 polymorphism, has been proposed for the diagnosis of adult-type hypolactasia, complementing the role of breath testing. LM represents a wellknown cause of abdominal symptoms although only some lactose malabsorbers are also intolerants. Diagnosing lactose intolerance is not straightforward. Many non-malabsorber subjects diagnose themselves as being lactose intolerant. Blind lactose challenge studies should be recommended to obtain objective results. Besides several studies indicate that subjects with lactose intolerance can ingest up to 15 g of lactose with no or minor symptoms. Therefore a therapeutic strategy consists of a lactose restricted diet avoiding the nutritional disadvantages of reduced calcium and vitamin intake. Various pharmacological options are also available. Unfortunately there is insufficient evidence that these therapies are effective. Further double-blind studies are needed to demonstrate treatment effectiveness in lactose intolerance.
基金the funding support for this study from GEA-NUS PPRL (N-148-000-008-001)SERC Grant No. 102 169 0049 (R-148-000-157-305)partial support from the NSF through the NNIN program
文摘Dry powder inhalers are often formulated by attaching micronized drug particles onto carrier particles, which are generally lactose. In this study, commercially available lactose was air jet milled to produce unique slab-like coarse carrier particles, which have larger and rougher surfaces compared to other commercially available lactose. Two key processing factors, i.e.,classifier speed and jet milling pressure, were systematically investigated. The largest fraction of slab-like particles in the resulting powder was obtained at a classifier speed of 3000 rpm.The slab-like coarse carrier particles are expected to exhibit superior performance than commercial lactose due to their unique surface properties.
基金This work was supported by the National Natural Science Foundation of China(No.:81173002)the National Science and Technology Support Program(No.:2012BAI35B02).
文摘The purpose of this study was to investigate the spray dried lactose as carrier for dry powder inhalation(DPI).The lactose particles were prepared by spray drying,then the particle size,shape and crystal form were characterized by laser diffraction,scanning electron microscopy(SEM),X-ray diffraction(XRD)and differential scanning calorimetry(DSC).The spray dried lactose particles were spherical and amorphous,but would transfer to crystal form when storage humidity was above 32%.Thus,the humidity of the storage environment should be controlled below 30%strictly in order to maintain the amorphous nature of spray dried lactose which is a great benefit to DPI development.
文摘The lactose-fermenter Enterobacteriaceae are the most frequent cause of clinical infection in our country. The objective of this study was to isolate and identify the most common lactose-fermenter Enterobacteriaceae from clinical samples, including urine, blood, wounds, and sputum, obtained from the local hospital and from environmental samples from a chicken farm, agriculture soil, and water from the Tigris River in Baghdad City. The study also aimed at establishing the antibiotic resistance patterns of the isolated bacteria. A total of 155 bacterial isolates were identified from 10 genera according to the Vitek 2 system. The most common bacterial isolates from the clinical and environmental samples were Escherichia coli and Klebsiella pneumoniae, respectively. The antibiotic resistance patterns showed that all clinical and environmental isolates were multidrug resistant to β-lactam (except carbapenems) drug and aminoglycosides and more sensitive to carbapenems.
文摘This prospective study was carried out to assess the sensitivity and resistance pattern of lactose non-fermenting Escherichia coli from July 2018 to December 2018 in the Laboratory of Microbiology at Luanda Medical Center, Angola. Out of 1170 patient, a total of 120 urine specimens infected with Escherichia coli (>105 CFU/ml) were collected according to the routine protocol of urinalysis. Among these 120 isolates, 25 (21%) isolates were determined as “atypical”, lactose non-fermenting E. colis trains. The twenty-five lactose non-fermenting Escherichia coli strains isolated from urine samples in Luanda Medical Center were declared as Multiple Drugs-Resistant strains with high resistance to Cefalexine (100%), Cefuroxime (100%), Ceftriaxone (92%), Gentamycin (92%), Ciprofloxacin (72%) and Amoxiciclin/Clavulanic (80%). The alarming resistance level to the first-choice drugs for the treatment of urinary tract infections caused by non-fermentative lactose E. coli was observed.
文摘Enrichment of yogurt with lactose addition may increase the growth of the yogurt starter culture (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) and enhance yogurt physico-chemical and sensory attributes. The objectives of this study were to determine the influence of added lactose on the 1) physico-chemical characteristics, including the final lactose content of yogurt, during its shelf life;2) growth of the yogurt starter culture over yogurt shelf life and 3) the sensory attributes of yogurt. Fat free plain set-type yogurt was manufactured using 0%, 1%, 3% and 5% w/w added lactose to accomplish objectives 1 and 2. For objective 3, a blueberry yogurt was manufactured using the same lactose levels. Analyses for plain set-type yogurt were conducted at 7 days intervals during 35 days of storage. Sensory evaluation was conducted on flavored yogurt three days after its manufacture. Data were analyzed using Proc Mixed model of SAS®9.3 program. Significant differences between means were analyzed at α = 0.05 using Tukey adjustment. Lactose addition influenced some of the yogurt characteristics in a positive manner. Lactose contents of yogurts with lactose added at 1%, 3% and 5% stayed higher in that proportion than control throughout the 35 days of storage. Yogurts containing 5% w/w added lactose had the lowest pH. Yogurts containing 5% w/w added lactose had significantly the highest syneresis values compared to 0%, 1% and 3% w/w added lactose during storage period at day 7 and from day 21 onwards. Use of 5% w/w added lactose resulted in significantly higher counts of Streptococcus thermophilus compared to control and this bacterial survival was the highest for 1% w/w added lactose compared to the rest. The overall liking scores indicated that yogurts containing added lactose were preferred over control. For taste, sourness and sweetness samples containing added lactose had higher scores than control. The consumer acceptability of yogurts increased as lactose addition increased. The acceptability of yogurts and purchase intent frequency scores markedly increased with the addition of lactose.
文摘Carbohydrate fatty acid esters have been shown to inhibit the growth of bacteria in growth media. In this study, the antilisterial activities of the carbohydrate esters lactose monodecanoate (LMD) and lactose monolaurate (LML) were tested in milk samples with variable fat content (up to 10%) and at different temperatures (37°C, 24°C and 5°C) after inoculation with a 5-strain Listeria monocytogenes cocktail. Both LMD and LML demonstrated antilisterial properties against L. monocytogenes in milk, with the observed log reductions in the LMD milk samples being higher than those in the LML samples at all tested temperatures. LMD in 1% and 2% fat milk was found to be bactericidal with no Listeria growth by day 6. LMD showed significant antilisterial activity in milk samples containing up to 9% fat at 37°and in samples with up to 3.5% fat at 24°C and in milk samples with up to 2% fat at 5°C. LML showed significant Listeria log reductions at 37°C with milk containing up to 9% fat but showed no microbial inhibition in milk in any samples at 24°C and 5°C. Although carbohydrate fatty acid esters have proven microbial bactericidal/bacteriostatic properties in growth media, their antimicrobial properties are reduced in a food system containing fat and at temperatures lower than 37°C. The significance of this research is identifying food constituents and storage temperatures that limit the microbial inhibitory properties of lactose esters to ensure appropriate use as potential food grade antilisterial agents.
文摘Sugar fatty acid esters (SFAE) are a class of synthetic emulsifiers used in the food, pharmaceutical, and personal care industries. The influence of the fatty acid chain length on the emulsification properties of lactose fatty acid esters (LFAE) including lactose monooctanoate (LMO), lactose monodecanoate (LMD), lactose monolaurate (LML) and lactose monomyristate (LMM) was investigated in this study. The stability of the emulsions as well as the oil droplet size distribution in 20% soybean oil-in-water emulsions was measured at 0.1%, 0.25% and 0.5% of LFAE concentrations. In order of LFAE with the strongest emulsion stabilization characteristics were LML, LMD, LMO and LMM. Oil droplet distributions resulted in the same trend, with LML and LMD maintaining the smallest droplet sizes and thus the most stable emulsion. The hydrophilic-lipophilic balance (HLB) and critical micelle concentrations were determined for each LFAE. An increase in HLB value was seen with an increased CMC value for each LFAE, showing the strength of the linear relationship between these two measured values. Additionally, there was a decrease in HLB and CMC values with a decrease in the fatty acid chain length of each LFAE. This research showed that LML and LMD formed more stable emulsions, even with HLB and CMC values higher than those of LMM suggesting HLB and CMC values alone do not predict emulsifier effectiveness.
文摘Lactose breath test (LBT) is considered the gold standard for the diagnosis of lactose malabsorption. The test is considered positive for a peak of hydrogen (H2) ≥ 20 parts per million (ppm) above the baseline. Some patients (pts) showed a rapid peak between 30 and 90 minutes after lactose ingestion. The aim of this study was to evaluate the predictive value of an early peak during a LBT and an accelerated oro-cecal transit time (OCTT). We retrospectively analyzed all pts who referred to our Gastroenterology unit for Irritable Bowel Syndrome, from January to September 2012, who performed LBT, glucose and lactulose breath test. We consider a positive LBT for a peak of H2 > 20 ppm, a positive GHBT for a peak >12 ppm and we considered a normal OCCT a peak of H2 ≥ 10 ppm between 75 ± 105 min after lactulose load. The correlation between LBT and OCTT was evaluated by Pearson score. 93 pts (65 F/28 M mean age 47 ± 6 years) with a positive LBT, without small intestinal bacterial overgrowth were analyzed: 46 pts (32 F/14 M;mean age 48 ± 6 years) with an early peak (2 (≥20 ppm) were enrolled as case, and 47 pts matched for sex and age with a peak of H2 after 90 min were enrolled as controls. 72% (33/46) of the group with an early peak showed an accelerated, 17% (8/46) a normal and 11% (5/46) a delayed OCTT. Meanwhile, in control group 40.4% (19/47) showed a normal, 57.5% (27/47) a delayed and just 1 pts an accelerated OCTT. The specificity and sensibility of LBT for an accelerated OCTT were 97.9% and 71.7% respectively. The positive predictive value of LBT for an accelerated OCTT is 97.1%;the negative predictive value is 78%. There is a significant correlation between LBT and OCTT (p The presence of an early peak of H2 between 30 and 90 min after the ingestion of 25 gr of lactose could predict the presence of an accelerated OCTT in 97% of pts. If confirmed by further study, in this subset of pts, lactulose breath test for evaluating OCTT could be avoided.
文摘The oxidations of D-fructose and D-lactose were monitored spectrophotometrically by potassium permanganate in acidic medium at λmax 545 nm. Reaction demonstrated that the two oxidative species of permanganate were involved in an acidic oxidation of the sugars. It was established that respective acids of sugars as well as arabinonic and formic acid were the oxidation products. Respective acids of sugars were the results of reactive oxygen species of permanganate ions in acidic conditions while arabinonic and formic acids due to the cleavage of C__C bond through MnO-4 species. It was first order kinetics with respect to [MnO-4 ], [fructose], [lactose] and [H+]. Hg was used to accelerate the slow oxidation of lactose. Effect of varying salt electrolyte concentration was insignificant showing that the molecular species was involved in the rate determining step. Formic and arabinonic acids and respective acids were analyzed through spot and spectroscopic studies respectively. Reaction was monitored at different temperatures and thermodynamics activation parameters were determined. A mechanism consistent with kinetic studies, spectral evidences, stoichiometry of the reactions and product analysis has been proposed for the oxidation of fructose and lactose in absence and presence of catalyst respectively.
文摘BACKGROUND Lactose malabsorption is variably associated with lactose intolerance (LI). The determinants of symptom onset have not yet been completely identified. Visceral sensitivity may play a role in the pathogenesis of functional symptoms;an increasing bulk of clinical and research data suggests the importance of the brain-gut interaction in intestinal bowel syndrome. AIM: To assess the impact of anxiety on LI symptoms, and the correlation between gas production during Lactose Breath test (LBT) and the intensity of gastrointestinal symptoms (GI) in anxious (A) and non-anxious (NA) patients. METHODS: LBT was carried out in 104 consecutive participants referred to our Gastroenterology Unit. GI symptoms were evaluated using the visual analogue scale (VAS: 0-10) throughout the LBT. All patients completed the HADS to determine anxiety. RESULTS LBT was positive in 70/104 (67%) participants;49/ 104 (47%) showed significant anxiety symptoms (>10 items). In A subjects we did not find any significant correlation between gas levels and abdominal LI symptoms scores throughout the LBT. A subject showed higher scores for all LI symptoms as compared with other participants, independently of LBT results. NA pts with positive LBT showed higher scores for all LI symptoms, as compared to negative subjects. LIMITATIONS: The predominant gender is female but it is in agreement with literature data that show a preponderance of IBS in women. CONCLUSIONS: A status significantly influences the severity of all LI symptoms and does not strictly correlate with lactase deficiency. Conversely, among NA subjects LI symptoms increase along with H2 production. Anxiety seems to be a confounding factor in IBS pts.
文摘Lactose, the sugar naturally present in milk, provides energy to lactic acid bacteria used in fermented dairy foods. Increasing concentrations of lactose may improve survivability of lactic acid bacteria in the dairy foods and in human gut enhancing their probiotic benefits. Acid tolerance is an important probiotic characteristic. The objective was to determine the influence of lactose on acid tolerance of yogurt starter culture </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Streptococcus thermophiles</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> ST-M5 and </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lactobacillus bulgaricus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> LB-12. The M 17 broth was used for </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Streptococcus thermophiles</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:""><span style="font-family:Verdana;"> ST-M5 and MRS broth was used for</span><i> </i></span><i><span style="font-family:Verdana;"><i></span></i><i><span style="font-family:Verdana;">Lactobacillus bulgaricus</span></i><i><span style="font-family:Verdana;"></i></span></i><i><span style="font-family:""> </span></i><span style="font-family:""><span style="font-family:Verdana;">LB-12</span><i><span style="font-family:Verdana;">.</span></i><span style="font-family:Verdana;"> Lactose was added to both broths at 0% (control), 1%, 3%, and 5% (wt/vol). Both broths were acidified to pH 2.0. Upon sterilizing and tempering, both broths were inoculated. Acid tolerance </span></span><span style="font-family:Verdana;">was </span><span style="font-family:Verdana;">determined as viable counts in acidified broths after 120 minutes of incubations. In an incubation period of 2 hours, dilutions were plated every 30 minutes. Three replications were conducted. The highest acid tolerance for </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Streptococcus thermophiles</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> ST-M5 and </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">Lactobacillus bulgaricus</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;"> LB-12, was observed in lactose concentration of 3% and 5% (wt/vol).
文摘<span style="font-size:14px;">Due to the widespread use of antibiotics, the bad ecological situation, fer</span><span style="font-size:14px;" "="">mented milk drinks are gaining more and more popularity because of associating with an array of health benefits. Fermented milk products contain a unique in its kind disaccharide of animal origin lactose, which has the ability to stimulate the development of lactic acid microorganisms that suppress the vital activity of pathogenic microflora in the human intestine, promoting the absorption of calcium, magnesium and phosphorus.</span><span style="font-size:10.0pt;font-family:;" "=""> </span><span style="font-size:10.0pt;font-family:;" "=""><span style="font-size:14px;">A significant part of the </span><span style="font-size:14px;">world’s population suffers from lactose intolerance, linked to a genetically</span> <span><span style="font-size:14px;">determined deficiency of the </span><i><span style="font-size:14px;">β</span></i><span style="font-size:14px;">-galactosidase enzyme, which is one of the</span></span><span style="font-size:14px;"> main reasons for the decrease in demand for dairy products among consumers suffering from primary or acquired intolerance to milk sugar.</span></span><span style="font-size:10.0pt;font-family:;" "=""> </span><span style="font-size:14px;" "="">Lactose is a natural disaccharide contained in dairy products. Lactase deficiency is a variant of fermentopathy caused by the inability to break down lactose due to the activity decrease of lactase—the parietal digestion enzyme in the small intestine. Lactose intolerance in the gastrointestinal tract of a person suffering from hypo- and alactasia leads to dispersion, diarrhea and other undesirable phenomena. For the successful prevention and treatment of these diseases, it is necessary to reduce or completely eliminate the lactose intake.</span><span style="font-size:10.0pt;font-family:;" "=""> </span><span style="font-size:14px;" "="">A technology for lactose-free milk production was developed using fermentation technology. On the basis of lactose-free milk, a range of lactose-free yoghurts was developed of animal origin of the following types: natural, enriched and fortified. Flax seeds, sesame seeds and chia seeds, which are rich in vitamins, were used to produce a range of enriched yogurts. To obtain fortified yoghurts, the mineral iron was used, which prevent the development of anemia and oncological pathologies. Experimental assortment of lactose-free yoghurts was assessed by physicochemical and organoleptic methods. All developed samples meet the standards of technical documentation for this type of food product. The organoleptic characteristics were highly appreciated. Developed lactose-</span><span style="font-size:14px;" "="">free products are an opportunity for many people to return to a normal</span><span style="font-size:14px;" "=""> healthy diet.</span>
文摘Lactose intolerance is becoming a health state that requires the restriction of dairy products in the diet of people suffering from this condition. But milk and dairy products, due to a well-balanced composition in the main macro and micronutrients, cannot be missing from the diet of the consumer of any age. For these reasons, in recent years, in the milk processing industry, the production of low-lactose or lactose-free dairy products is explored. To reduce the lactose content of dairy raw materials, various industrial and biotechnological methods were used: enzymatic hydrolysis of lactose, baromembranous methods, bioconversion of lactose by lactic bacteria and others. The most widely used lactase enzymes in the industry are mesophilic enzymes from filamentous fungi <span>(<i>Aspergillus</i> <i>spp</i>.)</span> and yeasts <span>(<i>Kluyveromyces</i> <i>spp</i>.). </span>Therefore, the aim of this study was to evaluate the effect of the commercial enzyme <i>β</i>-galactosidase on the hydrolysis of cow’s milk at different enzyme <span>con</span><span>centrations, temperatures and pH. Two commercial enzymes <i>β</i>-galactosi</span><span>dase</span> obtain<span>ed from <i>Bacillus</i><span> <i>licheniformis</i></span> and <i>β</i>-galactosidase obtained from <i>Kluyve</i></span><i>romyces</i><span> <i>lactis</i></span>, were used in this study, according to information provided by the manufacturer. The thermal stability of lactose, the effect of milk pH, the effect of temperature, duration of hydrolysis and the amount of enzymes on the lactose hydrolysis degree and the sweetness degree of milk were determined. Research has identified the optimal parameters for obtaining a high degree of lactose hydrolysis in the use of these enzymes. Therefore, to ensure a high lactose hydrolysis degree (over 80%), the following lactose hydrolysis regimens were identified: temperature 4°C - 6<span style="white-space:normal;">°</span>C, 0.3% <i>Bacillus</i><span> <i>licheniformis</i></span> enzymes, duration 4 hours;temperature 4<span style="white-space:normal;">°</span>C - 6<span style="white-space:normal;">°</span>C, 0.3% enzymes from <i>Klavyromyces</i><span> <i>lactis</i></span>, duration 12 hours and temperature 38<span style="white-space:normal;">°</span>C - 40<span style="white-space:normal;">°</span>C, 0.15% enzymes from (<i>Bacillus</i><span> <i>licheniformis</i></span> or <i>Klavyromyces</i><span> <i>lactis</i></span>), duration 2 - 3 hours. The results obtained allow the efficient use of <i>Bacillus</i><span> <i>licheniformis</i></span> and <i>Klavyromyces</i><span> <i>lactis</i></span> enzymes in industrial processes for the manufacture of “lactose-free” or “low-lactose” drinking milk and fermented dairy products for people with lactose intolerance.
文摘The lactose-fermenter Enterobacteriaceae are the most frequent cause of clinical infection in our country. The objective of this study was to isolate and identify the most common lactose-fermenter Enterobacteriaceae from clinical samples, including urine, blood, wounds, and sputum, obtained from the local hospital and from environmental samples from a chicken farm, agriculture soil, and water from the Tigris River in Baghdad City. The study also aimed at establishing the antibiotic resistance patterns of the isolated bacteria. A total of 155 bacterial isolates were identified from 10 genera according to the Vitek 2 system. The most common bacterial isolates from the clinical and environmental samples were Escherichia coli and Klebsiella pneumoniae, respectively. The antibiotic resistance patterns showed that all clinical and environmental isolates were multidrug resistant to β-lactam (except carbapenems) drug and aminoglycosides and more sensitive to carbapenems.
