The application of microorganisms as probiotics is limited due to lack of safety evaluation.Here,a novel multi-stress-tolerant yeast Meyerozyma guilliermondii GXDK6 with aroma-producing properties was identified from ...The application of microorganisms as probiotics is limited due to lack of safety evaluation.Here,a novel multi-stress-tolerant yeast Meyerozyma guilliermondii GXDK6 with aroma-producing properties was identified from marine mangrove microorganisms.Its safety and probiotic properties were assessed in accordance with phenotype and whole-genome sequencing analysis.Results showed that the genes and phenotypic expression of related virulence,antibiotic resistance and retroelement were rarely found.Hyphal morphogenesis genes(SIT4,HOG1,SPA2,ERK1,ICL1,CST20,HSP104,TPS1,and RHO1)and phospholipase secretion gene(VPS4)were annotated.True hyphae and phospholipase were absent.Only one retroelement(Tad1-65_BG)was found.Major biogenic amines(BAs)encoding genes were absent,except for spermidine synthase(JA9_002594),spermine synthase(JA9_004690),and tyrosine decarboxylase(inx).The production of single BAs and total BAs was far below the food-defined thresholds.GXDK6 had no resistance to common antifungal drugs.Virulence enzymes,such as gelatinase,DNase,hemolytic,lecithinase,and thrombin were absent.Acute toxicity test with mice demonstrated that GXDK6 is safe.GXDK6 has a good reproduction ability in the simulation gastrointestinal tract.GXDK6 also has a strong antioxidant ability,β-glucosidase,and inulinase activity.To sum up,GXDK6 is considered as a safe probiotic for human consumption and food fermentation.展开更多
AIM:To investigate the risk factors for liver-related mortality in chronic hepatitis C(CHC)patients.METHODS:All deceased CHC inpatient data were collected from the Beijing 302 Hospital clinical database,which includes...AIM:To investigate the risk factors for liver-related mortality in chronic hepatitis C(CHC)patients.METHODS:All deceased CHC inpatient data were collected from the Beijing 302 Hospital clinical database,which includes more than 8250 CHC inpatients during the period from 2002 to 2012.The controls were matched to cases by age(±2 years),sex and date of hospital admission(within the same year).Potential risk factors were included for the evaluation,and odds ratios(OR)and 95%CI were estimated using univariate(unadjusted)and multivariate(adjusted OR,AOR)conditional logistic regression.All statistical tests were two-sided.P values<0.05 were considered statistically significant.RESULTS:Based on examinations of 144 CHC-related deceased cases and 576 controls,we found that antiviral therapy with interferon-αwas associated with a 47%decrease in the risk of hepatic mortality(AOR=0.53,95%CI:0.28-0.99,P=0.048).Additionally,the initial diagnostic stage of the disease(AOR=2.89,95%CI:1.83-4.56 and P<0.001 for liver cirrhosis/AOR=8.82,95%CI:3.99-19.53 and P<0.001for HCC compared with CHC),diabetes(AOR=2.35,95%CI:1.40-3.95,P=0.001),hypertension(AOR=1.76,95%CI:1.09-2.82,P=0.020),alcohol consumption(AOR=1.73,95%CI:1.03-2.81,P=0.037)and HBsAg positivity(AOR=22.28,95%CI:5.58-89.07,P<0.001)were associated with a significant increase in the risk of liver-related mortality in CHC patients.CONCLUSION:This study indicates that interferon-αtreatment,the stage at the initial diagnosis of the disease and comorbidities are all independent risk factors for liver-related mortality in CHC patients.展开更多
Water purification with Moringa oleifera seeds has received a lot of attention because it reduces water turbidity and pathogenic microorganisms. However, it is important to define the optimum conditions of storage to ...Water purification with Moringa oleifera seeds has received a lot of attention because it reduces water turbidity and pathogenic microorganisms. However, it is important to define the optimum conditions of storage to preserve the treated water quality. The study aims to investigate microbial quality of water treated with Moringa oleifera seeds or cake coagulants in relation to the storage temperature and shelf life in order to define the optimum conditions of storage. A total of 45 water samples from 3 water reservoirs of Loumbila, Ziga and Ouaga 3 dams were collected in sterile glass bottles and treated in triplicate with Moringa oleifera seeds or defatted cakes coagulants. Treated water samples obtained at optimum conditions were stored at room temperature (25°C - 30°C) and at 4°C. Fecal bacteria pollution indicators (Escherichia coli, fecal coliforms and fecal streptococcus) and parasites were monitored every 24 hours during three (3) days based on laboratory standard methods. Data were analyzed using the Student’s t-test and XLSTAT 7.5.2 statistical software. From the results obtained, bacterial indicators increased significantly with storage temperature (p and shelf life (p . However, for all water samples, bacterial growth was more important in samples treated with Moringa oleifera cakes than seeds (p . For water samples treated with Moringa oleifera seeds and stored at room temperature, bacterial increase after 72 hours was 57 - 80, 42 - 50 and 22 - 47 CFU/100 ml for fecal coliforms, E. coli and fecal streptococcus, respectively. With Moringa oleifera cake’s treatment, the increase was 63 - 104, 57 - 82 and 28 - 52 for the same indicators, respectively. Bacterial growth was also more important at room temperature than at 4°C. Thus, microbiological quality of water treated with Moringa oleifera seeds was better than cakes whatever storage temperature and shelf life. Overall, water treated with Moringa oleifera seeds should be stored at low temperature and consumed within 24 hours.展开更多
Cancer immunotherapy,exemplified by the remarkable clinical benefits of the immune checkpoint blockade and chimeric antigen receptor T-cell therapy,is revolutionizing cancer therapy.They induce long-term tumor regress...Cancer immunotherapy,exemplified by the remarkable clinical benefits of the immune checkpoint blockade and chimeric antigen receptor T-cell therapy,is revolutionizing cancer therapy.They induce long-term tumor regression and overall survival benefit in many types of cancer.With the advances in our knowledge about the tumor immune microenvironment,remarkable progress has been made in the development of small-molecule drugs for immunotherapy.Small molecules targeting PRR-associated pathways,immune checkpoints,oncogenic signaling,metabolic pathways,cytokine/chemokine signaling,and immune-related kinases have been extensively investigated.Monotherapy of smallmolecule immunotherapeutic drugs and their combinations with other antitumor modalities are under active clinical investigations to overcome immune tolerance and circumvent immune checkpoint inhibitor resistance.Here,we review the latest development of small-molecule agents for cancer immunotherapy by targeting defined pathways and highlighting their progress in recent clinical investigations.展开更多
Combination therapy with peginterferon (pegIFN)-α and ribavirin (RBV) has been the standard of care (SOC) for chronic hepatitis C. Unfortunately, not all patients can achieve a sustained virologic response (SVR) with...Combination therapy with peginterferon (pegIFN)-α and ribavirin (RBV) has been the standard of care (SOC) for chronic hepatitis C. Unfortunately, not all patients can achieve a sustained virologic response (SVR) with this regimen. SVR rates are approximately 80% in patients with hepatitis C virus (HCV) genotype 2, 3, 5 and 6 and 40%-50% in patients with genotype 1 and 4. Therefore, strategies to improve SVR rates have been an important issue for clinical physicians. Several direct acting antiviral agents (DAAs) have significantly higher SVR rates when combined with pegIFN-α and RBV than pegIFN-α and RBV alone. Treatments containing DAAs have several advantages over the previous SOC, including higher specificity and efficacy, shorter treatment durations, fewer side effects, and oral administration. Based on these advantages, treatment with pegIFN-α and RBV plus telaprevir or boceprevir has become the current SOC for patients with genotype 1 HCV infection. However, many patients are either not eligible for therapy or decline treatment due to coexisting relative or absolute contraindications as well as an inability to tolerate the hematological side effects and adverse events caused by the new SOC. These factors have contributed to the advent of pegIFN-α-free regimens. The newest therapeutic regimens containing sofosbuvir and ABT-450 have shown promising results. In this review, we summarize the development of anti-HCV agents and the clinical efficacy of sofosbuvir and ABT-450-based therapies as well as the potential for future HCV studies.展开更多
AIM: To investigate the incidence, characteristics, and risk factors for hepatocellular carcinoma(HCC) in Chinese patients with primary biliary cirrhosis(PBC).METHODS: We reviewed the data of 52 PB Cassociated HCC pat...AIM: To investigate the incidence, characteristics, and risk factors for hepatocellular carcinoma(HCC) in Chinese patients with primary biliary cirrhosis(PBC).METHODS: We reviewed the data of 52 PB Cassociated HCC patients treated at Beijing 302 Hospital from January 2002 to December 2013 and analyzed its incidence and characteristics between the two genders. The risk factors for PBC-associated HCC were analyzed via a case-control study comprising 20 PBC patients with HCC and 77 matched controls without HCC. The matched factors included gender, age, follow-up period and Child-Pugh scores. Conditional logistic regression was used to evaluate the odds ratios of potential risk factors for HCC development. A P < 0.05 was considered statistically significant. RESULTS: The incidence of HCC in Chinese PBC patients was 4.13%(52/1255) and was significantly higher in the males(9.52%) than in the females(3.31%). Among the 52 PBC patients with HCC, 55.76%(29/52) were diagnosed with HCC and PBC simultaneously, and 5.76%(3/52) were diagnosed with HCC before PBC. The males with PBC-associated HCCwere more likely than the females to have undergone blood transfusion(18.75% vs 8.33%, P = 0.043), consumed alcohol(31.25% vs 8.33%, P = 0.010), smoked(31.25% vs 8.33%, P = 0.010), had a family history of malignancy(25% vs 5.56%, P = 0.012), and had serious liver inflammation, as indicated by the elevated levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase(P < 0.05). Conditional logistic regression analysis revealed that body mass index(BMI) ≥ 25 [adjusted odds ratio(AOR) = 1.116, 95%CI: 1.002-1.244, P = 0.045] and history of alcohol intake(AOR = 10.294, 95%CI: 1.108-95.680, P = 0.040) were significantly associated with increased odds of HCC development in PBC patients. CONCLUSION: HCC is not rare in Chinese PBC patients. Risk factors for PBC-associated HCC include BMI ≥ 25 and a history of alcohol intake. In addition to regular monitoring, PBC patients may benefit from abstinence from alcohol and body weight control.展开更多
Iron toxicity is one of the main edaphic constraints that hamper rice production in West African savanna and forest lowlands. Although chemical reduction processes of various types of pedogenic iron oxides could not b...Iron toxicity is one of the main edaphic constraints that hamper rice production in West African savanna and forest lowlands. Although chemical reduction processes of various types of pedogenic iron oxides could not be underestimated, the bulk of these processes can be ascribed to the specific activity of Iron-Reducing Bacteria (IRB). The reducing conditions of waterlogged lowland soils boost iron toxicity through the reduction of almost all iron into ferrous form (Fe2+), which can cause disorder in rice plant and crop yield losses. Aiming to contribute at the improvement of rice yield in Africa, an experiment was developed to evaluate the impact of subsurface drainage on IRB dynamics and activity during rice cultivation. Twelve concrete microplots with a clay-loam soil and a rice variety susceptible to iron toxicity (FKR 19) were used for the experiment. Soil in microplots was drained for 7 days (P1), 14 days (P2), and 21 days (P3), respectively. Control (T) microplots without drainage were prepared similarly. The evolution of IRB populations and the content of ferrous iron in the paddy soil and in soil near rice root were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. Data obtained were analyzed in relation to drainage frequency, rice growth stage, and rice yield using the Student t test and XLSTAT 7.5.2 statistical software. From the results obtained, the subsurface drainage reduced significantly IRB populations (p = 0.024). However, the drainage did not affect significantly ferrous iron concentration in the soil near rice roots (p = 0.708). The concentration of ferrous iron (p < 0.0001) in soil near rice roots and the number of IRB (p < 0.0001) were significantly higher during the rice tillering and maturity stages. Although no significant difference was observed for rice yield among treatments (p = 0.209), the P2 subsurface drainage showed the highest yield and the lowest concentration of ferrous iron in soil near rice roots.展开更多
Lubricants are very often found in nature under waste-oil forms and represent for the environment a real danger of pollution due to the difficulty of their biodegradation. The situation is especially worrying in most ...Lubricants are very often found in nature under waste-oil forms and represent for the environment a real danger of pollution due to the difficulty of their biodegradation. The situation is especially worrying in most developing countries in particular those of Sub-Saharan Africa due to the absence of regulation or control. The present work aims to isolate bacterial strains able to degrade hydrocarbons which can later be used in biotechnology for environments depollution. Oil-contaminated wastewater samples were collected in Ouagadougou city (Burkina Faso) and then used as source of bacterial isolation. Appropriate amounts of samples were inoculated to a mineral salt medium (MS) with Total Quartz 9000 oil as sole carbon and energy source and then incubated for enrichment, prior to microbe isolation. Two bacterial strains namely S2 and S7 were isolated from the enrichment cultures. The strains were tested for their ability to degrade other hydrocarbons (i.e. gasoline, diesel oil, brake oil) and for temperature, pH and salt concentration ranges for growth before their biochemical characteristics were defined. Based on their morphological, physiological and biochemical traits, strains S2 and S7 belong to Acinetobacter and Pseudomonas genera, respectively.展开更多
[Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis( Bt) 00-50-5 strain against Trichoplusia ni Hubner.[Method] The crystals and spores of B.thuringiensis 00-50-5 strain w...[Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis( Bt) 00-50-5 strain against Trichoplusia ni Hubner.[Method] The crystals and spores of B.thuringiensis 00-50-5 strain were first isolated and purified,and their insecticidal activities against T.ni were compared.[Result] Either the mixture of pure crystals and pure spores of 00-50-5 strain,or only pure crystals could kill T.ni larvae under the concentration of 100μg/mL after 48 h,and the mortality rate reached 100%;pure spores could not kill the larvae.Determination results of median lethal concentration showed that insecticidal activity of pure crystal of Bt 00-50-5 strain( LC50=0.32 μg/mL) was higher than the mixture of crystals and spores( LC50=0.48),but the insecticidal activity of pure spores was very low( LC50> 500.00).Therefore,the crystals were primarily responsible for causing death of larvae.[Conclusion] The paper provides theoretical basis for application of Bt 00-50-5 strain.展开更多
[Objective]This study aimed to confirm the roles of cell wall degrading enzymes (CWDEs) produced by Botryodiplodia theobromae Pat.in the infection of mango fruits. [Method] Change of activities of five types of CWDEs ...[Objective]This study aimed to confirm the roles of cell wall degrading enzymes (CWDEs) produced by Botryodiplodia theobromae Pat.in the infection of mango fruits. [Method] Change of activities of five types of CWDEs produced by B. theobromae Pat.were studied under both in vitro culture and inoculation conditions,along with the pathogenicity and the ability of producing CWDEs of four post-harvest fungal pathogens(B. theobromae Pat.,Colletotrichum gloeosporioides Penz. ,Phomopsis mangiferae Ahmad and Dothiorella dominicana Pet. et Cif.) which cause stem-end rot of mangoes. [Result]B. theobromae Pat. was able to produce polygalacturonase(PG),pectinmethylgalacturonase(PMG),polygalacturonic acid trans-eliminase (PGTE),pectin methyltrans-eliminase (PMTE) and cellulase (Cx.) under both in vitro culture and inoculation conditions,of which activities of PG,Cx and PMG were significantly higher in than that in either PGTE or PMTE. Among three primary CWDEs,the peak of activities of PG and Cx appeared earlier and that of PMG occured later. The pathogenicity of B. theobromae Pat. was significantly higher than that of any other three pathogens;it is the same with the abilities of producing pectinase.[Conclusion]This paper provides theoretical bases for further exploring the mechanism of host-pathogen interaction and decreasing the post-harvest loss of mango fruits.展开更多
This work was aimed to study of fungicidal activity and mechanism of action of the killer toxin of Cryptococcus pinus VKM Y-2958. A killer-toxin preparation was obtained and partly purified from the culture liquid of ...This work was aimed to study of fungicidal activity and mechanism of action of the killer toxin of Cryptococcus pinus VKM Y-2958. A killer-toxin preparation was obtained and partly purified from the culture liquid of the yeast Cryptococcus pinus. Its fungicidal activity against the pathogenic yeast Filobasidiella neoformans was assessed by assay of target cells growth inhibition and propidium iodide staining. The preparation contained three peptides with molecular masses of about 11 - 13 kDa, which did not show similarities in the mass spectrometric analysis. When frozen, the killer-toxin preparation remained active for several years. The killer toxin of Cr. pinus exhibits the high fungicidal activity against the known pathogen F. neoformans, is stable during long-term storage, and its mechanism of action is based on damaging target cell membranes. The killer toxin was obtained by a simple procedure and is of interest for the development of novel fungicidal preparations.展开更多
Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development, particularly in rural and periurban areas of Burkina Faso. The study aims to investigate the ...Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development, particularly in rural and periurban areas of Burkina Faso. The study aims to investigate the purifying capacity of Moringa oleifera defatted cake as compared to Moringa oleifera seed in the treatment of surface and well waters used for populations alimentation. A total of 90 water samples were collected in sterile glass bottles from 3 dams’ water reservoirs, a river, and a large diameter well, respectively. The water samples were treated in triplicate with Moringa oleifera seed and defatted cake coagulants. At different settling time and coagulant concentration, turbidity and pH were measured to determine the optimal conditions and factors influencing treatment with regard to sampling source. Nine physicochemical parameters (turbidity, pH, nitrates, nitrites, calcium, magnesium, total hardness, organic matter and sulfates), three bacterial fecal pollution indicators (Escherichia coli, fecal Coliforms and fecal Streptococcus) and parasite cysts were monitored based on laboratory standard methods. Data were analyzed using the Student’s t test and XLSTAT 7.5.2 statistical software. From the results obtained, for the same concentration of coagulant, settling time providing the lowest turbidity was significantly shorter (p Moringa oleifera cake than seed. Optimum settling time with Moringa oleifera cake was between 15 - 60 min versus 60 - 120 min, with Moringa oleifera seed. Both treatments significantly reduced minerals concentration in water excepted sulfates for which the concentration reversely increased. However, only Moringa oleifera cake treatment reduced organic matter content in all the water samples, while it increased with Moringa oleifera seed one (p < 0.0001). The reduction of microbial pollution indicators was 92% - 100% with M. oleifera cake treatment and 84% - 100% with M. oleifera seed one. Overall, for all water samples, Moringa oleifera cake treatment appeared more efficient in improving drinking water quality than the M. oleifera seed treatment.展开更多
The use in agriculture of excreta from urine-diversion toilets can be an alternative solution to the lack of sanitation and high costs of mineral fertilizers inherent to developing countries. The objective of this stu...The use in agriculture of excreta from urine-diversion toilets can be an alternative solution to the lack of sanitation and high costs of mineral fertilizers inherent to developing countries. The objective of this study was to evaluate the hygienic quality of urine used as fertilizer through an ecological sanitation system in Ouagadougou peri-urban areas. Chemical and microbiological analyses were performed in urine samples taken before and after thirty (30) days of storage in jerry cans exposed to sunlight. The concentrations of 7.0 g/l;3.5 and 9.6 g/l of ammonia nitrogen for mean, minimum and maximum respectively, are obtained in unstored urine samples. These concentrations did not practically vary with the storage. On average, values of other chemical parameters analyzed in stored urine were as follows: pH, 8.8;phosphorus (P), 0.3 g/l;potassium (K), 1.9 g/l;total dissolved solids (TDS), 21.0 g/l;cadmium (Cd), 154.3 μg/l;copper (Cu), 5.2 μg/l;lead (Pb), 15.2 μg/l;chromium (Cr), 6.1 μg/l;nickel (Ni), 154.0 μg/l. Escherichia coli, staphylococci, enterococci, Salmonella and spores of Clostridium perfringens were detected in unstored urine samples, with 26% of fecal contamination rate. The time of storage (30 days) under sunlight was enough for almost all bacteria removal in urine samples. Although the fertilizing value of urine was confirmed, it would be important to take account of the best practices on applying in soils, because of the high TDS contents. Also, the risk linked to micropollutants in urine-based fertilizers could be negligible in view of low quantities. The results obtained in this study prove that after 30 days of exposure to sunlight urine collected via eco-toilet becomes bacteriologically sanitized, and can therefore be used to fertilize soils. However, it is necessary to demonstrate the inactivation of other groups of enteric microorganisms in human urine during storage.展开更多
Sulfide toxicity is a common disease generally associated with iron toxicity which occurs in rice fields when the Sulfate-Reducing Bacteria (SRB) produce sulfides ions in anaerobic conditions. The high quantity of sul...Sulfide toxicity is a common disease generally associated with iron toxicity which occurs in rice fields when the Sulfate-Reducing Bacteria (SRB) produce sulfides ions in anaerobic conditions. The high quantity of sulfides ions in the soil solution upsets the mineral element balance in the rice, affects its growth and causes crop yield losses. In Burkina Faso, many rice field soils are abandoned due to sulfides toxicity. The present study was developed to evaluate the impact of subsurface drainage on SRB dynamics and activity during rice cultivation and the incidence on rice production. Twelve concrete microplots with a clay-loam soil and a rice variety susceptible to sulfides toxicity (FKR 19) were used for the experiment. Soil in microplots was drained for 7 days (P1), 14 days (P2), and 21 days (P3), respectively. Control (T) microplots without drainage were prepared similarly. The evolution of SRB populations and the content of sulfides ions in the paddy soil and in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. Data obtained were analyzed in relation to drainage frequency, rice growth stage, and rice yield using the Student’s t-test and XLSTAT 7.5.2 statistical software. From the results obtained, the subsurface drainage did not affect significantly SRB populations (P = 0.187). However, the drainage affected significantly sulfides concentration in the soil near rice roots (P = 0.032). The concentration of sulfides (P < 0.0001) in soil near rice roots and the number of SRB (P < 0.0001) were significantly higher during the rice tillering and maturity stages. Although no significant difference was observed for rice yield among treatments (P = 0.209), the P2 subsurface drainage showed the highest yield and a low concentration of sulfides in soil near rice roots.展开更多
Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development. The study aims to investigate the drinking water quality and the factors affecting this quali...Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development. The study aims to investigate the drinking water quality and the factors affecting this quality in the Sourou valley in Burkina Faso. A total of 135 water samples were collected in sterile glass bottles during the dry seasons 2007, 2008, and 2012 from 10 drillings and 5 wells. Fifteen physicochemical parameters and two fecal pollution indicators (Escherichia coli and fecal Coliforms) were monitored based on laboratory standard methods. Datas were analyzed, using the Student t’ test and XLSTAT 7.5.2 statistical software. From results obtained, water quality was related to water source and sampling period as well (p 0.0001). 30% of drillings provided water with nitrates concentration over the World Health Organization (WHO) guideline value. High turbidity was also observed for some drillings. Moreover, 90% of drillings showed water total hardness largely over the WHO threshold value. Water from drillings were exempt of fecal pollution, contrasting with the wells one which appeared uniformly polluted with concentrations exceeding sometimes 103 and 104 CFU/100 ml for E. coli and fecal Coliforms, respectively. Field investigations showed a preference of wells as drinking water source, and that appeared related to the lack of self-management of drillings and to cultural considerations. Overall, this study highlighted that a regular survey of water quality, management of protection zones around drinking water sources, sensitization on water resources self-management, hygiene and health issues, and providing appropriate household disinfection methods could help advancing to reach an effective safe drinking water access for rural populations in the country.展开更多
Environmental pollution with petroleum and petrochemical products such as diesel and used oils has been recognized as one of the most serious current problem in the world, especially in developing countries. These pet...Environmental pollution with petroleum and petrochemical products such as diesel and used oils has been recognized as one of the most serious current problem in the world, especially in developing countries. These petrochemical products devastate the soil, surface and underground waters and alter the microbial population at the polluted sites. Thus, the present work aims to optimize the biodegradation of diesel and two used oils (SAE 40 and SAE 50) by bacterial strains namely Acinetobacter S2 and Pseudomonas S7 using either nutrient factors (yeast extract, peptone or trace elements) or surfactants (tween 80 or Sodium Dodecyl Sulfate: SDS). The strains are incubated alone or together with the used oils or diesel supplemented or not with nutrient factors or surfactants for 14, 28, 42 and 56 days, respectively. For all the incubation period, the hydrocarbons degradation rates are determined by gravimetric assay. The results obtained show that nutrient factors increase significantly SAE 50 used oil biodegradation (p = 0.009). Similarly, tween 80 increases SAE 50 and SAE 40 used oils biodegradation but not diesel one. The results also show a significant difference between biodegradation rates at 14, 28, 42 and 56 days for all the hydro-carbons tested (p Acinetobacter S2 and Pseudomonas S7 increases the degradation over the one of the strains alone.展开更多
Rice is one of the staple crops in Burkina Faso. However, the local production covers only 47% of the population demands. One of the main reasons of the poor productivity in Burkina Faso is iron toxicity which is rela...Rice is one of the staple crops in Burkina Faso. However, the local production covers only 47% of the population demands. One of the main reasons of the poor productivity in Burkina Faso is iron toxicity which is related mainly to the activity of Iron Reducing Bacteria in the rice field’s ecosystems. In order to control the harmful effects of Iron Reducing Bacterial populations and to improve rice productivity, a pots experiment was conducted at the experimental site of the University Ouaga I Pr. Joseph KI-ZERBO. An iron toxic soil from Kou Valley (West of Burkina Faso) and two rice varieties, BOUAKE-189 and ROK-5, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were drained for 14 days (D2) and amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complexes). Control pots without drainage and fertilization (D0/NF) were prepared similarly. The kinetics of Iron Reducing Bacterial populations and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using a spectrometric method. Data obtained were analyzed in relation to drainage and fertilization mode, rice growth stage and rice yield using the Student’s t-test and XLSTAT 2014 statistical software. The experiment showed that the combined application of subsurface drainage and NPK + Urea + Ca + Mg + Zn fertilization, reduced significantly the number of IRB in the soil near rice roots for both rice varieties (p = 0.050 and p = 0.020) increased the leaf tissue tolerance to excess amounts of Fe, and rice yield.展开更多
Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at t...Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at the site of the University of Ouagadougou, in pots containing an iron toxic soil from the Kou Valley (West of Burkina Faso). The experiment objective was to study the effect of mineral fertilizer on Iron Reducing Bacteria (IRB) dynamics and activity during rice cultivation, iron accumulation in rice plant and rice biomass yield under iron toxicity conditions. BOUAKE-189 and ROK-5 rice varieties, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complex). Control pots without fertilization were prepared similarly. The kinetics of IRB and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using spectrometric method. Data obtained were analyzed in relation to fertilization mode, rice growth stage and rice yield using the student’s t-test and XLSTAT 2014 statistical software. The experiment revealed that NPK + Urea and NPK + Urea + Ca + Mg + Zn fertilization, decreased significantly (p < 0.0001) the number of IRB in the soil for BOUAKE-189 rice varieties. In most pots, highest IRB densities and ferrous iron content in soil were recorded from rice tillering and flowering to maturity stages, indicating that rice plants promoted microbial processes and iron reduction in soil. From the study, the NPK + Urea amendment decreased significantly ferrous iron content (p < 0.0001) in soil near BOUAKE-189 and ROK-5 rice varieties roots relatively to control pots. However, NPK + Urea + Ca + Zn + Mg amendment increased significantly ferrous iron content (p < 0.0001) in the soil near roots, Fe accumulation in plant biomass and rice yield for the two rice varieties.展开更多
Emerging evidence has demonstrated the vital role of metabolism in various diseases or disorders.Metabolomics provides a comprehensive understanding of metabolism in biological systems.With advanced analytical techniq...Emerging evidence has demonstrated the vital role of metabolism in various diseases or disorders.Metabolomics provides a comprehensive understanding of metabolism in biological systems.With advanced analytical techniques,metabolomics exhibits unprecedented significant value in basic drug research,including understanding disease mechanisms,identifying drug targets,and elucidating the mode of action of drugs.More importantly,metabolomics greatly accelerates the drug development process by predicting pharmacokinetics,pharmacodynamics,and drug response.In addition,metabolomics facilitates the exploration of drug repurposing and drug-drug interactions,as well as the development of personalized treatment strategies.Here,we briefly review the recent advances in technologies in metabolomics and update our knowledge of the applications of metabolomics in drug research and development.展开更多
Urban truck farming in developing countries appears of great importance to overcome unemployment and poverty. However, the quality of wastewater used for such activity could expose populations to waterborne diseases. ...Urban truck farming in developing countries appears of great importance to overcome unemployment and poverty. However, the quality of wastewater used for such activity could expose populations to waterborne diseases. The microbial quality of wastewaters used for truck farming in Ouagadougou city, was examined for the presence of bacterial and parasitological fecal indicators during the dry-hot season (May) and the wet season (July) in 2012. The wastewaters of three water reservoirs and two canals intensively used for truck farming were analyzed throughout the study. These indicators were also monitored in waste stabilization ponds during wastewater treatment in 3 plants of the city. For all the selected sampling sites, the concentrations of microbial indicators in water were significantly higher in the dry-hot season compared to the wet one (p - 53,800 CFU/100ml for Escherichia coli, 8200 - 108,400 CFU/100ml for fecal coliforms, 650 - 45,000 CFU/100ml) for fecal streptococcus, and 0 - 2.4 eggs/l for helminthes during the study periods. For wastewater under treatment in waste stabilization ponds, significant microbial concentration drops (p 0.0001) in the range of 82% - 100%, 78% - 98%, 60% - 100% and 82% - 88%, respectively were recorded between the anaerobic and the maturation ponds. The later results highlighted that improving the refining performances of the waste stabilization ponds technology could help decreasing health risks related to wastewater reuse in urban agriculture for a sustainable development of cities in developing countries.展开更多
基金This research was supported by the Funding Project of Chinese Central Government Guiding to the Guangxi Local Science and Technology Development(GUIKEZY21195021)the Natural Science Fund for Distinguished Young Scholars of Guangxi Zhuang Autonomous Region of China(2019GXNSFFA245011)+3 种基金the Funding Project of Chinese Central Government Guiding to the Nanning Local Science and Technology Development(20231012)the Funding Projects of Guangxi Key Research and Development Plan(GUIKE AB23075173)the Funding Project of Technological Development from Angel Yeast(Chongzuo)Co.,Ltd.(JS1006020230722019)the Innovation Project of Guangxi Graduate Education(YCBZ2021012).
文摘The application of microorganisms as probiotics is limited due to lack of safety evaluation.Here,a novel multi-stress-tolerant yeast Meyerozyma guilliermondii GXDK6 with aroma-producing properties was identified from marine mangrove microorganisms.Its safety and probiotic properties were assessed in accordance with phenotype and whole-genome sequencing analysis.Results showed that the genes and phenotypic expression of related virulence,antibiotic resistance and retroelement were rarely found.Hyphal morphogenesis genes(SIT4,HOG1,SPA2,ERK1,ICL1,CST20,HSP104,TPS1,and RHO1)and phospholipase secretion gene(VPS4)were annotated.True hyphae and phospholipase were absent.Only one retroelement(Tad1-65_BG)was found.Major biogenic amines(BAs)encoding genes were absent,except for spermidine synthase(JA9_002594),spermine synthase(JA9_004690),and tyrosine decarboxylase(inx).The production of single BAs and total BAs was far below the food-defined thresholds.GXDK6 had no resistance to common antifungal drugs.Virulence enzymes,such as gelatinase,DNase,hemolytic,lecithinase,and thrombin were absent.Acute toxicity test with mice demonstrated that GXDK6 is safe.GXDK6 has a good reproduction ability in the simulation gastrointestinal tract.GXDK6 also has a strong antioxidant ability,β-glucosidase,and inulinase activity.To sum up,GXDK6 is considered as a safe probiotic for human consumption and food fermentation.
基金Supported by National Natural Science Foundation of China,No.81302593,No.81271848 and No.81101589the Grant of Beijing Nova Program of China,No.Z121107002512071+1 种基金the National Key Basic Research Program of China,No.2009CB522507the National Grand Program on Key Infectious Disease,No.2009ZX10005-017 and No.2012ZX10002007
文摘AIM:To investigate the risk factors for liver-related mortality in chronic hepatitis C(CHC)patients.METHODS:All deceased CHC inpatient data were collected from the Beijing 302 Hospital clinical database,which includes more than 8250 CHC inpatients during the period from 2002 to 2012.The controls were matched to cases by age(±2 years),sex and date of hospital admission(within the same year).Potential risk factors were included for the evaluation,and odds ratios(OR)and 95%CI were estimated using univariate(unadjusted)and multivariate(adjusted OR,AOR)conditional logistic regression.All statistical tests were two-sided.P values<0.05 were considered statistically significant.RESULTS:Based on examinations of 144 CHC-related deceased cases and 576 controls,we found that antiviral therapy with interferon-αwas associated with a 47%decrease in the risk of hepatic mortality(AOR=0.53,95%CI:0.28-0.99,P=0.048).Additionally,the initial diagnostic stage of the disease(AOR=2.89,95%CI:1.83-4.56 and P<0.001 for liver cirrhosis/AOR=8.82,95%CI:3.99-19.53 and P<0.001for HCC compared with CHC),diabetes(AOR=2.35,95%CI:1.40-3.95,P=0.001),hypertension(AOR=1.76,95%CI:1.09-2.82,P=0.020),alcohol consumption(AOR=1.73,95%CI:1.03-2.81,P=0.037)and HBsAg positivity(AOR=22.28,95%CI:5.58-89.07,P<0.001)were associated with a significant increase in the risk of liver-related mortality in CHC patients.CONCLUSION:This study indicates that interferon-αtreatment,the stage at the initial diagnosis of the disease and comorbidities are all independent risk factors for liver-related mortality in CHC patients.
文摘Water purification with Moringa oleifera seeds has received a lot of attention because it reduces water turbidity and pathogenic microorganisms. However, it is important to define the optimum conditions of storage to preserve the treated water quality. The study aims to investigate microbial quality of water treated with Moringa oleifera seeds or cake coagulants in relation to the storage temperature and shelf life in order to define the optimum conditions of storage. A total of 45 water samples from 3 water reservoirs of Loumbila, Ziga and Ouaga 3 dams were collected in sterile glass bottles and treated in triplicate with Moringa oleifera seeds or defatted cakes coagulants. Treated water samples obtained at optimum conditions were stored at room temperature (25°C - 30°C) and at 4°C. Fecal bacteria pollution indicators (Escherichia coli, fecal coliforms and fecal streptococcus) and parasites were monitored every 24 hours during three (3) days based on laboratory standard methods. Data were analyzed using the Student’s t-test and XLSTAT 7.5.2 statistical software. From the results obtained, bacterial indicators increased significantly with storage temperature (p and shelf life (p . However, for all water samples, bacterial growth was more important in samples treated with Moringa oleifera cakes than seeds (p . For water samples treated with Moringa oleifera seeds and stored at room temperature, bacterial increase after 72 hours was 57 - 80, 42 - 50 and 22 - 47 CFU/100 ml for fecal coliforms, E. coli and fecal streptococcus, respectively. With Moringa oleifera cake’s treatment, the increase was 63 - 104, 57 - 82 and 28 - 52 for the same indicators, respectively. Bacterial growth was also more important at room temperature than at 4°C. Thus, microbiological quality of water treated with Moringa oleifera seeds was better than cakes whatever storage temperature and shelf life. Overall, water treated with Moringa oleifera seeds should be stored at low temperature and consumed within 24 hours.
基金supported by the National Natural Science Foundation of China(Nos.U21A20421,82073882,82073317,81772540 and 82272996)the Key Project of Science Technology Program of Guangzhou(No.2023B03J0029,China)+1 种基金the National Key R&D Program of China(No.2022YFE0209700)the Science and Technology Program of Guangzhou(Nos.202201010819 and 202206010081,China)。
文摘Cancer immunotherapy,exemplified by the remarkable clinical benefits of the immune checkpoint blockade and chimeric antigen receptor T-cell therapy,is revolutionizing cancer therapy.They induce long-term tumor regression and overall survival benefit in many types of cancer.With the advances in our knowledge about the tumor immune microenvironment,remarkable progress has been made in the development of small-molecule drugs for immunotherapy.Small molecules targeting PRR-associated pathways,immune checkpoints,oncogenic signaling,metabolic pathways,cytokine/chemokine signaling,and immune-related kinases have been extensively investigated.Monotherapy of smallmolecule immunotherapeutic drugs and their combinations with other antitumor modalities are under active clinical investigations to overcome immune tolerance and circumvent immune checkpoint inhibitor resistance.Here,we review the latest development of small-molecule agents for cancer immunotherapy by targeting defined pathways and highlighting their progress in recent clinical investigations.
基金Supported by Grants from the National Key Basic Research Program of China, No. 2009CB522507, No. 2012CB519005Beijing Nova Program of China, No. Z12110702512071
文摘Combination therapy with peginterferon (pegIFN)-α and ribavirin (RBV) has been the standard of care (SOC) for chronic hepatitis C. Unfortunately, not all patients can achieve a sustained virologic response (SVR) with this regimen. SVR rates are approximately 80% in patients with hepatitis C virus (HCV) genotype 2, 3, 5 and 6 and 40%-50% in patients with genotype 1 and 4. Therefore, strategies to improve SVR rates have been an important issue for clinical physicians. Several direct acting antiviral agents (DAAs) have significantly higher SVR rates when combined with pegIFN-α and RBV than pegIFN-α and RBV alone. Treatments containing DAAs have several advantages over the previous SOC, including higher specificity and efficacy, shorter treatment durations, fewer side effects, and oral administration. Based on these advantages, treatment with pegIFN-α and RBV plus telaprevir or boceprevir has become the current SOC for patients with genotype 1 HCV infection. However, many patients are either not eligible for therapy or decline treatment due to coexisting relative or absolute contraindications as well as an inability to tolerate the hematological side effects and adverse events caused by the new SOC. These factors have contributed to the advent of pegIFN-α-free regimens. The newest therapeutic regimens containing sofosbuvir and ABT-450 have shown promising results. In this review, we summarize the development of anti-HCV agents and the clinical efficacy of sofosbuvir and ABT-450-based therapies as well as the potential for future HCV studies.
基金Supported by National Natural Science Foundation of China,No.81470837,No.81101589 and No.81302593
文摘AIM: To investigate the incidence, characteristics, and risk factors for hepatocellular carcinoma(HCC) in Chinese patients with primary biliary cirrhosis(PBC).METHODS: We reviewed the data of 52 PB Cassociated HCC patients treated at Beijing 302 Hospital from January 2002 to December 2013 and analyzed its incidence and characteristics between the two genders. The risk factors for PBC-associated HCC were analyzed via a case-control study comprising 20 PBC patients with HCC and 77 matched controls without HCC. The matched factors included gender, age, follow-up period and Child-Pugh scores. Conditional logistic regression was used to evaluate the odds ratios of potential risk factors for HCC development. A P < 0.05 was considered statistically significant. RESULTS: The incidence of HCC in Chinese PBC patients was 4.13%(52/1255) and was significantly higher in the males(9.52%) than in the females(3.31%). Among the 52 PBC patients with HCC, 55.76%(29/52) were diagnosed with HCC and PBC simultaneously, and 5.76%(3/52) were diagnosed with HCC before PBC. The males with PBC-associated HCCwere more likely than the females to have undergone blood transfusion(18.75% vs 8.33%, P = 0.043), consumed alcohol(31.25% vs 8.33%, P = 0.010), smoked(31.25% vs 8.33%, P = 0.010), had a family history of malignancy(25% vs 5.56%, P = 0.012), and had serious liver inflammation, as indicated by the elevated levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase(P < 0.05). Conditional logistic regression analysis revealed that body mass index(BMI) ≥ 25 [adjusted odds ratio(AOR) = 1.116, 95%CI: 1.002-1.244, P = 0.045] and history of alcohol intake(AOR = 10.294, 95%CI: 1.108-95.680, P = 0.040) were significantly associated with increased odds of HCC development in PBC patients. CONCLUSION: HCC is not rare in Chinese PBC patients. Risk factors for PBC-associated HCC include BMI ≥ 25 and a history of alcohol intake. In addition to regular monitoring, PBC patients may benefit from abstinence from alcohol and body weight control.
文摘Iron toxicity is one of the main edaphic constraints that hamper rice production in West African savanna and forest lowlands. Although chemical reduction processes of various types of pedogenic iron oxides could not be underestimated, the bulk of these processes can be ascribed to the specific activity of Iron-Reducing Bacteria (IRB). The reducing conditions of waterlogged lowland soils boost iron toxicity through the reduction of almost all iron into ferrous form (Fe2+), which can cause disorder in rice plant and crop yield losses. Aiming to contribute at the improvement of rice yield in Africa, an experiment was developed to evaluate the impact of subsurface drainage on IRB dynamics and activity during rice cultivation. Twelve concrete microplots with a clay-loam soil and a rice variety susceptible to iron toxicity (FKR 19) were used for the experiment. Soil in microplots was drained for 7 days (P1), 14 days (P2), and 21 days (P3), respectively. Control (T) microplots without drainage were prepared similarly. The evolution of IRB populations and the content of ferrous iron in the paddy soil and in soil near rice root were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. Data obtained were analyzed in relation to drainage frequency, rice growth stage, and rice yield using the Student t test and XLSTAT 7.5.2 statistical software. From the results obtained, the subsurface drainage reduced significantly IRB populations (p = 0.024). However, the drainage did not affect significantly ferrous iron concentration in the soil near rice roots (p = 0.708). The concentration of ferrous iron (p < 0.0001) in soil near rice roots and the number of IRB (p < 0.0001) were significantly higher during the rice tillering and maturity stages. Although no significant difference was observed for rice yield among treatments (p = 0.209), the P2 subsurface drainage showed the highest yield and the lowest concentration of ferrous iron in soil near rice roots.
文摘Lubricants are very often found in nature under waste-oil forms and represent for the environment a real danger of pollution due to the difficulty of their biodegradation. The situation is especially worrying in most developing countries in particular those of Sub-Saharan Africa due to the absence of regulation or control. The present work aims to isolate bacterial strains able to degrade hydrocarbons which can later be used in biotechnology for environments depollution. Oil-contaminated wastewater samples were collected in Ouagadougou city (Burkina Faso) and then used as source of bacterial isolation. Appropriate amounts of samples were inoculated to a mineral salt medium (MS) with Total Quartz 9000 oil as sole carbon and energy source and then incubated for enrichment, prior to microbe isolation. Two bacterial strains namely S2 and S7 were isolated from the enrichment cultures. The strains were tested for their ability to degrade other hydrocarbons (i.e. gasoline, diesel oil, brake oil) and for temperature, pH and salt concentration ranges for growth before their biochemical characteristics were defined. Based on their morphological, physiological and biochemical traits, strains S2 and S7 belong to Acinetobacter and Pseudomonas genera, respectively.
基金supported by Project for Introduced Talents in Environment and Plant Protection Institute of Chinese Academy of Tropical Agriculture(HZS1101)Fundamental Research Special Project for Central Public-interest Scientific Institutes(2012hzs1 J038,2012hzs1 J016)
文摘[Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis( Bt) 00-50-5 strain against Trichoplusia ni Hubner.[Method] The crystals and spores of B.thuringiensis 00-50-5 strain were first isolated and purified,and their insecticidal activities against T.ni were compared.[Result] Either the mixture of pure crystals and pure spores of 00-50-5 strain,or only pure crystals could kill T.ni larvae under the concentration of 100μg/mL after 48 h,and the mortality rate reached 100%;pure spores could not kill the larvae.Determination results of median lethal concentration showed that insecticidal activity of pure crystal of Bt 00-50-5 strain( LC50=0.32 μg/mL) was higher than the mixture of crystals and spores( LC50=0.48),but the insecticidal activity of pure spores was very low( LC50> 500.00).Therefore,the crystals were primarily responsible for causing death of larvae.[Conclusion] The paper provides theoretical basis for application of Bt 00-50-5 strain.
基金Supported by the Special Fund for Agro-scientific Research(3-44-2)the Special Fund for Basic Research of Central Universities in the Public Interest,China(N0.2009hzs1J011,NO.2011hzs1J027,NO.2011hzs1J004)
文摘[Objective]This study aimed to confirm the roles of cell wall degrading enzymes (CWDEs) produced by Botryodiplodia theobromae Pat.in the infection of mango fruits. [Method] Change of activities of five types of CWDEs produced by B. theobromae Pat.were studied under both in vitro culture and inoculation conditions,along with the pathogenicity and the ability of producing CWDEs of four post-harvest fungal pathogens(B. theobromae Pat.,Colletotrichum gloeosporioides Penz. ,Phomopsis mangiferae Ahmad and Dothiorella dominicana Pet. et Cif.) which cause stem-end rot of mangoes. [Result]B. theobromae Pat. was able to produce polygalacturonase(PG),pectinmethylgalacturonase(PMG),polygalacturonic acid trans-eliminase (PGTE),pectin methyltrans-eliminase (PMTE) and cellulase (Cx.) under both in vitro culture and inoculation conditions,of which activities of PG,Cx and PMG were significantly higher in than that in either PGTE or PMTE. Among three primary CWDEs,the peak of activities of PG and Cx appeared earlier and that of PMG occured later. The pathogenicity of B. theobromae Pat. was significantly higher than that of any other three pathogens;it is the same with the abilities of producing pectinase.[Conclusion]This paper provides theoretical bases for further exploring the mechanism of host-pathogen interaction and decreasing the post-harvest loss of mango fruits.
文摘This work was aimed to study of fungicidal activity and mechanism of action of the killer toxin of Cryptococcus pinus VKM Y-2958. A killer-toxin preparation was obtained and partly purified from the culture liquid of the yeast Cryptococcus pinus. Its fungicidal activity against the pathogenic yeast Filobasidiella neoformans was assessed by assay of target cells growth inhibition and propidium iodide staining. The preparation contained three peptides with molecular masses of about 11 - 13 kDa, which did not show similarities in the mass spectrometric analysis. When frozen, the killer-toxin preparation remained active for several years. The killer toxin of Cr. pinus exhibits the high fungicidal activity against the known pathogen F. neoformans, is stable during long-term storage, and its mechanism of action is based on damaging target cell membranes. The killer toxin was obtained by a simple procedure and is of interest for the development of novel fungicidal preparations.
文摘Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development, particularly in rural and periurban areas of Burkina Faso. The study aims to investigate the purifying capacity of Moringa oleifera defatted cake as compared to Moringa oleifera seed in the treatment of surface and well waters used for populations alimentation. A total of 90 water samples were collected in sterile glass bottles from 3 dams’ water reservoirs, a river, and a large diameter well, respectively. The water samples were treated in triplicate with Moringa oleifera seed and defatted cake coagulants. At different settling time and coagulant concentration, turbidity and pH were measured to determine the optimal conditions and factors influencing treatment with regard to sampling source. Nine physicochemical parameters (turbidity, pH, nitrates, nitrites, calcium, magnesium, total hardness, organic matter and sulfates), three bacterial fecal pollution indicators (Escherichia coli, fecal Coliforms and fecal Streptococcus) and parasite cysts were monitored based on laboratory standard methods. Data were analyzed using the Student’s t test and XLSTAT 7.5.2 statistical software. From the results obtained, for the same concentration of coagulant, settling time providing the lowest turbidity was significantly shorter (p Moringa oleifera cake than seed. Optimum settling time with Moringa oleifera cake was between 15 - 60 min versus 60 - 120 min, with Moringa oleifera seed. Both treatments significantly reduced minerals concentration in water excepted sulfates for which the concentration reversely increased. However, only Moringa oleifera cake treatment reduced organic matter content in all the water samples, while it increased with Moringa oleifera seed one (p < 0.0001). The reduction of microbial pollution indicators was 92% - 100% with M. oleifera cake treatment and 84% - 100% with M. oleifera seed one. Overall, for all water samples, Moringa oleifera cake treatment appeared more efficient in improving drinking water quality than the M. oleifera seed treatment.
文摘The use in agriculture of excreta from urine-diversion toilets can be an alternative solution to the lack of sanitation and high costs of mineral fertilizers inherent to developing countries. The objective of this study was to evaluate the hygienic quality of urine used as fertilizer through an ecological sanitation system in Ouagadougou peri-urban areas. Chemical and microbiological analyses were performed in urine samples taken before and after thirty (30) days of storage in jerry cans exposed to sunlight. The concentrations of 7.0 g/l;3.5 and 9.6 g/l of ammonia nitrogen for mean, minimum and maximum respectively, are obtained in unstored urine samples. These concentrations did not practically vary with the storage. On average, values of other chemical parameters analyzed in stored urine were as follows: pH, 8.8;phosphorus (P), 0.3 g/l;potassium (K), 1.9 g/l;total dissolved solids (TDS), 21.0 g/l;cadmium (Cd), 154.3 μg/l;copper (Cu), 5.2 μg/l;lead (Pb), 15.2 μg/l;chromium (Cr), 6.1 μg/l;nickel (Ni), 154.0 μg/l. Escherichia coli, staphylococci, enterococci, Salmonella and spores of Clostridium perfringens were detected in unstored urine samples, with 26% of fecal contamination rate. The time of storage (30 days) under sunlight was enough for almost all bacteria removal in urine samples. Although the fertilizing value of urine was confirmed, it would be important to take account of the best practices on applying in soils, because of the high TDS contents. Also, the risk linked to micropollutants in urine-based fertilizers could be negligible in view of low quantities. The results obtained in this study prove that after 30 days of exposure to sunlight urine collected via eco-toilet becomes bacteriologically sanitized, and can therefore be used to fertilize soils. However, it is necessary to demonstrate the inactivation of other groups of enteric microorganisms in human urine during storage.
文摘Sulfide toxicity is a common disease generally associated with iron toxicity which occurs in rice fields when the Sulfate-Reducing Bacteria (SRB) produce sulfides ions in anaerobic conditions. The high quantity of sulfides ions in the soil solution upsets the mineral element balance in the rice, affects its growth and causes crop yield losses. In Burkina Faso, many rice field soils are abandoned due to sulfides toxicity. The present study was developed to evaluate the impact of subsurface drainage on SRB dynamics and activity during rice cultivation and the incidence on rice production. Twelve concrete microplots with a clay-loam soil and a rice variety susceptible to sulfides toxicity (FKR 19) were used for the experiment. Soil in microplots was drained for 7 days (P1), 14 days (P2), and 21 days (P3), respectively. Control (T) microplots without drainage were prepared similarly. The evolution of SRB populations and the content of sulfides ions in the paddy soil and in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. Data obtained were analyzed in relation to drainage frequency, rice growth stage, and rice yield using the Student’s t-test and XLSTAT 7.5.2 statistical software. From the results obtained, the subsurface drainage did not affect significantly SRB populations (P = 0.187). However, the drainage affected significantly sulfides concentration in the soil near rice roots (P = 0.032). The concentration of sulfides (P < 0.0001) in soil near rice roots and the number of SRB (P < 0.0001) were significantly higher during the rice tillering and maturity stages. Although no significant difference was observed for rice yield among treatments (P = 0.209), the P2 subsurface drainage showed the highest yield and a low concentration of sulfides in soil near rice roots.
文摘Safe drinking water access for rural populations in developing countries remains a challenge for a sustainable development. The study aims to investigate the drinking water quality and the factors affecting this quality in the Sourou valley in Burkina Faso. A total of 135 water samples were collected in sterile glass bottles during the dry seasons 2007, 2008, and 2012 from 10 drillings and 5 wells. Fifteen physicochemical parameters and two fecal pollution indicators (Escherichia coli and fecal Coliforms) were monitored based on laboratory standard methods. Datas were analyzed, using the Student t’ test and XLSTAT 7.5.2 statistical software. From results obtained, water quality was related to water source and sampling period as well (p 0.0001). 30% of drillings provided water with nitrates concentration over the World Health Organization (WHO) guideline value. High turbidity was also observed for some drillings. Moreover, 90% of drillings showed water total hardness largely over the WHO threshold value. Water from drillings were exempt of fecal pollution, contrasting with the wells one which appeared uniformly polluted with concentrations exceeding sometimes 103 and 104 CFU/100 ml for E. coli and fecal Coliforms, respectively. Field investigations showed a preference of wells as drinking water source, and that appeared related to the lack of self-management of drillings and to cultural considerations. Overall, this study highlighted that a regular survey of water quality, management of protection zones around drinking water sources, sensitization on water resources self-management, hygiene and health issues, and providing appropriate household disinfection methods could help advancing to reach an effective safe drinking water access for rural populations in the country.
文摘Environmental pollution with petroleum and petrochemical products such as diesel and used oils has been recognized as one of the most serious current problem in the world, especially in developing countries. These petrochemical products devastate the soil, surface and underground waters and alter the microbial population at the polluted sites. Thus, the present work aims to optimize the biodegradation of diesel and two used oils (SAE 40 and SAE 50) by bacterial strains namely Acinetobacter S2 and Pseudomonas S7 using either nutrient factors (yeast extract, peptone or trace elements) or surfactants (tween 80 or Sodium Dodecyl Sulfate: SDS). The strains are incubated alone or together with the used oils or diesel supplemented or not with nutrient factors or surfactants for 14, 28, 42 and 56 days, respectively. For all the incubation period, the hydrocarbons degradation rates are determined by gravimetric assay. The results obtained show that nutrient factors increase significantly SAE 50 used oil biodegradation (p = 0.009). Similarly, tween 80 increases SAE 50 and SAE 40 used oils biodegradation but not diesel one. The results also show a significant difference between biodegradation rates at 14, 28, 42 and 56 days for all the hydro-carbons tested (p Acinetobacter S2 and Pseudomonas S7 increases the degradation over the one of the strains alone.
文摘Rice is one of the staple crops in Burkina Faso. However, the local production covers only 47% of the population demands. One of the main reasons of the poor productivity in Burkina Faso is iron toxicity which is related mainly to the activity of Iron Reducing Bacteria in the rice field’s ecosystems. In order to control the harmful effects of Iron Reducing Bacterial populations and to improve rice productivity, a pots experiment was conducted at the experimental site of the University Ouaga I Pr. Joseph KI-ZERBO. An iron toxic soil from Kou Valley (West of Burkina Faso) and two rice varieties, BOUAKE-189 and ROK-5, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were drained for 14 days (D2) and amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complexes). Control pots without drainage and fertilization (D0/NF) were prepared similarly. The kinetics of Iron Reducing Bacterial populations and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using a spectrometric method. Data obtained were analyzed in relation to drainage and fertilization mode, rice growth stage and rice yield using the Student’s t-test and XLSTAT 2014 statistical software. The experiment showed that the combined application of subsurface drainage and NPK + Urea + Ca + Mg + Zn fertilization, reduced significantly the number of IRB in the soil near rice roots for both rice varieties (p = 0.050 and p = 0.020) increased the leaf tissue tolerance to excess amounts of Fe, and rice yield.
文摘Iron toxicity is a major stress to rice caused by a high concentration of reduced iron, in the soil in many lowlands worldwide. To reduce iron toxicity in the West African lowlands, an investigation was performed at the site of the University of Ouagadougou, in pots containing an iron toxic soil from the Kou Valley (West of Burkina Faso). The experiment objective was to study the effect of mineral fertilizer on Iron Reducing Bacteria (IRB) dynamics and activity during rice cultivation, iron accumulation in rice plant and rice biomass yield under iron toxicity conditions. BOUAKE-189 and ROK-5 rice varieties, sensitive and tolerant to iron toxicity, respectively, were used for the experiment. The pots were amended with chemical fertilizers (NPK + Urea and NPK + Urea + Ca + Mg + Zn complex). Control pots without fertilization were prepared similarly. The kinetics of IRB and ferrous iron content in soil near rice roots were monitored throughout the cultural cycle using MPN and colorimetric methods, respectively. The total iron content was evaluated in rice plant using spectrometric method. Data obtained were analyzed in relation to fertilization mode, rice growth stage and rice yield using the student’s t-test and XLSTAT 2014 statistical software. The experiment revealed that NPK + Urea and NPK + Urea + Ca + Mg + Zn fertilization, decreased significantly (p < 0.0001) the number of IRB in the soil for BOUAKE-189 rice varieties. In most pots, highest IRB densities and ferrous iron content in soil were recorded from rice tillering and flowering to maturity stages, indicating that rice plants promoted microbial processes and iron reduction in soil. From the study, the NPK + Urea amendment decreased significantly ferrous iron content (p < 0.0001) in soil near BOUAKE-189 and ROK-5 rice varieties roots relatively to control pots. However, NPK + Urea + Ca + Zn + Mg amendment increased significantly ferrous iron content (p < 0.0001) in the soil near roots, Fe accumulation in plant biomass and rice yield for the two rice varieties.
基金supported by Tsinghua University Spring Breeze Fund(2021Z99CFY031)National Natural Science Foundation of China(32150024 and 92057209)supported by the Fundamental Research Funds for the Central Public Welfare Research Institutes(ZZ16-YQ-046 and ZZ16-ND10-13,China)。
文摘Emerging evidence has demonstrated the vital role of metabolism in various diseases or disorders.Metabolomics provides a comprehensive understanding of metabolism in biological systems.With advanced analytical techniques,metabolomics exhibits unprecedented significant value in basic drug research,including understanding disease mechanisms,identifying drug targets,and elucidating the mode of action of drugs.More importantly,metabolomics greatly accelerates the drug development process by predicting pharmacokinetics,pharmacodynamics,and drug response.In addition,metabolomics facilitates the exploration of drug repurposing and drug-drug interactions,as well as the development of personalized treatment strategies.Here,we briefly review the recent advances in technologies in metabolomics and update our knowledge of the applications of metabolomics in drug research and development.
基金ISP-SUEDE/RA-BIOTECH,PACER-UEMOA/RA-BIO-TECH,National Office of Water and Sanitation(ONEA)and CNRST/IRSS,for financial and technical supports
文摘Urban truck farming in developing countries appears of great importance to overcome unemployment and poverty. However, the quality of wastewater used for such activity could expose populations to waterborne diseases. The microbial quality of wastewaters used for truck farming in Ouagadougou city, was examined for the presence of bacterial and parasitological fecal indicators during the dry-hot season (May) and the wet season (July) in 2012. The wastewaters of three water reservoirs and two canals intensively used for truck farming were analyzed throughout the study. These indicators were also monitored in waste stabilization ponds during wastewater treatment in 3 plants of the city. For all the selected sampling sites, the concentrations of microbial indicators in water were significantly higher in the dry-hot season compared to the wet one (p - 53,800 CFU/100ml for Escherichia coli, 8200 - 108,400 CFU/100ml for fecal coliforms, 650 - 45,000 CFU/100ml) for fecal streptococcus, and 0 - 2.4 eggs/l for helminthes during the study periods. For wastewater under treatment in waste stabilization ponds, significant microbial concentration drops (p 0.0001) in the range of 82% - 100%, 78% - 98%, 60% - 100% and 82% - 88%, respectively were recorded between the anaerobic and the maturation ponds. The later results highlighted that improving the refining performances of the waste stabilization ponds technology could help decreasing health risks related to wastewater reuse in urban agriculture for a sustainable development of cities in developing countries.
