Background: Due to worldwide increases in the prevalence of antibiotic-resistant bacteria, it is necessary to develop an active drug delivery system that can enable therapeutics to reach their molecular targets. Maint...Background: Due to worldwide increases in the prevalence of antibiotic-resistant bacteria, it is necessary to develop an active drug delivery system that can enable therapeutics to reach their molecular targets. Maintaining the concentration of any drug in the blood at a certain level for a long time is critical in the practice of drug therapy. With the increased frequency of drug use, the blood concentration of drugs exceeds the therapeutic level, leading to toxicity or ineffectiveness. To solve these problems, in recent years, much attention has been given to developing micro/nano preparations by encapsulating biologically active compounds on polymeric carriers. Therefore, we aimed to extract pectin from sea buckthorn peel, prepare microcapsules containing antibiotics, and determine their physical and chemical properties. Methods: Wastes were separated from sea buckthorn under “Medical raw materials Dry fruit of Hippophae rhamnoides MNS 5225:2002”. Pectin was isolated from sea buckthorn waste according to the “method for determination of pectins MNS3080:1981” standard. The degree of esterification was determined according to ISO 7623:2016. Antibiotic encapsulation with coacervates and water-based emulsions was performed. Antibiotic sensitivity was determined by microdilution according to the Clinical Laboratory Standard Institute (МТ100-S27) method. The results were determined between standard strains of Staphylococcus aureus ATCC 29213 and MRSA ATCC 2758 at different dilution concentrations. Result: Pectin is a brown powder with a sour taste and no odor. There was 71.4% esterification of pectin, 8.9% yield, 1.3% free carboxyl group, 3.2% methylated carboxyl group, 4.5% total carboxyl group, 3.5% ash, and 0.1% nitrogen. A study of the antibacterial activity of pectin containing doxycycline hyclate found that the inhibition of bacterial growth was 0.8 times less than that of pure pectin. It was 1 time less than that of doxycycline alone, and 33 times smaller than that of wontaxime when compared to pure pectin. Pectin containing doxycycline hyclate inhibited MRSA growth at a concentration 6 times lower than pure pectin. This was 2 times lower than doxycycline alone, and 8 times lower than wontaxime. Conclusion: Pectin yields 1.3 after 60 minutes of separation at a sediment concentration ratio of 1:1.15 and pH = 2. Pectin itself is antibacterial against MRSA.展开更多
Aloin is the main medicinal component extracted from Aloe vera.It is a natural anthraquinone compound,with anticancer,anti-inflammatory and antibacterial and other biological functions.This paper reviews the pharmacol...Aloin is the main medicinal component extracted from Aloe vera.It is a natural anthraquinone compound,with anticancer,anti-inflammatory and antibacterial and other biological functions.This paper reviews the pharmacological action and related mechanisms of aloin,in order to provide a theoretical basis for the development and utilization of aloin.展开更多
Onion(Allium cepa L.)is a common biennial herb,and contains allicin compounds which can kill harmful microorganism.The antibacterial effects of raw and mature onion juice of purple,yellow and white-skinned onions at d...Onion(Allium cepa L.)is a common biennial herb,and contains allicin compounds which can kill harmful microorganism.The antibacterial effects of raw and mature onion juice of purple,yellow and white-skinned onions at different concentrations on Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were studied.There were differences among the antibacterial effects of raw and mature onion juice of purple,yellow and white-skinned onions at different concentrations.What was more,the antibacterial effects of raw onion juice were better than those of the mature one.The antibacterial effects of high concentration onion juice were better than those of the low one.The content of the total flavonoids in raw purple onion was higher than that in mature onion,and reached extremely significant levels in 50%,75%and 100%,respectively.Through comparison,it was found that onion juice of purple-skinned had the best suppression effects on S.aureus(gram-positive bacterium)and E.coli(gram-negative bacterium),and gram-positive bacterium had better suppression effects than gram-negative bacterium.It wound provide the basis about bioactive function and antibacterial drugs.展开更多
[Objectives]This study was conducted to investigate the antibacterial effect of the extract from Hedyotis hedyotidea(DC)Merr.[Methods]Through in-vitro antibacterial tests,the antibacterial effects of H.hedyotidea etha...[Objectives]This study was conducted to investigate the antibacterial effect of the extract from Hedyotis hedyotidea(DC)Merr.[Methods]Through in-vitro antibacterial tests,the antibacterial effects of H.hedyotidea ethanol extract on Escherichia coli,Staphylococcus aureus and Bacillus subtilis were analyzed.[Results]The extract had a low-susceptibility inhibitory effect to the three kinds of bacteria,and the minimal inhibitory concentrations(MICs)corresponding to S.aureus,E.coli and B.subtilis were 200,175 and 150 mg/ml,respectively.The minimal bactericidal concentrations(MBCs)corresponding to E.coli and S.aureus were both 500 mg/ml.[Conclusions]This study provides theoretical support for the wide application of H.hedyotidea.展开更多
Objective:To evaluate the antibacterial effect of aqueous and ethanolic moringa leaf extracts (Moringa oleifera) on the growth of gram-positive and negative bacteria.Methods:Paper disks were soaked with 100,200,300 an...Objective:To evaluate the antibacterial effect of aqueous and ethanolic moringa leaf extracts (Moringa oleifera) on the growth of gram-positive and negative bacteria.Methods:Paper disks were soaked with 100,200,300 and 400μL of extract at 20 g/180mL and 10 g/190 mL.All extracts were tested against Escherichia coli(ATCC25922),Staphylococcus aureus(ATCC25923),Vibrio parahaemolyticus,Enterococcus faecalis(ATCC29212),Pseudomonas aeruginosa(ATCC27853), Salmonella enteritidis(IH) and Aeromonas caviae.The susceptibility tests were performed using the modified disk diffusion method.Results:The strains E.coli,P.aeruginosa and S.enteritidis (IH) were resistant to all treatments.In general,disks with 400μL extract were the most efficient against S.aureus,V.parahaemolyticus,E.faecalis and A.caviae.Conclusions:The study indicates a promising potential for aqueous and ethanolic Moringa leaf extracts as alternative treatment of infections caused by the tested strains.展开更多
Objective:To evaluate the antibacterial properties ot Allium sativum(garlic) cloves and Zingiber officinale(ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection.Methods:The clo...Objective:To evaluate the antibacterial properties ot Allium sativum(garlic) cloves and Zingiber officinale(ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection.Methods:The cloves of garlic and rhizomes of ginger were extracted with 95%(v/v) ethanol.The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens.Results:Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates.All the bacterial isolates were susceptible to crude extracts of both plants extracts.Except Enterobacter sp.and Klebsiella sp.,all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger.The highest inhibition zone was observed with garlic(19.4S mm) against Pseudomonas aeruginosa(P.aeruginosa).The minimal inhibitory concentration was as low as 67.00 μg/mL against P.aeruginosa.Conclusions:Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.展开更多
AIM:To investigate the antibacterial effects of a crude extract of maggots against Escherichia coli(E.coli) and the underlying mechanisms,and to separate and purifythe crude extract of maggots to assess the antibacter...AIM:To investigate the antibacterial effects of a crude extract of maggots against Escherichia coli(E.coli) and the underlying mechanisms,and to separate and purifythe crude extract of maggots to assess the antibacterial effects of the active ingredients in the crude extract.METHODS:Different concentrations of the crude extract of maggots were incubated with E.coli(O157:H7) and cultured.The optical density(OD) was measured at different time points to plot the OD-T curve.The effects of different concentrations of the crude extract on bacterial membrane permeability were determined by fluorescence probe technique.The effects of different concentrations of the crude extract on plasmid DNA replication were determined by agarose gel electrophoresis.DEAE-Sepharose ion exchange chromatography and Sephacryls-200 HR gel filtration chromatography were used to separate and purify the crude extract of maggots.The molecular weight of proteins in the purified crude extract was determined by SDS-PAGD electrophoresis,and its antibacterial effects were determined by turbidimetric method.RESULTS:The antibacterial effects of the crude extract of maggots at concentrations > 0.5 mg/m L were significant.The antibacterial effects of the crude extract at concentrations of 1.0,1.5 and 2.0 mg/m L did not differ significantly.Fluorescence probe analysis showed that the rate of membrane permeability change was 1223.1% in bacteria incubated with 2 mg/m L of the crude extract,and 1300.0% in those incubated with 80 mg/m L of the crude extract.Plasmid DNA was undetectable in E.coli incubated with 2 and 80 mg/m L of the crude extract.A low molecular weight protein band(about 15 k Da) was detected in the crude extract of maggots and eluent,but not in eluant,from DEAE-Sepharose ion exchange chromatography.The antibacterial effects of the crude extract of maggots and eluent were superior to those of eluant,with the antibacterial effects of eluents being better than those of the crude extract of maggots.Of 24 tubes offiltrates,the antibacterial effects of filtrates in tubes 4,5 and 11 were significantly higher than those of the control.The molecular weight of the protein in filtrates in tubes 4,5 and 11 was about 15 k Da.CONCLUSION:The crude extract of maggots exhibits obvious,dose-dependent antibacterial effects.The crude extract exerts antibacterial effects by changing the bacterial membrane permeability and inhibiting plasmid DNA replication.The prote in that has antibacterial effects in the crude extract of maggots has a molecular weight of about 15 k Da.展开更多
Antibacterial effect of cinnamon oil combined with thyme or clove oil was studied in this paper.Agar dilution method was used to determine the minimum inhibitory concentrations(MICs) of the essential oils(EOs) of cinn...Antibacterial effect of cinnamon oil combined with thyme or clove oil was studied in this paper.Agar dilution method was used to determine the minimum inhibitory concentrations(MICs) of the essential oils(EOs) of cinnamon,thyme,and clove oil against three Gram-positive bacteria(Bacillus subtilis,Bacillus cereus,and Staphylococcus aureus),and two Gram-negative bacteria(Escherichia coli and Salmonella typhimurium).The results showed that cinnamon was a promising antibacterial substance with MIC ranged from 0.1 to 0.4 μL mL-1 for the five bacterial species.Agar dilution checkerboard method was used to test the combined antibacterial effect of cinnamon oil with thyme or clove oil.Combination of cinnamon and thyme oil showed an additive effect against all selected bacteria,and combination of cinnamon and clove oil displayed an additive effect against B.subtilis,B.cereus,S.aureus,and an indifferent effect against E.coli and S.typhimurium.Furthermore,gas chromatography-mass spectrometry(GC-MS) measurement was used to analyze the components of the EOs,and the main components of cinnamon,thyme,and clove were cinnamaldehyde,thymol,carvacrol and p-cymene,and eugenol,respectively.展开更多
Objective: To study and analyze the antibacterial effects of different extracts from Radix Isatis. Methods: Staphylococcus aureus was used as the studied object in the experiment. Antibacterial effects of extracts fro...Objective: To study and analyze the antibacterial effects of different extracts from Radix Isatis. Methods: Staphylococcus aureus was used as the studied object in the experiment. Antibacterial effects of extracts from Radix Isatis were observed by thermocalrimetry on Staphylococcus aureus, together with common pharmacological experiments. Results: The total extract, ethyl acetate （EtOAc） extract, n-butylalcohol （nBuOH） extract, chloroform （CHCl3） extract and petroleum （P.E.） extract had antiviral effects to some extent while the residue after extracting had no antibacterial activity. The potency of antiviral activity among them was as follows: nBuOH extract > EtOAc extract > CHCl3 extract> total extract >P.E. extract. Conclusion: The antibacteriall effects of Radix Isatis were not limited to any active portion, showing that Radix Isatis exerts its antibacterial effects by cooperation of different active fractions in varied ways.展开更多
In order to understand in vitro antibacterial effect of antibiotics and EM on Aeromonas hydrophila,14 isolates of A. hydrophila were isolated from diseased fish and aquaculture in the study. PCR amplification results ...In order to understand in vitro antibacterial effect of antibiotics and EM on Aeromonas hydrophila,14 isolates of A. hydrophila were isolated from diseased fish and aquaculture in the study. PCR amplification results of aerolysin gene( Aero gene) of isolates indicated that 7 out of 14 isolates were pathogenic A.hydrophila. In vitro antibacterial test indicated that 14 isolates were resistance to penicillin G,ampicillin,cephradine,cefazolin,tetracycline,terimethoprim,lincomycin and cephalexin,but showed high sensitivity to cefotaxime and furazolidone. In vitro antibacterial effect of EM on 14 isolates of A. hydrophila was positively correlated with concentration,and EM with the concentration greater than 60% had antibacterial effect on 14 isolates.展开更多
[Objectives]To explore the antibacterial effects of essential oils from pomegranate on two kinds of postharvest pathogenic fungi,and to provide reference for the exploration of new plant-derived preservatives for pome...[Objectives]To explore the antibacterial effects of essential oils from pomegranate on two kinds of postharvest pathogenic fungi,and to provide reference for the exploration of new plant-derived preservatives for pomegranate.[Methods]The inhibitory effects of 15 kinds of plant essential oils on 2 kinds of pomegranate postharvest pathogenic fungi were studied.[Results]Tea tree oil and eucalyptus oil have good inhibitory effects on the mycelium growth of Coniella granati and Botrytis cinerea,and the fumigation treatment of pomegranate can inhibit the rot of fruit during storage to a certain extent.[Conclusions]Tea tree oil and eucalyptus oil can effectively inhibit the mycelium growth of two kinds of pathogenic fungi,and can better control the rot of pomegranate during storage.It is necessary to further study the fresh-keeping effect and antibacterial mechanism of plant essential oils on pomegranate.展开更多
Introduction: Intestinal bacteria are exposed many external influences, including drugs, causing the emergence of strains resistant to the effects of antibiotics. Consequently, the discovery of new antibiotics that af...Introduction: Intestinal bacteria are exposed many external influences, including drugs, causing the emergence of strains resistant to the effects of antibiotics. Consequently, the discovery of new antibiotics that affect resistant strains is required. Marine algae offer a source of renewable natural compounds with antimicrobial effects. Therefore, the aim of this study was to detect some of these compounds and examine their impact on enteric bacteria. Methodology: Escherichia coli, Salmonella typhi, Shigella dysenteriae, Klebsiella pneumoniae, and Enterobacter aerogenes were tested with extracts of Turbinaria triquetra and Halimeda opuntia extracted with methanol, ethanol, petroleum ether, or dimethyl formamide solvents. We measured bacterial growth inhibition, the minimal inhibitory concentrations (MICs), and potassium leakage, and analyzed the bacterial cells with scanning electron microscopy and energy-dispersive X-ray spectroscopy. Results: The T. triquetra extract produced with methanol strongly affected the bacteria tested. When the results for T. triquetra and H. opuntia were compared with those of omacillin, the T. triquetra and H. opuntia extracts in most solvents were more effective than the antibiotic. Differences in the bacterial growth inhibition and MICs depended on the type of alga and the solvent used. At the end of the incubation period, potassium leakage had increased by 62.98% for E. coli, 61.24% for S. typhi, 61.32% for S. dysenteriae, 64.02% for K. pneumoniae, and 63.10% for E. aerogenes when treated T. triquetra. Conclusion: Turbinaria triquetra extracted with methanol strongly affected the growth of the bacteria tested. Therefore, it is a potential source of natural antibacterial compounds.展开更多
Recently, there is a need of alternatives to antibiotics due to increasing antibiotic-resistant microorganism. Promising classes of bioactive polymers are 6-deoxy-6-amino cellulose derivatives. The purpose of the stud...Recently, there is a need of alternatives to antibiotics due to increasing antibiotic-resistant microorganism. Promising classes of bioactive polymers are 6-deoxy-6-amino cellulose derivatives. The purpose of the study was the assessment of the biocompatibility of 6-deoxy-6-aminoethyleneamino cellulose (AEAC) with different degree of substitution (DS). HaCaT keratinocyte cell viability was analyzed by measuring the cellular ATP content. The antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae was examined by microplate laser nephelometry. Thus, the ratio of half-maximal lethal concentration (LC50) and half-maximal inhibitory concentration (IC50) was calculated and described as biocompatibility index. The study revealed that biocompatibility of AEAC depends on the DS. AEAC of low DS (0.3) showed the best biocompatibility.展开更多
To obtain the safety of drinking water, an antibacterial material was prepared by loading silver (Ag) onto fibrous iminodiacetate (IDA) adsorbent, which was synthesized by radiation-induced graft polymerization of gly...To obtain the safety of drinking water, an antibacterial material was prepared by loading silver (Ag) onto fibrous iminodiacetate (IDA) adsorbent, which was synthesized by radiation-induced graft polymerization of glycidyl methacrylate and subsequent chemical modification of the produced epoxy group to an IDA group (IDA-Ag). A total amount of loaded Ag on the IDA-Ag fabric was 0.4 mmol-Ag/g-fabric. From an observation of the IDA-Ag fabric cross section by a scanning electron microscope energy dispersive X-ray spectrometer, Ag was distributed to IDA layer uniformly. As a result of evaluating antibacterial effects by the column mode water flow test with stream water, the effective Ag concentration was monitored 0.05 ppm at irrespective flow rate which was functioned to the antibacterial performance. The antibacterial effects for general bacteria were indicated until BV (BV: steam water volume/IDA-Ag fabric volume) 6000, and for colitis germ legions were completely disinfected until BV 6000.展开更多
The antibacterial effect of carrying silver B2O3-SiO2-Na2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimental ...The antibacterial effect of carrying silver B2O3-SiO2-Na2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimental results of five kinds of antibacterial test methods are almost identical and can verify that carrying silver B2O3-SiO2-Na2O glass material exerts an excellent antibacterial performance. Antibacterial ring and nephelometery are simple, quick, but the precision is restrictive. MIC value, thin film attachment method and microcalorimetry can quantitatively compare the antibacterial effects of the antibacterial glass material.Compared with the traditional microbe test methods, the microcalorimetry can analyze the inhibiting effect of the cell’s growth and metabolism on the antibacterial glass material by monitoring the thermal effect continuously and automatically.展开更多
Background: Artemisia afra is an indigenous plant used in Africa. It is used in traditional medicine to treat a variety of diseases caused by bacterial infections. As a result, developing innovative therapeutic method...Background: Artemisia afra is an indigenous plant used in Africa. It is used in traditional medicine to treat a variety of diseases caused by bacterial infections. As a result, developing innovative therapeutic methods using natural ingredients to combat pathogenic germs is critical. Methodology: Artemisia afra leaves were extracted using maceration extraction utilizing three solvents (petroleum ether, ethanol, and dichloromethane). Fresh leaves were extracted using hydrodistillation. The agar well diffusion method was used to test the crude extract and essential oil leaves of Artemisia afra against different human pathogenic bacteria strains (E. coli, S. aureus, E. faecalis, and K. pneumonia) at different concentrations in the presence of a positive (ciprofloxacin 5.0 μg) and negative (DMSO) control. Results: Artemisia afra revealed the presence of alkaloids, flavonoids, tannins, saponins, anthraquinones, terpenoids, coumarins, phenolic quinones, cardiac glycosides, and steroids. It showed that the highest antibacterial activity given by the ethanol extract had highly inhibition zones against gram-positive and gram-negative bacteria. The essential oil extract was effective against all tested bacteria. Conclusion: Plant crude extracts and essential oils may have antibacterial properties due to the synergistic activity of two or more active secondary metabolites.展开更多
The Manganese doped zinc sulfide nanoparticles of the cubic zinc blende structure with the average crystallite size of about 3.56 nm were synthesized using a coprecipitation method using Thioglycolic Acid as an extern...The Manganese doped zinc sulfide nanoparticles of the cubic zinc blende structure with the average crystallite size of about 3.56 nm were synthesized using a coprecipitation method using Thioglycolic Acid as an external capping agent for surface modification. The ZnS:Mn<sup>2+</sup> nanoparticles of diameter 3.56 nm were manufactured through using inexpensive precursors in an efficient and eco-friendly way. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy are used to examine the structure, morphology and chemical composition of the nanoparticles. The antimicrobial activity of (ZnS:Mn<sup>2+</sup>) nanocrystals was investigated by measuring the diameter of inhibition zone using well diffusion mechanism versus two various bacterial strains. The technique of microorganism inactivation was considered as sorts-dependent. Bacillus subtilis showed the largest antibacterial sensitivity (35 mm) to ZnS: Mn<sup>2+</sup> nanoparticles at a concentration (50 mM) whereas Escherichia coli offered maximum zone of inhibition (20 mm) at the same concentration. In this study, the results indicated that ZnS:Mn<sup>2+</sup> nanoparticles were found to have significant antibacterial activity against Gram-negative (E. coli) and Gram-positive (Bacillus subtilis) bacteria.展开更多
To observe the germistatic and germicidal effects of origanum volatile oil (OVI) on the dysentery bacteria, the abdominal cavity of mice was infected with Shigella sonne (Sh. sonnei) and Shigella flexneri (Sh. flexner...To observe the germistatic and germicidal effects of origanum volatile oil (OVI) on the dysentery bacteria, the abdominal cavity of mice was infected with Shigella sonne (Sh. sonnei) and Shigella flexneri (Sh. flexneri) F 2a. After OVI was given to the mice via gastric lavage, the effects of OVI on the infected mice were observed. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) for dysentery bacteria were determined in vitro. The results showed that origanum volatile oil showed obvious protective effect on mice infected with Sh. sonnei and Sh. flexneri F 2a. and it had germistatic and germicidal effects on dysentry bacteria. We are led to conclude that origanum volatile oil is an effective medicine against the infection of dysentery bacteria.展开更多
文摘Background: Due to worldwide increases in the prevalence of antibiotic-resistant bacteria, it is necessary to develop an active drug delivery system that can enable therapeutics to reach their molecular targets. Maintaining the concentration of any drug in the blood at a certain level for a long time is critical in the practice of drug therapy. With the increased frequency of drug use, the blood concentration of drugs exceeds the therapeutic level, leading to toxicity or ineffectiveness. To solve these problems, in recent years, much attention has been given to developing micro/nano preparations by encapsulating biologically active compounds on polymeric carriers. Therefore, we aimed to extract pectin from sea buckthorn peel, prepare microcapsules containing antibiotics, and determine their physical and chemical properties. Methods: Wastes were separated from sea buckthorn under “Medical raw materials Dry fruit of Hippophae rhamnoides MNS 5225:2002”. Pectin was isolated from sea buckthorn waste according to the “method for determination of pectins MNS3080:1981” standard. The degree of esterification was determined according to ISO 7623:2016. Antibiotic encapsulation with coacervates and water-based emulsions was performed. Antibiotic sensitivity was determined by microdilution according to the Clinical Laboratory Standard Institute (МТ100-S27) method. The results were determined between standard strains of Staphylococcus aureus ATCC 29213 and MRSA ATCC 2758 at different dilution concentrations. Result: Pectin is a brown powder with a sour taste and no odor. There was 71.4% esterification of pectin, 8.9% yield, 1.3% free carboxyl group, 3.2% methylated carboxyl group, 4.5% total carboxyl group, 3.5% ash, and 0.1% nitrogen. A study of the antibacterial activity of pectin containing doxycycline hyclate found that the inhibition of bacterial growth was 0.8 times less than that of pure pectin. It was 1 time less than that of doxycycline alone, and 33 times smaller than that of wontaxime when compared to pure pectin. Pectin containing doxycycline hyclate inhibited MRSA growth at a concentration 6 times lower than pure pectin. This was 2 times lower than doxycycline alone, and 8 times lower than wontaxime. Conclusion: Pectin yields 1.3 after 60 minutes of separation at a sediment concentration ratio of 1:1.15 and pH = 2. Pectin itself is antibacterial against MRSA.
基金Supported by Central Government Supports Local College Reform and Development Fund Talent Training Projects(2020GSP16)Heilongjiang Provincial Key Research and Development Plan Guidance Project(GZ20220039)Postgraduate Innovative Research Project of Heilongjiang Bayi Agricultural University(YJSCX2022-Y55).
文摘Aloin is the main medicinal component extracted from Aloe vera.It is a natural anthraquinone compound,with anticancer,anti-inflammatory and antibacterial and other biological functions.This paper reviews the pharmacological action and related mechanisms of aloin,in order to provide a theoretical basis for the development and utilization of aloin.
基金Supported by the Scientific Research Projects of Basic Scientific Research Business Expenses of Undergraduate Universities in Heilongjiang Province(135309363)Fundamental Research Business Expenses of Heilongjiang Provincial Universities(Specialized Subjects of Plant Food Processing Technology)(YSTSXK201889)+2 种基金Heilongjiang General Undergraduate Universities Young Innovative Talents Training Plan(UNPYSCT-2018101)Natural Science Foundation of Heilongjiang Province(LH2019C067)Science and Technology Plan Project of Qiqihar City(NYGG-201915)。
文摘Onion(Allium cepa L.)is a common biennial herb,and contains allicin compounds which can kill harmful microorganism.The antibacterial effects of raw and mature onion juice of purple,yellow and white-skinned onions at different concentrations on Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were studied.There were differences among the antibacterial effects of raw and mature onion juice of purple,yellow and white-skinned onions at different concentrations.What was more,the antibacterial effects of raw onion juice were better than those of the mature one.The antibacterial effects of high concentration onion juice were better than those of the low one.The content of the total flavonoids in raw purple onion was higher than that in mature onion,and reached extremely significant levels in 50%,75%and 100%,respectively.Through comparison,it was found that onion juice of purple-skinned had the best suppression effects on S.aureus(gram-positive bacterium)and E.coli(gram-negative bacterium),and gram-positive bacterium had better suppression effects than gram-negative bacterium.It wound provide the basis about bioactive function and antibacterial drugs.
文摘[Objectives]This study was conducted to investigate the antibacterial effect of the extract from Hedyotis hedyotidea(DC)Merr.[Methods]Through in-vitro antibacterial tests,the antibacterial effects of H.hedyotidea ethanol extract on Escherichia coli,Staphylococcus aureus and Bacillus subtilis were analyzed.[Results]The extract had a low-susceptibility inhibitory effect to the three kinds of bacteria,and the minimal inhibitory concentrations(MICs)corresponding to S.aureus,E.coli and B.subtilis were 200,175 and 150 mg/ml,respectively.The minimal bactericidal concentrations(MBCs)corresponding to E.coli and S.aureus were both 500 mg/ml.[Conclusions]This study provides theoretical support for the wide application of H.hedyotidea.
文摘Objective:To evaluate the antibacterial effect of aqueous and ethanolic moringa leaf extracts (Moringa oleifera) on the growth of gram-positive and negative bacteria.Methods:Paper disks were soaked with 100,200,300 and 400μL of extract at 20 g/180mL and 10 g/190 mL.All extracts were tested against Escherichia coli(ATCC25922),Staphylococcus aureus(ATCC25923),Vibrio parahaemolyticus,Enterococcus faecalis(ATCC29212),Pseudomonas aeruginosa(ATCC27853), Salmonella enteritidis(IH) and Aeromonas caviae.The susceptibility tests were performed using the modified disk diffusion method.Results:The strains E.coli,P.aeruginosa and S.enteritidis (IH) were resistant to all treatments.In general,disks with 400μL extract were the most efficient against S.aureus,V.parahaemolyticus,E.faecalis and A.caviae.Conclusions:The study indicates a promising potential for aqueous and ethanolic Moringa leaf extracts as alternative treatment of infections caused by the tested strains.
基金financrally supported by K.S.Rangasamy College of Arts and Science.Kuchipalayam,Tiruchengodr.Tamil Nadu,India(grant No.KSRCAS/PG/MB/0010 dt.10.11.2010)
文摘Objective:To evaluate the antibacterial properties ot Allium sativum(garlic) cloves and Zingiber officinale(ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection.Methods:The cloves of garlic and rhizomes of ginger were extracted with 95%(v/v) ethanol.The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens.Results:Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates.All the bacterial isolates were susceptible to crude extracts of both plants extracts.Except Enterobacter sp.and Klebsiella sp.,all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger.The highest inhibition zone was observed with garlic(19.4S mm) against Pseudomonas aeruginosa(P.aeruginosa).The minimal inhibitory concentration was as low as 67.00 μg/mL against P.aeruginosa.Conclusions:Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.
基金Supported by National Natural Science Foundation of China,No.81270052
文摘AIM:To investigate the antibacterial effects of a crude extract of maggots against Escherichia coli(E.coli) and the underlying mechanisms,and to separate and purifythe crude extract of maggots to assess the antibacterial effects of the active ingredients in the crude extract.METHODS:Different concentrations of the crude extract of maggots were incubated with E.coli(O157:H7) and cultured.The optical density(OD) was measured at different time points to plot the OD-T curve.The effects of different concentrations of the crude extract on bacterial membrane permeability were determined by fluorescence probe technique.The effects of different concentrations of the crude extract on plasmid DNA replication were determined by agarose gel electrophoresis.DEAE-Sepharose ion exchange chromatography and Sephacryls-200 HR gel filtration chromatography were used to separate and purify the crude extract of maggots.The molecular weight of proteins in the purified crude extract was determined by SDS-PAGD electrophoresis,and its antibacterial effects were determined by turbidimetric method.RESULTS:The antibacterial effects of the crude extract of maggots at concentrations > 0.5 mg/m L were significant.The antibacterial effects of the crude extract at concentrations of 1.0,1.5 and 2.0 mg/m L did not differ significantly.Fluorescence probe analysis showed that the rate of membrane permeability change was 1223.1% in bacteria incubated with 2 mg/m L of the crude extract,and 1300.0% in those incubated with 80 mg/m L of the crude extract.Plasmid DNA was undetectable in E.coli incubated with 2 and 80 mg/m L of the crude extract.A low molecular weight protein band(about 15 k Da) was detected in the crude extract of maggots and eluent,but not in eluant,from DEAE-Sepharose ion exchange chromatography.The antibacterial effects of the crude extract of maggots and eluent were superior to those of eluant,with the antibacterial effects of eluents being better than those of the crude extract of maggots.Of 24 tubes offiltrates,the antibacterial effects of filtrates in tubes 4,5 and 11 were significantly higher than those of the control.The molecular weight of the protein in filtrates in tubes 4,5 and 11 was about 15 k Da.CONCLUSION:The crude extract of maggots exhibits obvious,dose-dependent antibacterial effects.The crude extract exerts antibacterial effects by changing the bacterial membrane permeability and inhibiting plasmid DNA replication.The prote in that has antibacterial effects in the crude extract of maggots has a molecular weight of about 15 k Da.
基金supported by the National High-Tech R&D Program of China (863 Program)(SQ2007AA10XK140105)the Zhejiang Province Key Scientific and Technological Project, China(2006C12051)the Zhejiang Provincial Center for Disease Control and Prevention (CDC) (Hangzhou,China)
文摘Antibacterial effect of cinnamon oil combined with thyme or clove oil was studied in this paper.Agar dilution method was used to determine the minimum inhibitory concentrations(MICs) of the essential oils(EOs) of cinnamon,thyme,and clove oil against three Gram-positive bacteria(Bacillus subtilis,Bacillus cereus,and Staphylococcus aureus),and two Gram-negative bacteria(Escherichia coli and Salmonella typhimurium).The results showed that cinnamon was a promising antibacterial substance with MIC ranged from 0.1 to 0.4 μL mL-1 for the five bacterial species.Agar dilution checkerboard method was used to test the combined antibacterial effect of cinnamon oil with thyme or clove oil.Combination of cinnamon and thyme oil showed an additive effect against all selected bacteria,and combination of cinnamon and clove oil displayed an additive effect against B.subtilis,B.cereus,S.aureus,and an indifferent effect against E.coli and S.typhimurium.Furthermore,gas chromatography-mass spectrometry(GC-MS) measurement was used to analyze the components of the EOs,and the main components of cinnamon,thyme,and clove were cinnamaldehyde,thymol,carvacrol and p-cymene,and eugenol,respectively.
基金Supported by Foundation of State Administration of Tradi-tional Chinese Medicine (No .04-05ZP70)
文摘Objective: To study and analyze the antibacterial effects of different extracts from Radix Isatis. Methods: Staphylococcus aureus was used as the studied object in the experiment. Antibacterial effects of extracts from Radix Isatis were observed by thermocalrimetry on Staphylococcus aureus, together with common pharmacological experiments. Results: The total extract, ethyl acetate （EtOAc） extract, n-butylalcohol （nBuOH） extract, chloroform （CHCl3） extract and petroleum （P.E.） extract had antiviral effects to some extent while the residue after extracting had no antibacterial activity. The potency of antiviral activity among them was as follows: nBuOH extract > EtOAc extract > CHCl3 extract> total extract >P.E. extract. Conclusion: The antibacteriall effects of Radix Isatis were not limited to any active portion, showing that Radix Isatis exerts its antibacterial effects by cooperation of different active fractions in varied ways.
基金Supported by Cooperation Project(09003699)Project of Jiangxi Department of Education(GJJ12237)Project of Jiangxi Department of Science and Technology(20122BBF60082)
文摘In order to understand in vitro antibacterial effect of antibiotics and EM on Aeromonas hydrophila,14 isolates of A. hydrophila were isolated from diseased fish and aquaculture in the study. PCR amplification results of aerolysin gene( Aero gene) of isolates indicated that 7 out of 14 isolates were pathogenic A.hydrophila. In vitro antibacterial test indicated that 14 isolates were resistance to penicillin G,ampicillin,cephradine,cefazolin,tetracycline,terimethoprim,lincomycin and cephalexin,but showed high sensitivity to cefotaxime and furazolidone. In vitro antibacterial effect of EM on 14 isolates of A. hydrophila was positively correlated with concentration,and EM with the concentration greater than 60% had antibacterial effect on 14 isolates.
基金Sichuan South Asia Crop Innovation Team Project of China Modern Agricultural Industry Technology SystemDoctoral Research Start-up Fund of Xichang University(2017BS003).
文摘[Objectives]To explore the antibacterial effects of essential oils from pomegranate on two kinds of postharvest pathogenic fungi,and to provide reference for the exploration of new plant-derived preservatives for pomegranate.[Methods]The inhibitory effects of 15 kinds of plant essential oils on 2 kinds of pomegranate postharvest pathogenic fungi were studied.[Results]Tea tree oil and eucalyptus oil have good inhibitory effects on the mycelium growth of Coniella granati and Botrytis cinerea,and the fumigation treatment of pomegranate can inhibit the rot of fruit during storage to a certain extent.[Conclusions]Tea tree oil and eucalyptus oil can effectively inhibit the mycelium growth of two kinds of pathogenic fungi,and can better control the rot of pomegranate during storage.It is necessary to further study the fresh-keeping effect and antibacterial mechanism of plant essential oils on pomegranate.
文摘Introduction: Intestinal bacteria are exposed many external influences, including drugs, causing the emergence of strains resistant to the effects of antibiotics. Consequently, the discovery of new antibiotics that affect resistant strains is required. Marine algae offer a source of renewable natural compounds with antimicrobial effects. Therefore, the aim of this study was to detect some of these compounds and examine their impact on enteric bacteria. Methodology: Escherichia coli, Salmonella typhi, Shigella dysenteriae, Klebsiella pneumoniae, and Enterobacter aerogenes were tested with extracts of Turbinaria triquetra and Halimeda opuntia extracted with methanol, ethanol, petroleum ether, or dimethyl formamide solvents. We measured bacterial growth inhibition, the minimal inhibitory concentrations (MICs), and potassium leakage, and analyzed the bacterial cells with scanning electron microscopy and energy-dispersive X-ray spectroscopy. Results: The T. triquetra extract produced with methanol strongly affected the bacteria tested. When the results for T. triquetra and H. opuntia were compared with those of omacillin, the T. triquetra and H. opuntia extracts in most solvents were more effective than the antibiotic. Differences in the bacterial growth inhibition and MICs depended on the type of alga and the solvent used. At the end of the incubation period, potassium leakage had increased by 62.98% for E. coli, 61.24% for S. typhi, 61.32% for S. dysenteriae, 64.02% for K. pneumoniae, and 63.10% for E. aerogenes when treated T. triquetra. Conclusion: Turbinaria triquetra extracted with methanol strongly affected the growth of the bacteria tested. Therefore, it is a potential source of natural antibacterial compounds.
文摘Recently, there is a need of alternatives to antibiotics due to increasing antibiotic-resistant microorganism. Promising classes of bioactive polymers are 6-deoxy-6-amino cellulose derivatives. The purpose of the study was the assessment of the biocompatibility of 6-deoxy-6-aminoethyleneamino cellulose (AEAC) with different degree of substitution (DS). HaCaT keratinocyte cell viability was analyzed by measuring the cellular ATP content. The antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae was examined by microplate laser nephelometry. Thus, the ratio of half-maximal lethal concentration (LC50) and half-maximal inhibitory concentration (IC50) was calculated and described as biocompatibility index. The study revealed that biocompatibility of AEAC depends on the DS. AEAC of low DS (0.3) showed the best biocompatibility.
文摘To obtain the safety of drinking water, an antibacterial material was prepared by loading silver (Ag) onto fibrous iminodiacetate (IDA) adsorbent, which was synthesized by radiation-induced graft polymerization of glycidyl methacrylate and subsequent chemical modification of the produced epoxy group to an IDA group (IDA-Ag). A total amount of loaded Ag on the IDA-Ag fabric was 0.4 mmol-Ag/g-fabric. From an observation of the IDA-Ag fabric cross section by a scanning electron microscope energy dispersive X-ray spectrometer, Ag was distributed to IDA layer uniformly. As a result of evaluating antibacterial effects by the column mode water flow test with stream water, the effective Ag concentration was monitored 0.05 ppm at irrespective flow rate which was functioned to the antibacterial performance. The antibacterial effects for general bacteria were indicated until BV (BV: steam water volume/IDA-Ag fabric volume) 6000, and for colitis germ legions were completely disinfected until BV 6000.
文摘The antibacterial effect of carrying silver B2O3-SiO2-Na2O glass material was studied by means of antibacterial ring, nephelometery,MIC value, thin film attachment and microcalorimetry, respectively. The experimental results of five kinds of antibacterial test methods are almost identical and can verify that carrying silver B2O3-SiO2-Na2O glass material exerts an excellent antibacterial performance. Antibacterial ring and nephelometery are simple, quick, but the precision is restrictive. MIC value, thin film attachment method and microcalorimetry can quantitatively compare the antibacterial effects of the antibacterial glass material.Compared with the traditional microbe test methods, the microcalorimetry can analyze the inhibiting effect of the cell’s growth and metabolism on the antibacterial glass material by monitoring the thermal effect continuously and automatically.
文摘Background: Artemisia afra is an indigenous plant used in Africa. It is used in traditional medicine to treat a variety of diseases caused by bacterial infections. As a result, developing innovative therapeutic methods using natural ingredients to combat pathogenic germs is critical. Methodology: Artemisia afra leaves were extracted using maceration extraction utilizing three solvents (petroleum ether, ethanol, and dichloromethane). Fresh leaves were extracted using hydrodistillation. The agar well diffusion method was used to test the crude extract and essential oil leaves of Artemisia afra against different human pathogenic bacteria strains (E. coli, S. aureus, E. faecalis, and K. pneumonia) at different concentrations in the presence of a positive (ciprofloxacin 5.0 μg) and negative (DMSO) control. Results: Artemisia afra revealed the presence of alkaloids, flavonoids, tannins, saponins, anthraquinones, terpenoids, coumarins, phenolic quinones, cardiac glycosides, and steroids. It showed that the highest antibacterial activity given by the ethanol extract had highly inhibition zones against gram-positive and gram-negative bacteria. The essential oil extract was effective against all tested bacteria. Conclusion: Plant crude extracts and essential oils may have antibacterial properties due to the synergistic activity of two or more active secondary metabolites.
文摘The Manganese doped zinc sulfide nanoparticles of the cubic zinc blende structure with the average crystallite size of about 3.56 nm were synthesized using a coprecipitation method using Thioglycolic Acid as an external capping agent for surface modification. The ZnS:Mn<sup>2+</sup> nanoparticles of diameter 3.56 nm were manufactured through using inexpensive precursors in an efficient and eco-friendly way. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy are used to examine the structure, morphology and chemical composition of the nanoparticles. The antimicrobial activity of (ZnS:Mn<sup>2+</sup>) nanocrystals was investigated by measuring the diameter of inhibition zone using well diffusion mechanism versus two various bacterial strains. The technique of microorganism inactivation was considered as sorts-dependent. Bacillus subtilis showed the largest antibacterial sensitivity (35 mm) to ZnS: Mn<sup>2+</sup> nanoparticles at a concentration (50 mM) whereas Escherichia coli offered maximum zone of inhibition (20 mm) at the same concentration. In this study, the results indicated that ZnS:Mn<sup>2+</sup> nanoparticles were found to have significant antibacterial activity against Gram-negative (E. coli) and Gram-positive (Bacillus subtilis) bacteria.
文摘To observe the germistatic and germicidal effects of origanum volatile oil (OVI) on the dysentery bacteria, the abdominal cavity of mice was infected with Shigella sonne (Sh. sonnei) and Shigella flexneri (Sh. flexneri) F 2a. After OVI was given to the mice via gastric lavage, the effects of OVI on the infected mice were observed. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) for dysentery bacteria were determined in vitro. The results showed that origanum volatile oil showed obvious protective effect on mice infected with Sh. sonnei and Sh. flexneri F 2a. and it had germistatic and germicidal effects on dysentry bacteria. We are led to conclude that origanum volatile oil is an effective medicine against the infection of dysentery bacteria.
