The effects of two chlorinated chiral stationary phases, namely, Lux Cellulose-2 and Lux i-Cellulose-5, flow-rate, percentage of co-solvent and chemical structures of the compounds on retention and resolution were stu...The effects of two chlorinated chiral stationary phases, namely, Lux Cellulose-2 and Lux i-Cellulose-5, flow-rate, percentage of co-solvent and chemical structures of the compounds on retention and resolution were studied within this article. In this work a backpressure of 150 bar, a temperature of 40 ℃ and 10% of methanol as co-solvent were chosen as operating conditions. The optimum flow-rate was 2 mL/min. The percentage of co-solvent was studied between 7.5% and 15%.We have observed that 15% of methanol gave the best results for most of the compounds. For all the derivatives, the Lux Cellulose-2 provided better resolutions going from 1.50 to 3.59 compared with Lux i-Cellulose-5.展开更多
Objective:To investigate the isolation of marine antibiotic-producing bacteria from the Persian Gulf,as an untapped source for searching new natural antibiotics.Methods:Initially water and sediment samples were collec...Objective:To investigate the isolation of marine antibiotic-producing bacteria from the Persian Gulf,as an untapped source for searching new natural antibiotics.Methods:Initially water and sediment samples were collected from 18 study sites in the some northern areas of Persian Gulf.All of the bacterial isolates using Marine Agar 2216 were inoculated into Marine broth and incubated on a rotary shaker at 28℃for 2-7 days.Bioactivily of their ethyl acetate extract was assessed at 100 mg/mL concentration in disc diffusion method against 6 gram-positive and 5 gram-negative bacteria.Synthetic antibiotics were used as control.Results:Altogether,46 bacterial colonies were isolated.Only one isolate from a marine sediment sample collected at a depth of 10 m,identified as Pseudomonas aeruginosa PG-01,was exhibited the capability of antibiotic production.The obtained raw extract from intended bacterium was effective against all tested gram positive bacteria while gram negative bacteria were resistance.Methicillin resisitant Stapuylococcus aureus(MRSA),Streptococcus pyogenes(S.pyogenes).Staphylococcus epidermidis (S.epidermidis) and Bacillus cereus(B.cereus) were the most sensitive strains.All of tested pathogens were multidrug resistant.The antibacterial compound from this bacterium was active even at 120℃.The optimized temperature and time for antibacterial metabolite production were 37℃and 72 hrs,respectively.Conclusions:Considering the antibacterial effect of Pseudomonas aeruginosa PG-01 especially against MRSA,it can be regarded the intended bacterium as a valuable strain and can give hope for treatment of diseases caused by multidrug resistant bacteria.展开更多
Objective: To study the antibacterial and antifungal activities of methanolic extract of roots of Carissa opaca and its fractions in hexane, chloroform, ethyl acetate, n-butanol and water, and the isolated compounds.M...Objective: To study the antibacterial and antifungal activities of methanolic extract of roots of Carissa opaca and its fractions in hexane, chloroform, ethyl acetate, n-butanol and water, and the isolated compounds.Methods: The zones of inhibition of the samples against test microorganisms were determined by agar well diffusion method. Minimum inhibitory concentrations of the samples were determined by agar well dilution method. Test microorganisms included four standard bacteria [Bacillus subtilis ATCC 6633(B. subtilis), Escherichia coli ATCC 8739(E. coli), Pseudomonas aeruginosa ATCC 9027(P. aeruginosa), and Staphylococcus aureus ATCC 6538], two standard fungi [Candida albicans ATCC 10231(C. albicans)] and Aspergillus niger, and six clinical isolates(B. subtilis, E. coli, P. aeruginosa, Staphylococcus aureus, Salmonella typhi and Enterobacter cloacae). The most active fraction was investigated to isolate compounds. The chemical compounds isolated from the ethyl acetate fraction were identified by gas chromatography-mass spectrometer, high performance liquid chromatography and liquid chromatography-mass spectrometer.Results: E. coli, P. aeruginosa, and C. albicans were the most susceptible. Less polar fractions exhibited stronger efficacy than polar ones, and ethyl acetate fraction proved to be the most potent. Zones of inhibition of hexane, chloroform and ethyl acetate fractions, and amoxil against C. albicans were 19.96, 22.01, 23.10 and 19.20 mm, respectively. Ethyl acetate faction was the most toxic to all the test microorganisms, with minimum inhibitory concentrations of 8.0, 7.8 and 7.78 μg/m L against P. aeruginosa, C. albicans and B. subtilis, respectively. Isolated compounds, limonene, 2'-hydroxyacetophenone, vanillin, naphthalenone, 2,3,3-trimethyl-2-(3-methylbuta-1,3-dienyl)-6-methylenecyclohexanone, 2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester, β-sitosterol, vitamin E, rutin, quercetin, lupeol, epigallocatechin, showed considerable antimicrobial activities against test microorganisms.Concl展开更多
基金supported by the State as part of the "Programme d’Investissement d’Avenir",under reference ANR10-IEED-0004-01
文摘The effects of two chlorinated chiral stationary phases, namely, Lux Cellulose-2 and Lux i-Cellulose-5, flow-rate, percentage of co-solvent and chemical structures of the compounds on retention and resolution were studied within this article. In this work a backpressure of 150 bar, a temperature of 40 ℃ and 10% of methanol as co-solvent were chosen as operating conditions. The optimum flow-rate was 2 mL/min. The percentage of co-solvent was studied between 7.5% and 15%.We have observed that 15% of methanol gave the best results for most of the compounds. For all the derivatives, the Lux Cellulose-2 provided better resolutions going from 1.50 to 3.59 compared with Lux i-Cellulose-5.
基金the vice chancellor for research of Shahid Chamran University,Ahvaz,Iran,for the research grant and financial support
文摘Objective:To investigate the isolation of marine antibiotic-producing bacteria from the Persian Gulf,as an untapped source for searching new natural antibiotics.Methods:Initially water and sediment samples were collected from 18 study sites in the some northern areas of Persian Gulf.All of the bacterial isolates using Marine Agar 2216 were inoculated into Marine broth and incubated on a rotary shaker at 28℃for 2-7 days.Bioactivily of their ethyl acetate extract was assessed at 100 mg/mL concentration in disc diffusion method against 6 gram-positive and 5 gram-negative bacteria.Synthetic antibiotics were used as control.Results:Altogether,46 bacterial colonies were isolated.Only one isolate from a marine sediment sample collected at a depth of 10 m,identified as Pseudomonas aeruginosa PG-01,was exhibited the capability of antibiotic production.The obtained raw extract from intended bacterium was effective against all tested gram positive bacteria while gram negative bacteria were resistance.Methicillin resisitant Stapuylococcus aureus(MRSA),Streptococcus pyogenes(S.pyogenes).Staphylococcus epidermidis (S.epidermidis) and Bacillus cereus(B.cereus) were the most sensitive strains.All of tested pathogens were multidrug resistant.The antibacterial compound from this bacterium was active even at 120℃.The optimized temperature and time for antibacterial metabolite production were 37℃and 72 hrs,respectively.Conclusions:Considering the antibacterial effect of Pseudomonas aeruginosa PG-01 especially against MRSA,it can be regarded the intended bacterium as a valuable strain and can give hope for treatment of diseases caused by multidrug resistant bacteria.
基金Supported by Higher Education Commission(HEC)of Pakistan as part of the project No.20-1986/R&D/11
文摘Objective: To study the antibacterial and antifungal activities of methanolic extract of roots of Carissa opaca and its fractions in hexane, chloroform, ethyl acetate, n-butanol and water, and the isolated compounds.Methods: The zones of inhibition of the samples against test microorganisms were determined by agar well diffusion method. Minimum inhibitory concentrations of the samples were determined by agar well dilution method. Test microorganisms included four standard bacteria [Bacillus subtilis ATCC 6633(B. subtilis), Escherichia coli ATCC 8739(E. coli), Pseudomonas aeruginosa ATCC 9027(P. aeruginosa), and Staphylococcus aureus ATCC 6538], two standard fungi [Candida albicans ATCC 10231(C. albicans)] and Aspergillus niger, and six clinical isolates(B. subtilis, E. coli, P. aeruginosa, Staphylococcus aureus, Salmonella typhi and Enterobacter cloacae). The most active fraction was investigated to isolate compounds. The chemical compounds isolated from the ethyl acetate fraction were identified by gas chromatography-mass spectrometer, high performance liquid chromatography and liquid chromatography-mass spectrometer.Results: E. coli, P. aeruginosa, and C. albicans were the most susceptible. Less polar fractions exhibited stronger efficacy than polar ones, and ethyl acetate fraction proved to be the most potent. Zones of inhibition of hexane, chloroform and ethyl acetate fractions, and amoxil against C. albicans were 19.96, 22.01, 23.10 and 19.20 mm, respectively. Ethyl acetate faction was the most toxic to all the test microorganisms, with minimum inhibitory concentrations of 8.0, 7.8 and 7.78 μg/m L against P. aeruginosa, C. albicans and B. subtilis, respectively. Isolated compounds, limonene, 2'-hydroxyacetophenone, vanillin, naphthalenone, 2,3,3-trimethyl-2-(3-methylbuta-1,3-dienyl)-6-methylenecyclohexanone, 2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester, β-sitosterol, vitamin E, rutin, quercetin, lupeol, epigallocatechin, showed considerable antimicrobial activities against test microorganisms.Concl
