Objective:To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.Methods:Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolic...Objective:To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.Methods:Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined.Antibacterial activity was carried out against different pathogens.Results:Totally4 different groups of fungi were isolated from the lichen Roccella montagnei.Among the four genera,Aspergillus niger(A.niger)is potential to produce chitosan(1.3 g/L)on the twelfth day of incubation.Glucose plays an important role in the pnjductivity of chitosan and the yield was maximum at 10%(1.93 g/L).Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli.Conclusions:In conclusion,our findings suggest that A.niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity.展开更多
The effect of culture conditions on the production of bioactive secondary metabolites by the endophytic fungus Arthrinium State of Apiospora Montagnei Sacc. was investigated. Culture broths were partitioned with ethyl...The effect of culture conditions on the production of bioactive secondary metabolites by the endophytic fungus Arthrinium State of Apiospora Montagnei Sacc. was investigated. Culture broths were partitioned with ethyl acetate and the resulting extracts were evaluated for antibacterial, antifungal, cytotoxic, and antiparasitic activities. The highest levels of activities were arisen from cultures cultivated at 30。C in modified Czapek medium. The best antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa (MIC 90 μg/ml), and against Aspergillus fumigatus (MIC 130 μg/ml) were found in extracts from cultures grown in medium containing 3.1% (w/v) sucrose and 0.1% (w/v) sodium nitrate at pH 4.0 after 9 days of incubation. Cultures grown in medium without modification also showed antiparasitic and antitumoral activities after 9 days at pH 4.0, antifungal activity against Candida albicans at pH 4.0 - 7.0 (MIC 140 μg/ml), but against A. fumigatus just after 27 days of incubation. A specific bioactive compound may have its production improved if the culture conditions parameters that affect or influence the production were known, which in turn makes the purification process easier.展开更多
基金supported by Ministry of Environment and Forests.Govt.of India(grant No.22-9/2008-CS-1)
文摘Objective:To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.Methods:Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined.Antibacterial activity was carried out against different pathogens.Results:Totally4 different groups of fungi were isolated from the lichen Roccella montagnei.Among the four genera,Aspergillus niger(A.niger)is potential to produce chitosan(1.3 g/L)on the twelfth day of incubation.Glucose plays an important role in the pnjductivity of chitosan and the yield was maximum at 10%(1.93 g/L).Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli.Conclusions:In conclusion,our findings suggest that A.niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity.
文摘The effect of culture conditions on the production of bioactive secondary metabolites by the endophytic fungus Arthrinium State of Apiospora Montagnei Sacc. was investigated. Culture broths were partitioned with ethyl acetate and the resulting extracts were evaluated for antibacterial, antifungal, cytotoxic, and antiparasitic activities. The highest levels of activities were arisen from cultures cultivated at 30。C in modified Czapek medium. The best antimicrobial activity against Escherichia coli and Pseudomonas aeruginosa (MIC 90 μg/ml), and against Aspergillus fumigatus (MIC 130 μg/ml) were found in extracts from cultures grown in medium containing 3.1% (w/v) sucrose and 0.1% (w/v) sodium nitrate at pH 4.0 after 9 days of incubation. Cultures grown in medium without modification also showed antiparasitic and antitumoral activities after 9 days at pH 4.0, antifungal activity against Candida albicans at pH 4.0 - 7.0 (MIC 140 μg/ml), but against A. fumigatus just after 27 days of incubation. A specific bioactive compound may have its production improved if the culture conditions parameters that affect or influence the production were known, which in turn makes the purification process easier.
