Objective:To isolate and screen Actinomycetes from Lagos Lagoon soil sediments for antibiotic production.Methods:Soil samples were collected from four different locations of Lagos Lagoon and were dried for 2 weeks.Act...Objective:To isolate and screen Actinomycetes from Lagos Lagoon soil sediments for antibiotic production.Methods:Soil samples were collected from four different locations of Lagos Lagoon and were dried for 2 weeks.Actinomycetes were isolated by serial dilution using spread plate method on starch casein and Kuster’s agar supplemented with 80μg/mL cycloheximide to prevent fungal growth.The plates were incubated at 28°C for 1-2 weeks.Isolates were selected based on their cultural characteristics as well as their Gram’s reaction and subcultured on same media for isolation and incubated at 28°C for 3 days.Pure cultures were maintained on nutrient agar slants at 4°C.Thereafter,they were inoculated into starch casein and Kuster’s broth media and incubated at 28°C for 8 days.The resulting crude extracts were screened for antimicrobial activity against the following microorganisms:methicillin resistant Staphylococcus aureus,Staphylococcus aureus ATCC 29213,Escherichia coli ATCC 29522,Pseudomonas aeruginosa ATCC 27853,Candida albicans and Enterococcus faecalis ATCC 29212.Coagulase-negative staphylococci isolated from HIV patients were also used(Staphylococcus warneri,Staphylococcus xylosus and Staphylococcus epidermidis).Extraction of secondary metabolites was carried out and analysed using gas chromatography-mass spectrometer.Results:All the isolates displayed varying antimicrobial activity against at least one of the test organisms.Himalomycin A was identified in the extract from isolate ULS7.The gas chromatography-mass spectrometer data analysis showed the antibiotic profile of these isolates.Conclusions:The isolate ULS7 was found to display the highest antimicrobial activity against the test organisms.展开更多
文摘Objective:To isolate and screen Actinomycetes from Lagos Lagoon soil sediments for antibiotic production.Methods:Soil samples were collected from four different locations of Lagos Lagoon and were dried for 2 weeks.Actinomycetes were isolated by serial dilution using spread plate method on starch casein and Kuster’s agar supplemented with 80μg/mL cycloheximide to prevent fungal growth.The plates were incubated at 28°C for 1-2 weeks.Isolates were selected based on their cultural characteristics as well as their Gram’s reaction and subcultured on same media for isolation and incubated at 28°C for 3 days.Pure cultures were maintained on nutrient agar slants at 4°C.Thereafter,they were inoculated into starch casein and Kuster’s broth media and incubated at 28°C for 8 days.The resulting crude extracts were screened for antimicrobial activity against the following microorganisms:methicillin resistant Staphylococcus aureus,Staphylococcus aureus ATCC 29213,Escherichia coli ATCC 29522,Pseudomonas aeruginosa ATCC 27853,Candida albicans and Enterococcus faecalis ATCC 29212.Coagulase-negative staphylococci isolated from HIV patients were also used(Staphylococcus warneri,Staphylococcus xylosus and Staphylococcus epidermidis).Extraction of secondary metabolites was carried out and analysed using gas chromatography-mass spectrometer.Results:All the isolates displayed varying antimicrobial activity against at least one of the test organisms.Himalomycin A was identified in the extract from isolate ULS7.The gas chromatography-mass spectrometer data analysis showed the antibiotic profile of these isolates.Conclusions:The isolate ULS7 was found to display the highest antimicrobial activity against the test organisms.
