IN VITRO ANTIMICROBIAL ACTIVITY OF MARINE ACTINOBACTERIA ISOLATES FROM PULICAT LAKE, TAMIL NADU, INDIA

Abstract

ABSTRACT
Objectives: The present investigation is undertaken with an aim to check the antimicrobial potential of marine Actinobacteria isolated from marine
sediment samples collected from Pulicat Lake, Tamil Nadu.
Methods: In this study, various physical and chemical pretreatment methods were used for selective isolation of Actinobacteria including air drying,
incubation of soil samples with calcium carbonate, incorporation of antibacterial, antifungal antibiotics in the media and plating on Actinobacteriaspecific
media.
A
combination
of such
methods
facilitated
isolation
of slow
growing
Actinobacteria
with a simultaneous reduction
of other
free-living

bacterial
and fungal
contaminants. The primary and secondary screening
was
done to
ascertain the antimicrobial
potential
of these isolates.
Results: The results obtained from primary screening was about 110 isolates, were tested against Pseudomonas aeruginosa, Staphylococcus aureus,
Candida albicans, and Aspergillus niger, out of these, 31 isolates showed remarkable antimicrobial activity. Based on the results of primary screening,
31 isolates were subjected to secondary screening from which two isolates with a strong and broad spectrum of antimicrobial activity were selected
for further studies.
Conclusion: The present study is useful as the isolation of most of the antimicrobial compounds from different Actinobacteria species showed partial
resemblance to earlier reported antibiotic chemical structures. Further, chemical characterization of the isolated compound from producer isolates
may yield more effective analogs or hybrid bioactive molecules.
Keywords: Actinobacteria, Antimicrobial activity, Pulicat lake.