Microbial secondary metabolites are one of the immense
reservoirs of natural chemical diversity with potent biological activity.
Actinomycetes, specifically members of the genus Streptomyces, have the ability
to produce potential secondary metabolites possessing antimicrobial properties,
including beta-lactams, macrolides, aminoglycosides, etc. The production of
secondary metabolites by Streptomyces can be enhanced by altering nutritional
and culture parameters. The aim of the present work is to evaluate cultural
parameters influencing the production of bioactive secondary metabolites by
Streptomyces cinnamonensis VLCH-1 isolated from mangroves located at
Machilipatnam of Andhra Pradesh, India. Employing different pretreatment
techniques as well as culture media, 50 actinobacterial strains were isolated
from mangrove sediments. All the strains were screened for their ability to
produce bioactive metabolites. Among them, one strain exhibited broad-spectrum
antagonistic activity. It was identified as Streptomyces cinnamonensis VLCH-1
based on cultural, morphological, physiological and molecular approaches. To
enhance the production of bioactive metabolites by this strain, attempts are
made to optimise culture conditions. High antimicrobial metabolite production was
obtained from six-day-old culture grown in ISP-2 (yeast extract, malt extract,
dextrose) broth. The strain productivity was improved by amending the culture
medium with dextrose (1%), tryptone (1%) and K2HPO4 (0.50%) as carbon, nitrogen
and mineral sources. NaCl @3% supported good growth as well as enhanced the
production of bioactive metabolites. The secondary metabolites produced by the
strain under optimal conditions showed strong antagonistic activity against
pathogenic Gram-positive bacteria (Staphylococcus aureus, Bacillus megaterium),
Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa), and Candida
albicans. The study suggested that actinobacteria from unexplored mangrove
habitats of the south coast of Andhra Pradesh serve as a source for
antimicrobial compounds.
Author(s) Details
Ch. Chiranjeevi
Department of Botany and Microbiology, Acharya Nagarjuna University,
Guntur-522510, Andhra Pradesh, India.
K. Nagaraju
Department of Botany and Microbiology, Acharya Nagarjuna University, Guntur-522510,
Andhra Pradesh, India.
M. Vijayalakshmi
Department of Botany and Microbiology, Acharya Nagarjuna University,
Guntur-522510, Andhra Pradesh, India.
Please see the book here :- https://doi.org/10.9734/bpi/mbrao/v5/6571
No comments:
Post a Comment