Enrichment method for the isolation of bioactive actinomycetes from mangrove sediments of Andaman Islands, India

Abstract

Various pre-treatment methods and three different media were employed for the isolation of bioactive actinomycetes from mangrove sediments of Andaman and Nicobar Islands, India. Sediments from four different sites of mangrove forest were collected and pre-treated by dry heat method, and the media were supplemented with cycloheximide 80 μg/mL and nalidixic acid 75 μg/mL. The mean actinomycetes population density in sediment samples were recorded as 22 CFU-10-6 /gm in KUA medium followed by 12 CFU-10-6 /gm in AIA medium and 8 CFU-10-6 /gm in SCA medium. A total of 42 actinomycetes were isolated, and all the isolates were evaluated for their antibacterial activity against pathogenic bacteria on two different media. Among 42 isolates tested, 22 species were found to be antibacterial metabolite producer against test bacteria namely, Staphylococcus aureus, Bacillus subtilis, Salmonella typhi and Klebsiella pneumoniae. Particularly, the actinomycete strains such as A101,

In-vitro antimicrobial activity of marine actinobacteria against multidrug resistance Staphylococcus aureus

“…Baskaran et al reports that starch casein agar, Kuster's agar was found to be good for isolation of marine actinobacteria population. However, in the present study the maximum number of colonies was isolated on AIA followed by kuster's agar [40] . Hence, the soil physicochemical properties may play a major role in the selection of isolation media.…”

Ecophysiology of Wild Plants and Conservation Perspectives in the State of Qatar

“…Many potential bacteria were isolated from mangrove ecosystem such as nitrogen-fixers, phosphate solubilizers, photosynthetic anoxygenic sulfur bacteria, methanogenic and methane oxidizing bacteria, which are involved in efficient nutrient recycling [79]. Also bacteria and fungi that either produce antibiotics [80,81] or resistant to antibiotics were isolated from mangrove ecosystem [82,83].…”

Actinobacteria Isolation from Metal Contaminated Soils for Assessment of their Metal Resistance and Plant Growth Promoting (PGP) Characteristics

“…Slow growing, melanotrophic actinobacteria Actinobacteria Isolating Agar (AIA) Minimal medium Fast and slow growing actinobacteria (Baskaran et al, 2011) Defined Propionate Medium (DPM) and Buffered Ammonium Propionate (BAP) Specific for Frankia species (Gtari et al, 2004) International Streptomyces Project (ISP) Media (1 to 9)…”

“…Actinobacteria Isolating Agar (AIA) has also been suggested as a selective medium for actinobacteria in sediments (Baskaran et al, 2011). The ISP (International Streptomyces Project) family media have been used for studying physiological characteristics of already isolated actinobacteria.…”

“…This treatment however, spares certain common fast growing bacteria namely Bacillus subtilis and Bacillus mycoides which invade plates very fast after sample inoculation (Williams and Davies, 1965). These bacilli persist even after oven treatment consisting for 15min at 65°C, which supposedly eliminates non sporulating bacteria and actinobacterial spores (Baskaran et al, 2011) (Table 1).…”