Distribution of actinobacteria in the near shore estuarine sediments along north coastal Andhra Pradesh, India

Abstract

The distribution of actinobacteria in the near shore sediments of eight estuaries in the north coastal Andhra Pradesh was investigated  in relation to physic-chemical parameters during May 2015 to May 2016.  Eleven media were used to culture the actinobacteria.  The study recorded 11 genera (Actinomyces, Actinoplanes, Kibdellosprangium, Microbispora, Micromonospora, Microtetraspora, Saccharomonospora, Saccharopolyspora, Streptomyces, Streptosporangium and  Thermomonospora) of actinobactera.  The study  registered the occurrence of 143  species of  Streptomyces of which,  79  species were recorded at Station 5 (Gosthani estuary). The species S.albus,  S.atroolivaceus, S.catenulae, S.griseus, S.olivaceous, S.bellus  and  S.psammoticus  are common species. Forty species were recorded only once during the study period. The  mean densities of Actinobacteria  and  the genus Streptomyces    at Station 5 (Gosthani estuary) were  36 x 10² cfu/g and  29 x 10² cfu/g respectively.  The medium Glucose Asparagine Agar supported maximum number of (6)  actionobacteria  genera. The  ISP 3 medium (Oat Meal Agar) harboured  maximum number (27) of Streptomyces species.  Majority (8) of the media supported Streptomyces albus.  Species diversity indices (Simpson’s Index  D : 0.513 to  0.643;   Shannon’s Index: 0.755  to  1.3;  Margalef’s  Index :0.303 to 1.058)  values were calculated. Four species exhibited moderate antibacterial activity. The distribution of actinobacvteria is discussed in relation to the physicochemical parameters investigated.