Antimicrobial activities of secondary metabolites and phylogenetic study of sponge endosymbiotic bacteria, Bacillus sp. at Agatti Island, Lakshadweep Archipelago

Abstract

Twenty-one species of sponges were recorded under the class of Demospongiae and Calcareous sponges of which 19 species were new to Agatti reef. A total of 113 Sponge endosymbiotic bacterial strains were isolated from twenty-one species of sponges and screened for antimicrobial activity. Five bacterial strains of sponge endosymbiotic bacteria (SEB) namely SEB32, SEB33, SEB36, SEB43 and SEB51 showed antimicrobial activity against virulent marine fish pathogens such as Vibrio alginolyticus, Vibrio vulnificus, Vibrio parahaemolyticus, Aeromonas salmonicida, Flavobacterium sp., Edwardsiella sp., Proteus mirabilis and Citrobacter brackii. The secondary metabolites produced by SEB32 from sponge Dysidea fragilis (Montagu, 1818) [48] was selected with broad range of antibacterial activity and subjected for production, characterization by series of chromatography techniques and spectroscopic methods. Based on the results of FT-IR and mass spectrometry, the active molecule was tentatively predicted as “Pyrrol” and the structure is Pyrrolo[1,2-a]pyrazine-1,4-dione, hexahydro- with molecular formula of C7H10N2O2. The LC50 of active molecule was 31 μg/ml and molecular weight of the metabolites was 154. The potential strain SEB32 was identified by gene sequence (GenBank Accession number JX985748) and identified as Bacillus sp. from GenBank database.

Bacterial isolates from bryozoan Pleurocodonellina sp.: Diversity and antimicrobial potential against pathogenic bacteria

“…Moreover, all bacterial genera related to those found in this study were reported as antimicrobial agents. Such products have been reported, such as marine Pseudoalteromonas (Bowmann 2007;Offret et al 2016), Halomonas (Bitzer et al 2006), Bacillus (Mondol et al 2013;Mohan et al 2016), and Virgibacillus (Arunachalam et al 2013). Since antibacterial features had been published for all members of related genera from this study, the diversity of active bacteria found may not be surprising.…”

Antagonistic activity of terrestrial <i>Streptomyces</i> sp. VITNK9 against Gram negative bacterial pathogens affecting the fish and shellfish in aquaculture

“…Antibacterial activity of actinomycetes against human as well as fish bacterial pathogens has been reported (Babuselvam et al 2016, Jenifer et al 2018. Mohan et al(2016) have reported on the antimicrobial activity of actinomycetes extracts against the fish bacterial pathogens. Antibacterial activity of actinobacterial isolates against A. hydrophila, A. sorbia and E. tarda has already been reported (Patil et al 2001).…”

Bacteria associated with tunicate, Polycarpa aurata, from Lease Sea, Maluku, Indonesia exhibiting anti-multidrug resistant bacteria

“…The family Bacillaceae showed a high percentage of antimicrobial activity against gram-positive and gramnegative bacteria in previous studies (Arunachalam and Appadorai 2013;Ayuningrum et al 2017). Bacilli produce a wide range of natural products, including lipopeptides, polypeptides, macrolactams, fatty acids, polyketides, and isocoumarins, with a series of bioactivities (Mondol et al 2013;Mohan et al 2016). On the other hand, a gramnegative bacterium, Vibrio algynoliticus TSC 10 belonged to family Vibrionaceace was isolated from the tunicate specimen 18-SMT-14.…”