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Four different actinomycetes were obtained from the sampling sites. The isolate AA1 isolated from Puducherry beach exhibited good antibacterial activity on primary screening when compared to the others and hence was chosen for further study. The isolate AA1 was Gram positive with smooth surface morphology and the spore chain morphology showed them to be simple rectus. When the isolate was grown on different media the ariel mycelia was mostly white while the substrate was cream/white. It was able to grow at a pH of 7 at 30°C and tolerate 7% NaCl. Maltose, lactose and xylose was used as the sole carbon source. The crude ethyl acetate extract of AA1 showed antibacterial activity against E.coli (9mm), S.aureus (7.5mm), P.mirabilis (7.7mm), P.aeruginosa (7mm) and K.pneumoniae (4.5mm) at a concentration of 3.5mg/ml. MIC of the crude extract of AA1 was 0.531mg/ml for E.coli and P.aeruginosa, 1.062mg/ml for S.aureus, 0.265mg/ml for P.mirabilis, and 2.125mg/ml for K.pneumoniae. The FT-IR Spectrum of the crude extract showed characteristic peaks at 3290.56cm-1, 1635.64cm-1 and 1016.49cm-1 corresponding to the following functional group such as alcohol (O-H), Alkene (C=C), Ether (C-O) respectively. The 16S rRNA gene sequences of the isolate AA1 revealed 100% similarity to Streptomyces lincolnensis. The restriction sites prediction of the 16SrRNA gene of Streptomyces lincolnensis showed restriction sites for Eco53KI, Bsr I, Hae II, Eco RV, EcoRI, EagI, Hinc II etc. The restriction site analysis showed GC content of 59% and AT content of 41%.

The present study investigates the phytochemical constituents, the antimicrobial, antioxidant activity, the functional groups by FT-IR and the presence of bioactive compounds by GC-MS analyses of leaves of Solanum torvum, rhizome of Acorus calamus and whole plant of Mollugo pentaphylla. The preliminary phytochemical analysis of the solvent extracts revealed the presence of alkaloids, flavonoids, steroids, proteins, carbohydrates, phenols, saponins, glycosides, coumarins, quinines. The solvent extracts showed antibacterial activity against E.faecalis, E.coli S.aureus, B.subtilis. K.pneumonia and C.albicans. The total phenolic content was 0.3430 GAE/g DW whereas, the total flavonoid content varied between 4.928 - 7.751mgQE/g DW. DPPH free radical scavenging activity of the diethyl ether extract of S. torvum recorded the IC50 at a concentration of 7.23µg/ml. In the hydrogen peroxide assay of the M. pentaphylla aqueous extract the IC50 value at a concentration of 3.295µg/ml was recorded. FT-IR studies showed the major functional groups alcohols, alkane, amines, aldehydes, alkyl halide and GC-MS studies showed 20 compounds with phytol being the major constituent.