* To whom all correspondence should be addressed. E-mail: chellaramvtmt@gmail.com JOURNAL OF PURE AND APPLIED MICROBIOLOGY, Sept. 2015. Vol. 9(3), p. 2459-2464 Insecticidal Activity of an Epibiotic Bacillus kochii from Gorgonian Coral, Junceella juncea (Pallas, 1766) C. Chellaram 1 * and A. Alex John 2 1 Department of Biomedical Engineering, Vel Tech Multitech, Chennai-600062. Tmailnadu India. 2 Research Scholar, St. Peter's University, Avadi. Chennai-600062. Tamilnau. India. (Received: 01 April 2015; accepted: 10 June 2015) Aim of the research is to isolate and identify bacteria from sea fan corals and analyzing its insecticidal activity against storage pest, Sitophilus oryzae. The bacterial strain WP3, was isolated from the coral Junceella juncea from Tuticorin coast, Gulf of Mannar region, south east coast of India. Insecticidal activity of pure compounds was assayed by bench top assay method. Different solvent extracts (hexane, acetone and methanol) of the culture broth (WP3) was done and its activity was noted. Methanol extract showed minimum LC 50 when compared to acetone and hexane extracts. High performance liquid chromatography (HPLC) trace confirmed the presence of active compounds. Mass spectrophotometry (MALDI-TOF) analysis has shown that the mass of the molecules ranged from 1225 Da to 1927 Da. 16S rRNA sequencing and phylogenetic identification was done and the stain was identified to fell under the genera Bacillus. The result shows that the marine bacteria isolated from Junceella juncea corals are a potential source of novel bioactive agents and other natural products that may be utilized as pesticides. Key words: Junceella juncea, Bacillus kochii, Sitophilus oryzae, Mass spectrophotometry. According to a report by Food and Agriculture Organization (FAO), 120 billion dollars were lost worldwide due to 20–40% decrease in crop yield, because of the attack from pathogenic organisms and insect pests (Zhou et al., 2010). To ensure the constant and high productivity of crops, vast amount of pesticide were applied to control the pests. This has resulted in causing serious environmental pollution and accumulation of insecticide residues. Also, inducing a wide range of pesticide resistance was done (Jiang et al., 2000). For better productivity without ill effects, biopesticides have gained increased attention and interest among those concerned with developing environmentally friendly and safe integrated crop management (Leonard et al., 2000). At present, microbial insecticides are the main part of the bio- pesticide industry (Shi et al., 2000 and Xie et al., 1998). The taxonomic diversity of marine organisms is large as is their biochemical and behavioral diversity, this chemical diversity was found to contain pesticide substance close to DDT and Chlordane (Kennett et al., 1990). Microorganisms possess exceptionally rich sources of drugs, including antibiotics, immune-suppressants etc (Chellaram et al., 2011). However, these drugs have been produced from a very small range of world’s microbial diversity (Chelllaram et al., 2012). Actinomycetes have been found to be a best source of novel antibiotics and other bioactive compounds (Prem Anand, et al., 2012; Okami et al., 1979, Anbuselvi, et al., 2009; Prem Anand, et al., 2013 and Chellaram et al., 2013). The yield loss of crops was estimated to be 20 - 30%. An additional 10% of crop is lost due to post harvest storage and transportation (Duke et al., 1993). Cotton leafworm (Spodoptera littoralis), is considered one of the most affecting insect pests attacking crops, vegetables and fruit trees all over the world (Berlinger et al., 1997). It has the capability to develop resistance to most conventional insecticides. To prevent soil and