Microbial polyketides are synthesized by serialized reactions of a set of enzymes called PKS with extraordinary structural diversity and an irregular distribution between strains and species, and they have been considered to play vital roles antimicrobial agents for pathogenic bacteria, fungi and also used as in pest control agents to kill insects and pests [16]. Spinosyns recovered Sapitinib price from microorganism showed potent insecticidal activities against many commercially significant species that cause extensive damage to crops

and other plants. They also exhibit activity against important external parasites of livestock, companion animals and humans [17]. Several microbial polyketides, such as avermectins and milbemycins, have been reported as potent insecticides against various insects and parasites. Furthermore, they are believed to be the biggest selling and arguably most effective acaricides and anthelmintics currently available [18]. Of the 7000 known polyketide structures, more than 0.3% has been commercialized [19]. selleckchem Given the importance and potential of these compounds, the discovery of microbial polyketides has drawn increasing attention. Conclusions In

conclusion, polyketide metabolite showed good antifeedant, larvicidal, pupicidal and growth inhibitory activities against H. armigera and S. litura. The results indicated that polyketide metabolite would be a potential insecticide. This study is the first report on antifeedant, larvicidal, pupicidal and growth inhibitory activities against H. armigera and S. litura. This metabolite could be used for the development of new insecticidal formulation for the management of field pests. Methods Isolation and identification of Streptomyces sp. AP-123 Streptomyces sp. AP-123 was isolated from Andra Pradesh coast of the Bay of Bengal, India. The 16S rDNA gene (check details accession number JQ283107) based phylogenetic affiliation was determined by using bioinformatics tools identified Streptomyces sp. AP-123

as Streptomyces isothipendyl sp. with 99% sequence similarity to Streptomyces flavogrecius (Figure 2). Figure 2 Phylogenetic tree based on 16S rDNA gene sequence showing the relationship between Streptomyces sp. AP-123 and species belonging to the genus Streptomyces was constructed using the neighbour-joining method. Bootstrapping values >50 are not mentioned [10]. Isolation and identification of polyketide metabolite Isolation of polyketide metabolite and its identification have already been described in our earlier manuscript [10]. Insect culture collection and monitoring Larvae of S. litura and H. armigera were collected from the farmers’ field in Kancheepuram district, Tamil Nadu. Insects were cultured by following the methods of Basker et al. [20]. Briefely, the collected H.