The frequent cases of dengue incidences are leading cause of illness and death in urban areas and Aedes albopictus (Skuse) is a primary vector for Dengue transmission in India. Synthesis of leaf mediated silver nanoparticles especially with Pongamia pinnata is a potential substitute for the existing organophosphorus insecticides like Tenophos, malathion and fenthion etc., for mosquito control programme. The nanoparticles were characterized by UV-visible absorption spectrum, X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) and Transmission Electron Microscopy (TEM). Analysis of TEM showed that the synthesized silver nanoparticles are in spherical shape with average size of 20 nm. Further the XRD analysis confirms the nano-crystalline phase of silver with face centred cubic (FCC) crystal structure. GC-MS analysis elucidated the presence of two active ingredients, such as 9-Octadecenoic acid (Z) and n-hexadecanoic acid, which are the prominent substances considered as larvicide. Larvae were exposed to varying concentrations of plant extracts and synthesized silver nanoparticles for 24 hours. From the results, it is found that plant extracts showed moderate larvicidal effects but, the synthesized silver nanoparticles had found to be toxic to larvae at LC50 (0.25 ppm) and LC 90 (1 ppm).

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In the rapid growing world, need for biofuels has much increased due to the increasing cost and scarcity of the conventional fossil fuels.Biodiesel contains a mixture of fatty acids methyl esters which are derived from triacylglycerols. Oleaginous yeasts are considered as a potential source for the high lipid accumulation. The current research work focuses on the extraction of lipids from Cutaneotrichosporan curvatum BRV096 and optimization of its fermentation parameters for high lipid accumulation. Various fermentation parameters viz. carbon source, nitrogen source, temperature, pH, inoculum percentage and harvesting time were optimized. Shake ask batch trial taken with all the optimized parameters showed high biomass weight (61.2±3.4 g/L), lipid content (30.1±3.8 g/L) and lipid percentage (49.1±2.2). Total lipids extracted were analysed by using FTIR spectroscopy conrmed the presence of carbonyl and methyl groups which reveals the feasibility of conversion into biodiesel. Transesterication of lipids were carried out and biodiesel quality parameters i.e., viscosity (4.42 mm2/sec), specic gravity (0.869), cloud point (18.9oC), cetane number (60.4) and iodine number (12.7) were assessed. Research results obtained shows that optimized parameters can be efciently used in the high lipid production from oleaginous yeasts.