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In view of the rising global problems of environment pollution and degradation, the present process provides a ‘green solution’ to the synthesis of higher esters of lubricant range, more specifically in the range C12-C36, using different combinations of acids and alcohols, in a single step reaction. The esters produced are biodegradable in nature and have a plethora of uses, such as in additives, as lubricating oils and other hydraulic fluids. The enzymatic esterification was performed using liquid (non-immobilized or free) lipase enzyme, without any additional organic solvent. Soluble lipase proves to be superior to immobilized enzymes as it is more cost effective and provides a faster process for the production of higher esters of lubricant range. An interesting finding was, that the lipase enzyme showed higher conversion rates with increasing carbon number of straight chain alcohols and acids. Reactions were carried out for the optimization of initial water concentration, temperature, pH of the substrate mixture and the chain length of the substrates. Under optimized conditions, the method was suitable to achieve ~ 99% conversion. Thus, the process provides an environment friendly, enzymatic alternative to the chemical route which is currently used in the industrial synthesis of lubricant components.

Among various renewable energy sources, the production of biofuels derived from algal lipids holds bright prospects. One of the major roadblocks in the successful commercialization of microalgal biofuels is the existing energy‐intensive lipid extraction. In the present investigation, an attempt is made to assess aqueous lipid extraction strategies from oleaginous Scenedesmus obliquus at a high solid loading of 15% (w/v). In this study, four surfactants and five enzymes are evaluated for cell disruption of S. obliquus. It is the first report citing cetyl pyridinium bromide as the most suitable cationic detergent for surfactant‐assisted extraction, with a lipid recovery as high as 31.4%. However, during the evaluation of enzyme‐based cell disruption, neutral protease emerges as the best biocatalyst resulting in a lipid recovery of ≈75%. Total lipid extraction is accomplished using a two solvent system comprising of water‐immiscible ethyl acetate, followed by chloroform addition. The study revalidates the fact that the biochemical composition of Scenedesmus sp. plays a vital role while identifying and formulating an efficient and green process for microalgal cell disruption for enhanced lipid extraction under aqueous conditions. Practical Applications: The results of the present study demonstrate that if the biochemical composition of any oleaginous algal cell wall is known, aqueous enzymatic lipid extraction can be employed rather than taking up the conventional route of drying followed by Soxhlet extraction. The combination of using the cheap sources of enzymes and water‐immiscible green solvents like ethyl acetate can be lucrative downstream procedures for the lipid recovery from wet algal biomass when compared to traditional procedures.