Abstract: Silicone oil is a reaction medium or separation medium, or both, for ester synthesis. Enzyme-catalyzed esterification is conducted in the silicone oil, with ester product soluble therein. Ester is separated from silicone by distillation. Esterification in silicone oil in conjunction with a simultaneous fermentation process, results in alcohol fermentation products flowing through the intervening silicone oil (serving as an oxygen barrier) to react with organic acid at an oil:aqueous interface, catalyzed by an enzyme (e.g., lipase, esterase). Ester solubility in silicone is leveraged for extraction, isolating catalyzed (metal, chemical or enzyme) ester reaction products from an original reaction (aqueous or organic) medium. Esters may be generated from alcohol fermented from organic matter of agricultural waste products, utilizing cheaply available silicone oil. Similarly, silicone oil may also be used to extract from a polar solvent (e.g.