Monoalkyl esters of fatty acids commonly known as biodiesel are synthesized from triglycerides by the transesterification reaction with monohydric alcohol, usually methanol or ethanol. Biodiesel is an attractive alternative fuel for diesel engines because of its renewability, biodegradability, and nontoxicity. Several methods/approaches have been developed for analyzing the fuel quality of biodiesel. Mainly chromatographic techniques [e.g., gas chromatography (GC), high-performance liquid chromatography, etc.] are being used for the analysis of biodiesel. The equation for quantification of the transesterification reaction using proton nuclear magnetic resonance ( 1 H NMR) is available in the literature, wherein methanol/ethanol are being used as an acyl acceptor. In the present work, we report the equation based on 1 H NMR, which can be used for the quantification of the transesterification reaction, using other primary alcohols as an acyl acceptor. Simultaneously, we have also studied the effect of the chain length of alcohols on the extent of transesterification using whole cell catalysts. Transesterification was enhanced using butanol (67%) and pentanol (76%), followed by a decrease with hexanol (66%) and octanol (56%). The correlation coefficient (R 2 ) between GC and 1 H NMR methods was 0.97. The results obtained by the new 1 H NMR equation proposed in this work were well-correlated with GC analysis of the same samples.

No abstract

No abstract

Background: Fragrances are the collection of unlike functional assemblies, most likely alcohols, esters, aldehydes, ketones, and acids in organic products/hydrocarbons. Short-chain aliphatic fragrance esters have immense applications as flavors in the food, pharmaceutical and cosmetic industries and also have remarkable commercial significance in cosmetics and personal care products like perfumes, face creams, shampoos, soaps, lotions, jams, jellies, etc. Objective: This study aimed to synthesize short-chain fragrance esters using a whole-cell lipase catalyst from Aspergillus flavus (RBD-01). Method: The present study emphasizes the synthesis of artificial flavoring compounds by using a whole-cell biocatalytic process, which can have wide significance. Herein, the preparation of ethyl alkanoates (ethyl propanoate to ethyl decanoate) was performed to investigate the flavors and fragrance excellence. The biomass from Aspergillus flavus (RBD-01) was used as a catalyst to facilitate the remarkable esterification activities towards the synthesis of important aroma esters with the help of a series of short-chain acids and alcohols. Result: The ethyl hexanoate (4) among all synthesized alkanoates was found to have a fruity fragrance with a good conversion rate. Further synthesized alkyl hexanoates (4A-4I) were found to have good fruity/pineapple/berry flavors and significant aroma quality. Conclusion: These results implied that whole-cell lipase of Aspergillus flavus (RBD-01) is a promising biocatalyst in the production of flavor aroma esters and can boost production in the food/cosmetic manufacturing industries. result: The ethyl hexanoate (4) among all synthesized alkanotes was found fruity fragrance with good conversion rate. Further synthesized alkyl hexanoates (4A-4I) were found good fruity/pinapple/berry flavors and significant aroma quality.

No abstract