Vanillin is used as an aroma and flavoring agent in the food, beverage, and cosmetic industries. Vanilla planifolia is the major source of natural vanillin with a market price of 1200–4000$ per kg. To fulfill the market demand, low price vanillin is synthesized chemically i.e., 15 $/kg but European and US legislation considers it unnatural and recommends biosynthesis by fermentation. Ferulic acid is the main and costly precursor for vanillin production. It is naturally present in lignin-enriched agricultural wastes. Therefore, the present study was designed to extract ferulic acid from banana peels and then convert it into biovanillin using Enterobacter hormaechei . Different fermentative parameters like substrate concentration, incubation period, pH, temperature, and agitation speed were optimized via submerged fermentation by varying one factor at a time. From 100 g of banana peels, 60 ± 0.35 mg ferulic acid was extracted and used as a substrate for biovanillin production. The maximum significant (p-value < 0.05) production of biovanillin i.e., 3.8 ± 0.14 g/L was observed by bioconversion of 7 g/L of ferulic acid at 24 h of incubation time, pH 7, 30 °C and agitation speed of 150 rpm. Identification of produced vanillin was done by FTIR and quantification by HPLC method. It was found to be 97% pure in comparison to the standard of Sigma-Aldrich. Hence, the fruit by-product i.e., banana peels served as a useful substrate for the biosynthesis of vanillin. These conditions can be further optimized on a pilot scale to commercialize the product. • Ferulic acid is naturally present in lignin enriched agricultural wastes. • Extraction of ferulic acid from banana peels was done and then converted to biovanillin using Enterobacter hormaechei. • Fermentation conditions were optimized via submerged fermentation by varying one factor at a time. • Identification of produced vanillin was done by FTIR and was found to be 97% by HPLC method. • First study on biovanillin production biotechnologically using banana peels as a ferulic acid source.
Read full abstract