Production of vanillin from trans-ferulic acid isolated from rice bran

Abstract

Rice bran is byproduct from rice agricultural industry in Thailand. It constitutes trans-ferulic acid as one of major components. trans-Ferulic acid is a phenolic compound that can be converted to vanillin by ozonolysis. This transformation would increase value of agricultural byproduct such as rice bran. The objective for this project is to find the most suitable reaction conditions for ozonolysis of trans-ferulic acid to yield vanillin. Several participating solvents such as methanol, ethanol, and water were examined as reaction medium for ozonolysis. It was found that using ethanol as solvent for ozonolysis is most efficient since ozonide intermediate was not detected during the reaction thus it avoided the use of dimethyl sulfide for reductive workup. Moreover, ozonolysis using ethanol as solvent provided vanillin in quantitative yield. Next, extraction of trans-ferulic acid from rice bran using Soxhlet extraction was carried out. After purification, the result showed that the major products were fatty acids such as palmitic acid, oleic acid, and linoleic acid instead of the desired transferulic acid. Further study needed to be carried out in order to achieve the extraction of transferulic acid from rice bran.