title: Release kinetics of esterified p-coumaric acid and ferulic acid from rice straw in mild alkaline solution.
abstract: The release kinetics of esterified p-coumaric acid (PCA) and ferulic acid (FA) from rice straw under a mild alkaline condition were investigated to collect fundamental data for the design of a recovery process. The results showed that the straw size, NaOH concentration, and temperature were the key parameters governing release kinetics. The analysis demonstrated that FA is released considerably faster than PCA. The close relationship between lignin and the PCA dissolution indicates a reciprocal and/or simultaneous release. Moreover, PCA is broadly distributed in the lignin network but tends to be located more densely in the lignin fraction which is not easily solubilized by alkaline treatment. In contrast, the release of FA is strongly affected by removal of lignin fraction which is easily solubilized. These results suggest that the release kinetics are controlled by the accessibility of NaOH to their ester sites in the lignin/hemicellulose network, and by their localization.
authors.affiliation: Institute of Industrial Science, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8505, Japan. Electronic address: ngoclinh@iis.u-tokyo.ac.jp.
authors.forename: Tran Ngoc
authors.initials: TN
authors.lastname: Linh
authors.affiliation: Institute of Industrial Science, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8505, Japan.
authors.forename: Hirokata
authors.initials: H
authors.lastname: Fujita
authors.affiliation: Institute of Industrial Science, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8505, Japan.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Sakoda
mesh_terms: D000863:Antacids / Q000494:pharmacology; D002473:Cell Wall / Q000737:chemistry / Q000378:metabolism; D003373:Coumaric Acids / Q000493:pharmacokinetics*; D004952:Esters / Q000493:pharmacokinetics; D007700:Kinetics; D008031:Lignin / Q000032:analysis / Q000378:metabolism; D012275:Oryza / Q000737:chemistry / Q000378:metabolism*; D011134:Polysaccharides / Q000737:chemistry / Q000378:metabolism; D011422:Propionates; D012996:Solutions
chemical_list: D000863:Antacids; D003373:Coumaric Acids; D004952:Esters; D011134:Polysaccharides; D011422:Propionates; D012996:Solutions; C007916:hemicellulose; D008031:Lignin; C004999:ferulic acid; C495469:p-coumaric acid
keywords: Ferulic acid; Mild alkaline treatment; Release kinetics; Rice straw; p-Coumaric acid