Ferulic acid is a fraction of the phenolics present in cereals such as rice and corn as a component of the bran. Substantial amounts of waste bran are generated by the grain processing industry and this can be valorized via extraction, purification and conversion of phenolics to value added chemical products. Alkaline alcohol based extracted and purified ferulic acid from corn bran was converted to vanillic acid using engineered Pseudomonas putida KT2440. The strain was engineered by rendering the vanAB gene nonfunctional and obtaining the mutant defective in vanillic acid metabolism. Biotransformation of ferulic acid using resting Pseudomonas putida KT2440 mutant cells resulted in more than 95 ± 1.4% molar yield from standard ferulic acid; while the corn bran derived ferulic acid gave 87 ± 0.38% molar yield. With fermentation time of less than 24 h the mutant becomes a promising candidate for the stable biosynthesis of vanillic acid at industrial scale.

阿魏酸是谷类（例如米和玉米）中作为麸皮成分的酚类化合物的一部分。谷物加工行业产生了大量的废糠，可以通过酚类的提取，纯化和转化为增值化工产品来增值。使用工程化的恶臭假单胞菌KT2440将来自玉米麸皮的基于碱性醇的提取和纯化的阿魏酸转化为香草酸。通过使van AB基因失去功能并获得香草酸代谢缺陷的突变体，对该菌株进行了工程改造。静止恶臭假单胞菌对阿魏酸的生物转化KT2440突变细胞从标准阿魏酸产生的摩尔产率超过95±1.4％；玉米糠衍生的阿魏酸的摩尔产率为87±0.38％。由于发酵时间少于24小时，该突变体成为工业规模稳定生物合成香草酸的有希望的候选者。