Upadhyay Priya, Singh Nitesh K, Tupe Rasika, Odenath Annamma, Lali Arvind
DBT-ICT Centre for Energy Biosciences, Institute of Chemical Technology, Mumbai, India.
Department of Chemical Engineering, Institute of Chemical Technology, Mumbai, India.
Prep Biochem Biotechnol. 2020;50(4):341-348. doi: 10.1080/10826068.2019.1697935. Epub 2019 Dec 6.
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 KT2440. The strain was engineered by rendering the AB gene nonfunctional and obtaining the mutant defective in vanillic acid metabolism. Biotransformation of ferulic acid using resting 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.
阿魏酸是谷物（如大米和玉米）麸皮中所含酚类物质的一部分。谷物加工业会产生大量的废弃麸皮，通过提取、纯化酚类物质并将其转化为增值化学产品，可以实现这些麸皮的价值。使用工程改造的KT2440将基于碱性乙醇从玉米麸皮中提取和纯化的阿魏酸转化为香草酸。该菌株通过使AB基因失去功能并获得香草酸代谢缺陷型突变体进行工程改造。使用静止的KT2440突变体细胞对阿魏酸进行生物转化，标准阿魏酸的摩尔产率超过95±1.4%；而玉米麸皮衍生的阿魏酸的摩尔产率为87±0.38%。发酵时间少于24小时，该突变体有望成为工业规模稳定生物合成香草酸的候选菌株。
