苯乳酸(phenyllactic acid,PLA)是近年来发现的新型生物防腐剂,可以有效抑制革兰氏阴性、阳性细菌和真菌的生长。乳酸菌(lactic acid bacteria,LAB)PLA是食品级的生物防腐剂。它的生物合成核心途径为:以苯丙氨酸(phenylalanine,Phe)为底物,α-酮戊二酸为氨基受体,经转氨反应生成苯丙酮酸(phenypyruvate,PPA),然后PPA经脱氢酶作用,还原生成PLA。PLA的分解代谢产物主要有二氢化二醇、1-溴-2,3苯甲烷等。除了受温度、p H和培养条件的影响外,PLA的合成代谢主要受到乳酸脱氢酶(lactic dehydrogenase,LDH)、氨基转移酶(aminotransferase,ATase)和三羧酸循环(tricarboxylic acid cycle,TCA)等的调控。文中综述了LAB PLA的生物合成和分解代谢途径以及与该途径相关的调控机制。

Phenyllactic acid( PLA) is a new type of biological preservative founded in recent years,which can effectively inhibit the growth of gram-negative,gram-positive bacteria and fungi. PLA of lactic acid bacteria( LAB) is generally recognized as the food-grade biological preservatives,and its biosynthesis core way is as follows: with phenylalanine as substrate and α-ketone amino as receptor,phenypyruvate( PPA) was produced through ammonia reaction and then reduced to PLA by dehydrogenase. The main metabolic products of PLA are dihydrodiol,1-bromo-2,3-phenylpropanes etc. In addition to the influences of temperature,p H and culture conditions,the constructive metabolism of PLA is mainly regulated by lactate dehydrogenase( LDH),aminotransferase( ATase) and tricarboxylic acid cycle( TCA) etc. This paper reviews the biosynthesis and catabolism pathways of LAB PLA and the regulation mechanisms related to these pathways.