Abstract: 3-Phenyllactic acid (PLA) is a high-value organic acid and also an important metabolite of some lactic acid bacteria with effective activities against a wide range species of gram-positive and gram-negative bacteria and some fungi. This interesting compound has potential applications in chemical and pharmaceutical industry, biotechnology, and material and food areas as either a potential alternative to the chemical preservatives or a promise key monomer for the preparation of new polymer materials of poly(phenyllactic acid)s by polymerization, which have enhanced properties compared with those of wide-used poly(lactic acid)s. The present review summarizes the advances in the antibacterial activities, the available microbial strains, the biotransformation and biosynthesis, the metabolic pathways within these microorganisms, and the downstream separation and purification methods of PLA. The bacteria strains are crucial to the bioconversion or biosynthesis production of PLA. Although the recombinant engineering strains always have high conversion efficiencies, the construction of these strains is complex. The screening of new, safe strains with satisfactory bioconversion properties from natural resources is of great importance and an interesting approach for the enhancement of the bioconversion efficiency and the final concentration of PLA in the biotransformation broth. Moreover, the separation of PLA from the fermentation or biotransformation feedstocks is mostly focused on the laboratory scale, which cannot match industrial requests. Further investigations on the novel isolation and purification techniques are still needed.

Key words: phenyllactic acid, biosynthesis, fermentation, separation, microorganism strain

摘要： 苯乳酸是一种高值有机酸和新型的天然防腐剂，可由乳酸菌等多种微生物代谢产生。苯乳酸有着较为宽广的抑菌谱，对大多数革兰氏阳性、阴性菌和真菌都有明显的抑菌作用，不仅作为天然抑菌剂可替代化学合成的防腐剂，而且可经聚合反应合成聚苯乳酸新型高分子材料，作为聚乳酸高分子的替代物。因此，苯乳酸在化工、制药、生物、材料和食品等领域有广阔的应用前景。本文从苯乳酸抑菌特性、微生物菌株、转化合成、代谢途径及下游分离纯化等方面，简述了其生物转化合成和分离的研究现状。微生物菌株是苯乳酸合成的关键，基因工程菌的转化能力虽然高效，但构建工程菌较复杂；从自然环境中筛选安全优良的菌株，可以简化转化合成过程，提高转化率和料液中苯乳酸的浓度；苯乳酸的分离纯化还处于实验室的规模，有待进一步探索以达到工业化的要求。

关键词: 苯乳酸, 生物合成, 发酵, 分离, 微生物菌株