Leonard William, Zhang Pangzhen, Ying Danyang, Adhikari Benu, Fang Zhongxiang
School of Agriculture and Food, The University of Melbourne, Parkville, VIC 3010, Australia.
CSIRO Agriculture and Food, 671 Sneydes Road, Werribee, VIC 3030, Australia.
Biotechnol Adv. 2021 Jul-Aug;49:107763. doi: 10.1016/j.biotechadv.2021.107763. Epub 2021 May 4.
Phenolics are a group of compounds derived from plants that have displayed potent biological activities and health-promoting effects. Fermentation is one of the most conventional but still prevalent bioprocessing methods in the food industry, with the potential to increase phenolic content and enhance its nutritive value. This review details the biotransformation of different classes of phenolics (hydroxycinnamic and hydroxybenzoic acids, flavonoids, tannins, stilbenoids, lignans, alkylresorcinols) by various microorganisms (lactic acid bacteria, yeast, filamentous fungi) throughout the fermentation process in plant-based foods. Several researchers have commenced the use of metabolic engineering, as in recombinant Saccharomyces cerevisiae yeast and Escherichia coli, to enhance the production of this transformation. The impact of phenolics on the metabolism of microorganisms and fermentation process, although complex, is reviewed for the first time. Moreover, this paper highlights the general effect of fermentation on the food's phenolic content, and its bioaccessibility, bioavailability and bioactivities including antioxidant capacity, anti-cancer, anti-diabetic, anti-inflammation, anti-obesity properties. Phenolics of different classes are converted into compounds that are often more bioactive than the parent compounds, and fermentation generally leads to a higher phenolic content and antioxidant activity in most studies. However, biotransformation of several phenolic classes is less studied due to its low concentration and apparent insignificance to the food system. Therefore, there is potential for application of metabolic engineering to further enhance the content of different phenolic classes and bioactivities in food.
酚类化合物是一类源自植物的化合物，已显示出强大的生物活性和促进健康的作用。发酵是食品工业中最传统但仍普遍使用的生物加工方法之一，具有增加酚类含量和提高其营养价值的潜力。本文综述了在植物性食品的整个发酵过程中，各种微生物（乳酸菌、酵母、丝状真菌）对不同类别的酚类化合物（羟基肉桂酸和羟基苯甲酸、黄酮类化合物、单宁、芪类化合物、木脂素、烷基间苯二酚）的生物转化。一些研究人员已经开始使用代谢工程，如重组酿酒酵母和大肠杆菌，来提高这种转化的产量。酚类化合物对微生物代谢和发酵过程的影响虽然复杂，但首次进行了综述。此外，本文强调了发酵对食品中酚类含量及其生物可及性、生物利用度和生物活性（包括抗氧化能力、抗癌、抗糖尿病、抗炎、抗肥胖特性）的总体影响。在大多数研究中，不同类别的酚类化合物会转化为通常比母体化合物更具生物活性的化合物，并且发酵通常会导致更高的酚类含量和抗氧化活性。然而，由于几种酚类化合物的浓度较低且对食品体系的影响不明显，对其生物转化的研究较少。因此，代谢工程有潜力进一步提高食品中不同酚类化合物的含量和生物活性。
