Canadian Food and Wine Institute, Niagara College, 135 Taylor Road, Niagara-on-the-Lake, Ontario L0S 1J0, Canada; School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
Division of Engineering Science, Faculty of Applied Science and Engineering, University of Toronto, 35 St. George Street, Toronto, Ontario M5S 1A4, Canada.
Food Res Int. 2022 Apr;154:110899. doi: 10.1016/j.foodres.2021.110899. Epub 2021 Dec 15.
Pu-erh tea is post-fermented sun-dried tea leaves of Camellia sinensis (Linn.) var. assamica (Masters) Kitamura plant, native to Yunnan, China. Pu-erh tea is a highly prized commodity with unique aroma and taste and multiple health effects. This review overviews the chemical constituents, tentative bioactive compounds and their mechanisms responsible for bioactivities of Pu-erh tea. The bioactivities include antioxidative, antimutagenic, antimicrobial, laxative and neuroprotective activities, and controlling or preventing hypercholesterolemia, hyperglycemia, obesity, diabetes, osteoporosis and Alzheimer's disease. Limited human trials hardly convince the claimed therapeutic efficiency of Pu-erh tea. Raw and ripened Pu-erh tea possess their respective sensory characteristics, chemical and microbial diversities. Chemical and biological differences between Pu-erh and other tea types could be explained by different extents of their respective processing-induced compound transformations. Undesirable heavy metals, mycotoxins and other biocontaminants detected in Pu-erh tea relate to growing conditions of tea plantations, processing and storage conditions. Chemistry- and nutrition-derived mechanisms for tea pricing are lacking. Decontamination strategies and future studies for quality improvement of Pu-erh tea are recommended.
普洱茶是中国云南地区原产的晒青茶，是经过后发酵的茶。普洱茶是一种具有独特香气和口感且有多种保健作用的珍贵商品。本文综述了普洱茶的化学成分、潜在生物活性化合物及其生物活性的作用机制。这些生物活性包括抗氧化、抗突变、抗菌、通便和神经保护作用，以及控制或预防高胆固醇血症、高血糖、肥胖、糖尿病、骨质疏松症和阿尔茨海默病。有限的人体试验很难证明普洱茶声称的治疗效果。生普和熟普具有各自的感官特征、化学成分和微生物多样性。普洱茶与其他茶类之间的化学和生物学差异可以用它们各自加工诱导的化合物转化程度来解释。在普洱茶中检测到的重金属、真菌毒素和其他生物污染物与茶园的生长条件、加工和储存条件有关。茶叶定价的化学和营养机制尚不清楚。建议采取去污策略和进一步研究来改善普洱茶的质量。
