Possible Mechanisms of Dark Tea in Cancer Prevention and Management: A Comprehensive Review

Abstract

Tea is one of the most popular drinks in the world. Dark tea is a kind of post-fermented tea with unique sensory characteristics that is produced by the special fermentation of microorganisms. It contains many bioactive substances, such as tea polyphenols, theabrownin, tea polysaccharides, etc., which have been reported to be beneficial to human health. This paper reviewed the latest research on dark tea’s potential in preventing and managing cancer, and the mechanisms mainly involved anti-oxidation, anti-inflammation, inhibiting cancer cell proliferation, inducing cancer cell apoptosis, inhibiting tumor metastasis, and regulating intestinal flora. The purpose of this review is to accumulate evidence on the anti-cancer effects of dark tea, the corresponding mechanisms and limitations of dark tea for cancer prevention and management, the future prospects, and demanding questions about dark tea’s possible contributions as an anti-cancer adjuvant.

Plant growth-promoting rhizobacteria (PGPR) improve the growth and quality of several crops

“…Theanine is one of the important C/N metabolites, and the application of exogenous nitrogen can effectively increase the content of theanine [ 31 , 32 ]. Tea polyphenols, caffeine, antioxidants, refreshing and cardiovascular protection, and other health effects [ [33] , [34] , [35] , [36] ] are also important tea flavor substances, mainly reflected as ' astringent ' and ' bitter [ [37] , [38] , [39] ]. Cao et al inoculation of microbial fertilizers in acidic soils significantly increased the content of substances such as total amino acids, total proteins, and total sugars under greenhouse conditions [ 40 ].…”

Defense against oxidative stress in Caenorhabditis elegans by dark tea

“…Dark tea contains phytochemicals and macronutrients, also believed to be beneficial to animals (15). As a natural and harmless nutraceutical, it can be used as a nutritional supplement, food additive and medicinal ingredient (16,17).…”