Microbiome-Guided Exploration of the Microbial Assemblage of the Exotic Beverage "Insect Tea" Native to Southwestern China

Insect tea originated from ethnic minority regions in Southwest China: A review on the types, traditional uses, nutrients, chemistry and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Insect tea is a special non-Camellia tea produced from the feces of insects in ethnic minority regions in Southwest China. Insect tea was recorded to have the traditional functions to treat summer heat, dampness, digestive disturbance, excessive phlegm, shortness of breath and otitis, etc. AIM OF THIS STUDY: This review provides an updated and comprehensive review of insect tea on the tea types, host plants, tea-producing insects, producing process, traditional uses, nutritional values, chemistry, pharmacological activities, biological safety and toxicity. Moreover, the general challenges and the possible suggestions on insect tea in future were also discussed.

MATERIALS AND METHODS

The relevant literature on insect tea was obtained from scientific database, including Elsevier, PubMed, Springer, Wiley, Web of Science, Google Scholar, SciFinder, China National Knowledge Infrastructure (CNKI), Baidu Scholar, Wanfang Database, etc. In addition, pertinent information available in Ph.D theses, MSc. dissertations, books, records, and some classical Chinese herbal literature were also included. The references cited in this review were up to September 2022.

RESULTS

Insect tea has been traditionally used as popular beverage with various medicinal functions in the ethnic minority regions in Southwest China for centuries. At present, ten types of insect teas are recorded in different regions. Ten species tea-producing insect and fifteen species host plants are used to in the production of the tea. Insect teas were rich in various nutrients including proteins, carbohydrates, fat, minerals, dietary fiber and Vitamins. A total of 71 compounds have been isolated from insect teas, mainly including flavonoids, ellagitannins, chlorogenic acids and other phenolic compounds as well as the alkaloids. Modern studies demonstrated that insect tea had a variety of pharmacological activities in vitro and in vivo, such as anti-diabetic, lipid-lowing and anti-hypertensive, hepato-protective, gastro-intestinal promoting, anti-cancer, anti-mutagenic, antioxidant, and anti-aging activity, etc. Moreover, existing experimental results showed that insect teas are non-toxicity and biological safety.

CONCLUSION

Insect tea is a unique and niche product originated in the ethnic minority regions of Southwest China with various health-promoting benefits. Phenolics including flavonoids, ellagitannins, chlorogenic acids were reported as the main chemical constituents identified from insect tea. Multiple pharmacological activities of insect tea have been reported, which indicated that it had great potential for further development and application as drugs and health-promoting products. However, more studies on the tea-producing insects, host plants, chemistry and pharmacological activity of insect tea, as well as the toxicology should be further investigated.

Determination of Polyphenols in Ilex kudingcha and Insect Tea (Leaves Altered by Animals) by Ultra-high-performance Liquid Chromatography-Triple Quadrupole Mass Spectrometry (UHPLC-QqQ-MS) and Comparison of Their Anti-Aging Effects

Ilex kudingcha C.J. Tseng tea and insect tea, as traditional Chinese teas, are favored for their original craftsmanship, unique flavor, and biological functionality. In this study, ultra high-performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-QqQ-MS) was used to analyze the bioactive components of the extracts of Ilex kudingcha and insect tea, and D-galactose-induced aging mice were used to compare the in vivo anti-aging effects of Ilex kudingcha and insect tea extracts. The results were remarkable, UHPLC-QqQ-MS analysis showed that ITP contains 29 ingredients, while IKDCP contains 26 ingredients. However, due to the large differences in the content of the main chemical components in IKDCP and ITP, the effects are equally different. At the same time, the in vivo research results suggesting that the anti-aging effects of IKDCP and ITP (500 mg/kg) include the regulation of viscera indices of major organs; improvement in liver, skin, and spleen tissue morphology; decreased production of inflammatory cytokines; up regulation of SOD, CAT, GSH, GSH-PX, and T-AOC and down regulation of NO and MDA levels in serum and liver tissue; reductions in the concentration of pro-inflammatory factors, and increases in the concentration of anti-inflammatory factor. RT-qPCR and western blot assay also showed that IKDCP and ITP affect anti-aging by regulating the gene and protein expression of GSH-PX, GSH1, SOD1, SOD2, and CAT. The overall results indicate that ITP is more effective in treating oxidative damage in aging mice induced by D-galactose. Thus, ITP appears to be an effective functional drink owing to its rich nutritional components and anti-aging activities.