Combinations of Tibetan tea and medicine food homology herbs: A new strategy for obesity prevention.

Obesity has become a significant global public health problem. Functional drinks have been an essential direction for obesity prevention research. The present study investigated the preventive effect and safety of winter melon and lotus leaf Tibetan tea (WLTT, a compound tea drink based on Ya'an Tibetan Tea and medicine food homology herbs) on obesity. The rats' hypercaloric high-fat diet (HFD) obesity model was established to evaluate obesity prevention and explored the mechanism through intestinal flora regulation. The results showed that in obese rats with the intervention of WLTT (400, 800, and 1600 mg/kg BW), the body weight, fat accumulation, adipocyte cell size, serum lipid levels, and antioxidant enzyme activity (SOD, GSH-Px, and MDA) were progressively improved. 16S rRNA high-throughput sequencing showed that WLTT could improve intestinal flora disorders due to HFD, which significantly reversed the relative abundance of Firmicutes and the F/B ratio associated with an HFD, and significantly upregulated the relative abundance of Verrucomicrobia. At the genus level, the downregulation of the relative abundance of Akkermansia and unclassified_Lachnospiraceae groups, and the upregulation of the relative abundance of Romboutsia, Ruminococcus, Corynebacteriume, and Saccharibacteria_genera_incertae_sedis groups brought about by the HFD were significantly reversed. The results of the above experiments were compared favorably with those of a parallel experiment with Bi -Sheng -Yuan slimming tea (BSY, a functional drink based on green tea and medicine food homology herbs). Overall, the findings have provided that WLTT can prevent obesity owing to an HFD by regulating intestinal flora and has a good safety profile, and combinations of Tibetan tea and medicine food homology herbs could be a new option for obesity prevention.

Extraction Optimization, Physicochemical Characteristics, and Antioxidant Activities of Polysaccharides from Kiwifruit (Actinidia chinensis Planch.).

In order to evaluate effects of extraction techniques on the physicochemical characteristics and antioxidant activities of kiwifruit polysaccharides (KPS), and further explore KPS as functional food ingredients, both microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE) were optimized for the extraction of KPS. Furthermore, the physicochemical structures and antioxidant activities of KPS extracted by different techniques were investigated. The optimal extraction conditions of UAE and MAE for the extraction of KPS were obtained by response surface methodology. Different extraction techniques significantly affected the contents of uronic acids, molecular weights, molar ratios of constituent monosaccharides, and the degree of esterification of KPS. Results showed that KPS exhibited remarkable DPPH and ABTS radical scavenging activities, and reducing power. The high antioxidant activities observed in KPS extracted by the MAE method (KPS-M) might be partially attributed to its low molecular weight and high content of unmethylated galacturonic acid. Results suggested that the MAE method could be a good potential technique for the extraction of KPS with high antioxidant activity, and KPS could be further explored as functional food ingredients.

Phenolic Profiles, Antioxidant Capacities, and Inhibitory Effects on Digestive Enzymes of Different Kiwifruits.

In order to obtain high-quality kiwifruits with health-promoting characteristics, physicochemical properties, phenolic profiles, antioxidant capacities, and inhibitory effects on digestive enzymes (pancreatic lipase and α-glucosidase), of fourteen different types of kiwifruit obtained from China were systematically investigated and compared. Noticeable variations in the fruits' physicochemical properties and phenolic profiles were observed among them. The total phenolic content of Actinidia chinensis cv. Hongshi, A. chinensis cv. Jinshi, and A. chinensis cv. Jinlong were 16.52 ± 0.26 mg GAE/g DW (dry weight), 13.38 ± 0.20 mg GAE/g DW, and 11.02 ± 0.05 mg GAE/g DW, respectively, which were much higher than those of the other tested kiwifruits. According to high performance liquid chromatography (HPLC) analysis, phenolic compounds, including procyanidin B1, procyanidin B2, (-)-epicatechin, chlorogenic acid, gallic acid, and quercetin-3-rhamnoside, were found to be the major compounds in kiwifruits, while procyanidin B1, procyanidin B2, and chlorogenic acid were the most abundant phenolic compounds. Furthermore, all the tested kiwifruits exerted remarkable antioxidant capacities and inhibitory effects on pancreatic lipase and α-glucosidase. Indeed, A. chinensis cv. Hongshi, Actinidia chinensis cv. Jinshi, and Actinidia chinensis cv. Jinlong exhibited much better antioxidant capacities and inhibitory effects on digestive enzymes than those of the other tested kiwifruits. Particularly, A. polygama showed the highest inhibitory activity on α-glucosidase. Therefore, Actinidia chinensis cv. Hongshi, Actinidia chinensis cv. Jinshi, and Actinidia chinensis cv. Jinlong, as well as A. polygama could be important dietary sources of natural antioxidants and natural inhibitors against pancreatic lipase and α-glucosidase, which is helpful for meeting the growing demand for high-quality kiwifruits with health-promoting characteristics in China.