Sea buckthorn berries are rich in bioactive compounds and can be used for medicine and food. The variety and drying method used have an important influence on quality. In this study, different sea buckthorn varieties from China were selected and dried with four common drying methods. The total phenolic content (TPC), total flavonoids content (TFC), contents of 12 phenolic compounds and antioxidant capacity in vitro were analyzed. The results showed that the TPC, TFC and antioxidant activity of two wild sea buckthorn berries were higher than those of three cultivated berries, and for the same varieties, measured chemical contents and antioxidant activity of the freeze-dried fruit were significantly higher than those obtained with three conventional drying methods. In addition, forty-one compounds in sea buckthorn berry were identified by UPLC-PDA-Q/TOF-MS, most of which were isorhamnetin derivatives. Multivariate statistical analysis revealed narcissin and isorhamnetin-3-O-glucoside varied significantly in sea buckthorn berries of different varieties and with different drying methods; they were potential quality markers. Strong correlations were found between TPC, gallic acid and antioxidant capacity (p < 0.05). The results revealed how components and antioxidant activity varied in different sea buckthorn, which provides a valuable reference for quality control and further development and utilization of sea buckthorn.

Despite that colorectal cancer (CRC) is a severe global health problem, effective chemopreventive strategies against CRC are still lacking. Huang-qin tea (HQT), a healthy herbal tea, is prepared from the aerial parts of Scutellaria baicalensis Georgi and has been consumed in China for thousands of years. HQT contains abundant flavonoids, which display potent anticancer effects, but no research studies have investigated the cancer-preventive effects of HQT on CRC in vivo. Here, we found that HQT inhibits azoxymethane-induced aberrant crypt foci (ACF) formation in a preneoplastic colonic ACF rat model. The essential role of the gut microbiota in the chemopreventive effect of HQT on CRC in a pseudo-germ-free rat model was confirmed. Besides, HQT modulates inflammatory cytokine expression by significantly decreasing IL-1β, IL-6, IL-10, and TNF-α expression, and elevating IFN-γ production. 16S rDNA sequencing analysis indicated that HQT regulated the gut microbiota by increasing the abundance of beneficial bacteria (Lachnoclostridium, Alistipes, Roseburia, and Lactococcus) and reducing the levels of Bacteroides, Parasutterella, and unidentified_Clostridiales. Fecal metabolomics showed that HQT modulated the AOM-induced metabolomic disorder, and these altered metabolites were almost involved in the lipid metabolic pathways. The Spearman correlation analysis revealed a correlation between the gut microbiota and fecal metabolites. Collectively, these results suggested that HQT exerted beneficial effects on host health by inhibiting inflammation, and by regulating the gut microbiota profile and certain metabolic pathways. In conclusion, HQT inhibits AOM-induced ACF formation by modulating the gut microbiota composition and improving metabolomic disorders, indicating the potential of HQT as a functional beverage candidate for the prevention and treatment of CRC.