With the drastic changes in lifestyle, nonalcoholic fatty liver disease (NAFLD) has become a widespread health problem. Natural actives such as polyphenols have multi-target, multi-mechanism characteristics, and offer new opportunities for NAFLD treatment. This study established a high-fat diet (HFD)-induced NAFLD model in mice to investigate the molecular mechanism of Pandanus amaryllifolius Roxb. polyphenol extract (PAE) in alleviating NAFLD. The results showed that PAE significantly inhibited HFD-induced obesity, maintained glucose homeostasis, mitigated oxidative damage in liver tissue, and reduced liver steatosis. Moreover, PAE treatment remarkably reversed 16 endogenous DMs, and significantly affected glycerophospholipid metabolism, which increased the levels of phosphatidylcholine and phosphatidylethanolamine, and down-regulated choline and sn-glyceropl-3P. Further validation revealed that PAE was able to prevent NAFLD progression by regulating the AMPK/AKT/mTOR signaling pathway to enhance autophagy levels. Meanwhile, PAE treatment restored the balance of gut microbiota mainly by increasing the relative abundance of Bacteroidetes, decreasing the relative abundance of Firmicutes and the ratio of Firmicutes/Bacteroidetes. Overall, the findings highlight that the mechanism by which PAE alleviates NAFLD may be related to the regulation of the gut microbes and AMPK/AKT/mTOR signaling pathway, enriching the health-promoting effects of PAE on NAFLD.

To elucidate differences in fresh-leaf quality associated with cultivar and leaf tenderness at harvest, this study investigated three tea samples: Hainan Dayezhong with one bud and one leaf (1L-HN), Hainan Dayezhong with one bud and two leaves (2L-HN), and Yunnan Dayezhong with one bud and one leaf (1L-YN). Basic physicochemical indices, non-targeted metabolomics, and sensory evaluation were integrated for comprehensive analysis. The results showed that 1L-HN exhibited excellent sensory quality and contained abundant polyphenols and amino acids, thereby providing a material basis for its balanced taste profile. Metabolites such as L-tryptophan, 13(S)-HPOT, and linoleic acid were closely associated with the characteristic floral and fruity flavor of Hainan Dayezhong. Metabolomic analysis further indicated that flavonoid biosynthesis and glycerophospholipid metabolism were the major pathways contributing to the observed metabolic differences. This study provides a theoretical basis for understanding the mechanisms underlying flavor formation in different varieties of black tea.