In this study, Ougan juice (OJ) and lactic acid bacteria fermented Ougan juice (FOJ) were investigated individually for their capability of preventing obesity in high-fat diet (HFD)-fed C57BL/6J mice. After being administered with OJ or FOJ for 10 weeks, the body weight gain, hyperlipidemia, and gut microbiota dysbiosis of HFD-fed mice were examined. The results showed that OJ or FOJ supplementation inhibited weight gain, lowered fat accumulation, reduced liver steatosis, improved glucose homeostasis and insulin sensitivity, increased brown adipose tissue (BAT) activity, and promoted white adipose tissue (WAT) browning. Both OJ and FOJ additions increased the diversity of gut microbiota. OJ reduced the relative abundance of phylum Erysipelatoclostridiaceae and genus Erysipelatoclostridium and remarkably increased SCFA-producing bacteria Blautia, while FOJ reduced the ratio of Firmicutes to Bacteroidetes and enhanced the relative abundance of family Lactobacillaceae. Spearman's correlation analysis revealed that Akkermansia, Dubosiella, and Muribaculaceae were significantly negatively correlated with obesity-related indexes. In general, FOJ exhibited a better inhibitory effect on obesity than OJ, and the possible inhibitory mechanism lies in promoting WAT browning and increasing intestinal probiotics. This study provides the guidance for developing fermented Ougan juice as an obesity-inhibiting functional food.

Grapefruit has attracted much attention as a functional fruit, of which “Cocktail” is a special variety with low acidity. The present study aimed to investigate the effects of alcoholic fermentation on the non-volatile and volatile compounds of “Cocktail” grapefruit juice. To analyze, a non-targeted metabolomics method based on UPLC-MS/MS and volatiles analysis using GC-IMS were performed. A total of 1015 phytochemicals were identified, including 296 flavonoids and 145 phenolic acids, with noticeably increasing varieties and abundance following the fermentation. Also 57 volatile compounds were detected, and alcoholic fermentation was effective in modulating aromatic profiles of grapefruit juice, with terpenes and ketones decreasing, and alcohols increasing together with esters. Citraconic acid and ethyl butanoate were the most variable non-volatile and volatile substances, respectively. The results provide a wealth of information for the study of “Cocktail” grapefruit and will serve as a valuable reference for the large-scale production of grapefruit fermented juice in the future.

This study examined the effects of phase II metabolism and efflux transportation on the bioavailability of naringin, hesperidin, and their aglycones (naringenin and hesperetin) in rats. Results indicated naringin and hesperidin have a lower oral bioavailability than their aglycones. Of all the phase II enzymes tested, UDP-glucuronosyltransferase (UGT) 1A1, UGT1A2, UGT1A3, UGT1A7 and SULT sulfotransferase (SULT) 1B1 were of minor importance regarding the phase II metabolism of naringenin and hesperetin in the small intestine. Naringin, hesperidin, and their aglycones were all extensively metabolised in the liver. Naringin and hesperidin were more extensively transported by efflux transporters compared to their aglycones. Significant correlations between phase II enzymes and efflux transporters were detected. In conclusion, more extensive metabolism of naringin and hesperidin than their aglycones in the small intestine, and the interplay of phase II enzymes and efflux transporters in the small intestine explain the lower relative oral bioavailability of naringin and hesperidin than their aglycones.

• Metabolomics technique uncovered 20 distinct anthocyanins in bayberry wine. • Distinct appearance in 'DK' and 'SJ' wines for variations in anthocyanin types. • Vitisin-like and malvidin-type anthocyanins firstly reported in bayberry wines. • A conspicuous decline in most glycosidic pigments in bayberry wine as maceration.

Poncirin (PC) and its aglycone, isosakuranetin (IR), occur naturally in citrus fruits. This study aimed to explore the pathways behind the different health benefits of PC and IR by evaluating the effect of these two bioactive flavonoids on the gut microbial diversity and metabolomics of mice. The 16S rRNA gene sequencing was used to analyze the alteration of gut microbiota in mice after PC and IR intervention. The metabolic impact of PC and IR in mice were studied using a metabolomics approach based on LC-MS analysis. Results showed that, after 7 days intervention, PC and IR multiplied the abundance of Parabacteroides in mice’s intestinal tracts by 1.2 and 1.0 times, respectively. PC increased the abundance of Bacteroides by 2.4 times. IR reduced the Allobaculum abundance by 1.0 time and increased Alloprevotella abundance by 1.5 times. When mice were given PC, their fecal acetic acid level increased by 1.8 times, while their isobutyric and isovaleric acid content increased by 1.2 and 1.3 times, respectively. Supplementation with IR had no significant effect on the content of short-chain fatty acids (SCFAs) in the feces of mice. The potential urine biomarkers of mice in the PC group were involved in the digestion and absorption of protein and carbohydrate, as well as the metabolism of amino acids, such as glycine, serine, threonine, tryptophan, D-arginine, D-ornithine, etc. IR mainly affected the amino acid metabolic pathways in mice, including taurine and hypotaurine metabolism, glutathione metabolism, histidine metabolism, D-glutamate metabolism, etc. This study provided valuable clues for future research on the health promoting mechanisms of PC and IR.