Revealing the effects of Moringa oleifera Lam. leaves addition on Fuzhuan Brick Tea by metabolomic and microbiota analysis

Amelioration of Obesity-Related Disorders in High-Fat Diet-Fed C57BL/6 Mice Following Fecal Microbiota Transplantation From DL-Norvaline-Dosed Mice

Fecal microbiota transplantation (FMT) could significantly alter the recipient's gut bacteria composition and attenuate obesity and obesity-related metabolic syndromes. DL-norvaline is a nonproteinogenic amino acid and possesses anti-obesity potential. However, the specific mechanisms by which gut microbiota might mediate beneficial effects of DL-norvaline have not been completely elucidated. In this study, DL-norvaline-mediated FMT upregulated the beneficial bacteria (Clostridia_UCG_014, Christensenellales, Bacilli, Ileibacterium, Dubosiella, Lactobacillus, Muribaculaceae, and Bacteroidaceae) and downregulated the harmful bacteria (Tuzzerella and Marinifilaceae), further intestinal inflammation, oxidative stress, and intestinal barrier were alleviated as well as short chain fatty acids levels were increased, thus alleviating glucose and insulin metabolism, improving biochemical indexes and energy metabolism and decreasing body weight gain and tissue weight. However, heat-inactivated FMT did not demonstrate any of those improvements in obese mice. Notably, both DL-norvaline-mediated FMT and heat-inactivated FMT increased Bacteroidaceae and Muribaculaceae, this being a signature of alterations to the gut microbiota marker caused by DL-norvaline. Therefore, the beneficial effects of DL-norvaline were transmissible via FMT. This study highlighted the pivotal involvement of the gut microbiota in the development of obesity and provided a novel insight into the underlying mechanisms of FMT, thereby potentially enhancing the efficacy and refinement of FMT utilization.

Comprehensive Analysis of Fecal Microbiome and Metabolomics Uncovered dl-Norvaline-Ameliorated Obesity-Associated Disorders in High-Fat Diet-Fed Obese Mice by Targeting the Gut Microbiota

Norvaline is a nonproteinogenic amino acid and an important food ingredient supplement for healthy food. In this study, dl-norvaline administration reduced body weight by more than 40% and improved glucose metabolism and energy metabolism in obese mice induced by a high-fat diet (HFD). Combination analysis of microbiome and metabolomics showed that dl-norvaline supplementation regulated gut bacteria structure, such as increasing beneficial bacteria (Mollicutes_RF39, Ruminococcaceae, Bacteroidaceae, Rikenellaceae, Lactobacillaceae, Clostridiaceae_1, uncultured_bacterium_f_Muribaculaceae, and Rikenellaceae_RC9_gut_group) and decreasing harmful bacteria (Fusobacteriia, Desulfovibrionales, Enterobacteriaceae, Burkholderiaceae, Helicobacteraceae, and Veillonellaceae) and modulated the metabolites involved in arachidonic acid metabolism, thus further promoting short-chain fatty acid production and improving gut barrier, thereby inflammatory responses and oxidative stress were ameliorated. In addition, the pseudogerm-free mouse model verified that dl-norvaline ameliorated obesity-associated disorders in HFD-fed obese mice by targeting gut microbiota. These results clarified that dl-norvaline may be promising for developing and innovating potential functional food products.

Metabolomics analysis of flavor differences in Shuixian (Camellia sinensis) tea from different production regions and their microbial associations

Shuixian is renowned for its "rock flavor". However, the variations in Shuixian flavor are unclear, as the discussion mainly considers regional factors and overlooks the role of microorganisms. Sensory evaluation of Shuixian from three different regions (Zhengyan, Banyan, and Waishan) revealed that each had unique flavor characteristics: a woody aroma with slight acidity, a strong floral and fruity aroma with good freshness, and a distinct sweet aroma and sourness. Metabolomic analyses have revealed that 2-methylpyrazine was a crucial component of the woody aroma, whereas other metabolites contributed to sweet aroma, freshness, and acidity. Moreover, examinations of the relationship between flavor metabolites and microorganisms revealed that fungi had a more pronounced influence on the metabolite content of Shuixian. The study evaluated the role of fermentation microorganisms in shaping the flavor based on Shuixian flavor analyses, contributing to further research into the "rock flavor", as well as potential microbial interventions.

Identification of phenolic compounds from fermented Moringa oleifera Lam. leaf supplemented with Fuzhuan brick tea and their volatile composition and anti-obesity activity

As a nutritious plant with valuable potential, the Moringa oleifera Lam. (MOL) leaf addition on Fuzhuan brick tea (FBT) for the co-fermentation (MOL-FBT) was an industry innovation and a new route to make full use of MOL leaf. After optimization of the extraction conditions, the best conditions for the polyphenols extraction method from MOL-FBT (MFP) were 60°C for 40 min (1:80, V/W) using response surface methodology. A total of 30 phenolics were identified and quantified. Most of the polyphenols were increased after adding MOL leaf for co-fermentation compared to FBT polyphenols. In particular, caffeic acids were found only in MFP. Moreover, the MFP received high value in taste, aroma, and color. In total, 62 volatile flavor compounds, consisting of 3 acids, 5 alcohols, 15 aldehydes, 4 esters, 20 hydrocarbons, 10 ketones, and 5 others, were identified in MFP. In addition, MFP inhibited 3T3-L1 preadipocyte differentiation in a dose-dependent manner and decreased lipid accumulation via the peroxisome proliferator-activated receptor gamma (PPARγ)/CCAAT/enhancer binding protein alpha (CEBPα)/cluster of differentiation 36 (CD36) axis and induced a brown adipocyte-like phenotype. In vivo experiments were further conducted to confirm the in vitro results. MFP regulated lipid accumulation, glucose/insulin tolerance, improved liver and kidney function, and inhibited the secretion of pro-inflammatory factors by the PPARγ/CEBPα/CD36 axis and alleviated inflammation in high fat and high fructose diet-induced obese mice. In summary, MFP possesses high-quality properties and anti-obesity effects, as well as the great potential to be used as a novel functional food product.

Uncovering the effect of Moringa oleifera Lam. leaf addition to Fuzhuan Brick Tea on sensory properties, volatile profiles and anti-obesity activity

As a nutritious plant with valuable potential, the Moringa oleifera Lam. leaf addition to Fuzhuan Brick Tea (FBT) for co-fermentation is an industrial innovation and a new route to make full use of Moringa oleifera Lam. leaves. However, the sensory properties, volatile profiles and anti-obesity activity of Fuzhuan Brick (Moringa oleifera Lam.) tea (MFBT) are still unknown. The results demonstrated that MFBT has richer and more complex smell and taste, better color and higher overall acceptance scores. In total, 57 volatile flavor compounds, consisting of 3 acids, 16 hydrocarbons, 5 esters, 8 ketones, 13 aldehydes, 6 alcohols and others, were identified using HS-SPME-GC-MS. The characteristic odor components in MFBT were 3-buten-2-one, 4-(2,6,6-trimethyl-1-cyclohexen-1-yl)- and 1-cyclohexene-1-carboxaldehyde, 2,6,6-trimethyl-, which gave it a floral, woody, sweet, herbal and fruity aroma. 2-Octenal, (E) contributed significantly to the aroma of FBT, which could impart fresh, fatty and green aromas. In addition, MFBT could better regulate lipid accumulation, glucose tolerance, insulin tolerance and inflammation response more effectively than FBT. The mechanism is that MFBT could better regulate the dysbiosis of gut microbiota induced by HFFD, mainly increasing the abundance of beneficial bacteria such as SCFA-producing bacteria (Bacteroidetes, Lactobacillaceae, Bacteroidales_S24-7_group and Clostridiaceae_1) and decreasing the abundance of harmful bacteria such as pro-inflammatory/obesity and metabolic syndrome-related bacteria (Proteobacteria, Deferribacteres, Desulfovibrio, Catenibacterium and Helicobacter), which in turn increased feces short-chain fatty acids and lowered circulating lipopolysaccharides. These results suggested that co-fermentation with Moringa oleifera Lam. leaf could significantly improve the quality and enhance the anti-obesity effect of FBT.