GABA and fermented litchi juice enriched with GABA promote the beneficial effects in ameliorating obesity by regulating the gut microbiota in HFD-induced mice

Regulatory effects of lactic acid bacteria co-fermented Dendrocalamus latiflorus shoots on lipid-lowering functions and the gut microbiota in HFD-fed mice

This study employed Lactobacillus plantarum R1 and Lactobacillus brevis R2 to ferment Dendrocalamus latiflorus shoots, significantly enhancing γ-aminobutyric acid (GABA) content to 365.86 mg kg-1, representing a 3.86-fold increase compared to natural fermentation. Using fermented D. latiflorus shoots rich in GABA for intervention in HFD-induced obese mice, it was found that natural fermentation and inoculated fermentation reduced weight gain. Both treatments lowered serum TG, T-CHO, and LDL-C levels, reduced hepatic lipid accumulation and oxidative stress, and decreased liver IL-1β and TNF-α levels. Notably, inoculated fermentation had a more pronounced fat-reducing effect. In addition, fermented D. latiflorus shoots rich in GABA improved the diversity and abundance of the gut microbiota in mice and particularly increased the abundances of Bacteroides and Verrucomicrobia and reduced those of Firmicutes and Deferribacteres, thereby alleviating gut microbiota disorders in HFD-fed mice. These results indicated that probiotic fermentation significantly increased the GABA content in fermented D. latiflorus shoots, and the fermented D. latiflorus shoots rich in GABA played a role in lowering lipid levels and alleviating gut microbiota disorders in HFD-fed mice. This study provides a foundation for the comprehensive utilization and sustainable development of bamboo shoot resources.

From flavor to function: A review of fermented fruit drinks, their microbial profiles and health benefits

Fermented fruit drinks (FFDs) are gaining popularity among consumers for their unique flavors and potential health benefits. This review provides a systematic assessment of the flavor components in FFDs and explores the metabolic pathways for their formation. We examine the interactions between the structure of microbial communities and the development of these flavor components, highlighting the role of microorganisms in shaping the unique taste of FFDs. Additionally, we discuss the potential health benefits associated with FFDs, focusing on their relationship with microbial communities as supported by existing literature. The review also addresses future prospects and challenges in the field. Our findings indicate key fermenting microorganisms, such as lactic acid bacteria, yeast and acetic acid bacteria, are responsible for producing the distinctive flavor components in FFDs, including alcohols, ketones, aldehydes, esters, and fatty acids. These microorganisms also generate organic acids, amino acids, and carbohydrates, contributing to the drink's complex taste. Furthermore, this fermentation process enhances the bioactivity of FFDs, offering potential health benefits like antioxidant, anti-obesity, anti-diabetic, and anti-cancer properties. These insights are crucial for advancing fermentation technology and developing guidelines for producing nutrient-rich, flavorful FFDs.

Litchi pulp-derived gamma-aminobutyric acid (GABA) extract counteracts liver inflammation induced by litchi thaumatin-like protein

Gamma-aminobutyric acid (GABA) is the predominant amino acid in litchi pulp, known for its neuroregulatory effects and anti-inflammatory properties. Although previous research has highlighted the pro-inflammatory characteristics of litchi thaumatin-like protein (LcTLP), interplay between GABA and LcTLP in relation to inflammation remains unclear. This study aims to explore the hepatoprotective effects of the litchi pulp-derived GABA extract (LGE) against LcTLP-induced liver inflammation in mice and LO2 cells. In vivo experiments demonstrated that LGE significantly reduced the levels of aspartate transaminase and alanine transaminase, and protected the liver against infiltration of CD4+ and CD8+ T cells and histological injury induced by LcTLP. Pro-inflammatory cytokines including interleukin-6, interleukin-1β, and tumor necrosis factor-α were also diminished by LGE. The LGE appeared to modulate the mitogen-activated protein kinase (MAPK) signaling pathway to exert its anti-inflammatory effects, as evidenced by a reduction of 47%, 35%, and 31% in phosphorylated p38, JNK, and ERK expressions, respectively, in the liver of the high-dose LGE group. Additionally, LGE effectively improved the translocation of gut microbiota by modulating its microbiological composition and abundance. In vitro studies have shown that LGE effectively counteracts the increase in reactive oxygen species, calcium ions, and pro-inflammatory cytokines induced by LcTLP. These findings may offer new perspectives on the health benefits and safety of litchi consumption.

Probiotic-fermented tomato with hepatic lipid metabolism modulation effects: analysis of physicochemical properties, bioactivities, and potential bioactive compounds

Lactiplantibacillus plantarum NCUH001046 (LP)-fermented tomatoes exhibited the potential to alleviate obesity in our previous study. This subsequent study further delves deeper into the effects of LP fermentation on the physicochemical properties, bioactivities, and hepatic lipid metabolism modulation of tomatoes, as well as the analysis of potential bioactive compounds exerting obesity-alleviating effects. Results showed that after LP fermentation, viable bacterial counts peaked at 9.11 log CFU mL-1 and sugar decreased, while organic acids, umami amino acids, total phenols, and total flavonoids increased. LP fermentation also improved the inhibition capacities of three digestive enzyme activities and Enterobacter cloacae growth, as well as antioxidant activities. Western blot results indicated that fermented tomatoes, especially live probiotic-fermented tomatoes (LFT), showed improved effects compared to unfermented tomatoes in reducing hepatic lipid accumulation by activating the AMPK signal pathway. UHPLC-Q-TOF/MS-based untargeted metabolomics analysis showed that chlorogenic acid, capsiate, tiliroside, irisflorentin, and homoeriodictyol levels increased after fermentation. Subsequent cell culture assays demonstrated that irisflorentin and homoeriodictyol reduced lipid accumulation via enhancing AMPK expression in oleic acid-induced hyperlipidemic HepG2 cells. Furthermore, Spearman's correlation analysis indicated that the five phenols were positively associated with hepatic AMPK pathway activation. Consequently, it could be inferred that the five phenols may be potential bioactive compounds in LFT to alleviate obesity and lipid metabolism disorders. In summary, these findings underscored the transformative potential of LP fermentation in enhancing the bioactive profile of tomatoes and augmenting its capacity to alleviate obesity and lipid metabolism disorders. This study furnished theoretical underpinnings for the functional investigation of probiotic-fermented plant-based foods.

Synergistic anti-infectious bronchitis virus activity of Phillygenin combined Baicalin by modulating respiratory microbiota and improving metabolic disorders

Phillygenin (PHI) and Baicalin (Bai) are the major chemical ingredients extracted from Forsythia suspensa and Scutellaria baicalensis, respectively. The mixture of Forsythia suspensa and Scutellaria baicalensis according to the theories of Traditional Chinese Veterinary Medicine, compounded formulation can effectively exert heat-clearing and detoxifying effect, but the synergistic anti-IBV activity of PHI combined with Bai was unclear. Here, the protection of PHI combined with Bai on avian infectious bronchitis virus (IBV) M41 infection and the change of respiratory microbiota and metabolomics profiles in broilers that infected with IBV were investigated. According to the experimental findings, the combination of PHI and Bai effectively alleviated broilers' slowing-growth weight and respiratory symptoms. This was accompanied by a reduction in viral copies and histopathological changes, as well as an increase of antiviral protein (G3BP1) level in tracheas and anti-IBV antibody levels in serum. In addition, 16s RNA sequencing revealed that IBV infection significantly changed respiratory microbiota composition at different taxonomic levels and respiratory metabolism composition in broilers. Interestingly, PHI combined with Bai modulated the composition of respiratory microfloras, especially the abundance of Firmicutes and Lactobacillaceae were upregulated, as well as the abundance of Proteobacteria was downregulated. The metabolomics results indicated that PHI combined with Bai involved in glucose, lipids, amino acids and nucleotide metabolism during IBV infection. In summary, PHI combined with Bai exhibited a synergistic effect on preventing infectious bronchitis (IB), with the protection being closely associated with the composition of respiratory microbiota and metabolites. Therefore, adding the mixture of PHI and Bai to the chicken drinking water is recommended to prevent and control IB in clinical.