Effects of Three Kinds of Carbohydrate Pharmaceutical Excipients-Fructose, Lactose and Arabic Gum on Intestinal Absorption of Gastrodin through Glucose Transport Pathway in Rats.

BACKGROUND: Some glucoside drugs can be transported via intestinal glucose transporters (IGTs), and the presence of carbohydrate excipients in pharmaceutical formulations may influence the absorption of them. This study, using gastrodin as probe drug, aimed to explore the effects of fructose, lactose, and arabic gum on intestinal drug absorption mediated by the glucose transport pathway. METHODS: The influence of fructose, lactose, and arabic gum on gastrodin absorption was assessed via pharmacokinetic experiments and single-pass intestinal perfusion. The expression of sodium-dependent glucose transporter 1 (SGLT1) and sodium-independent glucose transporter 2 (GLUT2) was quantified via RT‒qPCR and western blotting. Alterations in rat intestinal permeability were evaluated through H&E staining, RT‒qPCR, and immunohistochemistry. RESULTS: Fructose reduced the area under the curve (AUC) and peak concentration (Cmax) of gastrodin by 42.7% and 63.71%, respectively (P < 0.05), and decreased the effective permeability coefficient (Peff) in the duodenum and jejunum by 58.1% and 49.2%, respectively (P < 0.05). SGLT1 and GLUT2 expression and intestinal permeability remained unchanged. Lactose enhanced the AUC and Cmax of gastrodin by 31.5% and 65.8%, respectively (P < 0.05), and increased the Peff in the duodenum and jejunum by 33.7% and 26.1%, respectively (P < 0.05). SGLT1 and GLUT2 levels did not significantly differ, intestinal permeability increased. Arabic gum had no notable effect on pharmacokinetic parameters, SGLT1 or GLUT2 expression, or intestinal permeability. CONCLUSION: Fructose, lactose, and arabic gum differentially affect intestinal drug absorption through the glucose transport pathway. Fructose competitively inhibited drug absorption, while lactose may enhance absorption by increasing intestinal permeability. Arabic gum had no significant influence.

Breeding of high-tolerance yeast by adaptive evolution and high-gravity brewing of mutant.

BACKGROUND: Ethanol and osmotic stresses are the major limiting factors for brewing strong beer with high-gravity wort. Breeding of yeast strains with high osmotic and ethanol tolerance and studying very-high-gravity (VHG) brewing technology is of great significance for brewing strong beer. RESULTS: This study used an optimized microbial microdroplet culture (MMC) system for adaptive laboratory evolution (ALE) of Saccharomyces cerevisiae YN81 to improve its tolerance to osmotic and ethanol stress. Meanwhile, we investigated the VHG and VHG with added ethanol (VHGAE) brewing processes for the evolved mutants in brewing strong beer. The results showed that three evolved mutants were obtained; among them, the growth performance of YN81mc-8.3 under 300, 340, 380, 420 and 460 g L-1 sucrose stresses was greater than that of the other strains. The ethanol tolerance of YN81mc-8.3 was 12%, which was 20% higher than that of YN81. During strong-beer brewing in a 100 L cylindrical cone-bottom tank, the sugar utilization and ethanol yield of YN81mc-8.3 outperformed those of YN81 in both the VHG and VHGAE brewing processes. Measurement of the diacetyl concentration showed that YN81mc-8.3 had a stronger diacetyl reduction ability; in particular, the real degree of fermentation of beers brewed by YN81mc-8.3 in VHG and VHGAE brewing processes was 75.35% and 66.71%, respectively - higher than those of the two samples brewed by YN81. Meanwhile, the visual, olfactive and gustative properties of the strong beer produced by YN81mc-8.3 were better than those of the other beers. CONCLUSION: In this study, the mutant YN81mc-8.3 and the VHGAE brewing process were optimal and represented a better alternative strong-beer brewing process. © 2023 Society of Chemical Industry.

Quorum sensing: cell-to-cell communication in Saccharomyces cerevisiae.

Quorum sensing (QS) is one of the most well-studied cell-to-cell communication mechanisms in microorganisms. This intercellular communication process in Saccharomyces cerevisiae began to attract more and more attention for researchers since 2006, and phenylethanol, tryptophol, and tyrosol have been proven to be the main quorum sensing molecules (QSMs) of S. cerevisiae. In this paper, the research history and hotspots of QS in S. cerevisiae are reviewed, in particular, the QS system of S. cerevisiae is introduced from the aspects of regulation mechanism of QSMs synthesis, influencing factors of QSMs production, and response mechanism of QSMs. Finally, the employment of QS in adaptation to stress, fermentation products increasing, and food preservation in S. cerevisiae was reviewed. This review will be useful for investigating the microbial interactions of S. cerevisiae, will be helpful for the fermentation process in which yeast participates, and will provide an important reference for future research on S. cerevisiae QS.

Screening and transcriptomic analysis of the ethanol-tolerant mutant Saccharomyces cerevisiae YN81 for high-gravity brewing.

Ethanol stress is one of the major limiting factors for high-gravity brewing. Breeding of yeast strain with high ethanol tolerance, and revealing the ethanol tolerance mechanism of Saccharomyces cerevisiae is of great significance to the production of high-gravity beer. In this study, the mutant YN81 was obtained by ultraviolet-diethyl sulfate (UV-DES) cooperative mutagenesis from parental strain CS31 used in high-gravity craft beer brewing. The ethanol tolerance experiment results showed that cell growth and viability of YN81 were significantly greater than that of CS31 under ethanol stress. The ethanol tolerance mechanisms of YN81 were studied through observation of cell morphology, intracellular trehalose content, and transcriptomic analysis. Results from scanning electron microscope (SEM) showed alcohol toxicity caused significant changes in the cell morphology of CS31, while the cell morphology of YN81 changed slightly, indicating the cell morphology of CS31 got worse (the formation of hole and cell wrinkle). In addition, compared with ethanol-free stress, the trehalose content of YN81 and CS31 increased dramatically under ethanol stress, but there was no significant difference between YN81 and CS31, whether with or without ethanol stress. GO functional annotation analysis showed that under alcohol stress, the number of membrane-associated genes in YN81 was higher than that without alcohol stress, as well as CS31, while membrane-associated genes in YN81 were expressed more than CS31 under alcohol stress. KEGG functional enrichment analysis showed unsaturated fatty acid synthesis pathways and amino acid metabolic pathways were involved in ethanol tolerance of YN81. The mutant YN81 and its ethanol tolerance mechanism provide an optimal strain and theoretical basis for high-gravity craft beer brewing.