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Latilactobacillus (L.) sakei is a species of lactic acid bacteria (LAB) mostly studied according to its application in food fermentation. Previously, L. sakei L3 was isolated by our laboratory and possessed the capability of high exopolysaccharide (EPS) yield during sucrose-added fermentation. However, the understanding of sucrose promoting EPS production is still limited. Here, we analyzed the growth characteristics of L. sakei L3 and alterations of its transcriptional profiles during sucrose-added fermentation. The results showed that L. sakei L3 could survive between pH 4.0 and pH 9.0, tolerant to NaCl (<10%, w/v) and urea (<6%, w/v). Meanwhile, transcriptomic analysis showed that a total of 426 differentially expressed genes and eight non-coding RNAs were identified. Genes associated with sucrose metabolism were significantly induced, so L. sakei L3 increased the utilization of sucrose to produce EPS, while genes related to uridine monophosphate (UMP), fatty acids and folate synthetic pathways were significantly inhibited, indicating that L. sakei L3 decreased self-growth, substance and energy metabolism to satisfy EPS production. Overall, transcriptome analysis provided valuable insights into the mechanisms by which L. sakei L3 utilizes sucrose for EPS biosynthesis. The study provided a theoretical foundation for the further application of functional EPS in the food industry. [ABSTRACT FROM AUTHOR]

In this study, a Bacillus halotolerans (B. halotolerans) strain DT1 capable of producing exopolysaccharides (EPS) was isolated from dried cabbages of Tianjin, a local fermented vegetable product. Three distinct polysaccharide fractions were isolated from the fermentation broth of DT1, namely, DT1-0, DT1-2, and DT1-5. The structural composition and properties of these fractions were investigated. The predominant EPS, DT1-0, was identified as a novel heteropolysaccharide composed of fructose and glucose with branched structures. The repeating unit was determined to be [4)-α-D-Glcp-(1→6)-α-D-Glcp-(1→6)-β-D-Fruf-(2→6)-β-D-Fruf-(2→6-)-β-D-Fruf-(2→], with fructose and glucose connected by β-(2→1) and α-(1→4) glycosidic linkages between the third fructose and the first glucose, respectively. The molecular weight (Mw) was estimated to be 4.253 × 103 Da. DT1-0 presented a smooth and porous surface structure as observed through SEM and exhibited a water-holding capacity of 504 ± 5.3%, maximum thermal stability at 245 °C, and an oil-holding capacity of 387 ± 1.9% for coconut oil. DT1-2 was identified as a fructooligosaccharide. DT1-5 was characterized as a polysaccharide composed of glucose and fructose. In conclusion, these findings provide substantial support for the further application of B. subtilis strain DT1 and its EPS fractions, DT1-0, DT1-2, and DT1-5, as potential alternatives for functional food additives or ingredients. [ABSTRACT FROM AUTHOR]

The control of Aspergillus niger (A. niger) is of great significance for the agricultural economy and food safety. In this study, the antifungal effect and mechanism of iturin A from Bacillus amyloliquefaciens (CGMCC No. 8473) against A. niger (ATCC 16404) were investigated using biochemical analyses and proteomics. Changes in a mycelium treated with iturin A were observed using scanning electron microscopy and transmission electron microscopy, including mycelial twisting and collapse, organelle disintegration, and intracellular vacuolization. The cytomembrane integrity of A. niger was affected by iturin A, as detected by propidium iodide staining. In addition, the generation of excess reactive oxygen species, the hyperpolarization of the mitochondrial membrane potential and malondialdehyde accumulation also indicated that iturin A induced apoptosis in A. niger through the oxidative stress pathway. Proteomics results showed that 310 proteins were differentially expressed in the A. niger mycelium exposed to iturin A, including 159 upregulated proteins and 151 downregulated proteins, which were mainly associated with energy metabolism of A. niger. We propose that iturin A might inhibit the growth of A. niger by disrupting cytomembrane integrity, via oxidative stress, and by interfering with glycolysis/gluconeogenesis and the tricarboxylic acid cycle. Overall, iturin A is a promising antifungal agent that provides a rationale for controlling A. niger contamination in food. [ABSTRACT FROM AUTHOR]

Purpose: Potentially inappropriate prescribing (PIP) is commonly encountered in older adults; yet, there is limited information on the occurrence of PIP among older adults with hypertension. This study aims to determine and compare the prevalence of PIP and its association with comorbidities in older adult outpatients with hypertension across hospitals and community health centers (CHCs)., Methods: This 3-year (2015-2017) repeated cross-sectional study used electronic medical records from Shenzhen, China, involving 62 hospitals and 678 primary medical institutions. PIP was defined using the 2019 Beers Criteria. Older adults (≥65 years) with hypertension and at least one outpatient prescription were included. Modified Poisson regression analysis was used to assess the association between chronic comorbidities, healthcare settings, and PIP., Results: The prevalence of PIP in old adult outpatients with hypertension in 2015, 2016, and 2017 was 46.32%, 46.98%, and 46.58% in hospitals, with a sample size of 38,411, 46,235, and 50,495, respectively, and 29.14%, 26.66%, and 29.84% in CHCs, with a sample size of 26,876, 29,434, and 34,775 respectively. The top four most popular PIP in hospitals and CHCs was proton-pump inhibitors (PPIs), diuretics, benzodiazepines, and non-cyclooxygenase-selective non-steroidal anti-inflammatory drugs (NSAIDs), respectively. PIP was most associated with chronic gastrointestinal disease (adjusted prevalence ratio = 1.54, 95% confidence interval [CI] = 1.50-1.59) and mental and behavioral disorders (adjusted prevalence ratio = 1.49, 95% CI = 1.46-1.53) in hospitals and with mental and behavioral disorders (adjusted prevalence ratio = 1.99; 95% CI = 1.95-2.03) and musculoskeletal system and connective tissue disorders (adjusted prevalence ratio = 1.33; 95% CI = 1.31-1.36) in CHCs. The prevalence of PIP was significantly higher in hospital settings than in CHCs (adjusted prevalence ratio = 1.65; 95% CI = 1.63-1.66)., Conclusion: Among older adult outpatients with hypertension in Shenzhen, PIP was more prevalent in hospitals than in CHCs. The comorbidities most strongly associated with PIP were chronic gastrointestinal disease and mental and behavioral disorders in hospitals and mental and behavioral disorders in CHCs. Clinical pharmacy integration needs to be considered to reduce inappropriate prescribing in this vulnerable population., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Chen, Wang, Lu, Yang, Wang, Zheng, Zhou, Guo, Cai and Zhang.)