A 1 percent dextrose broth using bromcresol green as a pH indicator is described for the presumptive identification of group B streptococci. The results in the medium are read after 24 hr incubation at 36C as a color change. This medium was tested using 550 strains of streptococci belonging to groups A, B, C, D, and G. All of the group A strains were negative whereas all of the group B and Group D strains were positive. Thus, by using bacitracin susceptibility, esculin hydrolysis, and BCG dextrose broth, the presumptive identification of the frequently encountered streptococci can be accomplished.
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J Pineal Res
March 2025
College of Enology, Shaanxi Provincial Key Laboratory of Viti-Viniculture, Shaanxi Engineering Research Center of Characteristic Fruit Directional Design and Machining, Northwest A&F University, Yangling, China.
Melatonin is involved in biological adverse stress response and enhances the ability of yeast to adapt to adverse conditions. This study investigated the mechanism of exogenous melatonin addition to Saccharomyces cerevisiae (S. cerevisiae) under copper stress.
View Article and Find Full Text PDFMar Drugs
January 2025
Section of Food and Nutrition, School of Agriculture and Food Science, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland.
A rise in antimicrobial resistance coupled with consumer preferences towards natural preservatives has resulted in increased research towards investigating antimicrobial compounds from natural sources such as macroalgae (seaweeds), which contain antioxidant, antimicrobial, and anticancer compounds. This study investigates the antimicrobial activity of compounds produced by the Irish seaweed against and , bacterial species which are relevant for food safety. Microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), ultrasound-microwave-assisted extraction (UMAE), and conventional extraction technologies (maceration) were applied to generate extracts from , followed by their preliminary chemical composition (total phenolic content, total protein content, total soluble sugars) and antimicrobial activity (with minimum inhibitory concentration determined by broth microdilution methods), examining also the molecular weight distribution (via high performance size exclusion chromatography) and oligosaccharide fraction composition (via high-performance liquid chromatography) of the polysaccharides, as they were the predominant compounds in these extracts, aiming to elucidate structure-function relationships.
View Article and Find Full Text PDFJ Fungi (Basel)
December 2024
Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, New Zealand.
Secondary metabolism is one of the main mechanisms uses to explore and colonize new niches, and 6-pentyl-α-pyrone (6-PP) is an important secondary metabolite in this process. This work focused on standardizing a method to investigate the production of 6-PP. Ethanol and ethyl acetate were both effective solvents for quantifying 6-PP in solution and had limited solubility in potato-dextrose-broth media.
View Article and Find Full Text PDFInt J Food Microbiol
February 2025
Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58, Rinkuourai-kita, Izumisano, Osaka 598-8531, Japan; Graduate School of Veterinary Science, Osaka Metropolitan University, Osaka, Japan; Asian Health Science Research Institute, Osaka Metropolitan University, Osaka, Japan; Osaka International Research Center for Infectious Diseases, Osaka Metropolitan University, 1-58, Rinkuourai-kita, Izumisano, Osaka 598-8531, Japan. Electronic address:
Since cefixime and tellurite are known to inhibit most bacteria belonging to Enterobacterales, we found that addition of tellurite inhibited E. albertii growth in Luria Bertani broth but not in tryptic soy broth (TSB), and addition of phosphate and soy peptone enhanced E. albertii growth in TSB in presence of tellurite.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Plant Genetic Engineering Laboratory, Department of Biotechnology, Bharathiar University, Coimbatore, 641046, Tamil Nadu, India. Electronic address:
Phanerochaete chrysosporium (Pc), is a prominent lignin-degrading fungus which serves as an important source for lignin-degrading enzymes (LDEs). The present study was focused on a detailed in silico analysis and gene expression patterns of lignin peroxidases (PcLiPs), which is a significant class of LDEs. In spite of extensive research on P.
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