The possibility of associating starch degradation with bacterial beta-glucuronidase expression was examined. We proved that starving, in starch medium, amylase-negative Escherichia coli (M94) which has constitutive beta-glucuronidase greatly reduces (p < 0.01) its background activity, but the addition of both cell-free supernatants or cells of Bacillus subtilis (B10) producing amylase greatly increases (p < 0.01) the E. coli beta-glucuronidase activity. Increases in activity were maximal when amylase in the medium ranged from 0.3 to 0.8 U ml-1 and pH from 6.8 to 6.3, whereas higher amylase activity interacted with E. coli viability and the effect on beta-glucuronidase was less evident. The impact of B. subtilis amylase on E. coli beta-glucuronidase induction, observed when the organisms were co-cultured, indirectly supports the hypothesis that amylolytic activity of hindgut bacteria may be effective on beta-glucuronidase induction of the climax microflora. This last finding is important in the health field, considering the implication between the deconjugating role of this enzyme and consequent activation of toxic and carcinogenic compounds.
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Bioresour Technol
January 2025
Department of Biotechnology, Faculty of Biological Science and Technology, University of Isfahan, Isfahan 81746-73441, Iran; Environmental Research Institute, University of Isfahan, Isfahan 81746-73441, Iran.
Tannin-containing sorghum grains, suitable for acetone-butanol-ethanol (ABE) production by Clostridium acetobutylicum, have required pretreatment to eliminate tannins inhibiting the strain's amylolytic activity. This study investigates biobutanol production enhancement by immobilizing enzymes on polydopamine-functionalized polyethersulfone (PES) membranes with magnetic nanoparticles for Separated Hydrolysis and Fermentation (SHF) and Simultaneous Saccharification and Fermentation (SSF) processes. After multi-stage hot water treatment, TG3 sorghum (from the third stage) was used, where the enzyme-immobilized PES membrane produced 4.
View Article and Find Full Text PDFJ Agric Food Chem
January 2025
State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin 300457, China.
The amylolytic susceptibility of starch-lipid complexes with different forms of crystallites has been studied extensively, but the fermentation properties of these complexes remain little understood. Hence, the fecal fermentation properties of starch-lipid complexes with V-type and V-type crystallites were investigated in the present study. Compared to V-type complexes, fermentation of V-type complexes caused more severe disruption to the crystallites and resulted in greater acid, reducing sugar, and short-chain fatty acids (SCFAs) production.
View Article and Find Full Text PDFEnviron Monit Assess
October 2024
Papanin Institute for Biology of Inland Waters, Russian Academy of Sciences, Borok, Yaroslavl Oblast, Nekouzskii Raion, 152742, Russia.
Aquatic ecosystems are increasingly affected by anthropogenic pollution, including heavy metals like mercury, which accumulate in organisms and cause harmful effects. At the same time, human activities such as industrial operations and the use of electric power lines also alter the magnetic background in natural water bodies. However, the interaction between mercury exposure and magnetic fields remains poorly understood.
View Article and Find Full Text PDFJ Sci Food Agric
February 2025
Department of Biotechnology, Faculty of Technology Novi Sad, University of Novi Sad, Novi Sad, Serbia.
Background: To remain competitive, brewers must innovate by incorporating novel elements beyond traditional styles. Thus, exploring triticale as a modern substitute for barley malt is promising, especially given its higher amylolytic activity compared to barley. This study aimed to assess the impact of substituting up to 50% of barley malt with unmalted triticale on green beer quality, encompassing multiple stages from wort production to primary fermentation at a laboratory scale.
View Article and Find Full Text PDFJ Dairy Res
October 2024
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, P.R. China.
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