An endo-polygalacturonase secreted by Aspergillus sojae was characterized after being purified to homogeneity from submerged cultures with orange peel as the sole carbon source by gel filtration and ion-exchange chromatographies. According to SDS-PAGE and analytical isoelectric focusing analyses, the enzyme presents a molecular weight of 47 kDa and pI value of 4.2. This enzyme exhibits considerable stability under highly acidic to neutral conditions (pH 1.5-6.5) and presents a half-life of 2 h at 50°C. Besides its activity towards pectin and polygalacturonic acid, the enzyme displays pectin-releasing activity, acting best in a pH range of 3.3-5.0. Thin-layer chromatographic analysis revealed that tri-galacturonate is the main enzymatic end product of polygalacturonic acid hydrolysis, indicating that it is an endo-polygalacturonase. The enzyme exhibits Michaelis-Menten kinetics, with KM and VMAX values of 0.134 mg/mL and 9.6 µmol/mg/min, respectively, and remained stable and active in the presence of SO2, ethanol, and various cations assayed except Hg2+.
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http://dx.doi.org/10.1159/000460296 | DOI Listing |
Enzyme Microb Technol
January 2025
Protein Chemistry and Enzyme Technology, Department of Biotechnology and Biomedicine, Building 221, Technical University of Denmark, Lyngby DK-2800 Kgs, Denmark. Electronic address:
Aspergillus spp. and Rhizopus spp., used in solid-state plant food fermentations, encode cobalamin-independent methionine synthase activity (MetE, EC 2.
View Article and Find Full Text PDFJ Agric Food Chem
December 2024
U.S. Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, New Orleans, Louisiana 70124, United States.
Legumes are a predominant source of isoflavones, termed phytoestrogens, that mimic 17β-estradiol (E2). Phytoalexins are inducible isoflavones produced in plants subjected to environmental stressors (e.g.
View Article and Find Full Text PDFFoods
November 2024
Southern Regional Research Center, Agricultural Research Service, U. S. Department of Agriculture, New Orleans, LA 70124, USA.
Legumes are a rich source of polyphenolic compounds known for their ability to promote health. Under stress conditions, legumes have been shown to produce higher levels of secondary metabolites, as a defensive mechanism. Hence, the present study aimed to induce legume seeds (e.
View Article and Find Full Text PDFHeliyon
August 2024
Department of Horticulture and Life Science, Yeungnam University, Republic of Korea.
J Food Sci
September 2024
Université de Rennes, Inserm, EHESP, Irset (Institut de Recherche en Santé, Environnement et Travail)-UMR_S 1085, Rennes, France.
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