کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
69997 48805 2013 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Characterization of a glucose- and solvent-tolerant extracellular tannase from Aspergillus phoenicis
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Characterization of a glucose- and solvent-tolerant extracellular tannase from Aspergillus phoenicis
چکیده انگلیسی

Tannases have attracted wider attention because of their biotechnological potential, especially enzymes from filamentous fungi and other microorganisms. However, the biodiversity of these microorganisms has been poorly explored, and few strains were identified for tannase production and characterization. This article describes the production, purification and characterization of a glucose- and solvent-tolerant extracellular tannase from Aspergillus phoenicis. High enzymatic levels were obtained in Khanna medium containing tannic acid up to 72 h at 30 °C under 100 rpm. The purified enzyme with 65% of carbohydrate content had an apparent native molecular mass of 218 kDa with subunits of 120 kDa and 93 kDa and was stable at 50 °C for 1 h. Optima of temperature and pH were 60 °C and 5.0–6.5, respectively. The enzyme was not affected significantly by most ions, detergents and organic solvents. While glucose did not affect the tannase activity, the addition of a high concentration of gallic acid did. The Km values were 1.7 mM (tannic acid), 14.3 mM (methyl-gallate) and 0.6 mM (propyl-gallate). The enzyme was able to catalyze the transesterification reaction to produce propyl-gallate. All biochemical properties suggest the biotechnological potential of the glucose- and solvent-tolerant tannase from A. phoenicis.

Figure optionsDownload as PowerPoint slideHighlights
► The tannase produced by A. phoenicis is a heterodimeric glycoprotein.
► The enzyme was tolerant to glucose and organic solvents.
► Tannic acid, methyl gallate and propyl gallate were hydrolyzed for the enzyme.
► The enzyme was able to catalyze transesterification to produce propyl-gallate.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Catalysis B: Enzymatic - Volumes 85–86, January 2013, Pages 126–133
نویسندگان
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