Improvement of catalytic properties of starch hydrolyzing fungal amyloglucosidase: Utilization of agar-agar as an organic matrix for immobilization. (1st December 2019)

• Record Type: Journal Article
• Authors: Pervez, Sidra; Nawaz, Muhammad Asif; Jamal, Muhsin; Jan, Tour; Maqbool, Farhana; Shah, Ismail; Aman, Afsheen; Ul Qader, Shah Ali
• Is Part Of: Carbohydrate research. Volume 486(2019)
• Publication Date: 2019-12-01
• Subjects: Agar-agar -- Entrapment -- Immobilization -- Reusability -- Starch hydrolysis -- Bioprocessing; Carbohydrates -- Periodicals; Chemistry, Organic -- Periodicals; Biochemistry -- Periodicals; Carbohydrates -- Periodicals; Chimie organique -- Périodiques; Glucides -- Périodiques; Biochemistry; Carbohydrates; Chemistry, Organic; Periodicals; Electronic journals; 507.78
• DOI: 10.1016/j.carres.2019.107860
• Languages: English
• ISSNs: 0008-6215

Abstract

Abstract: In this study, amyloglucosidase was immobilized within agar-agar through entrapment technique for the hydrolysis of soluble starch. Enzymatic activities of soluble and entrapped amyloglucosidase were compared using soluble starch as a substrate. Partially purified enzyme was immobilized and maximum immobilization yield (80%) was attained at 40 gL -1 of agar-agar. Enzyme catalysis reaction time shifted from 5.0 min to 10 min after immobilization. Similarly, a five-degree shift in temperature (60 °C–65 °C) and a 0.5 unit increase in pH (pH-5.0 to pH-5.5) were also observed. Substrate saturation kinetics revealed that K m of entrapped amyloglucosidase increased from 1.41 mg ml −1 (soluble enzyme) to 3.39 mg ml −1 (immobilized enzyme) whereas, V max decreased from 947 kU mg −1 (soluble enzyme) to 698 kU mg −1 (immobilized enzyme). Entrapped amyloglucosidase also exhibited significant catalytic performance during thermal and storage stability when compared with soluble enzyme. Reusability of entrapped amyloglucosidase for hydrolysis of soluble starch demonstrated its recycling efficiency up to six cycles which is an exceptional characteristic for continuous bioprocessing of soluble starch into glucose. Graphical abstract: Image 1 Highlights: Maltase was immobilized within Agar-agar matrix support via entrapment technique. Surface morphology of entrapped enzyme was analyzed by Scanning electron microscopy. Maximum immobilization yield was achieved with 4.0% agar-agar concentration. Optimum pH and temperature of entrapped maltase was found to be 7.0 and 65 °C, respectively. The thermal, storage stability and recycling efficiency of free maltase were improved after immobilization.