Biotechnological potential of microbial α-galactosidases

Abstract

The enzyme α-galactosidase (α-D-galactoside galactohydrolase; EC 3.2.1.22) catalyzes the hydrolysis of α-1,6-linked galactose residues in oligosaccharides and polymeric galactomannan. The α-galactosidases are of particular interest in view of their many potential biotechnological and medical applications. These enzymes have found wide use in various industries such as food and feed, sugar and paper and pulp for the removal of raffinose and stachyose. They are also important medically for blood group conversion and in the treatment of Fabry disease. Most of the research on α-galactosidases has focused on their isolation from various microbial sources. In the last decade, cloning of novel α-galactosidase genes and their heterologous expression has gained momentum. The present review focuses on the production of α-galactosidases from bacteria, fungi and yeast, and discusses their properties. Recent progress on cloning and heterologous expression in various hosts is summarized with special emphasis on their application in various fields.

Enhanced elimination of non‐digestible oligosaccharides from soy milk by immobilized α‐galactosidase: A comparative analysis

“…These results indicate that the immobilized enzyme can be recovered and reused, which can effectively reduce the operational cost of enzyme applications. The operational stability or reusability of the immobilized α‐galactosidase in this study was found to be better than few other immobilized α‐galactosidases reported earlier (Katrolia et al, ). Storage stability of an enzyme is an important parameter to assess its long‐term usage in the industry.…”

“…Removal of oligosaccharides from soy milk is, therefore, a major factor which can improve its consumer acceptability and popularity. The enzyme, α‐galactosidase catalyzes the hydrolysis of 1,6‐linked‐α‐galactose residues from raffinose, stachyose, and melibiose and hence is of great importance in the food and feed industries (Jang et al, ; Katrolia, Rajashekhara, Yan, & Jiang, ; Ye et al, ). α‐Galactosidases have applications in the food industry for removal of RFOs from various legumes and beans; in the beet‐sugar industry for removal of raffinose from beet sugar; and in the feed industry for improving the nutritional value of animal feed (Boopathy, Gupta, & Ramudu, ; Moon et al, ; Zhou et al, ).…”

“…In the recent years, researchers have immobilized α‐galactosidases using different matrices (Baffa Júnior, Viana, de Rezende, Soares, & Guimarães, ; Bayraktar, Serilmez, Karkaş, Çelem, & Önal, ; Lee, Park, & Cho, ; Okutucu, Çelem, & Önal, ; Singh et al, ). For feasibility of industrial applications, many factors have to be considered while choosing suitable immobilization matrix such as ease of immobilization, non‐toxicity for use in food industry and cost‐effectiveness (Katrolia et al, ; Nath et al, ). Furthermore, it is desirable that the immobilized enzyme exhibits better biochemical properties like catalytic efficiency, stability, and shelf life compared to the free enzyme.…”

High-level expression of a novel α-galactosidase gene from Rhizomucor miehei in Pichia pastoris and characterization of the recombinant enyzme

“…Usually, fugal a-galactosidases are optimally active within the acidic pH range (4.5-5.5) [2,27]. Despite its acid pH optimum (pH 5.5), RmgalB retained more than 90% of its activity within a broad pH range from 5.5 to 9.5, and even retained over 60% of the activity at pH 4.0 for 30 min.…”

“…They have many potential applications in industries [2]. a-Galactosidases are employed in the sugar industry to enhance sugar recovery by eliminating raffinose from sugar beet syrup.…”