Utility of Functionalized Agarose Nanoparticles in Hydrolyzing Lactose in Batch Reactors for Dairy Industries

Abstract

The present study investigates the synthesis of agarose nanoparticles (ANPs) and its surface modification by galactose for the immobilization of β-galactosidase. Galactose modified ANPs retained 91% enzyme activity upon immobilization. Optimum pH (4.5) and temperature (50 °C) remains unchanged after immobilization. However, immobilized enzyme retained greater catalytic activity against lower and higher, pH and temperature ranges. Immobilized β-galactosidase retained 89% biocatalytic activity even at 4% galactose concentration as compared to enzyme in solution, and exhibited 81% activity even after seventh repeated uses. Immobilized enzyme hydrolyzed greater amount of lactose at higher temperatures as compared to β-galactosidase in solution, thereby suggesting its potential application in obtaining lactose-free dairy products at large scale.

Biotechnological Application of Surface Modified Cerium Oxide Nanoparticles

“…inhibitor binding site in β-galactosidase that promotes the reduction in inhibition as a result of the support to the inhibitor's access to the binding site (Kim et al, 2011;Ansari et al, 2018). Our study suggested that GCNPs-βG showed 71% activity even after 1 hour at 5% galactose concentration.…”

“…The free enzyme showed 56% activity at pH 6.0 while β-galactosidase immobilized on CNPs, carboxylated CNPs and glutaraldehyde-modified CNPs retained 69%, 75% and 84%, activity, respectively, under similar conditions. It could be due to greater alteration/ distortion produced in the tertiary structure of the free enzyme in highly acidic and basic solutions than that of the immobilized enzyme (Ansari et al, 2018). Figure 4 suggests that the temperature-optima was 50 o C for soluble and immobilized enzyme preparations.…”

“…The product formation obtained as a result of β-galactosidase hydrolysis was evaluated by continuously shaking an assay volume of 2.0 mL containing 1.79 mL of 0.1 M sodium acetate buffer (pH 4.5), 100 μL of suitably diluted enzyme and 0.2 mL of 2.0 M ONPG for 15 min at 40 o C. The reaction was terminated by adding 2.0 mL of 1.0 M sodium carbonate solution, and the product formed was spectrophotometrically analyzed and measured at 405 nm (Ansari et al, 2018).…”

“…Lactose solution (500 mL) was incubated with 250 U of soluble β-galactosidase and enzyme immobilized on the nanomatrices (CNPs, CCNPs and GCNPs) independently, and stirred continuously for 10 h at 50 o C in a shaking water bath. The sample aliquots were taken at various time intervals and subjected to the assay for the formation of glucose with the glucose oxidase-peroxidase assay kit (Ansari et al, 2018).…”

Preparation and Application in Drug Storage and Delivery of Agarose Nanoparticles

“…Wang and Wu [26] described the fabrication of agarose hydrogel nanoparticles using an emulsion-converted-to-suspension method and the application of the obtained particles for encapsulating proteins and peptides. Similar particles were used as batch reactors in dairy industry for the hydrolysis of lactose [27]. Furthermore, many works deal with the fabrication of hybrid metal-agarose particles for combining the electronic properties of metals and the biocompatibility of the agarose to obtain particles with application as biosensors [28,29].…”