Department of Pharmacy Services, Tuzluca Vocational High School, Igdir University, 76000, Igdir, Türkiye.
Chem Biodivers. 2022 Jul;19(7):e202200170. doi: 10.1002/cbdv.202200170. Epub 2022 Jun 8.
β-Glycosidases, which catalyse the hydrolysis of glycoside bonds, have a wide spectrum of industrial applications. However, the reaction product glucose inhibits the activities of many β-glucosidases. Consequently, the reduced catalytic activities of the enzyme limit the industrial applications of the enzymes. For that reason, the studies dealing with maintaining the activities of the relevant enzymes at high glucose concentrations are a great interest among the researchers. In this context, herein, protein-inorganic hybrid nanoflowers were synthesized using β-glucosidase and copper ion by fast sonication method for 10 min. After characterization of synthesized nanoflowers, pH/temperature studies, glucose tolerance, anti-protease activity, recyclability and total antioxidant and total oxidative capacity levels were estimated. Accordingly, the optimum pHs of free β-glucosidase and hybrid nanoflower (β-GNF) were found to be 6 and 5, respectively, and the optimum temperature values for both hybrid nanoflowers and free enzyme were 40 °C. β-GNF exhibited better activity than free enzyme in low acidic and alkaline environment and at high temperature. The nanoflower retained nearly all (99 %) of its initial activity at all glucose concentrations (0.01, 0.05 and 0.1 mg/mL), especially at pH 5 and 6. Also, β-GNF maintained more than 90 % of initial activity at 0.01 and 0.05 mg/mL glucose at pH 4 and 7. It also displayed about 96 % high residual activity after proteinase K treatment for 3 h at 37 °C, while that of the free β-glucosidase was about 87 %. The reusability studies showed that β-GNF only lost ∼28 % of its initial activities at the end of five cycles. The hybrid nanoflowers at 5 mg/mL concentration exhibited the high total antioxidant capacity. In addition, low total oxidant capacity and oxidative stress index levels were recorded at the same concentration of the hybrid nanoflower. The findings of the present study revealed that β-GNFs may be evaluated as a candidate for various industrial applications due to its high glucose tolerance, anti-protease activity, reusability and resistance to low acidic/alkaline environment and high temperature.
β-糖苷酶能够催化糖苷键的水解，具有广泛的工业应用。然而，反应产物葡萄糖会抑制许多β-葡萄糖苷酶的活性。因此，酶的催化活性降低限制了这些酶的工业应用。出于这个原因，研究人员对保持高葡萄糖浓度下相关酶的活性非常感兴趣。在这方面，本文通过快速超声法在 10 分钟内使用β-葡萄糖苷酶和铜离子合成了蛋白质-无机杂化纳米花。在对合成的纳米花进行表征后，评估了 pH/温度研究、葡萄糖耐受性、抗蛋白酶活性、可重复使用性以及总抗氧化和总氧化能力水平。因此，发现游离β-葡萄糖苷酶和杂化纳米花（β-GNF）的最佳 pH 值分别为 6 和 5，而游离酶和杂化纳米花的最佳温度值均为 40°C。在低酸性和碱性环境以及高温下，β-GNF 的活性均优于游离酶。在所有葡萄糖浓度（0.01、0.05 和 0.1mg/mL）下，纳米花都保留了近 100%的初始活性（99%），尤其是在 pH 值为 5 和 6 时。此外，在 pH 值为 4 和 7 时，在 0.01 和 0.05mg/mL 葡萄糖下，β-GNF 仍能保持初始活性的 90%以上。在 37°C 下用蛋白酶 K 处理 3 小时后，其仍保持约 96%的高残余活性，而游离β-葡萄糖苷酶的残余活性约为 87%。可重复使用性研究表明，β-GNF 在五个循环结束时仅损失了初始活性的约 28%。在 5mg/mL 浓度下，杂化纳米花表现出高总抗氧化能力。此外，在相同浓度的杂化纳米花下，记录到低总氧化剂能力和氧化应激指数水平。本研究的结果表明，由于其高葡萄糖耐受性、抗蛋白酶活性、可重复使用性以及对低酸性/碱性环境和高温的抵抗力，β-GNF 可以作为各种工业应用的候选物进行评估。
