Hossain Khondoker Moazzem, Khan Umama, Mahbubur Rahman S M, Khan Md Salauddin
Biotechnology and Genetic Engineering Discipline, Life Science School, Khulna University, Khulna-9208, Bangladesh.
Department of Genetic Engineering and Biotechnology, Faculty of Biological Science and Technology, Jashore University of Science and Technology (JUST), Jashore-7408, Bangladesh.
Biotechnol Rep (Amst). 2024 Sep 30;44:e00861. doi: 10.1016/j.btre.2024.e00861. eCollection 2024 Dec.
The hydrolytic enzyme, amylase possesses wide industrial applications and its production from bacterial sources by submerged fermentation is much simplified and economical. The research aimed to characterize amylase-producing bacteria and evaluate their potential for amylase activity regarding antimicrobial and fruit juice clarification. In current study, and was identified by 16S rRNA sequencing. After submerged fermentation, amylase activity of bacteria was measured by 3, 5-dinitro salicylic acid (DNS) assay. A substantial amount of amylase (423.47 mg/ml) in crude extract was measured by Bradford protein assay. Later, ammonium sulfate (80 %) precipitated partially purified amylase showed 1.6 times enhanced amylase activity (1484.94 U/ml) compared to crude amylase (973.23 U/ml). For highest amylase production, 72 h of optimum fermentation period was recorded at pH 7 with 2 % starch as substrate. Potent thermophilic amylase activity was observed at 65 °C In apple juice clarification activity of amylase, turbidity of juice was reduced to 54.18 %. Potential antimicrobial property of amylase was detected with largest zone of inhibition against ATCC 25922 (22.36 mm) and sp. ATCC 48559 (22.45 mm). Considering promising amylase properties, amylase-producing Bacillus strains from rice mill soil can be fermented for large scale amylase production providing application for industrial purposes including fruit juice clarification and antimicrobial activities. It will also overthrow the requirement of employing expensive and harmful chemicals in fruit juice clarification and combating pathogens.
水解酶淀粉酶具有广泛的工业应用，通过深层发酵从细菌来源生产淀粉酶要简单得多且经济实惠。该研究旨在鉴定产淀粉酶的细菌，并评估它们在淀粉酶活性方面在抗菌和果汁澄清方面的潜力。在当前研究中，通过16S rRNA测序鉴定了[具体菌种未给出]。深层发酵后，通过3,5-二硝基水杨酸（DNS）测定法测量细菌的淀粉酶活性。通过Bradford蛋白质测定法测定粗提物中大量的淀粉酶（423.47毫克/毫升）。后来，硫酸铵（80%）沉淀的部分纯化淀粉酶显示出比粗淀粉酶（973.23单位/毫升）高1.6倍的淀粉酶活性（1484.94单位/毫升）。为了获得最高的淀粉酶产量，在pH 7、以2%淀粉为底物的条件下，记录到最佳发酵期为72小时。在65℃观察到了强大的嗜热淀粉酶活性。在淀粉酶的苹果汁澄清活性方面，果汁的浊度降低到了54.18%。检测到淀粉酶具有潜在的抗菌特性，对金黄色葡萄球菌ATCC 25922（抑菌圈直径22.36毫米）和大肠杆菌ATCC 48559（抑菌圈直径22.45毫米）有最大的抑菌圈。考虑到淀粉酶具有良好的特性，来自碾米厂土壤的产淀粉酶芽孢杆菌菌株可以进行发酵以大规模生产淀粉酶，为包括果汁澄清和抗菌活性在内的工业用途提供应用。这也将摒弃在果汁澄清和对抗病原体方面使用昂贵且有害化学物质的需求。
