School of Life Science, Shanxi University, Taiyuan, China.
Department of Food Science and Agricultural Chemistry, Macdonald Campus, McGill University, Ste-Anne-de-Bellevue, Québec, Canada.
J Food Biochem. 2019 Feb;43(2):e12713. doi: 10.1111/jfbc.12713. Epub 2018 Nov 8.
A chitinase was purified from naked oat (Avena chinensis) seeds using simple chromatographic techniques. Its molecular weight and isoelectric point were determined as 35 kDa and 8.9, respectively. The purified chitinase exhibited specific activity of 3.6 U/mg and 15.6% yield using colloidal chitin as substrate. Partial amino acid sequence analysis and homology search indicated that it probably belonged to Class I plant chitinase, glycosyl hydrolase family 19. With chitin as substrate, the optimum pH and temperature of the chitinase were pH 7.0 and 40°C, respectively. The chitinase was remarkably stable from 30°C up to 50°C, but was inactivated at high temperatures above 85°C. Antifungal activity in vitro tests demonstrated this purified chitinase had potent, dose-dependent inhibitory activity against the fungi Panus conchatus and Trichoderma reesei. PRACTICAL APPLICATIONS: Chitinase has broad applications in many fields including the food industry and is recognized as one of the antifungal substances with potential use in plant disease resistance or biological control in agriculture. This study developed cost-effective purification methods for producing chitinase from naked oat (Avena chinensis) seeds, which may favor large-scale production of the enzyme. The remarkable stability of the chitinase at moderate temperatures (30°C-50°C), makes it a potentially useful enzyme in bioprocessing to produce chitooligosaccharides for various applications in the food, health, and agriculture sectors.
从裸燕麦（Avena chinensis）种子中使用简单的色谱技术纯化了一种几丁质酶。其分子量和等电点分别确定为 35 kDa 和 8.9。以胶体几丁质为底物时，纯化的几丁质酶表现出 3.6 U/mg 的比活和 15.6%的产率。部分氨基酸序列分析和同源性搜索表明，它可能属于 I 类植物几丁质酶，糖苷水解酶家族 19。以几丁质为底物时，几丁质酶的最适 pH 和温度分别为 pH 7.0 和 40°C。该几丁质酶在 30°C 至 50°C 之间非常稳定，但在 85°C 以上的高温下失活。体外抗真菌活性测试表明，这种纯化的几丁质酶对真菌 Panus conchatus 和 Trichoderma reesei 具有强大的、剂量依赖性的抑制活性。实际应用：几丁质酶在许多领域具有广泛的应用，包括食品工业，被认为是具有潜在用途的抗真菌物质之一，可用于植物抗病或农业生物防治。本研究开发了从裸燕麦（Avena chinensis）种子中生产几丁质酶的具有成本效益的纯化方法，这可能有利于该酶的大规模生产。几丁质酶在中等温度（30°C-50°C）下的显著稳定性，使其成为生物加工生产用于食品、健康和农业领域的各种应用的壳寡糖的潜在有用酶。
