College of Life Sciences, China Jiliang University, Hangzhou, Zhejiang 310018, People's Republic of China.
College of Life Sciences, China Jiliang University, Hangzhou, Zhejiang, 310018, China; Liang Xin College, China Jiliang University, Hangzhou, Zhejiang 310018, People's Republic of China.
Int J Med Mushrooms. 2022;24(2):49-62. doi: 10.1615/IntJMedMushrooms.2021041906.
An effective method of polysaccharide extraction from Auricularia auricula (AAPs) by mannanase was developed and optimized by response surface methodology in which the ABTS+ [diammonium 2,2'-azino-bis(3-ethylben-zothiazoline-6-sulfonate radical] scavenging rate was the response. AAPs were graded by stepwise ethanol precipitation with concentrations of 5, 10, 15, and 20% ethanol successively. The fractions with a strong radical scavenging rate were obtained, and then their antioxidant stress effect was studied using Caenorhabditis elegans as a model organism. The ABTS+ scavenging rate of AAPs could reach 37.95 ± 0.53% at a temperature of 55°C, a time of 4 h, a liquid-to-material ratio of 58 mL/1 g, and an enzyme-to-substrate ratio of 2.97%. AAP-20 obtained by 20% ethanol with a strong radical scavenging rate was a heteropolysaccharide composed of mannose, glucose, galactose, xylose, and glucuronic acid. AAP-20 could significantly prolong the lifespan of C. elegans under oxidative stress conditions induced by methyl viologen or hydrogen peroxide, and it could also enhance the activity of antioxidant enzymes including catalase, glutathione reductase, and superoxide dismutase at 0.50 mg/mL (P < 0.05). These studies showed that AAPs prepared with mannanase had a significant protective effect against damage induced by intracellular radical generating agents.
一种通过甘露聚糖酶从银耳（AAPs）中提取多糖的有效方法，通过响应面法进行了开发和优化，其中 ABTS+[二铵 2,2'-偶氮双（3-乙基苯并噻唑啉-6-磺酸）自由基]清除率为响应值。AAPs 通过逐步用 5%、10%、15%和 20%乙醇进行分级沉淀。获得具有较强自由基清除率的级分，然后使用秀丽隐杆线虫作为模型生物研究其抗氧化应激作用。在 55°C、4 h、液料比为 58 mL/1 g 和酶底物比为 2.97%的条件下，AAPs 的 ABTS+清除率可达 37.95±0.53%。用 20%乙醇获得的具有较强自由基清除率的 AAP-20 是一种由甘露糖、葡萄糖、半乳糖、木糖和葡萄糖醛酸组成的杂多糖。AAP-20 能显著延长甲基紫精或过氧化氢诱导的氧化应激条件下秀丽隐杆线虫的寿命，在 0.50mg/mL 时还能增强过氧化氢酶、谷胱甘肽还原酶和超氧化物歧化酶等抗氧化酶的活性（P<0.05）。这些研究表明，用甘露聚糖酶制备的 AAPs 对细胞内自由基生成剂诱导的损伤具有显著的保护作用。
