College of Food Science, Southwest University, 2 Tiansheng Road, Beibei, Chongqing 400715, PR China.
Food and Pharmaceutical Engineering Institute, Guiyang University, Guiyang, Guizhou 550005, PR China.
Int J Biol Macromol. 2020 Jul 1;154:916-928. doi: 10.1016/j.ijbiomac.2020.03.169. Epub 2020 Mar 21.
This study aimed to compare the effects of four solvent extractions on the physicochemical properties, antioxidant and hypoglycemic activities of polysaccharides from Mentha haplocalyx (MHPs). The solvent extractions included hot water, citric acid (pH 3.0), 5% NaOH/0.05% NaBH and 0.9% NaCl. Four corresponding MHPs named as MHP-W, MHP-C, MHP-A and MHP-S were obtained, respectively. The experimental results showed that the extraction yields, basic chemical components, monosaccharide contents, molecular weights, antioxidant and hypoglycemic activities of four MHPs were significantly different. However, their thermal stabilities, preliminary structural characteristics and monosaccharide types were similar. MHP-A possessed the highest extraction yield of 9.37 ± 0.24% and the smallest molecular weight. MHP-W had the highest uronic acid content and the largest molecular weight. More specifically, MHP-C exhibited the highest sugar content, the most remarkable antioxidant abilities of DPPH radical scavenging activity and ferric reducing power, and the strongest inhibitory activities on α-glucosidase and α-amylase. The above results indicated that MHP-C extracted with citric acid could be served as a promising bioactive substance for applications in the functional food and medicine industries.
本研究旨在比较四种溶剂提取法对薄荷（Mentha haplocalyx）多糖的理化性质、抗氧化和降血糖活性的影响。溶剂提取法包括热水提取法、柠檬酸（pH 3.0）提取法、5% NaOH/0.05% NaBH 提取法和 0.9% NaCl 提取法。分别得到四种相应的 MHPs，命名为 MHP-W、MHP-C、MHP-A 和 MHP-S。实验结果表明，四种 MHPs 的提取率、基本化学成分、单糖含量、分子量、抗氧化和降血糖活性均有显著差异。然而，它们的热稳定性、初步结构特征和单糖类型相似。MHP-A 的提取率最高，为 9.37±0.24%，分子量最小。MHP-W 的糖醛酸含量最高，分子量最大。具体来说，MHP-C 的糖含量最高，对 DPPH 自由基清除活性和铁还原能力的抗氧化能力最强，对α-葡萄糖苷酶和α-淀粉酶的抑制活性最强。上述结果表明，柠檬酸提取的 MHP-C 可作为一种有前途的生物活性物质，应用于功能性食品和医药行业。
