Department of Chemistry and Chemical Processing Technologies, Muğla Vocational School, Muğla Sıtkı Koçman University, 48000 Muğla, Turkey.
Department of Chemistry, Islamia College University Peshawar, Peshawar 25120, Pakistan; Department of Chemistry, Faculty of Sciences, Muğla Sıtkı Koçman University, 48000 Muğla, Turkey.
Int J Biol Macromol. 2020 Dec 15;165(Pt B):2395-2403. doi: 10.1016/j.ijbiomac.2020.10.040. Epub 2020 Oct 13.
Polysaccharides are essential compounds that contribute to the biological activities of mushrooms. Two new galactomannans (Galactomannan I and II) were isolated from R. luteolus and G. adspersum. Their structures were characterized using FT-IR, 1D, and 2D-NMR techniques. Both isolated galactomannans I and II mainly include D-mannose and D-galactose in the molar percentages of 0.81:1.0 and 1:1.4, respectively. The GPC calculation demonstrated that the molecular weights are about 5240 and 5090 Da, respectively. Their structures comprise of β-(1,4)-mannose (Man) backbone units with α-(1,6)-galactose (Gal) single unit as a side group. The anticholinesterase activity of galactomannans was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), spectrophotometrically. Antioxidant activity was also measured by six assays (ABTS, DPPH, O, β-carotene-linoleic acid, metal chelating, and CUPRAC assays). Galactomannan II indicated close inhibitory activity to galantamine against AChE (61.04 ± 0.45%) and BChE (59.70 ± 1.15%) at 50 μg/mL concentration. Nevertheless, both galactomannans showed low antioxidant activity in all tests. This study reveals that mainly, Galactomannan II could be used as a new natural promising anticholinesterase agent.
多糖是蘑菇生物活性所必需的化合物。两种新的半乳甘露聚糖（Galactomannan I 和 II）从 R. luteolus 和 G. adspersum 中分离得到。使用 FT-IR、1D 和 2D-NMR 技术对其结构进行了表征。两种分离得到的半乳甘露聚糖 I 和 II 主要包含摩尔百分比为 0.81:1.0 和 1:1.4 的 D-甘露糖和 D-半乳糖。GPC 计算表明分子量分别约为 5240 和 5090 Da。它们的结构由β-(1,4)-甘露糖（Man）主链单元和α-(1,6)-半乳糖（Gal）单糖作为侧基组成。通过分光光度法测试了半乳甘露聚糖对乙酰胆碱酯酶（AChE）和丁酰胆碱酯酶（BChE）的抑制活性。还通过六种测定法（ABTS、DPPH、O、β-胡萝卜素-亚油酸、金属螯合和CUPRAC 测定法）测量了抗氧化活性。半乳甘露聚糖 II 在 50 µg/mL 浓度下对 AChE（61.04 ± 0.45%）和 BChE（59.70 ± 1.15%）具有与加兰他敏接近的抑制活性。然而，两种半乳甘露聚糖在所有测试中均表现出较低的抗氧化活性。本研究表明，半乳甘露聚糖 II 主要可以用作新的有前途的天然乙酰胆碱酯酶抑制剂。
