CQM - Centro de Química da Madeira, Universidade da Madeira, Campus da Penteada, 9020-105, Funchal, Portugal.
Department of Physical and Analytical Chemistry, Faculty of Experimental Sciences, University of Jaén, Campus Las Lagunillas, E-23071, Jaén, Spain.
Food Chem Toxicol. 2019 Jan;123:443-452. doi: 10.1016/j.fct.2018.11.006. Epub 2018 Nov 5.
Rubus grandifolius Lowe (wild blackberries) is an endemic species from Madeira Archipelago (Portugal) used in folk medicine for alleviating diabetic complications. In this work, R. grandifolius methanolic extracts were analysed for in vitro inhibitory effect on digestive enzymes linked to type-2 diabetes, as well as aldose reductase activity and protein glycation. The phenolic composition, antioxidant and cytotoxic activities were also determined. Methanolic extracts exhibited strong inhibition of glucosidases (α- and β), but were less potent for α-amylase and pancreatic lipase when compared to current pharmaceutical drugs. The total phenolic content determined by HPLC-DAD varied between 92.96 - 97.47 and 118.01-137.41 mg g of dry extract for berries and leaves, respectively. Fifty polyphenols were quantified, anthocyanins and ellagitannins being the main compounds. Cyanidin-3-glucoside was identified as one of the main hypoglycaemic and hypolipidemic agents in all extracts. R. grandifolius also prevented glycation of bovine-serum albumin (BSA) and showed strong radical scavenging activity against tested free radicals. At low concentration, the extracts were not cytotoxic against Caco-2 cells. Based on the results of this study, wild blackberry extracts demonstrated a potential beneficial effect on the control/management of type-2 diabetes mellitus, validating their use in folk medicine.
粗叶悬钩子（野黑莓）是一种来自马德拉群岛（葡萄牙）的特有物种，在民间医学中用于缓解糖尿病并发症。在这项工作中，分析了粗叶悬钩子的甲醇提取物对与 2 型糖尿病相关的消化酶的体外抑制作用，以及醛糖还原酶活性和蛋白质糖化作用。还测定了其酚类成分、抗氧化和细胞毒性活性。甲醇提取物对糖苷酶（α-和β）表现出强烈的抑制作用，但与目前的药物相比，对α-淀粉酶和胰脂肪酶的抑制作用较弱。通过 HPLC-DAD 测定的总酚含量在浆果和叶子的干提取物中分别为 92.96-97.47 和 118.01-137.41 mg/g。定量了 50 种多酚，其中花色苷和鞣花单宁是主要化合物。在所有提取物中，矢车菊-3-葡萄糖苷被鉴定为主要的降血糖和降血脂剂之一。粗叶悬钩子还能防止牛血清白蛋白（BSA）的糖化，并对测试的自由基表现出强烈的清除活性。在低浓度下，提取物对 Caco-2 细胞没有细胞毒性。基于这项研究的结果，野生黑莓提取物对 2 型糖尿病的控制/管理具有潜在的有益作用，验证了其在民间医学中的应用。
