Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Lodz, 1 Muszynskiego St., 90-151 Lodz, Poland.
Molecules. 2022 Oct 20;27(20):7081. doi: 10.3390/molecules27207081.
Cotoneaster species have gained significant importance in traditional Asian medicine for their ability to prevent and treat hyperglycemia and diabetes. Therefore, in this study, some aspects of the beneficial health effects of hydromethanolic extracts of C. bullatus, C. zabelii, and C. integerrimus leaves and fruits were evaluated, including their influence on α-glucosidase, α-amylase, and nonenzymatic protein glycation. The activity was investigated in relation to the polyphenolic profile of the extracts determined by UV-spectrophotometric and HPLC-PDA-fingerprint methods. It was revealed that all leaf and fruit extracts are a promising source of biological components (caffeic acid pseudodepsides, proanthocyanidins, and flavonols), and the leaf extracts of C. bullatus and C. zabelii contain the highest levels of polyphenols (316.3 and 337.6 mg/g in total, respectively). The leaf extracts were also the most effective inhibitors of digestive enzymes and nonenzymatic protein glycation. IC50 values of 8.6, 41.8, and 32.6 µg/mL were obtained for the most active leaf extract of C. bullatus (MBL) in the α-glucosidase, α-amylase, and glycation inhibition tests, respectively. In the kinetic study, MBL was displayed as a mixed-type inhibitor of both enzymes. The correlations between the polyphenol profiles and activity parameters (|r| > 0.72, p < 0.05) indicate a significant contribution of proanthocyanidins to the tested activity. These results support the traditional use of Cotoneaster leaves and fruits in diabetes and suggest their hydrophilic extracts be promising in functional applications.
栒子属植物在传统亚洲医学中因其具有预防和治疗高血糖和糖尿病的能力而受到重视。因此，在这项研究中，评估了 C. bullatus、C. zabelii 和 C. integerrimus 的叶子和果实的水甲醇提取物的一些有益健康的影响，包括它们对α-葡萄糖苷酶、α-淀粉酶和非酶蛋白糖基化的影响。研究了提取物的多酚谱与活性之间的关系，通过紫外分光光度法和 HPLC-PDA 指纹图谱法确定。结果表明，所有叶和果实提取物都是生物成分（咖啡酸伪二萜、原花青素和黄酮醇）的有前途的来源，并且 C. bullatus 和 C. zabelii 的叶提取物含有最高水平的多酚（分别为 316.3 和 337.6mg/g）。叶提取物也是消化酶和非酶蛋白糖基化的最有效抑制剂。在α-葡萄糖苷酶、α-淀粉酶和糖基化抑制试验中，C. bullatus （MBL）最活跃的叶提取物的 IC50 值分别为 8.6、41.8 和 32.6µg/mL。在动力学研究中，MBL 被显示为两种酶的混合型抑制剂。多酚谱与活性参数之间的相关性（|r|＞0.72，p＜0.05）表明原花青素对测试活性有重要贡献。这些结果支持了栒子属植物在糖尿病中的传统用途，并表明其亲水性提取物在功能应用中具有广阔的前景。
