Silk Biotechnology Key Laboratory of Suzhou City, Medical College of Soochow University, Suzhou 215123, China.
Evid Based Complement Alternat Med. 2014;2014:569652. doi: 10.1155/2014/569652. Epub 2014 Jan 22.
The biological activities of the branch bark ethanol extract (BBEE) in the mulberry Morus alba L. were investigated. The determination of active component showed that the flavonoids, phenols, and saccharides are the major components of the ethanol extract. The BBEE had a good scavenging activity of the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical with around 100 μ g/mL of IC50 value. In vitro assay revealed that the BBEE strongly inhibited both α -glucosidase and sucrase activities whose IC50 values were 8.0 and 0.24 μ g/mL, respectively. The kinetic analysis showed that the BBEE as a kind of α -glucosidase inhibitor characterized a competitive inhibition activity. Furthermore, the carbohydrate tolerance of the normal mice was obviously enhanced at 0.5 h (P < 0.05) and 1.0 h (P < 0.05) after the BBEE intragastric administration as compared to negative control. At 0.5, 1.0, 1.5, and 2.0 h after the intragastric administration with starch, the postprandial hyperglycemia of the type 2 diabetic mice can be significantly decreased (P < 0.01) by supplying various concentrations of the BBEE (10-40 mg/kg body weight). Therefore, the BBEE could effectively inhibit the postprandial hyperglycemia as a novel α -glucosidase activity inhibitor for the diabetic therapy.
研究了桑科植物白桑的枝皮乙醇提取物（BBEE）的生物活性。活性成分的测定表明，黄酮类、酚类和糖类是乙醇提取物的主要成分。BBEE 对 1,1-二苯基-2-苦基肼（DPPH）自由基具有良好的清除活性，IC50 值约为 100 μ g/mL。体外试验表明，BBEE 强烈抑制α -葡萄糖苷酶和蔗糖酶的活性，其 IC50 值分别为 8.0 和 0.24 μ g/mL。动力学分析表明，BBEE 作为一种α -葡萄糖苷酶抑制剂，具有竞争性抑制活性。此外，与阴性对照组相比，BBEE 灌胃给药后 0.5 h（P < 0.05）和 1.0 h（P < 0.05），正常小鼠的耐糖能力明显增强。灌胃淀粉后 0.5、1.0、1.5 和 2.0 h，不同浓度的 BBEE（10-40 mg/kg 体重）可显著降低 2 型糖尿病小鼠的餐后高血糖（P < 0.01）。因此，BBEE 可有效抑制餐后高血糖，作为一种新型的α -葡萄糖苷酶活性抑制剂用于糖尿病治疗。
