Department of Chemistry, Federal Technological University of Paraná (UTFPR), Pato Branco, PR 85503-390, Brazil.
Department of Chemistry, Federal Technological University of Paraná (UTFPR), Pato Branco, PR 85503-390, Brazil.
Food Res Int. 2021 Mar;141:110082. doi: 10.1016/j.foodres.2020.110082. Epub 2020 Dec 29.
The antihyperglicemic activity of crude extract from Moringa oleifera leaves and isolation of phenolic compounds with antioxidant activity using bioguided assay were employed by the first time in leaves cultivated in Brazil. The hydroalcoholic extract (HE) was produced by using ethanol:water (80:20 v/v) and purified by solid-liquid procedure using solvents in ascending order of polarity. The ethyl acetate fraction (Fr-EtOAc) presented high antioxidant potential and it was purified using chromatographic techniques rendering isolated compounds that were identified from the spectral data. The HE extract (500 mg kg) was adimistrated in diabetic rats induced by streptozotocin and chemical markers and lipid peroxidation in liver and kidney were evaluated. The Fr-EtOAc showed high antioxidant potential by FRAP reduction method (1678 µmol Fe g), DPPH and ABTS scavenging methods (526.7 and 671.5 µmol TEAC g respectively) and ORAC assay (3560.6 µmol TEAC g). Therefore, the Fr-EtOAc was purified and yielded three bioactive subfractions (S-12, S-13 abd S-15) that were rechromatoghaphed in HPLC-SemiPrep. After that, two main bioactive glycosylated flavonoids (isoquercitrin and astragalin) and phenolic acid (3-O-caffeoylquinic acid) were obtained. Additionally, the HE extract provided protection against oxidative damage in liver and kidney of diabetic rats ameliorating endogenous antioxidant defenses by increase catalase (CAT), glutathione S-transferase (GST) and non-protein thiol groups (NPSH) levels as well as decreased the lipid peroxidation in these tissues. Our results indicate that three phenolic compounds with high antioxidant activity were isolated and, the chemical composition of HE crude extract, rich in flavonoids glycosylated could be intimately related to antihyperglycemic action. So, it is possible to suggest that these compounds may be used as chemical biomarkers for this plant in Brazil, ensuring quality and supporting the use of aerial parts in tradicional medicine.
巴西种植的辣木叶的粗提物的降血糖活性和使用生物导向测定法分离具有抗氧化活性的酚类化合物的活性，这是首次在辣木叶中进行。采用乙醇：水（80：20v/v）生产水醇提取物（HE），并用溶剂从低极性到高极性顺序的固液程序进行纯化。乙酸乙酯部分（Fr-EtOAc）具有高抗氧化潜力，并用色谱技术进行纯化，得到从光谱数据中鉴定的分离化合物。将 HE 提取物（500mg/kg）施用于链脲佐菌素诱导的糖尿病大鼠，并评估化学标志物和肝、肾的脂质过氧化。Fr-EtOAc 通过 FRAP 还原法（1678µmol Fe/g）、DPPH 和 ABTS 清除法（分别为 526.7 和 671.5µmol TEAC/g）和 ORAC 测定法（3560.6µmol TEAC/g）显示出高抗氧化潜力。因此，Fr-EtOAc 被纯化并产生了三个生物活性亚馏分（S-12、S-13 和 S-15），这些亚馏分在 HPLC-SemiPrep 中再次进行色谱分离。之后，得到了两种主要的生物活性糖基化类黄酮（异槲皮苷和槲皮苷）和酚酸（3-O-咖啡酰奎宁酸）。此外，HE 提取物对糖尿病大鼠肝、肾的氧化损伤提供了保护作用，通过增加过氧化氢酶（CAT）、谷胱甘肽 S-转移酶（GST）和非蛋白巯基（NPSH）水平，改善内源性抗氧化防御，降低这些组织的脂质过氧化。我们的结果表明，分离得到了三种具有高抗氧化活性的酚类化合物，HE 粗提取物的化学成分富含糖基化类黄酮，可能与降血糖作用密切相关。因此，有可能建议将这些化合物用作巴西该植物的化学标志物，以确保质量，并支持使用该植物的地上部分在传统医学中。
