Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.
Department of Chemistry, Tamkang University, New Taipei City 25137, Taiwan.
Molecules. 2018 Dec 30;24(1):120. doi: 10.3390/molecules24010120.
Champ., a medicinal herb collected in Vietnam, has been reported to show several potent bioactivities, including anti-NO, enzyme inhibition, hypoglycemic and antidiabetic effects. Recently, the antioxidant activity of Champ. trunk bark (ELCTB) has also been reported. However, the active antioxidant and anti-NO constituents existing in ELCTB have not been reported in the literature. The objective of this study was to purify the active antioxidants from ELCTB and investigate the anti-NO effect of the major constituents. Twenty-two phenolics isolated from ELCTB, including 12 compounds newly isolated in this study (⁻) and 10 constituents obtained from our previous work, were evaluated for their antioxidant activity. Of these, 12 compounds (⁻, , ⁻, ⁻) showed a potent antioxidant capacity (FRS50 = 7.8⁻58.11 µg/mL), in comparison to α-tocopherol (FRS50 = 23 µg/mL). In the anti-NO activity tests, Walterolactone A (1a) and B (1b) β-d-glucopyranoside () demonstrated the most effective and comparable activity to that of quercetin with max inhibition and IC values of 100%, 1.3 µg/mL, and 100%, 1.21 µg/mL, respectively. The crude extract and its major compounds showed no cytotoxicity on normal cells. Notably, three constituents (, , and ) were identified as new compounds, another three constituents, including , , and , were found to be new natural products, constituents and were determined to be new antioxidants, and compound was reported to have novel potent anti-NO activity for the first time. The results of this study contribute to the enrichment of new natural products and compounds, as well as the novel biological activity of constituents isolated from Champ. The current study also indicates ELCTB as a rich natural source of active phenolics. It is suggested that ELCTB could be developed as a health food with promising antioxidant and anti-NO effects, as well as other beneficial biological activities.
荩草，一种在越南采集的药用植物，已被报道具有多种强效的生物活性，包括抗一氧化氮、酶抑制、降血糖和抗糖尿病作用。最近，荩草树干皮（ELCTB）的抗氧化活性也有报道。然而，ELCTB 中存在的活性抗氧化和抗一氧化氮成分在文献中尚未报道。本研究的目的是从 ELCTB 中分离纯化活性抗氧化剂，并研究主要成分的抗一氧化氮作用。从 ELCTB 中分离得到的 22 种酚类化合物，包括本研究新分离的 12 种化合物（⁻）和我们以前工作中得到的 10 种成分，评估了它们的抗氧化活性。其中，12 种化合物（⁻、⁻、⁻）表现出很强的抗氧化能力（FRS50=7.8⁻58.11μg/mL），与 α-生育酚（FRS50=23μg/mL）相当。在抗一氧化氮活性测试中，Walterolactone A（1a）和 B（1b）β-d-吡喃葡萄糖苷（）表现出与槲皮素最有效和可比的活性，最大抑制率和 IC 值分别为 100%，1.3μg/mL 和 100%，1.21μg/mL。粗提取物及其主要成分对正常细胞无细胞毒性。值得注意的是，有三个成分（⁻、⁻和）被鉴定为新化合物，另外三个成分，包括、和，被发现是新的天然产物，成分和被确定为新的抗氧化剂，化合物首次被报道具有新的强效抗一氧化氮活性。本研究结果丰富了从荩草中分离得到的新天然产物和化合物以及成分的新生物活性。本研究还表明，ELCTB 是一种富含活性酚类物质的天然资源。建议将 ELCTB 开发为具有良好抗氧化和抗一氧化氮作用以及其他有益生物活性的保健品。
