Post-Graduate Program in Pharmaceutical Sciences, Federal University of Santa Maria, Camobi Campus, Santa Maria, RS, 97105-900, Brazil.
Molecules. 2013 Jul 16;18(7):8342-57. doi: 10.3390/molecules18078342.
Vitex megapotamica (Sprengel) Moldenke belongs to the Verbenaceae family and is popularly known as "tarumã". The antioxidant capacity of fractions and crude extract from the leaves of V. megapotamica were determined in this study through the capacity to remove reactive species and phenolic compounds were quantified in the various fractions. The IC50 (DPPH) ranged from 14.17 ± 0.76 to 37.63 ± 0.98 µg/mL. The ethyl acetate fraction might contain the strongest lipid peroxidation inhibitory compounds with an IC50 of 16.36 ± 5.09 µg/mL, being also the one with the highest content of polyphenols (522.4 ± 1.12 mg/g), flavonoids (220.48 ± 0.30 mg/g) and condensed tannins (3.86 ± 0.53 mg/g). Compounds quantified by HPLC/DAD in the crude extract and fractions were chlorogenic and rosmarinic acids. Higher dosages of the extracts were more effective in reducing levels of plasma protein carbonyls and were also shown to be able to remove reactive species by a 2',7'-dichlorofluorescein diacetate assay, reducing oxidative stress in all tested fractions. Results obtained indicated that V. megapotamica exhibits good potential to prevent diseases caused by the overproduction of free radicals and it might also be used as a potential source of natural antioxidant agents.
Vitex megapotamica (Sprengel) Moldenke 属于马鞭草科，俗称“tarumã”。本研究测定了 V. megapotamica 叶的各馏分和粗提物的清除活性物质能力和酚类化合物的含量。IC50（DPPH）范围为 14.17 ± 0.76 至 37.63 ± 0.98 µg/mL。乙酸乙酯馏分可能含有最强的抑制脂质过氧化的化合物，IC50 为 16.36 ± 5.09 µg/mL，也是多酚（522.4 ± 1.12 mg/g）、类黄酮（220.48 ± 0.30 mg/g）和缩合单宁（3.86 ± 0.53 mg/g）含量最高的馏分。粗提物和馏分中通过 HPLC/DAD 定量的化合物为绿原酸和迷迭香酸。提取物的较高剂量在降低血浆蛋白羰基水平方面更有效，并且还可以通过 2'，7'-二氯荧光素二乙酸酯测定法清除活性物质，降低所有测试馏分的氧化应激。结果表明，V. megapotamica 具有预防自由基过度产生引起的疾病的良好潜力，也可能用作天然抗氧化剂的潜在来源。
