The long history of using plant species as medicines worldwide provides clues for the search for bioactive phytochemicals. One of the important traditional medicinal plant species of Pakistan is Dryopteris ramosa (Dryopteridaceae). The fronds of Dryopteris ramosa are traditionally used for the treatment of gastric ulcer and constipation. The crude methanol extract and aqueous fraction of Dryopteris ramosa exhibited strong free radical scavenging potential. Two xanthonoid compounds, mangiferin and isomangiferin, were isolated from the aqueous fraction of Dryopteris ramosa by chromatographic techniques (CC Sephadex LH20, followed by MPLC and purified by preparative TLC). Their structures were confirmed by spectroscopic analysis MS, NMR (1H, 13C, HSQC and HMBC). This is the first report on isolation of mangiferin and isomangiferin from Dryopteris genus though previously reported in other fern genera, e.g., Cystopteris, Acystopteris, Gymnocarpium and Asplenium. The antioxidant potential of mangiferin (60.34 ± 0.14 μg/mL) and isomangiferin (55.98 ± 0.39 μg/mL) was comparable to ascorbic acid (57.97 ± 0.93 μg/mL), thus representing promising antioxidant agents against oxidative stress. The investigation of the mechanism of free radical scavenging by mangiferin and isomangiferin showed that the catechol moiety was involved in quenching of free radicals. This study justified the traditional use of Dryopteris ramosa confirming the pharmacological properties of isolated compounds. Further phytochemical studies on Dryopteris ramosa are needed for identification of new bioactive phytochemicals in this plant of ethnobotanical relevance.

在世界范围内使用植物物种作为药物的悠久历史为寻找生物活性植物化学物质提供了线索。巴基斯坦重要的传统药用植物之一是Dramopteris ramosa（Dryopteridaceae）。传统上，鳞翅目（Dryopteris ramosa）叶用于治疗胃溃疡和便秘。粗甲醇提取物和毛鳞Dry的含水部分表现出很强的清除自由基的能力。从毛鳞毛虫的水部分中分离出两种黄酮类化合物，芒果苷和异血管生成素通过色谱技术（CC Sephadex LH20，然后是MPLC，并通过制备型TLC纯化）。通过光谱分析MS，NMR（1H，13C，HSQC和HMBC）确认了它们的结构。这是从鳞毛蕨属芒果和isomangiferin隔离的第一份报告，虽然以前在其他蕨属，如报道Cystopteris，Acystopteris，羽节和铁角蕨。芒果苷（60.34±0.14μg/ mL）和异麦芽香素（55.98±0.39μg/ mL）的抗氧化潜力与抗坏血酸（57.97±0.93μg/ mL）相当，因此代表了有希望的抗氧化应激的抗氧化剂。芒果苷和异血管生成素清除自由基的机理研究表明，儿茶酚部分参与自由基的猝灭。这项研究证明了传统的Dryopteris ramosa的使用是正确的，从而证实了分离化合物的药理特性。为了鉴定该植物中与植物植物相关的新的生物活性植物化学物质，需要对毛鳞毛虫进行进一步的植物化学研究。