The main objective of this study is to compare the extraction efficiency, phenolic composition and antioxidant activity of fallen red leaves of the tropical almond (Terminalia catappa) using two extraction methods. The leaf was extracted under different conditions: soaking (12 and 24 h) and pulse electric fields (0.5 and 0.75 kV/cm). The results demonstrated that the highest total phenolic content (TPC) and higher antioxidant activity were related to the 50% concentration of red leaf extract. The evaluation of the two extraction methods revealed that the extract of red leaf obtained via PEF with 0.75 kV/cm field strength had the highest TPC and antioxidant activity (DPPH). Finally, red leaf phenolic compounds were identified and reported by HPLC.

中文翻译：

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脉冲电场辅助从热带杏仁红叶中提取酚类抗氧化剂

这项研究的主要目的是比较两种提取方法对热带杏仁（Terminalia catappa）落叶红叶的提取效率，酚类成分和抗氧化活性。在不同条件下提取叶片：浸泡（12和24 h）和脉冲电场（0.5和0.75 kV / cm）。结果表明，最高的总酚含量（TPC）和较高的抗氧化活性与红叶提取物的50％浓度有关。对两种提取方法的评估表明，通过PEF获得的0.75 kV / cm场强的红叶提取物具有最高的TPC和抗氧化活性（DPPH）。最后，红叶酚类化合物被鉴定并通过HPLC报告。