The objective of the current investigation was to evaluate the in vitro free radical scavenging properties of fruit extracts of two varieties of Psidium guajava L. (PG) i.e., Lalit (LA) and Allahabad safeda (AS). The ethanolic fruit extracts of LA and AS of PG were obtained from the soxhlet extraction procedure and the same was used for in vitro antioxidant assays. Total phenols, flavonoid contents and free radical scavenging assays viz., ABTS, DPPH, nitric oxide and superoxide were analysed at 100, 200, 300, 400, 500, 600 and 700 μg/mL concentrations. Phytochemical investigation exhibited higher phenols, flavonoid contents in fruit extracts of LA compared to AS. The fruit extracts of PG showed remarkable ABTS, DPPH, nitric oxide and superoxide free radical scavenging activity in a dose dependent manner. The fruit extracts of LA exhibited higher free radical scavenging activity in contrast to AS. The present investigation revealed, a high in vitro antioxidant property of LA due to its higher phenolic content. Hence, the fruit extract of Psidium guajava L. can be used in therapeutics for the treatment of pathologic conditions involving free radicals.

中文翻译：

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番石榴果实提取物体外清除自由基活性的筛选。

当前调查的目的是评估两种番石榴 (PG) 即 Lalit (LA) 和 Allahabad safeda (AS) 的果实提取物的体外自由基清除特性。LA 的乙醇果实提取物和 PG 的 AS 提取物是从索氏提取过程中获得的，同样用于体外抗氧化试验。对 100、200、300、400、500、600 和 700 μg/mL 浓度的总酚、类黄酮含量和自由基清除试验（即 ABTS、DPPH、一氧化氮和超氧化物）进行了分析。植物化学研究表明，与 AS 相比，LA 水果提取物中的酚类、类黄酮含量更高。PG 的果实提取物以剂量依赖性方式显示出显着的 ABTS、DPPH、一氧化氮和超氧化物自由基清除活性。与 AS 相比，LA 的水果提取物表现出更高的自由基清除活性。目前的研究表明，由于酚类物质含量较高，LA 具有很高的体外抗氧化性能。因此，番石榴果实提取物可用于治疗涉及自由基的病理状况。