Antioxidant and Anti-Inflammatory Activities of Unexplored Brazilian Native Fruits

Brazilian native fruits are unmatched in their variety, but a poorly explored resource for the development of food and pharmaceutical products. The aim of this study was to evaluate the phenolic composition as well as the antioxidant and anti-inflammatory activities of the extracts of leaves, seeds, and pulp of four Brazilian native fruits (Eugenia leitonii, Eugenia involucrata, Eugenia brasiliensis, and Eugenia myrcianthes). GC—MS analyses of the ethanolic extracts showed the presence of epicatechin and gallic acid as the major compounds in these fruits. Antioxidant activity was measured using synthetic DPPH free-radical scavenging, β-carotene bleaching assay, and reactive oxygen species (ROO·, O2·−, and HOCl). The fruit extracts also exhibited antioxidant effect against biologically relevant radicals such as peroxyl, superoxide, and hypochlorous acid. In general, the pulps were the fruit fractions that exhibited the lowest antioxidant activities, whereas the leaves showed the highest ones. The anti-inflammatory activity was assessed in an in vivo model using the carrageenan-induced neutrophil migration assay, which evaluates the inflammatory response in the acute phase. The pulp, seeds, and leaves of these fruits reduced the neutrophil influx by 40% to 64%. Based on these results, we suggest that the anti-inflammatory activity of these native fruits is related to the modulation of neutrophil migration, through the inhibition of cytokines, chemokines, and adhesion molecules, as well as to the antioxidant action of their ethanolic extracts in scavenging the free-radicals released by neutrophils. Therefore, these native fruits can be useful to produce food additives and functional foods.

巴西本土水果品类丰富、得天独厚，但在食品与医药产品开发领域仍属开发程度极低的未充分利用资源。本研究旨在评估四种巴西本土水果——莱顿番樱桃（Eugenia leitonii）、总苞番樱桃（Eugenia involucrata）、巴西番樱桃（Eugenia brasiliensis）及香桃木叶番樱桃（Eugenia myrcianthes）——的叶、种子与果肉提取物的酚类组成，并考察其抗氧化与抗炎活性。气相色谱-质谱联用（GC-MS）分析显示，这些水果的乙醇提取物中，表儿茶素与没食子酸为主要成分。本研究采用二苯基苦基苯肼（DPPH）自由基清除实验、β-胡萝卜素漂白法，以及活性氧（ROO·、O2·−与次氯酸（HOCl））清除实验来测定抗氧化活性；结果表明，上述水果提取物对过氧自由基、超氧阴离子及次氯酸等生物学相关自由基同样具有抗氧化效应。总体而言，果肉组分的抗氧化活性最低，而叶片组分的抗氧化活性最高。抗炎活性则通过角叉菜胶诱导的中性粒细胞迁移实验这一体内模型进行评估，该实验用于检测急性阶段的炎症反应。实验发现，这些水果的果肉、种子与叶片可使中性粒细胞浸润程度降低40%至64%。基于上述结果，本研究认为这些本土水果的抗炎活性，与其通过抑制细胞因子、趋化因子及黏附分子以调控中性粒细胞迁移的作用机制，以及乙醇提取物清除中性粒细胞释放的自由基的抗氧化活性密切相关。因此，这些巴西本土水果可用于制备食品添加剂与功能性食品。