The bark anatomy was analysed, as was the overall chemical composition (extractives, lignin, suberin, ash and polysaccharides), and a quantitative elemental analysis was performed of the bark and two tannin extracts (extracted with water only and with a mixture of water and Na2SO3). The phenolic composition and antioxidant activity of the bark extracts were quantified. The results indicated that the bark is composed of conductive phloem, nonconductive phloem, rhytidome, crystals and secretory cells. The average chemical composition was 15.9 % extractives, 35.3 % total lignin, 1.9 % suberin, 15.4 % ash and 31.5 % polysaccharides. The condensed tannin yield in the extract obtained with water alone was 5.1 %, and that in the treatment with water and Na2SO3 was 8.1 %. The ethanol-water extract had a high phenolic content (112.6 mg GAE g−1 extract). The bark extract showed strong antioxidant activity, reaching 83.5 % inhibition of DPPH free radicals, which was higher than the value of 75.0 % for the commercial antioxidant BHT at the same concentration. These results demonstrate that Protium tenuifolium is a potential natural Amazonian source of phenolic compounds and antioxidants and can be used for medicinal purposes and the production of various sustainable products, such as cosmetics.

中文翻译：

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Protium tenuifolium Engl 树皮的表征。来自亚马逊生物群落，作为天然抗氧化剂的来源

对树皮解剖结构以及整体化学成分（提取物、木质素、木栓质、灰分和多糖）进行了分析，并对树皮和两种单宁提取物（仅用水提取以及用水和水的混合物提取）进行了定量元素分析。钠2所以3）。对树皮提取物的酚类成分和抗氧化活性进行了定量。结果表明，树皮由导电韧皮部、非导电韧皮部、褶皱、晶体和分泌细胞组成。平均化学成分为 15.9% 提取物、35.3% 总木质素、1.9% 木栓质、15.4% 灰分和 31.5% 多糖。仅用水提取的提取物中的缩合单宁收率为 5.1%，而用水和 Na2 处理后的提取物中的缩合单宁收率为 5.1%。2所以3为 8.1%。乙醇-水提取物具有高酚含量（112.6 mg GAE g−1提炼）。树皮提取物表现出很强的抗氧化活性，对DPPH自由基的抑制率达到83.5%，高于同浓度的市售抗氧化剂BHT的75.0%。这些结果表明细叶氕是亚马逊地区酚类化合物和抗氧化剂的潜在天然来源，可用于医药目的和生产各种可持续产品，例如化妆品。