Instituto de Química, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Hospital da Universidade Federal da Grande Dourados, Dourados, MS, Brazil.
Phytochem Anal. 2018 Sep;29(5):432-445. doi: 10.1002/pca.2747. Epub 2018 Feb 26.
Piper amalago has a distribution from Mexico to Brazil; their aerial parts have been used in folk medicine to treat diuretic and kidney diseases.
The purpose of this study was to obtain a deeper understanding of the chemical composition of essential oils (EOs) extracted from both the leaves and stems of P. amalago, compare them, and evaluate their antilithiasic activity and acute toxicity.
Extraction was performed by hydrodistillation, whereas chemical characterisation by two-dimensional gas chromatography coupled with rapid-scanning quadrupole mass spectrometry (GC×GC/qMS). The antilithiasic activity was evaluated by the effect of the EOs on calcium oxalate crystallisation in vitro. The turbidity index and the number of crystals formed were determined and used as an estimative of the activity. In the acute toxicity assay, the effects of a single oral dose of the EOs in Wistar rats were determined. General behaviour, adverse effects, and mortality were determined.
A total of 322 compounds were identified in the EOs. The sesquiterpenes displayed the highest contribution in leaves EOs among which included bicyclogermacrene and δ-cadinene. Sesquiterpenes and oxygenated sesquiterpenes displayed the highest contribution in EOs from stems, among which included bicyclogermacrene and α-cadinol. The EOs demonstrated an excellent action on the crystals growth inhibition, and the oral dose tested did not induce significant changes in the parameters for acute toxicity.
The oils have a high chemical complexity, and there are differences between their compositions, which could explain the observed differences in antilithiasic activity. The findings support the use of this plant in folk medicine to treat kidney diseases.
Piper amalago 的分布范围从墨西哥到巴西；其地上部分在民间医学中被用于治疗利尿和肾脏疾病。
本研究的目的是更深入地了解从 Piper amalago 的叶和茎中提取的精油（EOs）的化学成分，对它们进行比较，并评估它们的抗结石活性和急性毒性。
通过水蒸馏进行提取，而通过二维气相色谱与快速扫描四极杆质谱联用（GC×GC/qMS）进行化学表征。通过 EOs 对体外草酸钙结晶的影响来评估抗结石活性。测定浊度指数和形成的晶体数，并用作活性的估计。在急性毒性试验中，确定了 EOs 单次口服剂量对 Wistar 大鼠的影响。确定了一般行为、不良反应和死亡率。
共鉴定出 EOs 中的 322 种化合物。倍半萜在叶 EOs 中表现出最高的贡献，其中包括双环金合欢烯和 δ-卡烯。在茎 EOs 中，倍半萜和含氧倍半萜表现出最高的贡献，其中包括双环金合欢烯和α-卡烯醇。EOs 对晶体生长抑制有很好的作用，测试的口服剂量没有引起急性毒性参数的显著变化。
这些油具有很高的化学复杂性，其组成存在差异，这可以解释观察到的抗结石活性差异。这些发现支持将该植物用于民间医学治疗肾脏疾病。
