Introduction: Traditional healing is often the preferred form of therapy especially in rural and resource-limited communities. The extracts of plants are used to treat many diseases such as arthritis and chronic pain. Four medicinal plant species, namely, Acokanthera oppositifolia, Plantago lanceolata, Conyza canadensis and Artemisia vulgaris used in Southern Africa to treat pain and inflammation-related diseases were selected for evaluation in laboratory-based experiments.
Methods: The selected plant species were evaluated for phytochemical content, antioxidant and anti-inflammatory activities, as well as cytotoxicity effects against mammalian cells in culture.
Results: The results indicated that the n-hexane and chloroform extracts of P. lanceolata had the best antioxidant activities with an IC₅₀=0.41 μg/mL. Also, the acetone extracts of P. lanceolata had 93.76% nitric oxide (NO) inhibition. However, the chloroform and n-hexane extracts of C. canadensis produced NO inhibition of 98.53% and 99.2%, respectively, at 100 μg/mL with IC₅₀=17.69 μg/mL. Furthermore, the ethyl acetate extracts also had promising NO inhibitory activity (96.33%), but the cytotoxicity results with cell viabilities of 5.31%, 5.7% and 5.89%, respectively, suggested that the observed activity was due to a cytotoxic effect. Acetone extracts of C. canadensis were also cytotoxic at 30 μg/mL with 6.07–6.67% cell viabilities compared with the acetone extracts of P. lanceolata (99.57%).
Conclusion: The results partially validate the ethnomedicinal uses of the selected plant species used for inflammation-related conditions. However, because some of the extracts had potential cytotoxic effects, caution is advised in their use, especially those consumed orally.

Keywords: nitric oxide, free radicals, medicinal plants, South Africa, inflammation


中文翻译：

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抑制四种南非药用植物的一氧化氮产生和自由基清除活性。

简介：传统疗法通常是首选的治疗方式，尤其是在农村和资源有限的社区。植物提取物用于治疗许多疾病，如关节炎和慢性疼痛。在实验室实验中选择了四种药用植物物种，即在南部非洲用于治疗疼痛和炎症相关疾病的Acokanthera oppositifolia、Plantago lanceolata、Conyza canadensis和Artemisia vulgaris 。
方法：对所选植物物种的植物化学成分、抗氧化和抗炎活性以及对培养中的哺乳动物细胞的细胞毒性作用进行评估。
结果：结果表明，nP. lanceolata的正己烷和氯仿提取物具有最好的抗氧化活性，IC ₅₀ =0.41 μg/mL。此外，P. lanceolata的丙酮提取物具有 93.76% 的一氧化氮 (NO) 抑制作用。然而，C. canadensis的氯仿和正己烷提取物在 100 μg/mL 时产生的 NO 抑制分别为 98.53% 和 99.2%，IC ₅₀ =17.69 μg/mL。此外，乙酸乙酯提取物还具有良好的 NO 抑制活性（96.33%），但细胞毒性结果分别为 5.31%、5.7% 和 5.89%，表明观察到的活性是由于细胞毒性作用所致。C. canadensis的丙酮提取物与P. lanceolata的丙酮提取物(99.57%)相比，在 30 μg/mL 时也具有细胞毒性，细胞活力为 6.07-6.67% 。
结论：结果部分验证了用于炎症相关疾病的选定植物物种的民族医学用途。然而，由于某些提取物具有潜在的细胞毒性作用，因此建议谨慎使用，尤其是口服的。

关键词：一氧化氮，自由基，药用植物，南非，炎症