The objectives of the current study are to evaluate the traditionally used medicinal plants Andrographis paniculata for in vitro anti-malarial activity against human malarial parasite Plasmodium falciparum and to further characterize the anti-malarial active extract of A. paniculata using spectroscopic and chromatographic methods. The chloroform extract of A. paniculata displayed anti-malarial activity with IC50 values 6.36 μg/ml against 3D7 strain and 5.24 μg/ml against K1 strains respectively with no evidence of significant cytotoxicity against mammalian cell line (CC50 > 100 μg/ml). LC-MS analysis of the extract led to the identification of 59 compounds based on their chromatographic and mass spectrometric features (a total of 35 compounds are present in positive ion and 24 compounds in negative ion mode). We have identified 5 flavonoids and 30 compounds as diterpenoids in positive ion mode, while in the negative mode all identified compounds were diterpenoids. Characterization of the most promising class of compound diterpenoids using HPLC-LC-ESI-MS/MS was also undertaken. The in vitro results undoubtedly validate the traditional use of A. paniculata for the treatment of malaria. The results have led to the identification of diterpenoids from IGNTU_06 extract as potential anti-malarial compounds that need to be further purified and analyzed in anti-malarial drug development programs.

中文翻译：

---

二萜类化合物作为来自穿心莲的潜在抗疟化合物

本研究的目的是评估传统使用的药用植物穿心莲对人疟原虫恶性疟原虫的体外抗疟活性，并使用光谱和色谱方法进一步表征穿心莲的抗疟活性提取物。A. paniculata 的氯仿提取物显示出抗疟疾活性，对 3D7 菌株的 IC50 值为 6.36 μg/ml，对 K1 菌株的 IC50 值分别为 5.24 μg/ml，没有证据表明对哺乳动物细胞系有显着的细胞毒性（CC50 > 100 μg/ml）。对提取物进行 LC-MS 分析，基于其色谱和质谱特征鉴定了 59 种化合物（总共 35 种化合物以正离子模式存在，24 种化合物以负离子模式存在）。我们在正离子模式下鉴定了 5 种黄酮类化合物和 30 种化合物为二萜，而在负离子模式下，所有鉴定的化合物都是二萜。还进行了使用 HPLC-LC-ESI-MS/MS 表征最有希望的一类化合物二萜。体外结果无疑验证了 A. paniculata 用于治疗疟疾的传统用途。结果导致从 IGNTU_06 提取物中鉴定出二萜类化合物作为潜在的抗疟化合物，需要在抗疟药物开发计划中进一步纯化和分析。体外结果无疑验证了 A. paniculata 用于治疗疟疾的传统用途。结果导致从 IGNTU_06 提取物中鉴定出二萜类化合物作为潜在的抗疟化合物，需要在抗疟药物开发计划中进一步纯化和分析。体外结果无疑验证了 A. paniculata 用于治疗疟疾的传统用途。结果导致从 IGNTU_06 提取物中鉴定出二萜类化合物作为潜在的抗疟化合物，需要在抗疟药物开发计划中进一步纯化和分析。