Antimycobacterial activity of medicinal plants used by the Mayo people of Sonora, Mexico

作者：Wenceslao Coronado Aceves Enrique; Jesus Sanchez Escalante Jose; Lopez Cervantes Jaime; Enrique Robles Zepeda Ramon; Velazquez Carlos; Isabel Sanchez Machado Dalia; Garibay Escobar Adriana^*

来源：Journal of Ethnopharmacology, 2016, 190: 106-115.

DOI：10.1016/j.jep.2016.05.064

• Mycobacterium
• Tuberculosis
• Mayo
• MABA
• REMA
• Rhynchosia

Ethnopharmacological relevance: Tuberculosis (TB) is an infectious disease mainly caused by Mycobacterium tuberculosis (Mtb), which generates 9 million new cases worldwide each year. The Mayo ethnicity of southern Sonora, Mexico is more than 2000 years old, and the Mayos possess extensive knowledge of traditional medicine.
Aims of the study: To evaluate the antimycobacterial activity levels of extracts of medicinal plants used by the Mayos against Mtb and Mycobacterium smegmatis (Msm) in the treatment of TB, respiratory diseases and related symptoms.
Materials and methods: A total of 34 plant species were collected, and 191 extracts were created with n-hexane, dichloromethane, ethyl acetate (EtOAc), methanol and water. Their minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined against Mtb H37Rv using the microplate alamar blue assay (MABA) and against Msm using the resazurin microplate assay (REMA) at 6 and 2 days of exposure, respectively, and at concentrations of 250-1.9 mu g/mL (n-hexane extracts) and 1000-7.81 mu g/mL (extracts obtained with dichloromethane, EtOAc, methanol and water).
Results: Rhynchosia precatoria (Willd.) DC. (n-hexane root extract), Euphorbia albomarginata Torr. and A. Gray. (EtOAc shoot extract) and Helianthus annuus L. (n-hexane stem extract) were the most active plants against Mtb H37Rv, with MICs of 15.6, 250, 250 mu g/mL and MBCs of 31.25, 250, 250 mu g/mL, respectively. R. precatoria (root) was the only active plant against Msm, with MIC and MBC values of >= 250 mu g/mL. None of the aqueous extracts were active.
Conclusions: This study validates the medicinal use of certain plants used by the Mayo people in the treatment of TB and related symptoms. R. precatoria, E. albomarginata and H. annuus are promising plant sources of active compounds that act against Mtb H37Rv. To our knowledge, this is the first time that their antimycobacterial activity has been reported. Crude extracts obtained with n-hexane, EtOAc and dichloromethane were the most active against Mtb H37Rv.

• 出版日期2016-8-22