Tuberculosis (TB) remains a public health challenge and one of the leading causes of death worldwide. TB is preventable and curable. However, treatment of tuberculosis has continued to be difficult as a result of rapid increase of multidrug and extensively drug resistant strains of Mycobacterium tuberculosis. Medicinal plants have for centuries been traditionally used in treatment of tuberculosis and similar ailments. They possess antimicrobial properties which render them a new hope as a source of novel bioactive leads in the development of antimycobacterial agents. In this study, 2 plant species commonly used traditionally in Uganda for treatment of tuberculosis, Zanthoxylum leprieurii and Rubia cordifolia were screened for in vitro antimycobacterial activity against Mycobacterium tuberculosis strains; pan sensitive MTB H37Rv, Rifampicin resistant TMC 331 strain and two wild strains (one rifampicin resistant and another one rifampicin susceptible). Antimycobacterial activity of aqueous, ethanolic and methanolic plant extracts was determined using Resazurin Microtiter Assay (REMA). Both plant extracts exhibited significant in vitro antimycobacterial activity against all strains of Mycobacterium tuberculosis. Minimum inhibitory concentrations (MIC) of methanolic crude extracts of both plants ranged from 23.4 μg/mL to 187.5 μg/mL. Comparatively, methanol extracts of both plants possessed superior antimycobacterial activity against all Mycobacterium tuberculosis strains. Our findings indicated that both plants exhibited activity against susceptible and resistant strains of Mycobacterium tuberculosis. While antimycobacterial activity of Z. leprieurii confirms results from previous studies, activity of the extracts of R. cordifolia is reported for the first time in East Africa. Further studies aimed at determining the effects of combination of these plant extracts and standard anti-TB drugs should be carried out.
References
[1]
World Health Organization (2021) Global Tuberculosis Report 2021. World Health Organization, Geneva.
[2]
Daletos, G., et al. (2015) Callyaerins from the Marine Sponge Callyspongia aerizusa: Cyclic Peptides with Antitubercular Activity. Journal of Natural Products, 78, 1910-1925. https://doi.org/10.1021/acs.jnatprod.5b00266
[3]
Orodho, J.A., et al. (2011) Local Management of Tuberculosis by Traditional Medicine Practitioners in Lake Victoria Region. The Open Complementary Medicine Journal, 2011, 1-9. https://doi.org/10.2174/1876391X01103010001
[4]
Wright, A., et al. (2006) Emergence of Mycobacterium tuberculosis with Extensive Resistance to Second-Line Drugs—Worldwide, 2000-2004. Morbidity and Mortality Weekly Report, 55, 301-306.
[5]
Camp, R., et al. (2006) What’s in the Pipeline: New HIV Drugs, Vaccines, Microbicides, HCV and TB Therapies in Clinical Trials. Treatment Action Group.
[6]
Singh, B., et al. (2015) Plants as Future Source of Anti-Mycobacterial Molecules and Armour for Fighting Drug Resistance. Journal of Animal and Veterinary Advances, 10, 443-460. https://doi.org/10.3923/ajava.2015.443.460
[7]
Gupta, R., et al. (2010) Anti-Tuberculosis Activity of Selected Medicinal Plants against Multi-Drug Resistant Mycobacterium tuberculosis Isolates. Indian Journal of Medical Research, 131, 809.
[8]
Hiremath, V. and Taranath, T. (2013) Indigenous Traditional Knowledge on Tree Species Survey of Jogimatti Forest, Chitradurga District, Karnataka, India. The Journal of Ethnobiology and Traditional Medicine, 118, 222-227.
[9]
Gupta, V.K., et al. (2017) Plants in Our Combating Strategies against Mycobacterium tuberculosis: Progress Made and Obstacles Met. Pharmaceutical Biology, 55, 1536-1544. https://doi.org/10.1080/13880209.2017.1309440
[10]
World Health Organization (2019) WHO Global Report on Traditional and Complementary Medicine 2019. World Health Organization, Geneva.
[11]
Patwardhan, B. (2005) Ethnopharmacology and Drug Discovery. Journal of Ethnopharmacology, 100, 50-52. https://doi.org/10.1016/j.jep.2005.06.006
[12]
Bunalema, L., et al. (2014) Knowledge on Plants Used Traditionally in the Treatment of Tuberculosis in Uganda. Journal of Ethnopharmacology, 151, 999-1004.
https://doi.org/10.1016/j.jep.2013.12.020
[13]
Buwa, L. and Afolayan, A. (2009) Antimicrobial Activity of Some Medicinal Plants Used for the Treatment of Tuberculosis in the Eastern Cape Province, South Africa. African Journal of Biotechnology, 8, 6683-6687.
[14]
Swami, H.S., et al. (2008) Extraction Technologies for Medicinal and Aromatic Plants. United Nations Industrial Development Organization and the International Centre for Science and High Technology, Trieste, 200, 266.
[15]
Nguta, J.M., et al. (2016) Antimycobacterial and Cytotoxic Activity of Selected Medicinal Plant Extracts. Journal of Ethnopharmacology, 182, 10-15.
https://doi.org/10.1016/j.jep.2016.02.010
[16]
Gemechu, A., et al. (2013) In Vitro Anti-Mycobacterial Activity of Selected Medicinal Plants against Mycobacterium tuberculosis and Mycobacterium bovis Strains. BMC Complementary and Alternative Medicine, 13, Article No. 291.
https://doi.org/10.1186/1472-6882-13-291
[17]
Ramos, D.F., et al. (2008) Investigation of the Antimycobacterial Activity of 36 Plant Extracts from the Brazilian Atlantic Forest. Revista Brasileira de Ciências Farmacêuticas, 44, 669-674. https://doi.org/10.1590/S1516-93322008000400013
[18]
Singh, S., et al. (2012) Rapid Identification and Drug Susceptibility Testing of Mycobacterium tuberculosis: Standard Operating Procedure for Non-Commercial Assays: Part 3: Colorimetric Redox Indicator Assay v1.3.12. Journal of Laboratory Physicians, 4, 120-126. https://doi.org/10.4103/0974-2727.105594
[19]
Palomino, J.-C., et al. (2002) Resazurin Microtiter Assay Plate: Simple and Inexpensive Method for Detection of Drug Resistance in Mycobacterium tuberculosis. Antimicrobial Agents and Chemotherapy, 46, 2720-2722.
https://doi.org/10.1128/AAC.46.8.2720-2722.2002
[20]
Coban, A.Y., et al. (2004) Drug Susceptibility Testing of Mycobacterium tuberculosis by the Broth Microdilution Method with 7H9 Broth. Memórias do Instituto Oswaldo Cruz, 99, 111-113. https://doi.org/10.1590/S0074-02762004000100020
[21]
Bunalema, L., et al. (2017) Potential of Zanthoxylum leprieurii as a Source of Active Compounds against Drug Resistant Mycobacterium tuberculosis. BMC Complementary and Alternative Medicine, 17, Article No. 89.
https://doi.org/10.1186/s12906-017-1602-x
[22]
Oloya, B., et al. (2021) Antimycobacterial Activity of the Extract and Isolated Compounds from the Stem Bark of Zanthoxylum leprieurii Guill. and Perr. Natural Product Communications, 16, No. 8. https://doi.org/10.1177/1934578X211035851
[23]
Tuyiringire, N., et al. (2022) In Vitro Antimycobacterial Activity of Medicinal Plants Lantana camara, Cryptolepis sanguinolenta, and Zanthoxylum Leprieurii. Journal of Clinical Tuberculosis and Other Mycobacterial Diseases, 27, Article ID: 100307.
. https://doi.org/10.1016/j.jctube.2022.100307
[24]
Oloya, B., et al. (2022) Phytochemical Screening, Antimycobacterial Activity and Acute Toxicity of Crude Extracts of Selected Medicinal Plant Species Used Locally in the Treatment of Tuberculosis in Uganda. Tropical Medicine and Health, 50, Article No. 16. https://doi.org/10.1186/s41182-022-00406-7
[25]
Makgatho, M., et al. (2017) Evaluation of the Anti-Mycobacterial, Anti-Oxidative and Anti-Proliferative Activities of Rubia cordifolia Ethanolic Leaf Extract Sub-Fractions in Human Lymphocytes and Neutrophils. African Journal of Traditional, Complementary and Alternative Medicines, 14, 181-187.
https://doi.org/10.21010/ajtcam.v14i5.21
[26]
Komape, N.P.M., et al. (2017) Anti-Mycobacteria Potential and Synergistic Effects of Combined Crude Extracts of Selected Medicinal Plants Used by Bapedi Traditional Healers to Treat Tuberculosis Related Symptoms in Limpopo Province, South Africa. BMC Complementary and Alternative Medicine, 17, Article No. 128.
https://doi.org/10.1186/s12906-016-1521-2
[27]
Nyambuya, T., Mautsa, R. and Mukanganyama, S. (2017) Alkaloid Extracts from Combretum zeyheri Inhibit the Growth of Mycobacterium smegmatis. BMC Complementary and Alternative Medicine, 17, Article No. 124.
https://doi.org/10.1186/s12906-017-1636-0
[28]
Chatha, S.A.S., Anwar, F. and Manzoor, M. (2006) Evaluation of the Antioxidant Activity of Rice Bran Extracts Using Different Antioxidant Assays. Grasas y Aceites, 57, 328-335. https://doi.org/10.3989/gya.2006.v57.i3.56
[29]
Truong, D.-H., et al. (2019) Evaluation of the Use of Different Solvents for Phytochemical Constituents, Antioxidants, and in Vitro Anti-Inflammatory Activities of Severinia buxifolia. Journal of Food Quality, 2019, Article ID: 8178294.
https://doi.org/10.1155/2019/8178294
[30]
Luo, X., et al. (2013) Zanthoxylum capense Constituents with Antimycobacterial Activity against Mycobacterium tuberculosis in Vitro and ex Vivo within Human Macrophages. Journal of Ethnopharmacology, 146, 417-422.
https://doi.org/10.1016/j.jep.2013.01.013
