Phytochemical, Cytotoxicity, and Antimycobacterial Activity Evaluation of Extracts and Compounds from the Stem Bark of Albizia coriaria Welw ex. Oliver

Samuel Baker Obakiro; Ambrose Kiprop; Isaac K'owino; Moses Andima; Richard Oriko Owor; Robi Chacha; Elizabeth Kigondu

doi:10.1155/2022/7148511

Phytochemical, Cytotoxicity, and Antimycobacterial Activity Evaluation of Extracts and Compounds from the Stem Bark of Albizia coriaria Welw ex. Oliver

Evid Based Complement Alternat Med. 2022 Jan 22:2022:7148511. doi: 10.1155/2022/7148511. eCollection 2022.

Authors

Samuel Baker Obakiro^{1

2

3}, Ambrose Kiprop^{2

3}, Isaac K'owino^{3

4}, Moses Andima⁵, Richard Oriko Owor⁵, Robi Chacha⁶, Elizabeth Kigondu⁷

Affiliations

¹ Department of Pharmacology and Therapeutics, Faculty of Health Sciences, Busitema University, P.O. Box 1460, Mbale, Uganda.
² Department of Chemistry and Biochemistry, School of Sciences and Aerospace Studies, Moi University, P.O. Box 3900-30100, Eldoret, Kenya.
³ Africa Centre of Excellence II in Phytochemicals, Textile and Renewable Energy (ACE II PTRE), Moi University, P.O. Box 3900-30100, Eldoret, Kenya.
⁴ Department of Pure and Applied Chemistry, Faculty of Science, Masinde-Muliro University of Science and Technology, P.O. Box 190-50100, Kakamega, Kenya.
⁵ Department of Chemistry, Faculty of Science Education, Busitema University, P.O Box 236, Tororo, Uganda.
⁶ Centre of Respiratory Disease Research, Kenya Medical Research Institute, P.O. Box 54840-00200, Nairobi, Kenya.
⁷ Centre of Traditional Medicine and Drug Research, Kenya Medical Research Institute, P.O. Box 54840-00200, Nairobi, Kenya.

Abstract

Background: Albizia coriaria Welw ex. Oliver (Fabaceae) is one of the plants used by herbalists in the East Africa community to prepare herbal remedies for the management of symptoms of TB. Despite its widespread use, the antimycobacterial activity of this plant was uninvestigated and there was contradicting information regarding its cytotoxicity.

Methods: Cytotoxicity (MTT), antimycobacterial activity (MABA), and phytochemical screening were conducted on crude extracts (hexane, chloroform, acetone, and methanol) of the stem bark of A. coriaria. Gas chromatography-mass spectrometry (GC-MS) followed by Fourier transform infrared (FTIR) spectroscopy was carried out on the acetone and methanol extracts. The binding affinities and descriptors of pharmacokinetics and toxicity of the identified compounds were predicted using computational modelling software.

Results: The cytotoxic concentrations of all extracts were greater than 1000 μg/mL. The minimum inhibitory concentration of both the acetone and methanol extracts was 1250.0 ± 0.0 μg/mL against M. smegmatis, whereas that against M. tuberculosis was 937.0 ± 442.0 μg/mL and 2500.0 ± 0.0 μg/mL, respectively. Hexane and chloroform extracts were not active against both strains. Alkaloids, triterpenes, flavonoids, tannins, and saponins were the predominant phytochemicals present. GC-MS analysis revealed twenty-eight and nineteen compounds in acetone and methanol extracts, respectively. Among these was hydroquinone, which was previously reported to possess antimycobacterial activity. Seven compounds identified through GC-MS analysis had better binding affinities for the mycobacterial ATPase and polyketide synthase-13 than isoniazid and rifampicin. These compounds also showed variable but promising pharmacokinetic properties with minimum toxicity.

Conclusion: There are phytochemicals in A. coriaria stem bark with potential antimycobacterial activity and acceptable cytotoxicity, which can be further explored and optimized for the development of novel antitubercular drugs.