Assessment of the efficacy of plant-derived essential oils against Mycobacterium tuberculosis: A systematic review and meta-analysis

Mycobacterium tuberculosis (MTB), the causative agent of tuberculosis (TB), remains a major global health challenge, exacerbated by the rise of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains. Limitations in current antibiotic therapies have intensified interest in alternative antimicrobials, including plant-derived phytochemicals. Essential oils (EOs), with their complex chemical composition and long-standing traditional use, represent promising candidates for novel anti-TB agents. This study conducted a systematic review and meta-analysis to evaluate the in vitro antimycobacterial activity of plant-derived EOs. Following PRISMA guidelines, four major databases, Scopus, MEDLINE Central/PubMed, Embase, and Web of Science, were searched through May 31, 2025, and 31 eligible studies were included after screening and quality assessment. Descriptive and comparative analyses of minimum inhibitory concentrations (MICs) were performed using R software. The results revealed substantial variability in EO efficacy across plant species and geographic origins. The most potent activity was observed in Euclea sp. and Croton sp., which showed exceptionally low MICs of 1 μg/mL and 4.88 μg/mL, respectively. In contrast, EOs from Dichrostachys cinerea , Dorstenia elliptica , Imperata cylindrica , Mondia whitei , Pentadiplandra brazzeana , and Tetrapleura tetraptera exhibited weaker effects, with MICs up to 2048 μg/mL. Plant anatomical sources also influenced activity, with leaves and stems showing higher efficacy than roots and fruits. Overall, these findings highlight the therapeutic potential of specific EOs as adjunct or alternative treatments for DR-TB. Further studies involving compound standardization, and in vivo validation are necessary to support their development into clinically applicable anti-TB agents. • A global systematic review and meta-analysis of 31 studies on EOs against MTB, including MDR/XDR strains. • The most potent activity was observed in Euclea sp. and Croton sp., which showed exceptionally low MICs of 1 μg/mL and 4.88 μg/mL, respectively. • Dichrostachys cinerea , Dorstenia elliptica , Imperata cylindrica , Mondia whitei , Pentadiplandra brazzeana , and Tetrapleura tetraptera showed the minimum substantial antimycobacterial effects (MIC ≤ 2048 μg/ml). • Piper was the most studied genus, with consistent anti-MTB activity. • Asian plant EOs had the lowest average MICs, indicating high potency. • Roots and fruits exhibited more potent antimicrobial activity than leaves. • Findings support further development of EO-based therapies for drug-resistant TB.