Evaluation of Anti-Methanogenic Compound and Phytogenic Extract of Moringa oleifera on Ruminal Methane Production

Abstract

Livestock are significant contributors to methane (CH4) emissions, a potent greenhouse gas. The aim of research was to investigate the potential of Moringa oleifera to reduce methane emissions from ruminants. This research was conducted in three stages, the study includes a meta-analysis, isolation and characterization of Moringa oleifera compounds, and an in-silico analysis. A comprehensive literature search identified 24 relevant studies. The meta-analysis revealed that Moringa oleifera supplementation significantly improves dry matter digestibility (DMD) and organic matter digestibility (OMD) while reducing methane emissions (p<0.01) without adversely affected (p>0.05) ruminal fermentation parameters. The different part of Moringa oleifera plant demonstrated varied effect: Moringa leaves reduced ammonia levels and increased volatile fatty acids, while Moringa seeds had a significantly greater effect on methane reduction compared to Moringa leaves and pods, by lowering acetate and propionate ratio. Moringa seeds has selected as a promising source for extraction and isolation of anti-methanogenic compound. Using high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR), 2,3,6-trihydroxybenzaldehyde was isolated and identified from Moringa seeds. Phytochemicals from Moringa oleifera were screened and compared with isolated compound, and anti-methanogenic compound such as 3-nitrooxypropanol and native ligands from MCR enzyme (Coenzyme M and Coenzyme B) through molecular docking analysis. The selected phytochemicals such as Niazinin, Niazimicin A, Pterygospermin, Niazirinin, 4-[(4'-O-Acetyl-alpha-L-rhamnosyloxy)benzyl]isothiocyanate, Niazimin, Niazicinin A exhibit promising drug-likeness based on Lipinski’s rules of five and Absorption, Distribution, Metabolism, Excretion and Toxicology (ADME-Tox) properties. The in-silico study demonstrated that 2,3,6 trihydroxybenzaldehyde has a lower binding affinity to the Methyl Coenzyme M Reductase (MCR) enzyme compared to pterygospermin. Pterygospermin exhibited the highest binding interaction with the enzyme's active site include Pi-sulfur (Phe443), Pi-alkyl (Val482, Leu320, Met324), Pi-Pi stacked (Phe330), and van der Waals interactions (Tyr333, Ser325), effectively inhibiting MCR, which is responsible for methane production in ruminants. These findings suggest that Moringa oleifera could serve as a phytogenic feed additive to mitigate methane emissions.