Microencapsulation of Mitragyna leaf extracts to be used as a bioactive compound source to enhance in vitro fermentation characteristics and microbial dynamics

Abstract

Objective: <i>Mitragyna speciosa</i> Korth is traditionally used in Thailand. They have a high level of antioxidant capacities and bioactive compounds, the potential to modulate rumen fermentation and decrease methane production. The aim of the study was to investigate the different levels of microencapsulated-<i>Mitragyna</i> leaves extracts (MMLE) supplementation on nutrient degradability, rumen ecology, microbial dynamics, and methane production in an <i>in vitro</i> study.Methods: A completely randomized design was used to assign the experimental treatments, MMLE was supplemented at 0%, 4%, 6%, and 8% of the total dry matter (DM) substrate.Results: The addition of MMLE significantly increased <i>in vitro</i> dry matter degradability both at 12, 24, and 48 h, while ammonia-nitrogen (NH₃-N) concentration was improved with MMLE supplementation. The MMLE had the greatest propionate and total volatile fatty acid production when added with 6% of total DM substrate, while decreased the methane production (12, 24, and 48 h). Furthermore, the microbial population of cellulolytic bacteria and <i>Butyrivibrio fibrisolvens</i> were increased, whilst <i>Methanobacteriales</i> was decreased with MMLE feeding.Conclusion: The results indicated that MMLE could be a potential alternative plant-based bioactive compound supplement to be used as ruminant feed additives.