Innovative Strategies for Methane Mitigation: The Role of Durian Seed Nanoemulsions (DSN) in In vitro Studies

The livestock sector, particularly ruminants, contributes to global warming through methane emissions, which are a significant source of greenhouse gases. These emissions also have a reciprocal impact on the ruminant sector, as climate change and unstable weather conditions affect the availability and quality of forage for livestock. This research, conducted using the Theodorou method on an in vitro scale with rumen fluid from cattle obtained via fistula, aims to explore the potential of Durio zibethinus seed waste in the form of nanoemulsion preparations for reducing methane gas emissions. Qualitative analyses confirmed the presence of tannins, flavonoids, alkaloids, saponins, and steroids in the Durian Seed Nanoemulsion (DSN). Quantitative assessments revealed flavonoid content at 4.2 mg RE/g dry weight, total phenolic content at 9.1 mg GAE/g dry weight, and total tannin content of 7.6%, with 4.4% as condensed tannins and 3.2% as hydrolysable tannins. In vitro gas production experiments showed that while the incor-poration of DSN did not significantly affect gas production kinetics from soluble or potentially degradable feed frac-tions (p > 0.05), methane production was significantly reduced with increasing DSN levels (p < 0.05). These findings highlight DSN’s potential as an effective additive for mitigating methane emissions in ruminant feed, suggesting that the active compounds in Durio zibethinus seed could play a key role in promoting more sustainable livestock practices.