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The world is currently alarmed by the term “global boiling” due to the drastic rise in average temperatures worldwide. Methane emissions are a significant contributor to this phenomenon.
The Global Monitoring Laboratory reports that methane emissions have increased since 1980, from 1,620 ppb to 1,933.46 ppb in October 2023. These emissions can raise global temperatures 28 times more than CO2.
Approximately 20-25% of total methane emissions come from livestock activities, specifically enteric fermentation in livestock rumens. This process produces methane gas that is then expelled through feces and belching.
This issue has caught the attention of five students from Universitas Gadjah Mada (UGM), who have researched utilizing seaweed (Gracilaria sp.) and noni fruit as feed additives. These additives are expected to modify the rumen environment to reduce methane production in livestock.
The research team comprises Ahmad Rizal Riswanda Danuartha (Animal Science and Industry, 2022), Aqidatul Izza (Aquatic Resource Management, 2022), Dinda Rahmasari (Animal Science and Industry, 2022), Elsia Manik (Chemistry, 2023), and Tanaya Bagus Priya Waskita (Animal Science and Industry, 2022).
The project, part of the Student Creativity Program in Exact Science Research (PKM-RE), is funded by the Ministry of Education, Culture, Research, and Technology and supervised by lecturer Moh Sofiul Anam.
Macroalgae, commonly known as seaweed, contains various secondary metabolites that can reduce methane emissions from livestock.
“We chose the Gracilaria sp. type of macroalgae because it contains tannins, saponins, alkaloids, and flavonoids, which are believed to modify the fermentation process in the livestock rumen by inhibiting the activity of methanogenic bacteria. This reduces methane production from the livestock sector without disrupting the animals’ digestion,” said Ahmad Danuartha, the research team leader, on Tuesday (Jul. 23).
Danuartha added that the feed additive innovation utilizes noni fruit, which has minimal use in the livestock sector, in addition to seaweed.
“In Jogja alone, noni fruit production reached 163,532 kg in 2021. However, this fruit is rarely used, even though it contains around 100 secondary metabolites, including tannins, polyphenols, flavonoids, and other compounds. These compounds are believed to modify the fermentation process in the rumen, similar to Gracilaria sp.,” he explained.
The research samples were sourced from local resources in the Yogyakarta Special Region.
“We sourced the seaweed from Sepanjang Beach, Gunungkidul, and the fresh noni fruit from Berbah, Sleman. The seaweed was air-dried for two weeks, while the noni fruit was oven-dried at 55°C for three days. The samples were then extracted and dried using freeze-drying to form granules,” elaborated Danuartha.
Another team member, Elsia Manik, mentioned that the macroalgae and noni fruit granules would be tested for effectiveness through in vitro tests at the Animal Feed Technology Laboratory and the Organic Chemistry Laboratory at UGM.
“For the in vitro tests, we used rumen fluid from fistulated Bali cattle, and the gas produced will be analyzed for methane content. If the gas test results show lower methane levels than the standard, the feed additive innovation will have proven effective in reducing methane emissions from rumen fermentation,” explained Manik.
The addition of macroalgae and Morinda citrifolia extract at dosages of T2 (3% macroalgae + 3% Morinda citrifolia) and T3 (2% macroalgae + 4% Morinda citrifolia) showed an increase in dry matter digestibility of 5.78% and 4.73%.
Furthermore, methane production at the 24th hour significantly decreased at doses T1 (4% macroalgae + 2% Morinda citrifolia) and T3 (2% macroalgae + 4% Morinda citrifolia) by 14.04% and 33.1%, respectively.
At the 48th hour, methane production decreased by 27.78%. Initially, the energy in the feed was not optimally absorbed as it was used for methane production.
“We hope this innovation can help reduce methane emissions from the livestock sector and gradually address climate change,” said Manik.
Source: UGM Seaweed and Noni Fruit Team
Editor: Satria