Enzymatic assay of coffee peel and papaya peel waste eco enzyme

¹ Biotechnology Study Program, Department of Applied Science, Faculty of Mathematics and Natural Science, Universitas Negeri Malang, Malang, Indonesia
² Center of Health and Food, Institute of Research and Community Services, Universitas Negeri Malang, Malang, Indonesia
³ Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Negeri Malang, Malang, Indonesia

^* Corresponding author : norman.haryono.fmipa@um.ac.id

Abstract

Coffee is one of Indonesia’s main products with the consumption rate reach 10 million tons in 2020-2021 globally. This high productivity raises the problem of coffee peel waste which has been utilized as animal feed or fertilizer. Eco enzyme, a complex solution formed by the fermentation of organic waste, sugar, and water can be used as an alternative for utilizing coffee peel waste. This research was conducted to test the enzymatic activity of eco enzyme from coffee peel and papaya peel that fermented for 2, 3, and 4 months. The enzymes tested were protease, amylase, and lipase using selective agar media 1% skim milk, 1% starch, and 5% olive oil respectively. The results obtained was the eco enzyme contains protease as indicated by the formation of a clear zone around the sample. Meanwhile, the negative results of amylase activity were thought to be due to the presence of caffeine from coffee peel and certain compounds from papaya peel which can inhibit α-amylase activity. The results of the lipase activity test could not be observed due to the large range of pH value of methyl red so that the reddish zone was not formed by the hydrolyzation of triglycerides into fatty acids that cause the pH value decrease.