Antioxidant Activity of Fungus Comb Extracts Isolated from Indo-Malayan Termite Macrotermes gilvus Hagen (Isoptera: Termitidae)

Indonesian termites are one of the wealthiest biological resources considering their very high species diversity (300 species) and extensive geographical distribution in the Indonesian mainland. However, its potential as a source of bioactive compounds has not been fully explored. One of the endemic termite sub-families of Indonesian, Macrotermitinae (Isoptera: Termitidae), has a food source in the form of fungal nodules that grow and spread in a particular structure in the termite nest that is shaped like a mammalian brain called a fungus comb, which likely serves as a source of bioactive compounds. This study aims to analyze the potential of fungus comb from an Indonesian Macrotermitinae sub-family species as a source of antioxidants. Antioxidant activity was tested on four different extracts of fungus comb (EFC), namely hexane extract, ethyl acetate extract, methanol extract and water extract, using DPPH• (1,1-diphenyl-2-picrylhydrazyl) and ABTS•+ (2,2′-azino-di-[3-ethylbenzthiazolinesulphonate]) radicals. The results showed that the highest antioxidant activity was found in methanol extract, followed by ethyl acetate extract with IC₅₀ values of 0.6 mg/mL and 0.75 mg/mL, respectively. TEAC (Trolox equivalent antioxidant capacity) analysis confirmed the high antioxidant activity of methanol extract.