Potential antioxidant and antiradical agents from Allium ascalonicum: Superoxide dismutase and density functional theory in silico studies

Abstract

Antioxidants are compounds that can inhibit excessive free radical reactions in the body. Excessive free radicals can cause system imbalances in the body which can trigger oxidative stress and cause serious illness. The limitations of antioxidants in the body can be overcome by consuming safe natural additional antioxidants that can be obtained from natural products. Isolating compounds of Allium ascalonicum leaves as antioxidant and antiradical agents in inhibiting excessive free radicals by in vitro and in silico. The extracted compounds were purified by column chromatography. The compounds obtained were then characterized using ultraviolet, infrared, NMR, and mass spectrometry. Determination of antioxidant activity was carried out by in vitro using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the non-enzymatic superoxide dismutase (SOD) methods. The in silico study used the density functional theory (DFT) calculation method with global descriptive parameters (GDP), donor acceptor map (DAM), and frontier molecular orbitals (FMO) analysis. Three compounds have been isolated, of which compound 1 is a new compound. In the DPPH method, compound 1 has more strong antioxidant activity than others, as well as in the non-enzymatic SOD method. Whereas, in the DFT calculation shows that compound 1 has the best reactivity and stability between other compounds and was categorized as the best antiradical. Compound 1 has the highest antioxidant activity compared to the other compounds by in vitro both the DPPH and non-enzymatic SOD methods. In silico, compound 1 has the potential as the best antiradical.