Melinjo (Gnetum Gnemon) Seed Protein Activity Against pBSKS DNA Cleavage and Its Cytotoxicity in T47D and 4T1 Cells

Abstract

The plant protein of melinjo (Gnetum gnemon) in seeds is known to have antioxidant properties. Apart from being an antioxidant, melinjo seed protein also has the potential to be developed as an anticancer compound. One of the potential anticancer compounds has been screened based on supercoiled DNA cleavage activity (pBSKS). The purpose of this study was to determine the activity of the protein fraction isolated with DEAE and BUTYL matrices against supercoiled DNA cleavage of pBSKS. Supercoiled DNA cleavage test activity of pBSKS was determined using the electrophoresis method and visualized with a UV transilluminator at a wavelength of 312 nm. The cytotoxic activity of melinjo seeds was tested through the MTT assay method and was read on an ELISA reader with a wavelength of 550 and 595 nm seen from the IC50 value. The protein fraction of melinjo seeds isolated with DEAE and BUTYL matrices had concentrations of 470.1 and 81.02 g/mL, respectively. The visualization results showed that the DEAE and BUTYL protein fractions resulted in depletion of supercoiled DNA bands of pBSKS. The concentration of active protein in the melinjo seeds fractionated using the DEAE-650M matrix was higher than that of the BUTYL-650M matrix. In this study, after several cytotoxic tests were carried out, various results were obtained. The activity of protein isolates from melinjo seeds fractionated using DEAE-650M and BUTYL-650M against 4T1 and T47D cells could be categorized as non-toxic because the IC50 value was > 1000 g/mL and the average percentage of viable cells was more than 50%, except for the seed protein fraction. Melinjo fractionated using DEAE-650M against T47D cells which had an IC50 value of 127.62 g/mL could be categorized as quite active and cytotoxic. Keywords: Gnetum gnemon L., protein isolation, ribosome-inactivating proteins (RIPs), DNA cleavage, cytotoxic, T47D, 4T1