Antioxidant and Anti-Colorectal Cancer Properties in Methanolic Extract of Mangrove-Derived Schizochytrium sp.

Abstract

This work studied the antioxidant and anti-colorectal cancer properties of a potential strain of thraustochytrids, Schizochytrium sp. (SMKK1), isolated from mangrove leaf litter. The biomass was extracted with methanol and screened for antioxidant activity using six different assays. The extract exhibited the highest total antioxidant activity (87.37 ± 1.22%) and the lowest nitric oxide radical (75.12 ± 2.22%), and the activity increased with the concentration of the extract. The methanolic extract was further tested for in vitro cytotoxicity on the colon cancer cell line (HT29). The extract was also analyzed for polyunsaturated fatty acids using GC-MS. The five predominant HTVS-based compounds, viz., arachidonic acid, linolenic acid (alpha-linolenic acid and gamma-linolenic acid), eicosapentaenoic acid, and docosahexaenoic acid, were identified in the extract, and these were tested against the colon cancer protein IGF binding (IGF-1) using the in silico docking method. The results revealed that all the five compounds were capable of destroying the colon oncoprotein responsible for anti-colon carcinogen, based on activation energy and also good hydrogen bond interaction against IGF binding proteins. Of the compounds, docosahexaenoic acid was the most effective, having a docking score of −10.8 Kcal/mol. All the five fatty acids passed the ADMET test and were hence accepted for further clinical trials towards the development of anticancer drugs.