FTIR-METABOLOMICS TO CORRELATE SORGHUM’S CHEMICAL PROFILE AND HCT-116 CYTOTOXICITY CHANGES DURING RICE-ANALOGUE PRODUCTION

Rice-analogue (RA) made from sorghum (Sorghum bicolor L. Moench) is recently popular in Indonesia due to its potential as an alternative staple food besides rice. Sorghum has many phytochemi-cals with various functional properties including those correlating with anticancer activity. The RA produc-tion involves several steps; i.e. polishing, milling, mixing, extruding, and oven drying. This study used FTIR based metabolomics to identify whether these steps affect sorghum phytochemicals composition and its cytotoxicity against HCT-116 cell lines in-vitro. It was discovered that the cytotoxic of sorghum was rela-tively stable during the process. The RA final product (oven dried RA) showed higher activity (90.85%) as compared to other samples taken from previous steps (2000 ppm dose). The correlation between the FTIR profile and cytotoxic activity of RA was analyzed using one of the multivariate data analysis method namely orthogonal projection to the least square (OPLS). By comparing the OPLS data with FTIR data of compounds reported to be found in sorghum, it is shown that typical FTIR patterns for the phenolic com-pounds particularly ferulic acids, p-coumaric acid, and procyanidins, as well as phytosterols, were highly correlated with the RA’s cytotoxic activity. The signals were found to be dominant in the most active sample (oven dried RA). It can be concluded that sorghum phytochemicals responsible for its cytotoxic activity were not affected by the processing steps, therefore RA is potential to be promoted as an alterna-tive functional staple food in Indonesia.