Co-extraction of turmeric (Curcuma longa L.) and dried coconut shreds by supercritical fluid extraction (SFE): Chemical and bioactivity profile

This work emphasized on the co-extraction of turmeric (Curcuma longa L.) and dried coconut shreds (Cocos nucifera L.) by supercritical fluid extraction (SFE), a green extraction technique, vis-à-vis the conventional solvent extraction using n-hexane. The optimized parameters of co-extraction using SFE through central composite design (CCD) with response surface methodology (RSM) were found to be 350 bar/65 °C/20 min having a yield of 45 mg/g, and a total curcuminoid (curcumin, desmethoxycurcumin, and bisdemethoxycurcumin) content of 723 μg/g. The yield of co-extract after 16 h of conventional soxhlet extraction using n-hexane was 42 mg/g and total curcuminoids in the co-extract were 339 μg/g. The SFE co-extracts showed 345 μg AAE/mg sample DPPH radical scavenging activity, 394 μg AAE/mg sample ABTS radical scavenging activity, 210 μM FeSO4 7H2O/mg sample ferric reducing antioxidant power (FRAP), 89% anti-inflammatory activity as compared to the standard drug, and bactericidal effects against Bacillus cereus, Escherichia coli, and Salmonella typhi. The SFE co-extracts showed promising in vitro anti-cancerous activities in MCF7 (breast cancer) and CaCO2 cell lines.