COMPARATIVE STUDY OF CONVENTIONAL SOLVENT AND SUPERCRITICAL FLUID EXTRACTS OF TURMERIC USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

摘要

Dietary intrusions emphasize on the dynamic facets of phytonutrients as they exert positive health impact against various metabolic disorders. Amongst, turmeric bioactive ingredients are well known for its strong antioxidant potential. Purposely, turmeric nutraceutic i.e. curcumin was isolated followed by quantification using high performance liquid chromatography (HPLC). For optimal extraction of curcumin, three conventional solvents (aqueous ethanol, -methanol & -acetone), each at 35, 50 and 65 min and supercritical carbon dioxide at varying time intervals; 50, 100 & 150 min were employed. The resultant conventional extracts were tested for total phenolic contents (TPCs), 2,2-diphenyl 1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)/ABTS, ferric reducing antioxidant power (FRAP) and iron chelating assays. Aqueous ethanolic extract showed best results at 65 min; TPC 917.06 +/- 10.08 mg GAE/100g, DPPH 65.12 +/- 2.87%, FRAP 194.47 +/- 8.03 mu M Fe2+/g, ABTS 163.14 +/- 6.12 mu M Trolox/g and iron chelation activity 66.92 +/- 2.95%. Furthermore, the best selected conventional solvents and supercritical fluid extracts were quantified via HPLC system. Results revealed highest curcumin yield in supercritical fluid extracts i.e. 52.41 +/- 2.38 mg/g at 150 min followed by 46.03 +/- 2.15 and 33.62 +/- 1.24 mg/g at 100 & 50 min, respectively. While, conventional ethanolic, methanolic and acetonic extracts showed values as 31.48 +/- 1.35, 28.75 +/- 1.09 and 23.19 +/- 1.12 mg/g, respectively.