A Food-Grade Approach to Isolate Crocetin from Saffron (Crocus sativus L.) Extracts

The present study proposes a food-grade approach for the isolation of the valuable apocarotenoid crocetin (CRT) from saffron extracts rich in crocetin esters. Its isolation involved optimization of saffron: solvent ratio (w/v) using response surface methodology (RSM) and encapsulation in deoxycholic acid (DCA) to form an inclusion complex (CRT-DCA). RP-HPLC-DAD was the major tool to monitor the effectiveness of the extraction process. The optimum ratio found (1: 180w/v) spares the precious starting material (yield 62.7 +/- 2.5 g dry extract/100 g dry stigmas, CRT purity 98 %) and reduces the cost of the process. The successful formation of the complex was confirmed by an array of techniques such as Fourier transform-infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and wide angle X-ray diffraction (WAXD). Encapsulation efficiency (%) measured directly and indirectly was found to be satisfactory.