Purification of ultrasonic assisted extracted chlorogenic acid from Citrullus lanatus rind using macroporous adsorption resin (MPAR)

Recycling food waste to extract valuable bioactive compounds (BAC) offers a groundbreaking solution to mitigate environmental challenges. The isolation and purification of BAC from food waste are getting more attention to maintain environmental sustainability. The therapeutic potential of these compounds highlights the need for innovative approaches to extracting and purifying them from by-products. In this context, the chlorogenic (CG) acid is extracted from watermelon <i>(Citrullus lanatus)</i> rind (WMR) using ultrasound-assisted extraction (USAE) technique and purified using the macroporous adsorption resin (MPAR) method. The extraction and purification were carried out with water, 70 % <i>v</i>/v ethanol/water (70 % Et), and 90 % v/v ethanol/water (90 %-Et) solvent to analyze the impact of solvent on extraction efficiency, purity, and recovery. The extracted CG acid was qualitatively analyzed via UV spectrometry and HPLC and underwent FESEM analysis while purified CG acid was characterized via FTIR and thermal analysis. The implementation of the MPAR method notably increased the yield to 4.6 mg/g of raw material using solvents comprising 90 % ethanol than water and 70 % ethanol. The recovery of CG acid significantly escalated to 88 %, enhancing the purity percentage from an initial range of 70-94 %.