Evaluation of different solvents on flavonoids extraction efficiency from sweet oranges and ripe and immature Seville oranges

Summary The effects of different ethanol (50%, 80% and 100%) and methanol (50%, 80% and 100%) aqueous solutions on extraction efficiency of flavonoids from sweet orange (SO) peels, ripe bitter orange (RBO) and immature bitter orange (IBO) were investigated. The highest amount of naringin was found in SO peels, compared to RBO and IBO. UHPLC‐HRMS/MS results confirmed the presence of p‐coumaric acid and quinic acid in all the three types of oranges while there were 90.91% and 20% possibilities for detecting caffeic acid in RBO and SO, respectively. The probabilities of detecting naringenin from IBO, RBO and SO were 100%, 63.64% and 40%, respectively. The highest neohesperidin and naringin amounts were obtained in RBO. Using 80% methanol was recommended for extracting flavonoids from SO to obtain the highest Soxhlet and precipitation yields whereas 100% ethanol was the most suitable solvent to extract flavonoids from RBO and IBO. The procedure of flavonoids extraction from waste orange peels.