A novel extraction method for β-carotene and other carotenoids in fruit juices using air-assisted, low-density solvent-based liquid-liquid microextraction and solidified floating organic droplets

Abstract

Green extraction using air-assisted, low-density solvent-based liquid-liquid microextraction and solidified floating organic droplets (AA-LDS-LLME-SFOD) prior to spectrophotometry was successfully applied for quantitation of carotenoids in fruit juices. Under optimal conditions, β-carotene could be quantified with a linear response up to a concentration of 60 μg mL(-1). The procedure was performed in a microcentrifuge tube with 40 μL of 1-dodecanol as the extraction solvent and a 1.0 mL juice sample containing 8% NaCl under seven extraction cycles of air pumping by syringe. This method was validated based on linearity (0.2-30 μg mL(-1), R(2) 0.998), limit of detection (0.04 μg mL(-1)) and limit of quantification (0.13 μg mL(-1)). The precision, expressed as the relative standard deviation (RSD) of the calibration curve slope (n=12), for inter-day and intra-day analysis was 4.85% and 7.92%, respectively. Recovery of β-carotene was in the range of 93.6-101.5%. The newly proposed method is simple, rapid and environmentally friendly, particularly as a useful screening test for food analysis.

Keywords: 1-Dodecanol (PubChem CID: 8193); 1-Undecanol (PubChem CID: 8184); 2-Dodecanol (PubChem CID: 25045); Air-assisted; Aluminium chloride (PubChem CID: 24012); Calcium chloride (PubChem CID: 5284359); Disodium hydrogen phosphate (PubChem CID: 24203); Fruit juice; Hydrochloric acid (PubChem CID: 313); Liquid–liquid microextraction; Low-density solvent; Sodium chloride (PubChem CID: 5234); Sodium hydroxide (PubChem CID: 313); Sodium nitrate (PubChem CID: 24268); Sodium sulphate (PubChem CID: 24436); Solidified floating organic droplets; Tetrahydrofuran (PubChem CID: 8028); β-Carotene; β-Carotene (PubChem CID: 5280489).