Effect of extraction solvent on total phenolic content, total flavonoid content, and antioxidant activities of Algerian pomace olive oil

The present study was aimed to investigate the effect of extraction solvent on oil yield, phenolic, flavonoid content and antioxidant activities. For this purpose, two-phases pomace olive were subjected to solvent extraction using solvents of different polarities (Acetone, Hexane, methanol, Petroleum ether and mixture of Chloroform/Methanol). The phenolic compound in pomace olive oil were extracted by methanol-water. The Folin-Ciocalteu and Aluminium trichloride (AlCl3) method was employed to calculate the total phenolic and flavonoid content respectively, while antioxidant capacity was assessed with DPPH, beta-carotene/linoleic acid and FRAP. The oil content of pomace olive obtained after extraction with solvents of different polarities was in the range of 7.55 - 16.92 g/100 g. The best oil yield (16.92%) was obtained with the mixture Chloroform/Methanol 25/75. POO8 (extracted with pure Methanol) has the highest content of total phenolic and flavonoid which was 136.78 mg GAE/100g oil and 27.66 mg QE/100g oil, respectively. On the other hand, POO7 (extracted with mixture Chloroform/Methanol 25/75) exhibited the highest radical DPPH scavenging power (71.40%), and POO5 (extracted with mixture Chloroform/Methanol 75/25) presented the highest bleaching rate of beta-carotene (83.84%). High positive significant correlation (r=0.880, p<0.01) was found between total phenolic content and FRAP. However, no significant correlation was found between total flavonoid content and beta-carotene bleaching. The results obtained demonstrated that pomace olive oil could have to be used as natural a potential source of bioactive compounds (antioxidants). (c) All Rights Reserved