Phenolic contents and antiradical capacity of vegetable oil from Pistacia lentiscus (L)

Oxidative stress has been shown to be involved in the development of different pathologies. Antioxidant can be used for preventing or delaying oxidation. Natural products are rich in molecules capable of such activity. In the present work, the antiradical capacity of vegetable oil of Pistacia lentiscus L. (VOPL) was compared to the activity obtained with synthetic antioxidants. We first determined total phenolic content in VOPL by the Folin- Ciocalteau’s method, total flavonoid content was assessed by a colorimetric method using quercetin as standard flavonoid, whereas antioxidant activity of the extracts was determined spectrophotometrically using 2,2-diphenyl-1-picrylhydrazyl (DPPH ) and evaluated following the kinetics of the DPPH reduction. The total phenol content was 122.72±1.16 mg GAE/g of extract and the flavonoid content was 18.41±0.43 mg QE/g. The saponification and acid index of PLVO are also determined in the selected vegetable oil using potassium hydroxide (KOH). VOPL had higher antioxidant activity (IC_50=37.38 μg/ml) than ascorbic acid (IC_50=27.20 μg/ml). The parameter IC_50 and its time equivalent TIC50 have an influence on the antiradical capacity of vegetable oil. The antiradical efficiency (AE) of Pistacia vegetable oil and ascorbic acid was respectively 7.23 and 20.40 mg/ml.mn. This parameter was reported to be a powerful parameter to select antioxidants compared to IC_50. Acid and saponification index were respectively 5.5 and 140 giving an acidity value of 4% for VOPL. This study has revealed that P. lentiscus is a considerable source of natural antioxidants.