HighPerformanceLiquid Chromatography of antioxidant activity of seeds some varieties of prickly pear (Opuntia ficus-indica L.) from the Sidi-Fredj Souk Ahras Algeria

Abstract

The study was conducted on seeds of three varieties of Opuntia ficus-indica (O. ficus-indica), harvested from different regions of Souk Ahras in north-East of Algeria (Sidi-Fredj, Taoura and Drea). The analysis consisted of antioxidants extraction, following the solid-liquid extraction with ethanol 40% (v/v), their quantification and determination of their antioxidant activity by two methods (reducing power and DPPH (2-2 diphenyl 1-picryl hydrazyl) Test). Results show that total phenolic content (TPC) ranged from 71,01to 90,79mg GAE (Gallic Acid Equivalent)/100g Extract. The Sidi-Fredj variety has the best rate followed by the Taoura and Drea ones. Concerning, flavonoids and tannins, the Taoura variety contains higher concentrations corresponding to 2.67 mg QE (Quercetin equivalent)/100g and 6.60mg CE (Cyanidin equivalent)/100g. Activities of extracts of three varieties show similar performance; the EC50 for the reduction of ferric iron 0.05g/mL for all extracts, whereas the EA is more important in Sidi-Fredj and Drea seeds extracts. Regarding the scavenging of DPPH, Drea and Sidi-Fredj varieties show the highest capacity equals to 0.20g/mL. Linear correlations between the different studied activities and some antioxidants (flavonoids, tannins) rates were noticed, indicating their participation in the obtained effect. Analysis of the oil by HPLC revealed the presence of phenolic compounds including gallic acid and a form of vitamin E (α-tocophérol), capable of expressing biological activities; Antioxidants and vitamins. GC (Gas Chromatography) analysis showed that prickly pear oil was a major source of essential fatty acids (C18:2 and C18:3). The anti-free radical activity of the seed was evaluated through a DPPH chemical test. The results obtained show a hight reducing activity of our extract.