Contribution to Phytotherapy Valorization of the Seed of Avocado, <i>Persea Americana</i>

Plants represent an immense storehouse of biomolecules endowed with diverse biological properties. This study was carried out to analyze the phytochemical composition and evaluate the free radical scavenging and antioxidant activities of Persea americana seed. The dried avocado pit powder was first delipidated with hexane and the residue was successively extracted by maceration with ethanol-water mixture (50% -50%: v/v), and ethanol. Qualitative phytochemical analyses were carried out on the two extracts; and quantitative assays, to assess total polyphenol, flavonoid and condensed tannin contents. The free radical scavenging and antioxidant activities of the extracts were assessed. The results had revealed the presence of polyphenols, alkaloids, flavonoids, saponosides, anthocyanins, anthraquinones, steroids, cardiac glycosides, and condensed tannins in both extracts. In addition, total polyphenol, flavonoid and condensed tannin contents were: 70.427±0.113 mg GAEq/g DE and 194.986±2 mg GAEq/g DE; 19.667±1.732 mg QtEq/g DE and 23.111±0.509 mg QtEq/g DE; then 65.134±1.672 mg CEq/g DE and 203.616±4.931 mg CEq/g DE, respectively in the hydroethanolic and ethanolic extracts. The hydroethanolic extract showed a free radical scavenging activity evaluated as 13.84 ± 0.01%, whereas that of the ethanolic extract was 34.41 ± 4.70%; while measurement of antioxidant activity provided values of 24.30 ± 0.63 mg AAEq/g DE and 42.35 ± 1.20 mg AAEq /g DE, respectively. In conclusion, ethanolic extract showed better free radical scavenging and antioxidant activities, with higher contents of bioactive compounds. These results justified the common use of avocado seeds in phytotherapy in Togo for treatment of various pathologies.