Antioxidant potential of some natural and semi-synthetic flavonoid derivatives and the extracts from Maclura pomifera (Rafin.) Schneider (osage orange) and its essential oil composition

Abstract

Objective: The antioxidant potential of various extracts were obtained from the leaf and fruit of Maclura pomifera (Rafin.) Schneider (Moraceae) along with its major isoflavonoids; osajin and pomiferin, their semi-synthetic derivatives; iso-osajin and iso-pomiferin and macluraxanthone, which were assayed. Methods: The extracts and compounds were subjected to six experimental models including 2,2'-diphenyl-1-picrylhydrazyl (DPPH), N, N-dimethyl-p-phenylendiamine (DMPD+), and nitric oxide (NO) radical scavenging activity, metal-chelating capacity, ferric-(FRAP) and phosphomolibdenum- reducing antioxidant power (PRAP) assays by using ELISA methods. Results: The fruit aqueous extract exerted higher scavenging activity against DMPD and NO radicals, while the fruit ethyl acetate extract was the most active against DPPH radical (68.61 +/- 2.53%). Among the tested compounds, the highest DPPH (91.74 +/- 0.26%) and DMPD (30.63 +/- 1.31%) radical scavenging effect was observed with macluraxanthone, while pomiferin and iso-pomiferin exhibited better activity than osajin and iso-osajin in all assays except the metal-chelation capacity assay. Phytol was the major compound in both the leaf oils, while the fruit essential oil contained beta-caryophyllene as the main component (69.3%). Discussion and Conclusion: The current study covers particularly antioxidant capacity of iso-osajin, iso-pomiferin, and macluraxanthone by the aforementioned methods and, among them; pomiferin seems to be a natural possible antioxidant agent.