History

Lupinus termis (lupine) is well-known plant but yet, little information about its allelopathic potential. In the present study, we evaluated the effects of different concentrations (20, 40, 60, 80 and 100 100 µgml-1) of the aqueous extract of lupine leaf extract from irradiated and non-irradiated seedling with UVC on seed germination and antioxidant system in Portulaca oleracea leaves. Treatment of Portulaca seeds with lupine leaf extracts reduced germination percentage depending on the concentration. The treatment resulted in the increase of the non- enzymatic antioxidants including total phenols, total flavonoids, vitamin E (tocopherol), vitamin c (ascorbate) and glutathione in Portulaca leaves in concentration-dependent manner. The activities of phenylalanine ammonia-lyase (PAL, EC: 4.3.1.24), cinnamate-4-hydroxylase (C4H, EC: 1.14. 13.11) and flavonoid-3-monooxygenase (F3H, EC: 1.14.14.82) were enhanced by lupine leaf extracts Activities of the antioxidant enzymes such as superoxide dismutase (SOD, EC: 1.15.1.1), ascorbate peroxidase (APX, EC: 1.11.1.11) and glutathione reductase (GR, EC: 1.8.1.7) were enhanced by the allelopathic effect of lupine leaf extracts. The estimation of antioxidant activity was conducted by the assays of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity. The antioxidant activity in Portulaca leaves increased by lupine leaf extract particularly that from irradiated lupine seedlings. The present results recommend the potential application of the aqueous extracts of irradiated lupines termis persicum to control Portulaca oleracea weed. Furthermore, P. oleracea revealed an interesting phytochemical pattern with sound antioxidant activity that assigns this with potential bioactivities.