摘要：The impact of soil macronutrients on the anti-oxidant activity of the Haloxylon Salicornicum plant collected from Al-Muzahmiyah, Al-Quwaiyiyaih, Ath Thumamah and Huraymilah in the Riyadh region was investigated. Liquid chro-matography and the antioxidant activity profiling including the 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power,Folin-Ciocalteu total phenolic content, and aluminum chloride total fla-vonoid content assays were studied. Chromato-graphic analysis showed a descending order in the total phenolic content from Al-Quwaiyiyaih, Al-Muzahmiyah, Huraymilah and Ath Thumamah sites. The 2,2-diphenyl-1-picrylhydrazyl activity ranged from 67.5 to 79.0%. The corresponding 50% activity at extract concentration is 0.18-0.25 mg mL- dry extract. The ferric reducing power ranged from 30.2 to 45.4%and the 50% activity extract concentration was from 0.14 to 0.20 mg mL 1. The total phenolic content was 15.5 to 24.7 mg gallic acid equivalent g' dry weight and total fla-vonoid content was 4.2 to 6.7 mg quercetin equiva-lent g!. The correlation matrix is significant and highly positive for nitrogen and potassium with the measured antioxidant activity properties(Pearson correlation=0.952-0.993,at p<0.05).Cluster analy-sis showed a grouping of the sample sites Ath Thumamah and Al-Muzahmiyah. The principal component analysis showed the strong and essential correlation between all studied factors,except for phosphorus, on the antioxidant activity.
