Moroccan Journal of Chemistry, Vol 8, No 2 (2020)

Antioxidant activities, total phenol an flavonoid contents of two Teucrium polium subspecies extracts

Y. EL ATKI, I. Aouam, F. El Kamari, A. Taroq, H. Zejli, M. Taleb, B. Lyoussi, A. Abdellaoui

Abstract


The soxhlet extracts of two subspecies from Moroccan Teucrium polium were examined for their antioxidant activities, total polyphenol and total flavonoids contents.

The Antioxidant activities was evaluated in vitro spectrophotometrically using  four methods, such as ABTS+·, 1,1-diphenyl-2-picrylhydrzyl (DPPH·), ferric reducing antioxidant power and phosphomolybdenum assay. Total polyphenol and flavonoid contents  were measured using Folin-Ciocalteu test and aluminum chloride colorimetric method, respectively.

The total phenol contents, flavonoids contents and antioxidant activities of T. polium subsp. polium extracts were higher than T. polium subsp. aurum. The phenols contents ranged from 112.27 to 4.38 mg GA E/ g dry extract. The total flavonoids varied between 174.57 and 40.42 mg RE/ g dry weight. The extract showed significant scavenging activity of  ABTS+·  and  DPPH·, with IC50 values ranging from 0.38 to 5 mg/ml and from 0.23 to 4.02 mg/ml, respectively. Moreover all extracts showed a good ferric reducing antioxidant power with EC50 values varying between 0.19 and 3.94 mg/ml. The total antioxidant capacity assay revealed that the water extract of T. polium subsp. aurum had a high activity with a value of 220 mg VitCE/g dry weight. The ethyl acetate extract has a weak antioxidant activity in the four tests. These results shows that Moroccan T. polium subspecies are a rich source of phenols and natural antioxidant compounds, which can be used as a natural food preservative.