COMPARATIVE EVALUATION OF ANTIOXIDANT ACTIVITY IN SEVERAL PERENNIAL ONION

Abstract

Evaluation of biochemical characteristics of 8 perennial Allium species is achieved (A. ramosum, A. caeruleum, A. erubescens, A. obliquum, A. moly, A. aflatunense, A. oreophilum and A.ursinum). High nutritional significance of separate decorative species is demonstrated. A. caeruleum is shown to be a leader in the accumulation of ascorbic acid (more than 9000 mg/100 g d.w.) and polyphenols (more than 8000 mg GAE/kg d.v.). Detected ascorbic acid concentration range for 8 studies Allium species was 568 (A. ramosum) – 9980 (A. caerulum) mg/100 g d.w.; polyphenols 1392 (A. obliquum) – 8582 (A. caerulum) mg GAE/kg d.w.; water-soluble compounds 28 (A. aflatunense, A. obliguum) – 69 (A. ramosum) mg/kg d.w.; chlorophyll 0.54 (A.oreophilum) – 1.69 (A. ursinum) mg/100 g d.w.; carotene 0.07 (A. oreophilum) – 0.25 (A.ursinum) mg/100 g d.w.; selenium 72 (A. ursinum) – 245 μg/kg d.w., (A. ramosum). Adequate consumption level of vitamin C may be provides by 6.2 g of A.caerulum leaves. Antioxidant activity of Allium species alcoholic extracts composed a range from 1.5 (A. obliquum) to 6.4 (A. ursinum) mg GAE/g d.w. A. ramosum and A. oreophilum demonstrated the highest content of total soluble solids. The highest content of photosynthetic pigments happened to be typical for A. ursinum. The ratio between antioxidant activity of alcoholic and water extracts of Allium leaves was in the range between 0.89 and 2.21 depending on plant species: the highest value was registered in leaves of A. ursinum, the lowest – in leaves of A. ramosum. In a whole the highest content of antioxidants was demonstrated for leaves of A. caerulum. The highest levels of photosynthetic pigments and antioxidant activity of alcoholic extracts were indicated in leaves of A. ursinum.