Antioxidant and Antimicrobial Activity of Fruit Skin Extract From Arachis hypogaea

L. REÑONES; M. DATTILO; M. ZAMPATTI; V. ZANNONI; M. MURANO; P. SAMTER; A. STORINO; E. PLANES; R. DOMÁNICO

Sao Pedro, Sao Paulo

Congreso; 2nd Brazilian Conference on Natural Products (2nd BCNP) and XXVIII Annual Meeting on Micromolecular Evolution, Systematics and Ecology (XXVIII RESEM); 2009

Sociedade Brasileira de Química

Arachis hypogaea, which belongs to the leguminosae family, occurs in several parts of the World. In Argentina, It can be found in the central region of the country. Its edible fruit is commonly known as ?Peanut?.The Peanut skin is a by-product of blanching. This product has not economic value in Argentina despite its high content of antioxidants. The accumulation of this by-product represents an environmental problem.In this work, an alcoholic extract of the peanut skin has been obtained to evaluate its antioxidant activity to compare it with standard antioxidants like Resveratrol and Trolox, and also the antimicrobial activity has been evaluated.The antioxidant activity has been measured for the methanolic extract of defatted peanut skin (MEPS) by DPPH (2,2-diphenyl-1-picryl-hydrazyl) free-radical method. Besides, total phenols were checked with the Folin-Ciocalteu method using Gallic acid as reference standard. The antibacterial activity of this extract was tested with Escherichia coli(ATCC 25922) and Staphylococcus aureus (ATCC 29737) and antifungal activity was determinated with Curvularia sp. and Phoma epicoccina, isolated from spoiled paints.The result of antioxidant activity by DPPH method, expressed as 1/EC50, was for MEPS 8,3 mg DPPH / mg MEPS.On the other hand, standard antioxidants such as Resveratrol and Trolox showed a result of 2,1 mg DPPH / mg Resveratrol and 6,4 mg DPPH / mg Trolox. The value of 1/EC50 is directly proportional to antioxidant activity. MEPS exhibited 70,6 % of total phenols. The antibacterial and the antifungal tests showed that MEPS inhibited growth of all microorganisms tested. These studies revealed that MEPS in the conditions tested is four times more antioxidant than Resveratrol and 30% more than Trolox. The microbiological results showed that MEPS has potential as germicide. For these reasons, this extract (MEPS) could be used in food industry and chemical industries.