Antioxidant and antimicrobial activities of solidago virgaurea extracts

Abstract

Solidago virgaurea is an herbaceous perennial plant of the family Asteraceae. It has been traditionally used to terat urinary tract, nephrolithiasis and prostate. Our objective was to determine the antioxidant activities, reducing powers, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scaenging activities and antimicrobial activities of metanol and hot water extracts of S. virgaurea from Bursa region in Turkey. The highest antioxidant activity was found in the metanol extract. The reducing power of the metanol extract was the highest, but its reducing power was markedly lower than that of ascorbic acid. The highest DPPH radical-scavenging activity was found in the metanol, with 50% DPPH radical scavenging at a concentration of 74.66 mu gml(-1) dried metanol extract, while at the same concentration of dried water extract the value was 22.16%. Metanol extract of S. virgaurea showed antimicrobial activities against Staphylococcus aureus, Enterobacter fecalis, Escherichia coli and Bacillus cereus. The MIC valaues against bacteria 50 mu gml(-1). It was found that metanol and water extracts of S. virgaurea show antioxidant activity. It has been reported that there is an inverse relationship between dietary intake of antioxidant-rich foods and the incidence of a number of human diseases, therefore these results are interesting. This plant, which may contain both polar and apolar antioxidant compounds, could be a potential source of natural antioxidants.