Phytochemical, antioxidant and antimicrobial activities of flowers of phlox drummondii

ABSTRACT

The extracts and fractions of flowers of Phloxdrum mondii were evaluated for antimicrobial and antioxidant activities. Their purification resulted in the isolation of four known constituents of which uracil and 2-methyl-1,2,3,4- butantetrol have not been obtained previously from any specie of the genus Phlox, while isolation of the flavonoid glycosides [1] and [2] have been reported from the flowers of the plant. Among all the samples PhFC and its fraction PhFCM showed significant activity against both bacteria and fungi. Flavonoid glycoside O-rhamnosyl-6-C-xylosylapigenin 1 and O-rhamnosyl- 6- C-xylosylluteolin 2 demonstrated antioxidant activity which were of same magnitude [IC50 42.67 +/- 4.99 micro g/ml and 46.33 +/- 6.65 micro g/ml, respectively]. Thereby, suggesting that the presence or absence of hydroxyl group at position C-3' does not play a significant role in said activity in this case. Interestingly, the mixture of 1 and 2 apparently showed synergism as reflected by 45% improvement in antioxidant activity as compared to the individual values obtained for either 1 or 2