بررسي تاثير عصاره آبي و روغن پياز (آليوم سپا) بر رشد و فعاليت آنزيم ليپاز در مالاسزيا فورفور

Effects of Aqueous and Essential Oils of Onion (Alliums cepa) on Growth and Lipase Activity in Malassezia fur fur

The effects of aqueous and essential oils of onion on growth and lipase activity by Malassezia fur fur were investigated. The best lipase producer was selected based on screening of 10 Malassezia fur fur isolates obtained from pityriasis versicolor cases on specific solid medium. Then, optimal conditions for lipase production by this isolate were determined regarding to temperature, aeration and incubation time on modified Czapeks broth. All of the isolates produced lipase on both solid and liquid culture media. The maximum lipase activity was detected for 4th days submerged cultures of M. furfur isolate 132 at 28 C. lntra - and extra cellular lipase activities at predetermined optimal conditions were determined as 0.98 - 6.16 and 12.81 - 99.87 mU/mg protein for different isolates, respectively. In contrast to onion oils, the growth of M. furfur isolate 132 was inhibited by aqueous extract as a dose - dependent manner. The minimum and maximum growth inhibition were recorded as 2.64 % and 100% for total amounts of extract equal to 0.62 and 40 milliliter, accordingly. Interestingly, lipase synthesis was inhibited by both aqueous and oil extracts as a dose - dependent manner. This inhibition reached to maximums about 66.94% and 40.72%, respectively. This is the first report on inhibition of M. fur fur lipase by aqueous and oil extracts of onion. Since fungal growth and lipase activity are considered as two important factors in pathogenesis of M. fur fur infections, substitution of currently used highly toxic antifungal drugs by natural compounds such as onion is recommended.