The present study was performed to screen for psychrophilic yeasts that are able to secrete cold active enzymes. Yeast isolates were obtained from environmental samples from northern Turkey and examined for enzyme production at low temperatures. The isolates which were capable of cold active enzyme production on plates were identified by molecular identification techniques. It has been found that the isolates belonged to three genera of yeasts, i.e., Rhodosporidiobolus, Cystofilobasidium and Yamadazyma. The isolates were then fermented in different media at 15 °C and the pectinase, amylase and protease activities were determined in the range of 0.76-1.73, 0.5-1.57 and 2.11-10.53 U/mL, respectively. Maximum enzyme activities were found in Yamadazyma isolates for all three enzymes. To the best of our knowledge, cold active pectinase, amylase and protease production by Yamadazyma spp. were investigated for the first time in the present study. Besides, this is the first report which indicates cold active amylase production by Cystofilobasidium capitatum and pectinase production by Rhodosporidiobolus colostri. Yeast isolates obtained in this study may have potential for industrial cold active enzyme production.
Keywords: Amylase; Cold active enzymes; Pectinase; Protease; Psychrophilic–psychrotolerant yeasts; Yamadazyma spp..