Phytase activity screening
The initial screening for phytase activity revealed some differences between the strains found (Fig. 2). Three groups can be distinguished after 24 h incubation: no, moderate and extensive IP6 degradation. None of the strains identified as C. glabrata showed any phytase capacity in YPD. The same was true also for P. norvegensis, P. guilliermondii, P. burtonii and all three strains of S. cerevisiae. Strains identified as H. guilliermondii and I. orientalis showed the highest phytase activity; I. orientalis TY13 and H. guilliermondii TY14 and TY20 completely degraded all phytate. Strains of P. anomala and K. marxianus exhibited either no phytase activity (P. anomala TY07 and K. marxianus TY17) or moderate activity (P. anomala TY06 and TY16 as well as K. marxianus TY04).