Isolation and identification of lactic acid bacteria with phytase activity from sourdough

Wholemeal bread is strongly recommended due to its nutritional value. However, whole‐grain foods contain a high level of phytic acid, an antinutritional factor that decreases the mineral bioavailability. The objective of this study was isolation and identification of lactic acid bacteria with phytase activity to find a suitable starter for bread‐making. Wheat–legume sourdoughs were prepared by the back‐slopping procedure. Lactic acid bacteria were isolated from the sourdough of wheat flour–mung bean, and their phytase activity was tested in the solid and liquid media. Out of the nine phytase‐active isolates in the solid medium, only three isolates produced extracellular phytase in the liquid medium with activity ranging from 16.3 to 53.2 (U/ml). These isolates belonged to species Weissella confusa mk.zh95 and Pediococcus pentosaceus. The highest phytase activity was found for Weissella confusa mk.zh95. Weissella confusa mk.zh95 is considered an interesting source of phytase during cereals and legumes fermentation which improves the bioavailability of minerals. Lactic acid bacteria (LAB) with phytase activity isolated from different sourdoughs of wheat–legume in order to find a suitable starter for bread‐making. Three strains showed extracellular phytase activity ranging between 16.3 and 53.2 U/ml. The highest phytase activity was observed in the sourdough inoculated with Weissella confusa mk.zh95. Fermentation by phytase‐positive LAB caused more acidification comparing to the control.