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

Abstract

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.

Kinetics of Phosphate Ions and Phytase Activity Production for Lactic Acid-Producing Bacteria Utilizing Milling and Whitening Stages Rice Bran as Biopolymer Substrates

“…The majority of strains showed higher extracellular activity compared to their intracellular counterparts. This is consistent with the work of Mohammadi-Kouchesfahani et al [61], who argued that LAB strains with significant extracellular PE act would be more effective as starter cultures in the bakery industry. The presence of high IP6 levels in wholemeal bread can affect mineral bioavailability for consumers, and extracellular PE during sourdough production could efficiently dissociate IP6.…”

Pediococcus pentosaceus, a future additive or probiotic candidate

“…To the best of our knowledge, phytic acid is harmful to mineral bioavailability. Moreover, sourdough-derived P. pentosaceus B3 and B11 and chicken intestine-derived P. pentosaceus CFR R38 and R35 were able to degrade phytate and promote mineral bioavailability [ 52 , 53 ]. Similarly, from among 60 strains of LAB from cereal- and pulse-based fermented mixtures, P. pentosaceus CFR R123 not only significantly improved the availability of calcium but also reduced cholesterol and β-galactosidase levels.…”

Characterization of functional effects of different LAB isolated from sourdoughs in Turkey

“…plantarum 45MK-32, which has the highest proteolytic activity in our study, was the most efficient to alter the pH of MRS medium leading to the formation of favourable conditions for proteinase activity. Whole meal bread consumption has remarkably increased since awareness of its nutritionally valuable components, such as dietary fibers, vitamins, minerals, complex carbohydrates, and proteins (Mohammadi-Kouchesfahani et al 2019). However, phytic acid, the major phosphorus form in cereal grains including wheat, impedes the absorption of Fe +2 , Zn +2 , Ca +2 , Mg +2 , Cu +2 , and Mn +2 ; thus, mineral deficiencies are promoted (Ficco et al 2009;Liu et al 2019).…”