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Fermented dairy products mostly harbour some microbiota, also known as probiotics. Over the last years, there has been a significant increase in interest in probiotics. Among them, Pediococcus strains also exist in fermented dairy products, including kefir. However, the probiotic potential of Pediococcus strains has not been explored extensively. This study was performed to evaluate the probiotic potential of Pediococcus strains from traditionally produced kefir samples. To do this, a total of 32 kefir samples from Marmara and Central Anatolia regions in Turkey was collected. The samples were exposed to conventional microbiological analysis to culture lactic acid bacteria (LAB), followed by identification using VITEK^® mass spectrometer (MS), and molecular characterisation of Pediococcus strains by polymerase chain reaction (PCR). After that, the probiotic potential of each Pediococcus strain was tested for resistance to gastric acidity and bile salt and property of hydrophobicity. Overall, 22 strains (34.9%) were identified as Pediococcus spp. out of 63 LAB isolates. Among them, only one isolate, Pediococcus pentosaceus K6, was found to be resistant to gastric acidity, bile salt and to have hydrophobic properties. In conclusion, our study suggests that a limited number of strains could reveal their potential probiotic action on the host organism. Thus, Pediococcus strains of diverse natural origins can provide more insights into further probiotic supplement designs in human nutrition without genomic intervention.

Sourdough is an initial product used in cereal fermentation, usually prepared by adding lactic acid bacteria (LAB) strains to a mixture of wheat and water. Phytic acid present in wheat flours negatively affects the bioavailability of bread. LAB is found to have phytase activity. The present work thus aimed to determine the effect of starter culture combinations developed from phytic acid-degrading LAB (PAD-LAB) strains isolated from sourdough samples on bread sensory quality. De Man, Rogosa, and Sharpe (MRS) agar, MRS Broth, M17 agar, M17 broth, sodium phytate, and mass spectrometry were used to isolate and identify PAD-LAB from sourdough samples. The extracellular phytase activity of PAD-LAB strains was determined by spectrophotometry. Sourdough samples were prepared using different strains having high phytase activity, and breads produced from these samples were evaluated using sensory attributes. Extracellular phytase activities of 30 strains were determined by the spectrophotometric method, showing the highest value at 1109.7 U/mL, and lowest at 386.9 U/mL, with a mean of 685.1 U/mL. Sourdough samples were prepared using five different strains with high phytase activity as starting cultures; and of the four sourdough samples selected, the count of LAB increased (7.80 - 9.87 log CFU/g), pH decreased (3.53 - 4.57), and TTA (total titratable acidity) values increased (10.17 - 14.29 mL) during the fermentation period. In the sensory evaluation, bread produced with starter culture combination CS30 was preferred. In conclusion, it was determined that the bread produced with PAD-LAB strains has an advantage in terms of sensory quality as compared to the control samples.

Fermentation using Lactic Acid Bacteria (LAB) and LAB species can exhibit extracellular activities such as decreasing of antinutritional factors, in particular phytic acid (PA) or phytate. The objective of this study was to assess extracellular phytase activities of LAB in sourdough mix prepared from traditionally produced boza as starter culture. To do this, thirthy-five boza samples were collected from Central Anatolia, Marmara and Eastern Anatolia regions in Turkey to be used as starter culture for preparing sourdough mix. In each mixture, LAB strains and phytase (+) ones were screened by culture-based examination, characterized by VITEK® MS, and extracellular phytase activity of each LAB strain was determined by spectrophotometry. Overall, 29 presumptive strains of LAB were isolated. Of them, 21 were found to be phytase (+). The average extracellular phytase activity was 656.8±188.1 U//mL, and a Pediococcus pentosaceus EK1 isolate showed the highest activity as 1285.5 U/mL. In conclusion, the traditionally produced bozas have been found as potential starter culture reservoirs for sourdough fermentation with significantly higher extracellular phytase activities, thus challenging opportunitites to lower antinutritional factors, in particular phytic acid (PA) or phytate in the foods for the consumers.