Identification of yeasts isolated from native Iranian sourdough using PCR technique

The sourdough is a paste that is madeupof water and flour and yeasts and lactic acid bacteria are its key microorganisms. Sourdough fermentation process is based on lactic and alcoholic fermentation that is done by lactic acid bacteria and yeasts respectively. Also these microorganisms play an important role in improving the flavor, texture and shelf life of bakery products. In this research, samples of sourdough were collected from different regions of Iran to verify the yeast flora, were studied.Toachieve this aim the yeasts isolated by the colony morphology method and then had reproduced 26S rRNA gene whit generalprimers for identification exactly. The sections that replicated sent to bioscience company UK for Sequencing.Thencompare theresultingsequence whit sequencesinthe gene bank(NCBI), the yeast species studied were identified. The resultsshowed that theyeasts isolated included Saccharomyces cerevisiae, Saccharomyces exiguous, Issatchenkiaorientalis, Torulasporafranciscae, Torulasporadelbrueckii, Pichiafermentans that dominantspecies related to Saccharomyces cerevisiae andSaccharomyces exiguous.