The suitable properties of potential probiotic lactic acid bacteria (LAB) strains (preselected among 153 strains on the basis of their potential technological properties) isolated from traditional Çubuk pickles were examined in vitro. For this purpose, these strains (21 Lactobacillus plantarum, 11 Pediococcus ethanolidurans, and 7 Lactobacillus brevis) were tested for the ability to survive at pH 2.5, resistance to bile salts, viability in the presence of pepsin-pancreatin, ability to deconjugate bile salts, cholesterol assimilation, and surface hydrophobicity properties. Most of the properties tested could be assumed to be strain-dependent. However, L. plantarum and L. brevis species were found to possess desirable probiotic properties to a greater extent compared to P. ethanolidurans. In contrast to P. ethanolidurans strains, the tested L. plantarum and L. brevis strains exhibited bile salt tolerance, albeit to different extent. All tested strains showed less resistance to intestinal conditions than gastric juice environment. Based on the survival under gastrointestinal conditions, 22 of the 39 strains were selected for further characterization. The eight strains having the highest cholesterol assimilation and surface hydrophobicity ratios could be taken as promising probiotic candidates for further in vivo studies, because of the strongest variations found among the tested strains with regard to these properties.

Bu çalışmada, turşu üretiminde kullanılabilecek starter kültürler geliştirmek amacı ile, seçilmiş endojen (yerel) Lactobacillus plantarum (MF513, MF377, MF213) ve L. plantarum MF513-Pediococcus ethanolidurans MF179 karışım suşları starter kültür olarak kullanılmış; fermantasyon süresince ve 6 aylık depolama aşamasında turşuların kimyasal, mikrobiyolojik, duyusal özellikleri değerlendirilmiştir. Starter kültürlerin fermantasyon sonuna kadar stabilitelerini koruyup koruyamadıkları, saf kültürlerin fermantasyonun başlangıcı ve bitimindeki hücre protein profilleri (SDS-PAGE) karşılaştırılarak belirlenmiştir. Karışık kültür kullanılarak üretilen turşularda en yüksek asitlik değerine (% 0.87) fermantasyonun 20. gününde ulaşıldığı belirlenmiş ve pH değeri 3.26 olarak ölçülmüştür. Kontrol örneğinde asitlik artışı starter kullanılan turşu örneklerine kıyasla daha yavaş gerçekleşmiştir. L. plantarum suşlarının fermantasyon sonuna kadar stabilitelerini korudukları ve ortamdaki baskın mikroorganizmalar oldukları belirlenmiştir. Depolama sonrası en yüksek laktik asit (1.62 g/100 mL) ve en düşük etil alkol (0.26 g/100 mL) miktarı MF513-MF179 suşlarının kullanıldığı turşu örneğinde ölçülmüştür.

In order to select eligible strains as starter cultures for the production of pickles and other fermented vegetable products, the technological characterization of the 75 lactic acid bacteria (LAB) strains was performed on the basis of salt tolerance, growth at different pH values, acid production ability, enzymatic profile and biogenic amine production. The technological characterization revealed that, among the tested LAB species (Lactobacillus plantarum, L. brevis, L. buchneri, L. namurensis, L. parabrevis, Pediococcus ethanolidurans, P. parvulus and Enterococcus casseliflavus), L. plantarum species showed the most suitable characteristics. The investigated L. plantarum strains, except for one strain (MF219), could be considered as potential starter cultures because of their desirable properties of having high rate and extent of acidification, high tolerance to pH 4.0 and 10% NaCl, and non-production of biogenic amines. It was also important to note that the tested P. ethanolidurans strains showed high salt tolerance and acid production. Most of the tested strains shared similar enzymatic characteristics including absence of proteolytic and lypolitic activities, and presence of peptidase, glucosidase and galactosidase activities. Keywords: Lactic acid bacteria, autochthonous, pickle, starter culture, technological property, enzymatic profile GELENEKSEL TURŞULARDAN İZOLE EDİLEN LAKTİK ASİT BAKTERİLERİNİN TEKNOLOJİK ÖZELLİKLERİ ÖZ