GELENEKSEL KEFİR ÖRNEKLERİNDEN İZOLE EDİLEN Saccharomyces cerevisiae SUŞLARINDA EKZOPOLİSAKARİT ÜRETİMİ, KARAKTERİZASYONU VE REOLOJİK VE ANTİOKSİDAN ÖZELLİKLERİN DEĞERLENDİRİLMESİ

Öz

Bu çalışmada, geleneksel kefir örneklerinden izole edilen Saccharomyces cerevisiae suşlarından elde edilen ekzopolisakkaritlerin (EPS), karakterizasyonu ve teknofonksiyonel özellikleri araştırılmıştır. Çalışmada KY4, KY9 ve KY17 olarak adlandırılan üç farklı S. cerevisiae suşu kullanılmıştır. Sonuçlar, en yüksek EPS üretiminin 65.41±4.18 mg/L ile KY4 suşunda gözlemlendiğini göstermiştir. HPLC analizi, EPS’lerin başlıca mannozdan oluşan heteropolisakkaritler olduğu ortaya çıkarmıştır. FT-IR analizi, O-H bağlarının varlığı aracılığıyla polisakkarit yapısını doğrulamıştır. EPS'ler, yaklaşık %103'lük su tutma kapasitesi (WHC) değerleri ve %82.30 ile %90.61 arasında değişen su çözünürlük indeksi (WSI) değerleri sergilemiştir (P>0.05). Reolojik analiz, tüm EPS örneklerinin kayma incelmesi davranışı gösterdiğini göstermiştir. Ayrıca, EPS'ler güçlü antioksidan aktivite göstermiştir. Bu bulgular, kefir kaynaklı S. cerevisiae suşları tarafından üretilen EPS'lerin teknofonksiyonel ve biyoaktif özellikleri nedeniyle gıda endüstrisinde kullanılabileceğini göstermektedir.

Anahtar Kelimeler

• Kefir mayası
• S. cerevisiae
• ekzopolisakkarit
• HPLC
• reoloji
• antioksidan aktivite

EXOPOLYSACCHARIDE PRODUCTION, CHARACTERIZATION, and ASSESSMENT of RHEOLOGICAL and ANTIOXIDANT PROPERTIES in Saccharomyces cerevisiae STRAINS ISOLATED from TRADITIONAL KEFIR SAMPLES

Öz

This study aimed to investigate the production, characterization, and technofunctional properties of exopolysaccharides (EPS) produced by Saccharomyces cerevisiae strains isolated from traditional kefir samples. Three different S. cerevisiae strains, designated KY4, KY9, and KY17, were used in the study. The results showed that the highest EPS production, 65.41±4.18 mg/L, was observed in the KY4 strain. HPLC analyses revealed that the EPSs have been defined as heteropolysaccharides composed mainly of mannose. FT-IR analysis confirmed the polysaccharide structure through the presence of O-H bonds. EPSs exhibited water-holding capacity (WHC) values of approximately 103% and water solubility index (WSI) values ranging from 82.30% to 90.61%, which were not statistically significant (P>0.05). Rheological analysis demonstrated that all EPS samples displayed shear-thinning behavior. Moreover, the EPSs showed strong antioxidant activity (P≤0.05). These findings indicate that EPSs produced by kefir-derived S. cerevisiae strains can be utilized in the food industry due to their technofunctional and bioactive properties.

Anahtar Kelimeler

• Kefir yeast
• S. cerevisiae
• exopolysaccharide
• HPLC
• rheology
• antioxidant activity

Kaynakça

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