Klinoptilolit ve tween-20' nin etanol üretimi üzerine etkisinin biyokütle gelişimi ve metal iyonu değişimiyle incelenmesi

Saccharomyces cerevisiae mayasının kullanıldığı bu çalışmada, fermentasyon ortamına değişen konsantrasyonlarda eklenen klinoptilolit (KLN) (1-10g/L) ve Tween-20’nin (0,1- 10 g/L), biyokütle gelişimi ve ortamdaki metal iyonu değişimi takip edilerek, etanol üretimi üzerindeki etkileri araştırılmıştır. Çalışmada yapay melas kullanılmıştır. Kontrol kültüre göre ortamda 5 g/L KLN olduğunda, kontrol kültürle 32 saatte ulaşılan etanol konsantrasyonuna 18 saatte ulaşılmış ve etanol üretim hızı 0,078 v/v.h değerinden 0,104 v/v.h değerine artış göstermiştir. KLN’nin ortamda bulunmasıyla, adsorpsiyon ve iyon değişim özelliği sayesinde, ortamda toksik miktarda bulunan Na+, Zn++ ve Mn++ iyonlarının miktarlarında azalma belirlenmiş ve bu durumun etanol hızını artıracak yönde etkilediği düşünülmüştür. Ortama Tween-20 eklenmesi durumunda biyokütle gelişimi ve etanol üretimi açısından olumlu yönde sonuç alınamamıştır.

Examination of the effect of klinoptilolite and tween-20 on ethanol production by the measurement of biomass and metal ion

In this research in which Saccharomyces cerevisiae was used, the effect of addition of (1-10g/L) klinoptilolite KLN and Tween-20 (0,1- 10 g/L), on ethanol production was examined by the measurement of biomass concentration and metal ion concentration variations with respect to time during fermentation. The synthetic molasses was used. As a result, in the presence of 5 g/L KLN, production rate is increased from control culture value of 0.078 v/v.h to 0.104 v/v.h. From the ion analyses, it was observed that the KLN added to the medium decreased the concentration of Na+,Zn++ and Mn++ cations which are known to have toxic effect on glycolysis and cell viability. This effect occurred by means of the ion exchange and adsorption properties of KLN. Tween-20 showed no net effect on biomass yield and ethanol production.

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