Co-Culture Yöntemi İle Pullulan Eldesi

Yıl 2013, Cilt: 9 Sayı: 1, 21 - 30, 01.03.2013

Dilara İtik Uğur Sıdal

Öz

Pullulan is a -glucan consisting mainly of maltotriose units interconnected via – 1,6 linkages. Pullulan is an extracellular polysaccharide produced by the polymorphic fungus Aureobasidium pullulans.It can be extruded easily as films that are biodegradable, is resistant to oils and grease, unaffected by temperature, impermeable to oxygen, nontoxic and therefore edible. Pullulan is a suitable polysaccharide due to its good-film-forming properties for production of edible protective films. Besides its applications in the edible film industry, pullulan has numerous applications in food, cosmetics and pharmacological industries. In this study, pullulan from Aureobasidium pullulans and Kluyveromyces marxianus strains was produced and characterized. The effect of initial pH, fermentation time, incubation temparature and initial substrate concentration was investigated. The highest pullulan concentration of 17.32 g/L was obtained for afermentation of period of 72 h with the initial substrate concentration equivalent to 50 g/L and incubation temperature at 28°C, pH 7.5

Anahtar Kelimeler

Microbial polysaccharides, pullulan, Aureobasidium pullulans, Kluyveromyces marxianus, edible films

CO-CULTURE YÖNTEMİ İLE PULLULAN ELDESİ - PULLULAN PRODUCTION BY CO-CULTURE METHOD

Öz

CO-CULTURE YÖNTEMİ İLE PULLULAN ELDESİ

Pullulan, kimyasal yapı olarak başlıca α-1,6 glikozidik bağlarıyla bağlanmış maltotrioz ünitelerinden oluşan bir glukandır. Endüstriyel açıdan öneme sahip olan bu homopolisakkarit, polimorfik bir küf olan Aureobasidium pullulans tarafından hücre dışı olarak üretilmektedir. Pullulan biyopolimeri, biyolojik olarak parçalanabilen, yağa dirençli, sıcaklıktan etkilenmeyen, oksijen geçirmeyen, toksik olmayan yapı özellikleri göstermektedir ve suda çözünebilmektedir. Pullulan, bu özelliklerinin sonucunda yenilebilen filmlerin üretiminde kullanılmak için oldukça uygun bir polisakkarittir. Pullulan yenilebilen filmlerin üretiminin yanı sıra gıda, ilaç ve kozmetik gibi birçok alanda da kullanılabilmektedir. Bu çalışmada Aureobasidium pullulans ve Kluyveromyces marxianus suşlarından pullulan üretimi ve karakterizasyonu gerçekleştirilmiştir. Bu amaçla suşların besiyerinde üremeleri ve pullulan üretme yetenekleri ve aktivite gösterdiği optimum sıcaklık, pH, inokulum zamanları saptanmıştır. Pullulan üretimi için fermentasyon şartları optimize edilmiştir. Optimum fermentasyon şartları üretim süresi 3 gün, substrat konsantrasyonu 5 %, pH 7.5 ve üretim sıcaklığı 28°C olarak saptanmştır.

PULLULAN PRODUCTION BY CO-CULTURE METHOD

Pullulan is a -glucan consisting mainly of maltotriose units interconnected via – 1,6 linkages. Pullulan is an extracellular polysaccharide produced by the polymorphic fungus Aureobasidium pullulans.It can be extruded easily as films that are biodegradable, is resistant to oils and grease, unaffected by temperature, impermeable to oxygen, nontoxic and therefore edible. Pullulan is a suitable polysaccharide due to its good-film-forming properties for production of edible protective films. Besides its applications in the edible film industry, pullulan has numerous applications in food, cosmetics and pharmacological industries. In this study, pullulan from Aureobasidium pullulans and Kluyveromyces marxianus strains was produced and characterized. The effect of initial pH, fermentation time, incubation temparature and initial substrate concentration was investigated. The highest pullulan concentration of 17.32 g/L was obtained for afermentation of period of 72 h with the initial substrate concentration equivalent to 50 g/L and incubation temperature at 28°C, pH 7.5

Anahtar Kelimeler

Mikrobiyal polisakkarit, pullulan, Aureobasidium pullulans, Kluyveromyces marxianus, yenilebilir film

Kaynakça

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