Bioconversion of starch into ethanol by a recombinant Saccharomyces cerevisiae strain YPG-AB
Process Biochemistry, cilt.37, sa.10, ss.1157-1168, 2002 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 37 Sayı: 10
- Basım Tarihi: 2002
- Doi Numarası: 10.1016/s0032-9592(01)00333-8
- Dergi Adı: Process Biochemistry
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.1157-1168
- Anahtar Kelimeler: Amylolytic enzymes, Ethanol, Fed-batch, Fermentation, Recombinant yeast, Starch bioconversion
- Boğaziçi Üniversitesi Adresli: Evet
Özet
The direct fermentation of starch into ethanol by a recombinant Saccharomyces cerevisiae strain YPG/AB, which expresses Bacillus subtilis α-amylase and Aspergillus awamori glucoamylase as separately secreted polypeptides, was investigated in both batch and fed-batch fermenter systems under controlled conditions. A 34% increase was observed in ethanol production by YPG/AB in a 40 gl-1 initial starch containing medium supplemented with 4 gl-1 glucose. Ethanol productivities were calculated as 0.35, 0.33 and 0.27 gl-1h-1 for media with pH 4.5, 5.6 and 6.5, respectively. Substrate controlled fed-batch cultures were used to increase the ethanol production rate. The amount of ethanol produced in fed-batch culture (47.5 gl-1) increased by 200% compared to batch culture (15.6 gl-1). Starch fermentation by S. cerevisiae YPG-AB strain was characterized by ethanol yields/productivities higher than those obtained in comparable fermentations on starch reported in literature. © 2002 Elsevier Science Ltd. All rights reserved.