Aqueous ammonia soaking of switchgrass followed by simultaneous saccharification and fermentation

Isci A., Himmelsbach J. N., Pometto III A. L., Raman D. R., Anex R. P.

Applied Biochemistry and Biotechnology, cilt.144, sa.1, ss.69-77, 2008 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 144 Sayı: 1
  • Basım Tarihi: 2008
  • Doi Numarası: 10.1007/s12010-007-8008-z
  • Dergi Adı: Applied Biochemistry and Biotechnology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.69-77
  • Anahtar Kelimeler: Aqueous ammonia soaking, Ethanol production, Pretreatment, Simultaneous saccharification and fermentation (SSF), Switchgrass
  • Ankara Üniversitesi Adresli: Hayır

Özet

Simultaneous saccharification and fermentation (SSF) of switchgrass was performed following aqueous ammonia pretreatment. Switchgrass was soaked in aqueous ammonium hydroxide (30%) with different liquid-solid ratios (5 and 10 ml/g) for either 5 or 10 days. The pretreatment was carried out at atmospheric conditions without agitation. A 40-50% delignification (Klason lignin basis) was achieved, whereas cellulose content remained unchanged and hemicellulose content decreased by approximately 50%. The Sacccharomyces cerevisiae (D 5A)-mediated SSF of ammonia-treated switchgrass was investigated at two glucan loadings (3 and 6%) and three enzyme loadings (26, 38.5, and 77 FPU/g cellulose), using Spezyme CP. The percentage of maximum theoretical ethanol yield achieved was 72. Liquid-solid ratio and steeping time affected lignin removal slightly, but did not cause a significant change in overall ethanol conversion yields at sufficiently high enzyme loadings. These results suggest that ammonia steeping may be an effective method of pretreatment for lignocellulosic feedstocks. © 2007 Humana Press Inc.