title: Bioethanol production by recycled Scheffersomyces stipitis in sequential batch fermentations with high cell density using xylose and glucose mixture.
abstract: Here, it is shown three-step investigative procedures aiming to improve pentose-rich fermentations performance, involving a simple system for elevated mass production by Scheffersomyces stipitis (I), cellular recycle batch fermentations (CRBFs) at high cell density using two temperature strategies (fixed at 30°C; decreasing from 30 to 26°C) (II), and a short-term adaptation action seeking to acclimatize the microorganism in xylose rich-media (III). Cellular propagation provided 0.52gdrycellweightgRS(-1), resulting in an expressive value of 45.9gdrycellweightL(-1). The yeast robustness in CRBF was proven by effective ethanol production, reaching high xylose consumption (81%) and EtOH productivity (1.53gL(-1)h(-1)). Regarding the short-term adaptation, S. stipitis strengthened its robustness, as shown by a 6-fold increase in xylose reductase (XR) activity. The short fermentation time (20h for each batch) and the fermentation kinetics for ethanol production from xylose are quite promising.
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil; School of Chemical Engineering, State University of Campinas - UNICAMP, 500 Albert Einstein Av, Zip Code 13083-852 Campinas, SP, Brazil. Electronic address: samantha@sc.usp.br.
authors: Samantha Christine
authors: SC
authors: Santos
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil; Institute of Biology, State University of Campinas - UNICAMP, 500 Albert Einstein Av, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Amanda Silva
authors: AS
authors: de Sousa
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Suzane Rodrigues
authors: SR
authors: Dionísio
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil; Institute of Biology, State University of Campinas - UNICAMP, 500 Albert Einstein Av, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Robson
authors: R
authors: Tramontina
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Roberto
authors: R
authors: Ruller
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Fabio Márcio
authors: FM
authors: Squina
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Carlos Eduardo
authors: CE
authors: Vaz Rossell
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil; School of Chemical Engineering, State University of Campinas - UNICAMP, 500 Albert Einstein Av, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Aline Carvalho
authors: AC
authors: da Costa
authors: Brazilian Bioethanol Science and Technology Laboratory - CTBE/CNPEM, 10000 Giuseppe Maximo Scolfaro St, Zip Code 13083-852 Campinas, SP, Brazil.
authors: Jaciane Lutz
authors: JL
authors: Ienczak
mesh_terms: D061249:Batch Cell Culture Techniques / Q000379:methods*; D056804:Biofuels; D001709:Biotechnology / Q000379:methods; D002452:Cell Count; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation / Q000502:physiology*; D005947:Glucose / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism*
chemical_list: D056804:Biofuels; D000431:Ethanol; D014994:Xylose; D005947:Glucose
keywords: Acid treatment; Flocculation; Gradual temperature decrease; Propagation yeast biosystem; Short-term adaptive action