caa a22 4500 606212191 CHVBK 20210128101041.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s10295-015-1661-2 doi (NATIONALLICENCE)springer-10.1007/s10295-015-1661-2 The modeling of ethanol production by Kluyveromyces marxianus using whey as substrate in continuous A-Stat bioreactors [Elektronische Daten] [Sabrina Gabardo, Gabriela Pereira, Rosane Rech, Marco Ayub] We investigated the kinetics of whey bioconversion into ethanol by Kluyveromyces marxianus in continuous bioreactors using the "accelerostat technique” (A-stat). Cultivations using free and Ca-alginate immobilized cells were evaluated using two different acceleration rates (a). The kinetic profiles of these systems were modeled using four different unstructured models, differing in the expressions for the specific growth (μ) and substrate consumption rates (r s), taking into account substrate limitation and product inhibition. Experimental data showed that the dilution rate (D) directly affected cell physiology and metabolism. The specific growth rate followed the dilution rate (μ≈D) for the lowest acceleration rate (a=0.0015h−2), condition in which the highest ethanol yield (0.52gg−1) was obtained. The highest acceleration rate (a=0.00667h−2) led to a lower ethanol yield (0.40gg−1) in the system where free cells were used, whereas with immobilized cells ethanol yields increased by 23% (0.49gg−1). Among the evaluated models, Monod and Levenspiel combined with Ghose and Tyagi models were found to be more appropriate for describing the kinetics of whey bioconversion into ethanol. These results may be useful in scaling up the process for ethanol production from whey. Society for Industrial Microbiology and Biotechnology, 2015 Bioprocess modeling nationallicence Ethanol nationallicence Kluyveromyces marxianus nationallicence Continuous fermentation nationallicence A-stat control nationallicence Whey nationallicence Gabardo Sabrina Biotechnology and Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut Pereira Gabriela Biotechnology and Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut Rech Rosane Food Science and Technology Institute, Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut Ayub Marco Biotechnology and Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut Journal of Industrial Microbiology & Biotechnology Springer Berlin Heidelberg 42/9(2015-09-01), 1243-1253 1367-5435 42:9<1243 2015 42 10295 https://doi.org/10.1007/s10295-015-1661-2 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10295-015-1661-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gabardo Sabrina Biotechnology and Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut NATIONALLICENCE 700 1- Pereira Gabriela Biotechnology and Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut NATIONALLICENCE 700 1- Rech Rosane Food Science and Technology Institute, Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut NATIONALLICENCE 700 1- Ayub Marco Biotechnology and Biochemical Engineering Laboratory (BiotecLab), Federal University of Rio Grande do Sul, Av. Bento Gonçalves, 9500, PO Box 15090, 91501-970, Porto Alegre, RS, Brazil aut NATIONALLICENCE 773 0- Journal of Industrial Microbiology & Biotechnology Springer Berlin Heidelberg 42/9(2015-09-01), 1243-1253 1367-5435 42:9<1243 2015 42 10295