Elegant and Efficient Biotransformation for Dual Production of d-Tagatose and Bioethanol from Cheese Whey Powder.
J Agric Food Chem
; 67(3): 829-835, 2019 Jan 23.
Article
em En
| MEDLINE
| ID: mdl-30638366
ABSTRACT
In this study, the dual production of valuable d-tagatose and bioethanol from lactose and cheese whey powder is presented. First, a one-pot biosynthesis involving lactose hydrolysis and d-galactose isomerization for d-tagatose production was established using crude enzymes of recombinant Escherichia coli with l-arabinose isomerase (L-AI) at 50 °C. Compared to the current enzymatic system, only L-AI was overexpressed, because of the unexpectedly thermotolerant ß-galactosidase in E. coli BL21(DE3). Moreover, this high temperature rendered the d-glucose catabolism of E. coli inactive, while retaining all fermentable sugars for bioethanol fermentation. Thereafter, the mixed sugar syrup was fermented by Saccharomyces cerevisiae NL22. A total of 23.5 g/L d-tagatose and 26.9 g/L bioethanol was achieved from cheese whey powder containing 100 g/L lactose. This bioprocess not only provides an efficient method for the functionalization of byproduct whey, but also offsets the high production cost of d-tagatose and bioethanol.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Queijo
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Etanol
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Escherichia coli
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Proteínas do Soro do Leite
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Soro do Leite
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Hexoses
Idioma:
En
Revista:
J Agric Food Chem
Ano de publicação:
2019
Tipo de documento:
Article