Xylanolytic enzymes production by Aspergillus niger GS1 from solid-state fermentation on corn stover and their effect on ruminal digestibility
Electron. j. biotechnol
; 14(2): 9-9, Mar. 2011. ilus, tab
Article
em En
| LILACS
| ID: lil-591939
Biblioteca responsável:
CL1.1
ABSTRACT
Hemicellulosic agricultural by-products such as corn stover (CS) are highly available materials which represent an opportunity to develop value added products. Native Aspergillus niger GS1 was used for solid-state fermentation (SSF) on alkali pre-treated CS (ACS) aimed to optimize xylanolytic enzymes production, and their effect on in vitro ruminal and true digestibility of ACS. Enzyme production was empirically modelled using a fractional factorial design 2(9-5), and the resulting significant factors were glucose, yeast extract and two mineral salts, which were arranged in a Draper-Lin optimization design at two levels. Predicted optimum xylanolytic activity of 33.6 U (mg protein)-1 was achieved at 48 hrs of SSF, and was validated by confirmatory experiments. ACS was incubated with a semipurified enzymatic extract (EE) showing a xylanolytic activity of 1600 U kg-1 dry ACS for 12 hrs before exposure to cow's ruminal liquid for 72 hrs, which led to 5 percent and 10 percent increase of in vitro ruminal and true digestibility, respectively. CS is a readily available by-product in different regions which after alkaline treatment and partial hydrolysis with the EE, may be advantageously used as supplement for ruminant feed.
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Texto completo:
1
Índice:
LILACS
Assunto principal:
Aspergillus niger
/
Zea mays
/
Ração Animal
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Electron. j. biotechnol
Assunto da revista:
BIOTECNOLOGIA
Ano de publicação:
2011
Tipo de documento:
Article