Data/hora: 10/06/2024 08:02:40

Provedor de dados: | 58
País: | Brazil
Título: | Enhancing inulinase yield by irradiation mutation associated with optimization of culture conditions
Autores: | Gou,Yafeng; Li,Jianhua; Zhu,Junbao; Xu,Wanyun; Gao,Jianfeng.
Data: | 2015-09-01
Ano: | 2015
Palavras-chave: | Inulin; Ethanol fermentation; Inulinase; Central composite design; Response surface methodology.
Resumo: | A new inulinase-producing strain was isolated from rhizosphere soils of Jerusalem artichoke collected from Shihezi (Xinjiang, China) using Jerusalem artichoke power (JAP) as sole carbon source. It was identified as an Aspergillus niger strain by analysis of 16S rRNA. To improve inulinase production, this fungus was subjected to mutagenesis induced by 60Co γ-irradiation. A genetically stable mutant (designated E12) was obtained and it showed 2.7-fold higher inulinase activity (128 U/mL) than the parental strain in the supernatant of a submerged culture. Sequential methodology was used to optimize the inulinase production of stain E12. A screening trial was first performed using Plackett-Burman design and variables with statistically significant effects on inulinase bio-production were identified. These significant factors were further optimized by central composite design experiments and response surface methodology. Finally, it was found that the maximum inulinase production (185 U/mL) could be achieved under the optimized conditions namely pH 7.0, yeast extract concentration of 5.0 g/L, JAP concentration of 66.5 g/L, peptone concentration of 29.1 g/L, solution volume of 49.4 mL in 250-mL shake flasks, agitation speed of 180 rpm, and fermentation time of 60 h. The yield of inulinase under optimized culture conditions was approximately 1.4-fold of that obtained by using basal culture medium. These findings are of significance for the potential industrial application of the mutant E12.
Tipo: | Info:eu-repo/semantics/article
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822015000300911
Editor: | Sociedade Brasileira de Microbiologia
Relação: | 10.1590/S1517-838246320140918
Formato: | text/html
Fonte: | Brazilian Journal of Microbiology  v.46 n.3 2015
Fonte: | info:eu-repo/semantics/openAccess