To optimize the fermentation conditions for Aspergillus niger strains with high-yield α-glucosidase.
Using Aspergillus niger as the fermentation strain and α-glucosidase activity as the evaluation index, single-factor optimization was employed to investigate fermentation conditions including temperature, rotation speed and inoculum size. Orthogonal experiment was applied to optimize the components of the fermentation medium.
The optimal fermentation conditions for α-glucosidase production by Aspergillus niger were as follows: Malt extract powder 4%, yeast peptone 3%, Tween X-100 0.10%, K2HPO4·3H2O 0.5%, MgSO4·7H2O 0.05%, initial fermentation pH 5.9 and inoculum size 2%. Under these conditions, the α-glucosidase activity reached 0.530 U/mL, which was 28% higher than that before optimization.
The optimized fermentation conditions and medium components for α-glucosidase production by Aspergillus niger in this study significantly enhance the α-glucosidase activity compared with the unoptimized ones(P<0.05). The optimized strategy is simple and feasible, which lays a theoretical foundation for the further industrial application and commercial development of α-glucosidase.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |