This work aimed to develop the submerged cultivation conditions for improved exopolysaccharides (EPS) production by Armillaria luteo-virens Sacc. The effects of culture temperature, aeration rate, inoculum level, initial pH, and additives on EPS formation and mycelial growth are investigated. The aeration rate, initial pH, and inoculum level significantly affected EPS production under the submerged cultivation. The developed conditions were as follows: cultivation temperature 23 °C, initial pH 5.0, aeration rate 0.5 vvm, 0.5% Tween 80, inoculum level 5% (v/v), and shaking speed 120 r/min. Under the developed conditions, the highest EPS production was 13.01 g/L at 5 days culture time. EPS production was examined in a 5 L bioreactor, and an unstructured kinetic model for EPS formation was well developed. The verified investigations in the large-scale cultivation system showed that the developed models are able to predict the submerged cultivation process of EPS formation. Current results revealed that the submerged cultivation conditions can be utilized to control EPS production, and the unstructured models developed are suitable for explaining EPS production by A. luteo-virens Sacc QH in a large-scale cultivation bioreactor.

The agro-byproduct culture medium for α-galactosidase production by Aspergillus niger zju-Y1 was optimized with flask-SSF via response surface methodology, maximum α-galactosidase yield at the level of 230.159 U/g dry matter was achieved by using wheat bran and soybean meal as culture medium components. Furthermore, based on the flask-SSF results, the three-section-control strategy was developed for scale-up SSF, making fermentation steadily and efficiently, and the α-galactosidase activity hitting to 174.410 U/g dry matter, which is close to the result of flask-SSF. The results demonstrated that a feasible scale-up SSF mode for α-galactosidase production is successfully set up by combining the utilization of agro-byproduct culture medium and three-section-control strategy.