Carbon-limited continuous culture was used to study the relationship between the growth of Aspergillus niger and the production of glucoamylase. The result showed that when the specific growth rate was lower than 0.068 h(-1), the production of glucoamylase was growth-associated, when the specific growth rate was higher than 0.068 h(-1), the production of glucoamylase was not growth-associated. Based on the result of continuous culture, the Monod dynamics model of glucose consumption of A. niger was constructed, Combining Herbert-Pirt equation of glucose and oxygen consumption with Luedeking-Piret equation of enzyme production, the black-box model of Aspergillus niger for enzyme production was established. The exponential fed-batch culture was designed to control the specific growth rate at 0.05 h(-1) by using this model and the highest yield for glucoamylase production by A. niger reached 0.127 g glucoamylase/g glucose. The black-box model constructed in this study successfully described the glucoamylase production by A. niger and the result of the model fitted the measured value well. The black-box model could guide the design and optimization of glucoamylase production by A. niger.
Aspergillus niger ; metabolism ; Batch Cell Culture Techniques ; Carbon ; Culture Media ; Glucan 1,4-alpha-Glucosidase ; biosynthesis ; Glucose ; Industrial Microbiology ; methods ; Oxygen

The contradiction between the increasing population and the decrease of tillable land areas is becoming more and more serious in our country. Food security is an important guarantee for sustainable development of our national economy. Photosynthesis is the basis for crop yield. Improving crop photosynthetic efficiency is one of the important approaches to increase crop yield. In this review, we summarized the recent advances in engineering photosynthetic performance by synthetic biology from three key aspects including absorption, transduction and conversion of light energy, light utilization efficiency and carbon assimilation. We also addressed the prospects of its application in increasing photosynthetic efficiency through synthetic biology principles, which may provide important theoretical support and key biotechnology to increase grain production.