Sharif Digital Repository

In this research, the optimization of culture medium and process conditions for the production of alkaline protease enzyme from Bacillus subtilis ATCC6633 strain for use in the detergent industry has been discussed. Among all the conditions affecting the growth and production of enzymes, the stirrer cycle in the fermenter, which causes different shear rates and is one of the most important factors in the amount of mixing and aeration, was chosen for further study. At first, the results obtained from the incubator shaker were carefully examined, and then different checks were made to adjust the fermenter stirrer speed through diagrams in three flow states: 1-laminar, 2-transitional, and... 

Optimization and control of complex bioprocesses require accurate modeling. The application of flux balance analysis has gained considerable attention. In this approach, structured modeling is constructed based on metabolic genome networks. Although flux balance analysis provides an accurate model, applying it in optimization and control schemes especially model predictive control strategies often lead to bilevel optimization problems with significant computational cost. Therefore, we require a faster approach. The aim of this work is to use hybrid neural networks as a substitute for the optimization problem embedded in the dynamic model of a fermenter. In this work by proposing a hybrid... 

Dynamic modeling and control of bioprocesses, especially bioreactor and fermenter equipment, has always faced many challenges due to their complexity and high uncertainty. One scientific approach to modelling of such complex systems is the use of neural networks. Recently, an approach called hybrid networks has become popular, whose structure incorporates some of the basic rules, such as the mass balance of reactive species. Practically, it can also be used as a ‘software sensor’ or non-measurable state estimator. In this project, a bread yeast production bioreactor is used as a reference process and a hybrid neural network is used to estimate unknown parameters of biochemical reactions. In... 

Alpha amylase enzyme is one of the most important enzymes used in a wide range of industries. The enzyme is used in industries such as detergents, food, pharmaceuticals, paper making and textile. Various national and international articles have been published on this enzyme that focused on specific targets. Despite the extensive studies carried out in this area inside the country, there is still no industrial production of alpha amylase and other enzymes in our country. In the view of the fundamental problem of the lack of industrialization of these studies, in addition to the lack of a riskier investor, it seems that there is a lack of industrial vision in these studies.In this study, the... 

Dynamic modeling and process control, especially the equipment of bioreactors and fermenters, have always faced many challenges due to the complexity and high uncertainty of the kinetics of environmental reactions. Among these, semi-continuous fermentation for bioethanol production is one of the important technologies in biochemical industries. The problem of modeling as well as controlling the use of the main discontinuous and semi-continuous methods of ethanol production is the lack of uniform state conditions and the possibility of aerobic and non-aerobic multiplication conditions in two ways. The main goal of this research is to obtain a new method in modeling bioethanol fermentation and...