Simulation Investigations Towards the Development of a Bacterial Biopesticide Fed-Batch Reactor

Abstract

In this work, the growth of Bacillus thuringiensis var. israelensis, a bioinsecticide producer, is investigated. Experiments were carried out in batch mode in order to obtain kinetic model parameters that were further applied to simulate fed-batch processes. The fed-batch mode allows more flexibility in the control of the substrate concentration in the culture medium. Different techniques, such as constant feeding, "bang-bang" control and model based control (exponential feeding and singular control), were compared. For the techniques based on a model, combinations of models with and without a substrate inhibition parameter were used to represent the simulated process and the internal model of the feeding controller. Singular control based on the model with an inhibition parameter proved to be the most robust controller

Production of Bacillus thuringiensis‐based biopesticides in batch and fed batch cultures using wastewater sludge as a raw material

“…It was assumed here that a large number of cells produced a correspondingly large number of spores, and consequently a large amount of insecticidal crystal proteins or high Tx value. This also corroborated with the results of other workers 32, 33. These workers found that δ‐endotoxin production was related to spore formation in the fed batch process.…”

Modeling of growth and sporulation of Bacillus thuringiensis in an intermittent fed batch culture with total cell retention

“…The relationship between vegetative cell growth and limiting substrate concentration is described using Monod equation [1]. This kinetic model is used due to its simplicity, efficiency and following a parsimonious increasing of model complexity [15].…”

“…Bacterial entomopathogens have been extensively studied. Among them, B. thuringiensis is one of the microorganisms most frequently studied as a toxin producer [1]. Previous work developed in our laboratory showed that it is possible to increase biomass of B. thuringiensis subsp.…”

Impacts of process parameters optimization on the performance of the annular single chamber microbial fuel cell in wastewater treatment

“…As the literatures illustrate, more flexibility in the control of the substrate concentration was allowed via fed‐batch mode in the culture medium . The reactor was inoculated with 3 mL of mixed culture, which was adopted with a mixture (1:1) of wastewater and growth media solution in the fed‐batch mode once each 2 days for over 2 months.…”