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Sweet sorghum and energy cane (high fiber cane) are potential crops for conversion into fuels and chemicals due to their low agricultural input requirements, potentially high fiber content and processing similarities with established sugarcane crops. A conceptual approach to a biorefinery producing fuels and chemicals from sweet sorghum and energy cane is proposed. The front-end of the plant processes 10,000 t/d of feedstock to extract convertible sugars by milling and concentrate them into storable syrups. The latter can be processed into gasoline, jet fuel and isoprene using proprietary technologies. The fiber remaining after extraction, called bagasse, is used in the boilers of the front-end plant to provide steam and power for entire facility and to produce additional second generation sugars by pretreatment and hydrolysis in a lignocellulosic conversion plant. Material and energy balances for the front-end plant were calculated using SugarsTM software. Results show that for the selected variety of energy cane, up to 46% of bagasse is available for further lignocellulosic conversion resulting in production of additional 33.6% of sugars. In this case, however, surplus electricity production is reduced by 86%. Calculations for sweet sorghum follow the same trend. Results show that a 13% reduction in fiber content by processing sweet sorghum instead of energy cane, reduces power export by 71% and second generation sugars by 40%.

In this work, a mechanistic model for predicting the dynamic behavior of extracellular and intracellular nutrients, biomass production, and the main metabolites involved in the central carbon metabolism in plant cell cultures of Thevetia peruviana is presented. The proposed model is the first mechanistic model implemented for plant cell cultures of this species, and includes 28 metabolites, 33 metabolic reactions, and 61 parameters. Given the over-parametrization of the model, its nonlinear nature and the strong correlation among the effects of the parameters, a parameter estimation routine based on identifiability analysis was implemented. This routine reduces the parameter's search space by selecting the most sensitive and linearly independent parameters. Results have shown that only 19 parameters are identifiable. Finally, the model was used for analyzing the fluxes distribution in plant cell cultures of T. peruviana. This analysis shows high uptake of phosphates and parallel uptake of glucose and fructose. Furthermore, it has pointed out the main central carbon metabolism routes for promoting biomass production in this cell culture.

In this work, the development and application of published models for describing the behavior of plant cell cultures is reviewed. The structure of each type of model is analyzed and the new tendencies for the modeling of biotechnological processes that can be applied in plant cell cultures are presented. This review is a tool for clarifying the main features that characterize each type of model in the field of plant cell cultures and can be used as a support on the selection of the more suitable model type, taking into account the purpose of specific research.