A Mechanistic Model of Mass Transfer in the Extraction of Bioactive Compounds from Intact Sorghum Pericarp

Abstract

The extraction of phytochemical compounds from intact red sorghum grains was developed as an alternative process for producing bioactive material in the pharmaceutical industry. A mechanistic model is needed to better understand the process and enable predictive simulations for designing commercial-scale extraction systems. This paper presents a mathematical model for predicting phytochemical concentrations in the solvent and inside the pericarp of the grain at different positions during the extraction. The model is based on the mass transfer mechanism from inside the pericarp to its solid surface by diffusion, and then from the surface to a solvent during the extraction of bioactive compounds. It was numerically solved while using finite-difference approximation. The parameters considered were effective diffusivity inside the pericarp (Dep), mass transfer coefficient from the pericarp surface to the solvent (kc), and distribution coefficient (H). The model simulates the extraction performance, including the yield and bioactive compounds’ concentrations in the extract and inside the pericarp at various positions and times. A sensitivity analysis of the changes in each involved parameter provided sufficient information for increasing the performance of the model. A validation test that compared the results of the simulation with those of established analytical solutions showed that the model has high accuracy. Hence, the model can be applied in quantitative evaluations to improve productivity in the pharmaceutical industry.

Optimization of Vacuum-Microwave-Assisted Extraction of Natural Polyphenols and Flavonoids from Raw Solid Waste of the Orange Juice Producing Industry at Industrial Scale

“…In the literature, there are two types of mathematical models dedicated to microwave extraction: theoretical models based on chemical engineering principles about solid–liquid diffusion [ 39 , 40 , 41 , 42 ] and empirical statistical models based mostly on Response Surface Methodology (RSM) [ 17 , 31 , 43 , 44 , 45 ] but also on Adaptive Neuro-Fuzzy Inference System (ANFIS) statistical methodology [ 46 , 47 ].…”

Optimization of the Vacuum Microwave Assisted Extraction of the Natural Polyphenols and Flavonoids from the Raw Solid Waste of the Pomegranate Juice Producing Industry at Industrial Scale

“…Vacuum-microwave-assisted extraction is a typical paradigm of a solid–liquid extraction and many researchers have developed models for the prediction of the concentration or alternatively of the amount of the extracted bioactive compounds. In general, there are two types of mathematical models dedicated to microwave extraction: theoretical models based on chemical engineering principles of solid–liquid diffusion [ 52 , 53 , 54 , 55 ] and empirical statistical models based mostly on response surface methodology (RSM) [ 56 , 57 , 58 , 59 , 60 ] but also on adaptive neuro-fuzzy inference system (ANFIS) statistical methodology [ 61 , 62 ]. From the abovementioned models, the theoretical ones are not very useful in the case we need to obtain the optimum conditions for industrial-scale optimization of the VMAE extraction of bioactive phytochemicals.…”

Separation of proanthocyanidin from red sorghum seed extract using macroporous resin

“…The extraction process of proanthocyanidin compounds from sorghum grains has been maximized by various methods, including conventional extraction methods [5] and Ultrasound-Assisted Extraction (UAE) [6]. Quantitative evaluation of the process has been carried out with both empirical and mechanistic approaches.…”