Release kinetics of fungicidal antimicrobials into packaged foods

Abstract

This article presents the release kinetics (RK) of a fungicidal antimicrobial agent (AMA), potassium sorbate (PS), that prolongs the shelf life of packaged food. The effects of PS release are explored on peanut and fresh bread to determine the effects of PS on Aspergillus niger (AN) microbe growth. The AN was cultured in a potato dextrose agar (PDA) medium to obtain AMA activity on the film. AMA activity of PS incorporated into cellulose acetate (CA) based film was tested on peanuts and fresh bread for an extended period of time. The RK of PS from the films was obtained by studying the de‐swelling properties of PS loaded film at room temperature (24°C) and at elevated temperature (37°C). The diffusion coefficients of PS released through the film network were obtained to be between 8.32 × 10−10 to 7.3 × 10−7 m2/s. The release exponents (n) of PS from the film occurred by anomalous transport with n‐values ranging from 0.13 to 0.16 at 24°C and 0.5 to 0.89 at 37°C. The average flux released from the CA film was consistent with the percentage PS release from the CA film showing that modeling the effective diffusion of PS from a porous media is feasible. The released PS was potent enough to inhibit the growth of AN for a week then over a period of 2 years. Thereafter, the implications of the results in designing smart food packaging for enhanced food preservation were discussed.

Sustained release of alpha‐methylacyl‐CoA racemase (AMACR) antibody‐conjugated and free doxorubicin from silica nanoparticles for prostate cancer cell growth inhibition

“…The flux of drugs from the porous nanoparticle structures was modeled using the COMSOL 5.5 Multiphysics software package. Porous structures with different pore orientations were considered in the models in which simplified homogeneity was assumed with appropriate transport across the porous surfaces 31 …”

“…The use of the correct initial and boundary conditions is critical in fluid exchange and diffusion studies 47 . Three boundary conditions were chosen based on the initial entry point of the fluid into the nanoparticle either from the left, right, upper part or the lower part of the geometry, with the flux exit point being the point directly opposite the entry point in a 2D geometry and the insulating boundary, while the diffusion process is ongoing 31 . In the first phase of this simulation, the boundary conditions would be set based on some defining equations.…”

“…The first boundary condition corresponds to the fluid entry boundary, and it is set as the concentration boundary. This was expressed as 31,48 : where is the initial concentration of the drug.…”

“…The second boundary condition represents the flux exit boundary 31,48 . This was represented as: …”

“…To understand the drug release kinetics, various mathematical models were used to fit the in vitro drug release data. These included: the zeroth order, first order, second order, Higuchi, and Korsmeyer-Peppas models 31,32 that are described briefly in this section.…”