Kinetic and thermodynamic study of the photochemical degradation of patulin

Evaluation of ozonated and ultrasonically treated corn starch as an adsorbent for patulin in buffer solutions

This study evaluates the potential of ozonated corn starch (OCS) and ultrasonicated ozonated corn starch (USOCS) as adsorbents for patulin removal in buffer solutions. The results indicated that dual modification significantly altered the starch's structure, introducing functional groups such as carbonyl and carboxyl groups, and increasing its surface area. These modifications led to enhanced patulin adsorption capacity. Adsorption efficiency was tested across different adsorbent doses (150 mg, 200 mg, 250 mg) and contact times (15, 30, 45, and 60 min). The highest removal efficiency of 92.5% was recorded for the 250 mg dose at 60 min, with USOCS showing superior performance compared to native corn starch and OCS. Kinetic studies revealed that the pseudo-second-order model provided the best fit for the adsorption process, indicating chemisorption as the dominant mechanism. The Langmuir and Freundlich isotherms were used to describe the adsorption behavior, with a maximum adsorption capacity (qmax) of 15.19 µg/mg and a Langmuir constant (KL) of 54.00 L/µg for the 250 mg dose. Additionally, the modified starch demonstrated consistent adsorption performance at varying concentrations, with a favorable adsorption intensity (n > 1), supporting its potential for practical applications. These findings highlight the modified corn starch as an efficient, biodegradable, and low-cost adsorbent suitable for mitigating patulin contamination in food products, offering a sustainable alternative for improving food safety.

Identification and application of a novel patulin degrading enzyme from Cyberlindnera fabianii

Patulin (PAT) is a mycotoxin commonly found in fruits and vegetables, prompting the need for effective removal and detoxification methods, which have garnered significant research attention in recent years. Among these methods, the utilization of microbial-derived enzymes stands out due to their mild operating conditions, specificity in targeted functional groups, and the production of non-toxic by-products, making it a preferred degradation approach. In this study, a novel PAT-degrading enzyme derived from Cyberlindnera fabianii (Cyfa-SDR) was identified, demonstrating its highest catalytic activity at pH 7.0 and 80 °C against PAT. This temperature tolerance level represents the highest reported for PAT-degrading enzymes to date. The enzyme was further characterized as a short-chain dehydrogenase through analysis of its amino acid composition, conserved GXXXGXG motif, and dependency on NADPH. Moreover, the study evaluated the efficiency of PAT degradation by Cyfa-SDR at varying substrate and enzyme concentrations, surpassing the performance of other PAT-degrading enzymes, thus highlighting its substantial potential for the biological control of PAT. In conclusion, the enzymatic treatment using the PAT-degrading enzyme Cyfa-SDR presents a viable and promising solution for enhancing the quality and safety of fruit juice.

Optimization of Seleno-chitosan-phytic acid nanocomplex for efficient removal of patulin from apple juice

A novel and effective adsorbent known as Seleno-chitosan-phytic acid nanocomplex (Se-CS-PA) has been developed specifically for efficiently removing patulin (PAT) from a simulated juice solution. The synthesis of Se-CS-PA nanocomplex was confirmed through Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), and energy dispersive X-Ray (EDX) analyses. Response surface methodology (RSM) was employed using central composite design (CCD) to examine the impact of four independent variables (PA concentration, amount of nano-complex, duration of interaction between PAT and nano-complex, and initial concentration of PAT) on the removal of PAT. PA concentration of 0.1 % with 2.1 g Se-CS-PA nanocomplex according to RSM polynomial equation and apple juice with 25 μg.L-1 PAT yielded a remarkable adsorption rate of 94.23 % and 87.52 % respectively after 7 h. The process of PAT adsorption was explained using the pseudo-first-order model (R2 = 0.8858) for the kinetic model and the Freundlich isotherm (R2 = 0.9988) for the isotherm model.

Reduction the contamination of patulin during the brewing of apple cider and its characteristics

Patulin is one of the most significant food safety problems in fruit and derived products. The reduction of patulin contamination in food processing has always been the focus of research. In this study, nine yeast strains were applied for the brewing of apple cider and the fate of patulin was determined. In this process, the patulin contamination can be decreased by adsorption onto and degradation of yeast cells in the main fermentation (20.8-49.1%), as well as the adsorption removal during clarification (18.7-58%), inverted cans (21.3-31.4%) and aging (1.0-5.8%). Saccharomyces cerevisiae (1027) was selected to reveal the elimination mechanism of patulin in main fermentation. The decrease of patulin content was mainly due to degradation and the intracellular enzymes played a more important role than extracellular ones. In addition, the synthesis of enzymes was related to the induction of patulin. Furthermore, the degradation product of patulin in the main fermentation was identified as E-ascladiol, which is less toxic than patulin. Based on the representative strain of S. cerevisiae 1027, patulin contamination can be effectively eliminated during apple cider brewing. This study provides a new insight into eliminating patulin contamination in the brewing of apple cider.

Thermal Stability and Degradation Kinetics of Patulin in Highly Acidic Conditions: Impact of Cysteine

The thermal stability and degradation kinetics of patulin (PAT, 10 μmol/L) in pH 3.5 of phosphoric-citric acid buffer solutions in the absence and presence of cysteine (CYS, 30 μmol/L) were investigated at temperatures ranging from 90 to 150 °C. The zero-, first-, and second-order models and the Weibull model were used to fit the degradation process of patulin. Both the first-order kinetic model and Weibull model better described the degradation of patulin in the presence of cysteine while it was complexed to simulate them in the absence of cysteine with various models at different temperatures based on the correlation coefficients (R² > 0.90). At the same reaction time, cysteine and temperature significantly affected the degradation efficiency of patulin in highly acidic conditions (p < 0.01). The rate constants (k_T) for patulin degradation with cysteine (0.0036-0.3200 μg/L·min) were far more than those of treatments without cysteine (0.0012-0.1614 μg/L·min), and the activation energy (E_a = 43.89 kJ/mol) was far less than that of treatment without cysteine (61.74 kJ/mol). Increasing temperature could obviously improve the degradation efficiency of patulin, regardless of the presence of cysteine. Thus, both cysteine and high temperature decreased the stability of patulin in highly acidic conditions and improved its degradation efficiency, which could be applied to guide the detoxification of patulin by cysteine in the juice processing industry.

Patulin in food: A mycotoxin concern for human health and its management strategies

The mycotoxin patulin is primarily produced as a secondary metabolite by numerous fungal species and predominantly by Aspergillus, Byssochlamys, and Penicillium species. It is generally associated with fungal infected food materials. Penicillium expansum is considered the only fungal species liable for patulin contamination in pome fruits, especially in apples and apple-based products. This toxin in food poses serious health concerns and economic threat, which has aroused the need to adopt effective detection and mitigation strategies. Understanding its origin sources and biosynthetic mechanism stands essential for efficiently designing a management strategy against this fungal contamination. This review aims to present an updated outline of the sources of patulin occurrence in different foods and their biosynthetic mechanisms. It further provides information regarding the detrimental effects of patulin on human and agriculture as well as its effective detection, management, and control strategies.

Patulin, ergosterol and Howard mold count (HMC): Which one is the best quality indicator for tomatoes?

Ergosterol, an important constituent of fungal cell wall, was started to be used as a quality parameter for the tomatoes and derivatives instead of Howard mold count (HMC). In addition, patulin is another important microbiological quality indicator of molds such as Penicillium, Aspergillus, and Byssochlamys. In this study, it is aimed to identify the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which has the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. As the rotten proportion increased, HMC, ergosterol, and patulin values increased. Linear correlations (r) between HMC, ergosterol, patulin, and rotten proportion were calculated as 0.99, 0.99, and 0.98, respectively. In addition, linear correlations between HMC and ergosterol (r = 0.95), HMC and patulin (r = 0.95) and ergosterol and patulin (r = 0.98) were found. In contrast, non-linear correlation between pH, brix and titratable acidity, and the rotten proportion was determined. PRACTICAL APPLICATIONS: The manuscript has provided the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which have the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. Linear correlations between rotten proportions of tomatoes and HMC, ergosterol, patulin and between HMC and ergosterol, HMC and patulin, and ergosterol and patulin were determined in juices produced from rotten tomatoes. Patulin indicated correlation with HMC and ergosterol in juices produced from rotten tomatoes. In addition to HMC and ergosterol, patulin has great potential for the assessment of tomato products as associated with the rotten proportion.

Kinetic and thermodynamic compensation study of the hydration of faba beans (Vicia faba L.)

This work applies kinetic and thermodynamic compensation to evaluate the kinetics of hydration of faba beans. A mechanism was proposed, consisting of a zero-order adsorption step followed by a first-order desorption step, with both reactions going through a transition state with a previous equilibrium stage. The kinetic constants were obtained from a previous study for pHs 3, 6, 9 and 12 and at temperatures of 20, 35, 50 and 65 °C. From these kinetic constants, the equilibrium constants were calculated using the Eyring equation for each pH value and temperature. The kinetic constants were fitted to the Arrhenius equation and the set of pair estimates for lnk₀ and the activation energy followed the straight lines that cause the kinetic compensation, with isokinetic temperatures of -10.3 °C found for the zero-order adsorption step and 8.4 °C for the first-order desorption step. The equilibrium constants were fitted to the Van't Hoff equation and the set of pair estimates for the activation enthalpy and the activation entropy followed the straight lines that cause thermodynamic compensation. The isoequilibrium temperatures were obtained as -11.4 °C for the zero-order adsorption step and 7.5 °C for the first-order desorption step. As expected, the isokinetic and the isoequilibrium temperatures were very close for each step. The mechanism was concluded to be the same for the ranges of pH and temperature studied. Since all the isokinetic and isoequilibrium temperatures were lower than the working temperature values, the control was concluded to be entropic for all cases. Statistical compensation could be discarded for the zero-order adsorption step but for the first-order desorption step, the compensation was concluded to be as significant as the experimental propagation of errors.

Adsorptive removal of patulin from apple juice via sulfhydryl-terminated magnetic bead-based separation

Patulin is a naturally produced toxin having potential carcinogenic properties. It is mainly produced by species of Penicillium growing on fruits, especially on apples. Detoxification of patulin, therefore, is very important for providing food safety. In this study, sulfhydryl-terminated, silica coated iron oxide beads were investigated as a multi-use sorbents for effective recovery of patulin from apple juice. The effect of beads amount, contact time, pH and temperature were evaluated for high adsorption capacity and the results showed maximum adsorption capacity at a reaction condition of 1.5 mg of beads for 4 h incubation at pH 7.2 and 25 °C. These sorbents were highly effective both in aqueous solution and apple juice with adsorption efficiencies of 99% and 71.25%, respectively. Adsorption process was explained by Langmuir isotherm model with pseudo-second order kinetic model. Thermodynamic parameters described spontaneous adsorption of patulin onto beads with high feasibility and preferences. The reusability of sulfhydryl coated magnetic beads was shown for at least four times without any significant decreases in efficiency. Results showed that this sorbent had potential for removal of patulin from apple juice without any negative effects on final quality parameters, Brix, color, clarity, total sugar and titratable acidity.

Characteristics and Kinetics of Rosin Pentaerythritol Ester via Oxidation Process under Ultraviolet Irradiation

A self-designed reaction device was used as a promising equipment to investigate the oxidation characteristics and kinetics of rosin pentaerythritol ester (RPE) under UV irradiation. Photo-oxidation kinetics and the initial quantum yield (Φ) of RPE were calculated. The initial oxidation product of the photo-oxidation reaction-peroxide was analyzed by iodimetry. The peroxide concentration is related to the light intensity (I) and the temperature (T), and the increasing T and I would destabilize the RPE by accelerating peroxide forming. Photo-oxidation of RPE follows the pseudo first-order reaction kinetics. The relationship between activation energy and logarithm of light intensity (ln I) is linear, and it is expressed as Ea = -4.937ln I + 45.565. Φ was calculated by the photo-oxidation kinetics, and the average value of Φ was 7.19% in the light intensity range of 200⁻800 μW cm^-2. This research can provide fundamental information for application of RPE, and help obtain a better understanding of the stability of rosin esters.