Adsorptive removal of patulin from apple juice using Ca-alginate-activated carbon beads

Patulin-degrading enzymes sources, structures, and mechanisms: A review

Patulin (PAT), a fungal secondary metabolite with multiple toxicities, is an unavoidable contaminant in fruit and vegetable processing, posing potential health risks to consumers and causing significant economic losses to the global food industry. Traditional control strategies, such as physical and chemical methods, face several challenges, including low efficiency, high costs, and unverified safety. In contrast, microbial degradation of patulin is considered a more efficient and environmentally friendly approach, which has become a popular research focus. However, there is still insufficient research on the key degradation enzymes involved in microorganisms. Therefore, this review comprehensively summarizes recent research progress on the biological degradation of patulin, with a focus on microbial species capable of degrading patulin, the degradation enzymes they express, potential degradation mechanisms, and the toxicity of degradation products, while providing prospects for future research. It offers valuable insights for controlling patulin in food and stimulates further investigation. Ultimately, this review aims to promote the development of efficient and eco-friendly methods to mitigate patulin contamination in fruits and vegetables.

Application of natural fining agents to clarify fruit juices

The consumption of fruit juices has been increasingly growing all over the world. The clarification process is considered as one of the most important stages in fruit juice production, which can provide the products with desired clear visual appearance. Nowadays, the tendency of consumers to use the natural-clarified fruit juices encourages the researchers to allocate much attention on utilization of natural clarifying agents to clarify different fruit juices. This review article has first introduced the most frequent causes of turbidity in fruit juices including polysaccharides (i.e., cellulose, hemicelluloses, lignin, starch, and pectic substances), proteins and polyphenols (especially tannins) as well as their removal mechanisms. After that, a comprehensive summary of research on natural fining agents, including clay minerals, polysaccharides, proteins, enzymes (free and immobilized forms), and activated carbon is provided with a focus on their application in the juice clarification process. The chemical composition of natural substances, their efficiency on reduction of turbidity-causing compounds and the changes in properties of clarified juices such as turbidity (clarity), total phenolic content, total anthocyanins, viscosity, and sensory evaluation followed by their stability during the storage have been deeply discussed.

Electrostatic adsorption and removal mechanism of ochratoxin A in wine via a positively charged nano-MgO microporous ceramic membrane

Ochratoxin A (OTA) is a very important mycotoxin. However, there are few studies on the removal of OTA in wine because of the great influence on product quality and difficulty in practical application. A nano-MgO-modified diatomite ceramic membrane (MCM) with a high positive charge was prepared and applied to remove OTA in wine. The isotherm adsorption between the positively charged membrane and OTA was in accordance with the Langmuir model, with a maximum adsorption capacity of 806 ng/g at 25 °C. All of the changes in adsorption enthalpy (ΔH), adsorption free energy (ΔG) and adsorption entropy (ΔS) were negative, which indicated that the combination of nano-MgO MCM and OTA was a spontaneous exothermic and nonspecific physical adsorption process. The concentrations of OTA in adsorption-treated wines were lower than 2 μg/kg, and the removal rates exceeded 92%. After OTA removal, the composition of wines was preserved to some extent.

An effective and recyclable decolorization method for polysaccharides from Isaria cicadae Miquel by magnetic chitosan microspheres

The purpose of this research was to develop an efficient and non-destructive method for decolorizing of polysaccharides extracted from Isaria cicadae Miquel by magnetic chitosan microspheres (MCM). The optimum decolorization parameters were achieved by response surface methodology as follows: the MCM amount was 8.0%, the adsorption temperature was 48 °C, the adsorption time was 82 min and the pH was 7. Under these optimal conditions, the D _r%, R _r%, and K _c were 90.31 ± 0.12%, 95.40 ± 0.11% and 19.66 ± 0.49, respectively. MCM adsorption of pigment molecules was a spontaneous and endothermic process that could be fitted with the pseudo-second-order equation and the Freundlich equation. Besides, the adsorption mechanism could be controlled by multiple-diffusion steps, including film diffusion and intra-particle diffusion. Furthermore, MCM is a recyclable material. Adsorption with MCM is a promising method to remove pigment molecules of polysaccharide, it may replace the traditional decolorization method.

Adsorption Mechanism of Patulin from Apple Juice by Inactivated Lactic Acid Bacteria Isolated from Kefir Grains

In the food industry, microbiological safety is a major concern. Mycotoxin patulin represents a potential health hazard, as it is heat-resistant and may develop at any stage during the food chain, especially in apple-based products, leading to severe effects on human health, poor quality products, and profit reductions. The target of the study was to identify and characterize an excellent adsorbent to remove patulin from apple juice efficiently and to assess its adsorption mechanism. To prevent juice fermentation and/or contamination, autoclaving was involved to inactivate bacteria before the adsorption process. The HPLC (high-performance liquid chromatography) outcome proved that all isolated strains from kefir grains could reduce patulin from apple juice. A high removal of 93% was found for juice having a 4.6 pH, 15° Brix, and patulin concentration of 100 μg/L by Lactobacillus kefiranofacien, named JKSP109, which was morphologically the smoothest and biggest of all isolates in terms of cell wall volume and surface area characterized by SEM (Scanning electron microscopy) and TEM (transmission electron microscopy). C=O, OH, C–H, and N–O were the main functional groups engaged in patulin adsorption indicated by FTIR (Fourier transform–infrared). E-nose (electronic nose) was performed to evaluate the aroma quality of the juices. PCA (Principal component analysis) results showed that no significant changes occurred between control and treated juice.

Prevention and detoxification of patulin in apple and its products: A review

Patulin-producing fungi pose an unavoidable problem for apple and its product quality, thereby threatening human and/or animal health. Studies on controlling the patulin-producing fungal growth and patulin contamination in apple and its products by physical methods, chemical fungicides, and biological methods have been performed for decades, but patulin contamination has not been addressed. Here, the important of studying regulation mechanism of patulin production in apple at the protein expression and metabolism levels is proposed, which will facilitate the development of controlling patulin production by using physical, chemical, and biological methods. Furthermore, the advantages or disadvantages and effects or mechanisms of using physical, chemical, biological methods to control the decay caused by Penicillium expansum and to remove patulin in food was discussed. The development of physical methods to remove patulin depends on the development of special equipment. Chemical methods are economical and efficient, if we have ensured that there are no unknown reactions or toxic by-products by using these chemicals. The biological method not only effectively controls the decay caused by Penicillium espansum, but also removes the toxins that already exist in the food. Degradation of patulin by microorganisms or biodegradation enzymes is an efficient and promising method to remove patulin in food if the microorganisms used and the degradation products are completely non-toxic.

Synthesis of triethylene tetramine-modified water-insoluble corn flour caged in magnetic chitosan resin and its adsorption application for removal of patulin from apple juice

In this study, triethylene tetramine-modified water-insoluble corn flour caged in magnetic chitosan resin (TETA-WICF/MCR) was firstly prepared, which indicates novel aspects for immobilization and chemically modification of mycotoxin adsorbents. The TETA-WICF/MCR was characterized using zoom stereo microscope, scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometer (XRD), and magnetic separation performance analysis. Experimental results confirmed successful layer by layer modification of chitosan, biosorbent water-insoluble corn flour (WICF), TETA onto the surface of magnetic beads. The mean diameter of the TETA-WICF/MCR was 2.63 mm with good magnetic-responsive ability. Subsequently, the adsorption performance of the TETA-WICF/MCR obtained toward patulin was assessed in batch adsorption system and the results demonstrated that the adsorption process was strongly depended on adsorbent dosage, contact time, temperature, and initial patulin concentration. The results of SEM images and FTIR analysis showed obvious changes in the porous structure of TETA-WICF/MCR after adsorbing patulin, and -NH₂ and -OH groups were predominantly involved in the adsorption of patulin. Furthermore, the adsorption kinetics followed the mechanism of pseudo-second-order model, and equilibrium data were well fitted in the Freundlich isotherm model. It was also found that the TETA-WICF/MCR had good reusability without any adverse changes in apple juice. PRACTICAL APPLICATION: Patulin is a regulated toxin biosynthesized by certain fungi that contaminate agricultural commodities, such as fruits, juices, and other beverages. Several approaches have been studied to reduce patulin levels in apple juice and other aqueous systems. There is need for more low-cost and eco-friendly adsorbent capable of detoxifying patulin contaminated. In this sense, triethylene tetramine-modified water-insoluble corn flour caged in magnetic chitosan resin (TETA-WICF/MCR) was first prepared and exhibits easy solid-liquid separation and high adsorption capacity for removing patulin from contaminated apple juice.

Highly efficient and cost-effective removal of patulin from apple juice by surface engineering of diatomite with sulfur-functionalized graphene oxide

Patulin (PAT) contamination of apple juice leads to a serious food safety issue. Developing an excellent adsorbent to efficiently remove PAT is more desirable. Herein, a cost-effective and efficient adsorbent (GO-SH/diatomite) with abundant active sites was successfully fabricated via surface engineering of diatomite with sulfur-functionalized graphene oxide (GO-SH) nanosheets, which exhibited excellent selective adsorption capacity toward PAT. The adsorption behavior, adsorption mechanism, stability and cytotoxicity were investigated by systematic studies. The adsorption results showed that its maximum adsorption capacity was 10.68 μg/mg. Moreover, attributed to the specific interaction between PAT and thiol group, more than 90% of PAT was removed from apple juice without any juice quality deterioration. Importantly, the risk of food safety issue of apple juice caused by residual GO-SH/diatomite was negligible due to the properties of easy removal and excellent biocompatibility, which guaranteed its potential application in apple juice industry for PAT removal.

Mycotoxin patulin in food matrices: occurrence and its biological degradation strategies

Patulin is a mycotoxin produced by a number of filamentous fungal species. It is a polyketide secondary metabolite which can gravely cause human health problems and food safety issues. This review deals with the occurrence of patulin in major food commodities from 2008 to date, including historical aspects, source, occurrence, regulatory limits and its toxicity. Most importantly, an overview of the recent research progress about the biodegradation strategies for contaminated food matrices is provided. The physical and chemical approaches have some drawbacks such as safety issues, possible losses in the nutritional quality, chemical hazards, limited efficacy, and high cost. The biological decontamination based on elimination or degradation of patulin using yeast, bacteria, and fungi has shown good results and it seems to be attractive since it works under mild and environment-friendly conditions. Further studies are needed to make clear the detoxification pathways by available potential biosorbents and to determine the practical applications of these methods at a commercial level to remove patulin from food products with special reference to their effects on sensory characteristics of foods.

Controlled Release of Peppermint Oil from Paraffin-Coated Activated Carbon Contained in Sachets to Inhibit Mold Growth During Long Term Storage of Brown Rice

The aim of the study was to control the release of peppermint oil (700 µL/L) by coating activated carbon (AC) contained in sachets with different solutions (tapioca starch, corn starch, gelatine, carnauba, paraffin, and mixed carnauba-paraffin) for inhibiting the growth of Aspergillus flavus on brown rice (BR). Paraffin-coated AC with adsorbed peppermint oil was then applied to extend the shelf life of BR during long-term storage (60 days) at 30 ± 2 °C. The mechanism of peppermint oil vapor release in this system was also studied using GC-MS. The result revealed that paraffin-coated AC with adsorbed peppermint oil present in sachets showed the highest antifungal activity against A. flavus growing on the surface of BR. In addition, paraffin-coated AC with adsorbed peppermint oil could prolong the shelf life of BR from 10 days (control) to at least 60 days under tropical climatic conditions. Moreover, storage of BR in the presence of sachets containing paraffin-coated AC with adsorbed peppermint oil at a concentration of 700 µL/L revealed no significant effects on major rice quality-related factors, such as moisture content, color, water uptake percentage, and gelatinization temperature. Peppermint oil component analysis by GC-MS indicated that paraffin could trap some minor components of peppermint oil and allow the major components such as menthone, menthol, and alpha-pinene, which are compounds that play an important role in mold growth inhibition, to be exposed to air. Thus, this research demonstrated the potential of paraffin-coated AC containing adsorbed peppermint oil for controlling the growth of molds during prolonged rice storage. PRACTICAL APPLICATION: Paraffin-coated activated carbon with adsorbed peppermint oil has the potential to be commercially applied to brown rice grains for facilitating long-term storage. This technique is beneficial for avoiding the occurrence of negative sensorial factors when peppermint oil vapors are used. This process is interesting and easy to apply during large-scale implementation of a rice storage system.

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.

Dynamic High-Pressure Microfluidization Treatment of Rice Bran: Effect on Pb(II) Ions Adsorption In Vitro

Insoluble dietary fiber from rice bran (RBIDF) was treated with dynamic high-pressure microfluidization (DHPM). The influence of pressure on the adsorption of Pb(II) capacity of RBIDF was explored in a simulation of the gastrointestinal environment. RBIDF (pH 7.0) displayed the maximal binding capacity (420.74 ± 13.12 μmol/g), at the level of 150 MPa, which was as 1.36 times as the untreated sample. DHPM-treated RBIDF demonstrated a higher ability to adsorb cholesterol and sodium cholate. Meanwhile, the treatment changed the morphology but did not alter the primary structure. The adsorption capacity is linear to the physicochemical properties of the total negative charges. The adsorption kinetics fit the pseudo-second-order model, Pb(II) adsorption mainly occur on the surface of the fiber particulate, this process includes natural physical adsorption and chemical reaction. This study provides a feasible approach for improving the adsorption capacity of RBIDF, especially the adsorption of Pb(II).

PRACTICAL APPLICATION

Dynamic high-pressure microfluidization can modify biomass adsorption materials effectively as a physically modification. The pretreatment dietary fiber can be used as a low-cost absorbing heavy metal biosorbent, and can be develop the functional food ingredients in the food industry.

Effective Adsorption of Patulin from Apple Juice by Using Non-Cytotoxic Heat-Inactivated Cells and Spores of Alicyclobacillus Strains

Patulin (PAT) is a major threat to many food products, especially apple and apple products, causing human health risks and economic losses. The aim of this study was to remove PAT from apple juice by using the heat-inactivated (HI) cells and spores of seven Alicyclobacillus strains under controlled conditions. The HI cells and spores of seven strains adsorbed PAT effectively, and the HI cells and spores of Alicyclobacillus acidocaldarius DSM 451 (A51) showed maximum PAT adsorption capacity of up to 12.621 μg/g by HI cells and 11.751 μg/g by HI spores at 30 °C and pH 4.0 for 24 h. Moreover, the PAT adsorption process followed the pseudo-first order kinetic model and the Freundlich isotherm model; thermodynamic parameters revealed that PAT adsorption is a spontaneous exothermic physisorption process. The results also indicated that PAT adsorption is strain-specific. The HI cells and spores of Alicyclobacillus strains are non-cytotoxic, and the bioadsorption of PAT did not affect the quality of the juice. Furthermore, the cell wall surface plays an important role in the adsorption process.

Patulin removal from apple juice using a novel cysteine-functionalized metal-organic framework adsorbent

Patulin (PAT) is one of the most common toxic contaminants of apple juice, which causes severe food safety issues throughout the apple industry. In order to remove PAT efficiently, a metal-organic framework-based adsorbent (UiO-66(NH₂)@Au-Cys) was successfully synthesized and used for PAT removal from juice-pH simulation solution and real apple juice. Batch adsorption experiments were systematically performed to study the adsorption behavior for PAT. The results showed that adsorption process could be well described by the Pseudo-second order model and Freundlich isotherm model. The maximum adsorption capacity (4.38 µg/mg) was 10 times higher than the microbe-based biosorbents. Thermodynamic investigation demonstrated that adsorption process was spontaneous and endothermic. Furthermore, no marked cytotoxicity on NIH 3T3 cell lines was observed when the concentration of the adsorbent was lower than 10 μg/mL. Therefore, UiO-66(NH₂)@Au-Cys is a potential adsorbent for PAT removal from apple juice with little quality changes.

Biocontrol Agents Increase the Specific Rate of Patulin Production by Penicillium expansum but Decrease the Disease and Total Patulin Contamination of Apples

Synthetic fungicides are commonly employed for the control of postharvest diseases of fruits. However, due to health concerns about the use of these chemicals, alternative control methods including biocontrol based on antagonistic yeasts are gaining in popularity. In this study, we investigated the effects of two biocontrol yeasts, Rhodotorula mucilaginosa strain 3617 and Rhodotorula kratochvilovae strain LS11, on blue mold and patulin (PAT) contamination caused by Penicillium expansum strains PY and FS7 in artificially inoculated Fuji apples stored at 20°C for 9 days. To correlate the development of the P. expansum strains in yeast-treated and untreated apples with PAT production, we quantified their biomass in the infected fruits using a recently published quantitative real-time polymerase chain reaction method based on specific primers for patF, a gene from P. expansum that is involved in PAT biosynthesis. Both yeasts significantly reduced the disease incidence caused by the two strains of P. expansum up to 5–7 days of incubation, and lowered their biomass and the progression of symptoms up to 9 days. Interestingly, both yeasts strains increased the rate of PAT production (expressed as ng patulin/μg fungal DNA) by the two pathogenic strains. Nevertheless, both biocontrol agents reduced the total PAT contamination, especially in the case of P. expansum strain FS7, the higher PAT producer of the two tested P. expansum strains. Comparing between the yeast strains, R. kratochvilovae LS11 was more effective than R. mucilaginosa 3617 for the control of P. expansum.

Patulin adsorption of a superior microorganism strain with low flavour-affection of kiwi fruit juice

The aim of this study was to isolate a microbial strain with higher patulin adsorption capability and lower flavour-affection on kiwi fruit juice, and study patulin adsorption behaviour effects on cell morphology and adsorption kinetics. Electronic-nose and physicochemical analysis methods were combined to evaluate the flavour and quality of treated kiwi fruit juice. The results showed that yeasts had a good performance on biomass, patulin adsorption and flavour maintenance. Besides, patulin adsorption behaviour and kinetic study of yeast strain N-10 was investigated, the results showed that patulin adsorption capability was influenced by cell morphology, its adsorption behaviour followed pseudo-first-order reaction kinetics, and equilibrium experiments fit the Langmuir isotherm model. The investigation revealed that patulin adsorption is a spontaneous endothermic physic-sorption behaviour. During adsorption, patulin moved from the liquid to the adsorbent surface and the capability of adsorbents was associated with their cell surface morphology. This study provides a basis for the selection of strains with improved patulin adsorption from kiwi fruit juice and provides the experimental foundation and theoretical basis for future studies of patulin adsorption in fruit juice, it has great potential application for the control of patulin in the juice processing industry.