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Self-assembly of misfolded proteins into ordered fibrillar aggregates known as amyloid results in various human diseases. However, more and more proteins, whether in human body or in food, have been found to be able to form amyloid fibrils with in-depth researches. As a model protein for amyloid research, lysozyme has always been the focus of research in various fields. Firstly, the formation mechanisms of amyloid fibrils are discussed concisely. Researches on the regulation of lysozyme amyloid fibrils are helpful to find suitable therapeutic drugs and unfriendly substances. And this review article summarizes a number of exogenous substances including small molecules, nanoparticles, macromolecules, and polymers. Small molecules are mainly connected to lysozyme through hydrophobic interaction, electrostatic interaction, π-π interaction, van der Waals force and hydrogen bond. Nanoparticles inhibit the formation of amyloid fibers by stabilizing lysozyme and fixing β-sheet. Besides, the applications of lysozyme amyloid fibrils in food-related fields are considered furtherly due to outstanding physical and mechanical properties. Nevertheless, the potential health threats are still worthy of our attention. Finally, we also give suggestions and opinions on the future research direction of lysozyme amyloid fibrils.

Titanium dioxide (TiO2), as a representative of metallic oxides, is widely used as food additive to serve as coloring or antibacterial packaging fortifier. However, in recent years, the potential hazards of nano-sized TiO2 food additives to human beings is still in doubt. In this work, we systematically studied the interactions between three sizes of TiO2 particles and the cell membrane systems with confocal laser scanning microscopy. We used both giant unilamellar vesicles and human colon cancer cells to mimic actual cell membrane systems. The results demonstrate the strong effect of particle size on membrane disruption and leakage behaviors. Among the three sizes of TiO2 nanoparticles (NPs) used in this work, the TiO2 NPs with the size of 110-300 nm are safe. In contrast, NPs with the size of 10-30 nm and 50-100 nm will cause the rupture and leakage of cell membranes. These indicates that the cytotoxicity of nano-sized TiO2 particles increases with the decrease of particle sizes. In addition, it is found that the size effect of TiO2 particles further depends on the membrane charge state. Simulations were also introduced to understand the results. This study would provide a theoretical basis for the production designing and safety standard of metallic oxide food additives.

At present, nanoplastics have been detected in food and the environment, but they have serious impacts on the human body. As one of the typical representatives of nanoplastics, polystyrene (PS) is generally used as an experimental object. Few studies found that PS could modulate the formation of amyloid fibrils, leading to the occurrence of diseases. However, its submicron-scale effects remain elusive. Thus, this study aimed to explore the interaction between PS of particle size 100-500 nm and hen egg-white lysozyme (HEWL). The results showed that PS of size 400 nm markedly promoted the primary nucleation step of amyloid fibril formation, and fibrils had more small fragments compared with PS of size 100 nm in the control and sample groups. PS of larger particle size changed the spatial structure of HEWL significantly. This study analyzed the experimental results from the perspective of protein corona and thermodynamics. The study confirmed that PS was able to form protein corona with HEWL in the initial stage, which was mainly driven by hydrophobic interactions. More importantly, the interface and junction of the protein corona were the main sites for the formation of amyloid fibrils. This study highlighted the role of submicron particle size and discussed the toxic effects of nanoparticles.

Bacterial residue is one of the main causes of diseases and economic losses. In recent years, microfabrication technology has inspired the introduction of microstructures on the surfaces of relevant materials to provide antibacterial effects. This antibacterial method has become a popular research topic due to its safety, effectiveness, and stability. However, its exact mechanism is still under debate. In this study, normal force was introduced to bacteria on GaN nanopillars to investigate the mechanical sterilization effects and a computer simulation was conducted. The results show that the normal force induces highly efficient mechanical sterilization of the nanopillars, and their surfaces impede the attachment of bacteria. This study provides insights into the antibacterial effect of nanopillars and offers a potential antibacterial tool with high efficiency.

Nowadays, the widespread distribution of microplastics (MPs) in various foods has received much attention. In this study, eggs were purchased as samples from local supermarkets to detect and analyze the presence of MPs. The digestion method was optimized for eggs to better isolate MPs, which proved MPs indeed exist in eggs, and the average content was 11.67 ± 3.98 particles/egg. The shape and size range of most MPs were spherical and 50-100 μm. The infrared results showed that the main type of MPs in eggs was polyethylene. The number of MPs in egg yolk was higher than that in egg white, and there was no significant change after cooking. In addition, the daily human intake of MPs was estimated. Therefore, the results of this study provided a background for the current status and pollution of MPs in eggs, and proposed the necessary control and preventive measures to avoid this situation.

In modern society, plastics also play an indispensable role in people's lives due to their various excellent properties. However, when these plastic products are discarded after being used, after being subjected to external influences, they will continue to be worn, damaged and degraded into micro- and nano-scale plastics, which are microplastics and nanoplastics (M/NPs). Although people's attention has been paid to M/NPs at present, the focus is still mainly on the detection and hazard of M/NPs, and how to remove M/NPs is relatively less popular. This review was written in order to draw the attention of more researchers to remove M/NPs. This review first briefly introduces the research background of M/NPs, and also shows the main analytical methods currently used for qualitative and quantitative M/NPs. Then, most of the current literature on the removal of M/NPs was collected, and they were classified, summarized, and introduced according to the classification of physical, physicochemical, and biological methods. The advantages and disadvantages of various methods are summarized, and they are also compared, which can help more researchers choose the appropriate method for research. In addition, the application scenarios of these methods are briefly introduced. Finally, some future research directions are proposed for the current research status of M/NPs removal. It is hoped that this will further promote the development on the method of removing M/NPs.

As current concerns about food safety issues around the world are still relatively serious, more and more food safety issues have become the focus of people's attention. What's more serious is that environmental pollution and changes in human lifestyles have also led to the emergence of contaminants in food, microplastics (MPs) and nanoplastics (NPs) being typical representatives. MPs and NPs (M/NPs) in food are gradually becoming recognized by regulatory authorities and the public. Most published reviews on M/NPs have been focused on the environmental ecosystems. In those papers, it is only sporadically mentioned that M/NPs can also appear in food. As far as we know, there has not been a systematic review of the pollution and existing status of M/NPs in food. This Review focuses on the harmfulness of M/NPs, the ways in which M/NPs contaminate food, the residual amount of M/NPs in food, and the current analysis and detection methods for M/NPs in food. Current analysis and detection methods have problems such as being time-consuming, involving cumbersome operation, and giving poor accuracy. In the future, it will be necessary to increase the research on methods for efficient and sensitive separation and detection of M/NPs in food. Finally, it is hoped that this Review will arouse more people's awareness of and attention to the seriousness of M/NPs in food.

A simple dual-colour fluorescent nanoprobe has been designed composed of blue and yellow emission carbon quantum dots (CQDs). This system is inexpensive and easy to operate and was successfully employed for on-site measurements based on a smartphone app. The designed nanoprobe exhibited increased selectivity for Cr(VI), leading to a double stable response of the two CQDs. The dual-emission nanoprobe showed blue-violet fluorescence upon UV irradiation, and the fluorescent emission peaks were located at 418 nm and 552 nm. The blue light emission of CQDs was quenched with increasing Cr(VI) concentration due to the inner filter effect, whereas the yellow light emission was enhanced due to the aggregation-induced emission effect. The different responses of the dual emissions to Cr(VI) resulted in a fluorescent colour variation, thus enabling facile macroscopic visualization. With a smartphone, the change in the fluorescence colour could be observed more apparently than that of a single fluorescence nanoprobe, and the response increased linearly so that the nanoprobe could be applied to instantaneous measurements. Furthermore, the dual-emission nanoprobe was successfully employed for analysing food and water samples. Accurate concentrations were obtained by constructing a calibration plot using a fluorescence spectrometer and a smartphone app; the recoveries were 81.6% to 107.7%, and the relative standard deviation was below 3.6%. Therefore, this smartphone-integrated dual-emission detection system is promising as a new portable method for the on-site measurement of Cr(VI) ions.

In this study, the pine nut (Pinus yunnanensis Franch.) protein was hydrolyzed by alkaline protease and trypsin to prepare pine nut protein hydrolysate (PNPH). The chemical, intracellular and in vivo antioxidant capacity of PNPH were evaluated. PNPH owned the ability of scavenging free radicals, and it could protect the HepG2 cells from oxidative damage by preserving cell viability. Moreover, PNPH could reduce the malondialdehyde (MDA) content and improved the superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in serum, heart and liver of aging mice induced by D-galactose. Further, the PNPH was stepwise purified and identified, and 15 peptides were identified from purified fraction in PNPH. The three-dimension structures of identified peptides were predicted. Among all identified peptides, peptide 3, 7, 8 and 11 were presumed to possess good antioxidant activity. Overall, PNPH and purified peptides isolated from PNPH have potential application prospects in the field of natural antioxidants and anti-aging functional foods.

A simple dual-colour fluorescent nanoprobe has been designed composed of blue and yellow emission carbon quantum dots (CQDs). This system is inexpensive and easy to operate and was successfully employed for on-site measurements based on a smartphone app. The designed nanoprobe exhibited increased selectivity for Cr(VI), leading to a double stable response of the two CQDs. The dual-emission nanoprobe showed blue-violet fluorescence upon UV irradiation, and the fluorescent emission peaks were located at 418 nm and 552 nm. The blue light emission of CQDs was quenched with increasing Cr(VI) concentration due to the inner filter effect, whereas the yellow light emission was enhanced due to the aggregation-induced emission effect. The different responses of the dual emissions to Cr(VI) resulted in a fluorescent colour variation, thus enabling facile macroscopic visualization. With a smartphone, the change in the fluorescence colour could be observed more apparently than that of a single fluorescence nanoprobe, and the response increased linearly so that the nanoprobe could be applied to instantaneous measurements. Furthermore, the dual-emission nanoprobe was successfully employed for analysing food and water samples. Accurate concentrations were obtained by constructing a calibration plot using a fluorescence spectrometer and a smartphone app; the recoveries were 81.6% to 107.7%, and the relative standard deviation was below 3.6%. Therefore, this smartphone-integrated dual-emission detection system is promising as a new portable method for the on-site measurement of Cr(VI) ions. * Y-CQDs: yellow emission carbon quantum dots. B-CQDs: blue emission carbon quantum dots. B/Y-CQDs: a mixture of B-CQDs and Y-CQDs.

The development of an effective and convenient pretreatment technology for the removal of contaminants from drinking water is crucial to public health. In this study, a novel durian-shaped magnetic porous Fe3O4@MIL-100(Fe) composite was prepared by solvothermal method for the removal of bisphenol A(BPA) from drinking water. Various techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and nitrogen adsorption–desorption were employed to characterize the composite. The results showed that the Fe3O4@MIL-100(Fe) composite possessed a core–shell structure with a specific surface area of 365.42 m2 g−1 and a BPA adsorption capacity of more than 90 mg g−1. In addition, the Fe3O4@MIL-100(Fe) composite exhibited good reusability, with a retained adsorption rate of 87% and no significant loss in adsorption capacity after five cycles. Under optimal conditions, this material showed good linear adsorption of BPA from drinking water in the 0 to 50 mg L-1 concentration range. After selective adsorption, BPA was detected at a wavelength of 276 nm by UV/vis spectrophotometry with a detection limit of 5000 ng L-1.

Bacterial adhesion on medical instruments’ and food packages’ surfaces causes implanted infections, food spoilage and human disease, therefore attracts a lot of attention in the field of medical and food applications. Containing the initial adhesion of bacteria on the surface of the material plays an important role in reducing potential safety hazards. In this work, we investigate the influence of silver ion implantation with different doses on the antibacterial performance of the polyethylene (PE) films. It is found out that silver ion implantation will not color the PE films but can improve their surface hydrophilicity. The silver-implanted PE films show the ability to inhibit bacterial adhesion and have the bactericidal effect, both of which can be improved with increasing silver implantation dose. This method also proves relatively safe, because the silver ions are relatively stable. The results will introduce potential applications for ion implantation in the food packing and food accessible materials.

Nano-titanium dioxide (nano-TiO2) and litchi peel extract (LPE) were added to chitosan (CS) matrix to develop a novel active packaging film and watercored apple coating. The addition of nano-TiO2 and/or LPE enhanced mechanical strength, water vapor barrier properties, and thermal stability of CS-based films. The total phenolic content and antioxidant capacity of the films were enhanced by LPE incorporation. Viscosity and wettability of the coating solutions and their impact on the storage quality of watercored Fuji apples at 0 ± 1℃ for 180 d were investigated. Coating treatment significantly inhibited respiration rate, weight loss, and softening. Polyphenol oxidase activity, electrolyte leakage and malondialdehyde accumulation were inhibited by coating treatment. A CS + TiO2+LPE coating was the most effective treatment for maintaining cold storage quality of watercored apples. This combination presents promising applications as an active food packaging film and fruit preservation coating.