Showing papers by "Hong-Hui Zhuang published in 2022"
TL;DR: In this article , the peptide CCYWDAHRDY was coupled to fluorescent gold nanoclusters (AuNCs), and the fluorescence of synthesized CCYwDAHRdY-AUNCs response to Cu2+ was evaluated.
Abstract: Biomolecule-functionalized fluorescent gold nanocluster (AuNCs) have attracted a lot of attention due to good biocompatibility, stable physicochemical properties and considerable cost advantages. Inappropriate concentration of Cu2+ may cause a variety of diseases. In this study, AuNCs were synthesized in alkaline aqueous solution using bovine serum albumin (BSA) as a template. And then, the peptide CCYWDAHRDY was coupled to AuNCs. Furthermore, the fluorescence of synthesized CCYWDAHRDY-AuNCs response to Cu2+ was evaluated. As the results shown that the CCYWDAHRDY-AuNCs can sensitively detect Cu2+. After adding Cu2+ to the probe system, the fluorescence of the CCYWDAHRDY-AuNCs was quenched. The detection conditions were at pH 6 and 30 °C for 10 min, the linear relationship between Cu2+ concentration and fluorescence intensity were good in the range of 0.1 ~ 4.2 μmol/L. The regression equation was y = - 105.9x + 693.68, the linear correlation coefficient is 0.997, and the minimum detection limit was 52 nmol/L.
7 citations
TL;DR: Curcumin-based aPDT had strong antibacterial activity against S. aureus, which has the potential to remove foodborne pathogens from liquid food.
Abstract: Antimicrobial Photodynamic Treatment (aPDT) is a non-thermal sterilization technology, which can inactivate common foodborne pathogens. In the present study, photodynamic inactivation on Staphylococcus aureus (S. aureus) with different concentrations of curcumin and light dose was evaluated and the mechanisms were also investigated. The results showed that curcumin-based aPDT could inactivate S. aureus cells by 6.9 log CFU/mL in phosphate buffered saline (PBS). Moreover, the modified Gompertz model presented a good fit at the inactivation data of S. aureus. Photodynamic treatment caused cell membrane damage as revealed by analyzing scanning electron microscopy (SEM) images. Leakage of intracellular constituents further indicated that cell membrane permeability was changed. Flow cytometry with double staining demonstrated that cell membrane integrity and the activity of nonspecific esterase were destroyed. Compared with the control group, intracellular reactive oxygen species (ROS) levels caused by photodynamic treatment significantly increased. Furthermore, curcumin-based aPDT reduced S. aureus by 5 log CFU/mL in juices. The color of the juices was also tested using a Chromatic meter, and it was found that b* values were the most markedly influenced by photodynamic treatment. Overall, curcumin-based aPDT had strong antibacterial activity against S. aureus. This approach has the potential to remove foodborne pathogens from liquid food.
4 citations
TL;DR: In this article , the structural variations of tripeptide NCW during absorption, location and distribution of NCW in the membrane, and the effect of the NCW on the properties of membranes during simulation were analyzed to understand the dynamic behavior of the triangular NCW across the membrane.
Abstract: Tripeptide NCW identified in Mizuhopecten yessoensis has been shown to possess in vivo antihypertensive effect. However, the poor understanding of the absorption of NCW across the membrane limits its application. In this study, we have investigated the interaction of NCW with DPPC membrane via 400 ns all-atom molecular dynamic simulation using GROMACS software. The structural variations of NCW during absorption, the location and distribution of NCW in the membrane, and the effect of NCW on the properties of membranes during simulation were analyzed to understand the dynamic behavior of NCW in DPPC membrane system. The results suggested that the structures of NCW were stable during simulation. Further, NCW could bind on the surface of the DPPC membrane and enter the hydrophobic interior of the DPPC membrane. Residue Try played an important role in the absorption of NCW across the membrane. Hydrogen bonds and hydrophobic interactions stabilized the interaction of NCW with the membrane. All the above studies analyzed the interaction mechanism between NCW and DPPC membranes at the atomic level and laid the foundation for further transmembrane studies of NCW.
TL;DR: In this paper , a composite photoensitiser was used to control the growth of Staphylococcus aureus, which provided a novel approach for raw sterilisation to maintain food safety.
Abstract: Antimicrobial photodynamic therapy (aPDT) is an effective method in the field of sterilisation. Singlet oxygen (1O2) is an important substance in photodynamic sterilisation that needs to be detected. It involves energy transfer from an excited photosensitiser to surrounding oxygen molecules to produce cytotoxic 1O2 species, a process termed as type II reaction. Traditional photodynamic sterilisation for fresh produce generally involves only a single photosensitiser and uses nanoemulsions coating to make the photosensitiser work better. This allows the emulsion to produce only a limited amount of reactive oxygen species (ROS) in the presence of light, such that the bactericidal effect is limited. We have innovatively compounded two photosensitisers and stored them as nanoemulsions. The composite photosensitiser produces relatively higher ROS and the nanoemulsions have good stability as well as rheological properties, and the photosensitisers are well coated in the emulsions. In summary, nanoemulsions based on composite photosensitisers showed synergistic activity in controlling the growth of Staphylococcus aureus, which provides a novel approach for raw sterilisation to maintain food safety.