UV Treatment Research Articles

Comparison of DNA stability and its related genes of neurons derived from induced pluripotent stem cells and primary retinal neurons.

Maintaining DNA stability in induced pluripotent stem cells (iPSCs) and iPSCs-derived neurons is a challenge in their clinical application. In the present study, we compared DNA stability between primary retinal neurons and differentiated neurons. We found that the basal level of γ-H2AX phosphorylation, a specific marker of DNA breaks, was notably higher (~26-folds) in human iPSCs compared to iPSCs-derived neurons. However, iPSCs-derived neurons are more sensitive to UV treatment compared to primary rat retinal neurons (postnatal Day 1). UV treatment induced a significantly decreasing in the cell viability of iPSCs-derived neurons by ~76.1%, whereas ~20.8% in primary retinal neurons. After analyzing the expression levels of genes involved in DNA stability, such as Brca1, Ligase IV, Ku80, and Mre11, we found that Ku80 and its heterodimeric partner, Ku70 were positive in iPSCs-derived neurons. However, both Ku80 and Ku70 are not expressed in primary retinal neurons and cerebellar neurons. Similarly, both Ku80 and Ku70 are also expressed in 3D retinal organoids from human embryonic stem cells (ESCs), except for a few Map2-negative cells and the hyaloid vessels of mice E12.5 retinas. Hence, Ku80, and Ku70 are specifically expressed in stem cell-derived neurons. Moreover, using the Ku80 inhibitor Compound L, our data showed that Ku80 promotes the DNA stability and cell viability of iPSCs-derived neurons. Thus, our results demonstrated that iPSCs-, ESCs-derived neurons have specific characteristics of DNA stability. This study provides new insights into the neural differentiation of stem cells but might also warrant the future clinical application of stem cells in neurodegenerative diseases.

System and eco-material design based on slow-release ferrate(vi) combined with ultrasound for ballast water treatment

Abstract Background The problem of ballast water is caused by microorganisms. The solution to solve this problem is ballast water disinfection. Until the recent day, there have not been many practical solutions. Usually, ozone, chlorine, and UV treatments were used for disinfection. However, these methods still have many weaknesses in treating ballast water. Methods The ferrate(vi) system proposed in this paper is liquid ferrate(vi) produced on-site using a slow-released system and combined with ultrasound. This paper investigated the optimum time to produce liquid ferrate(vi), pH, and temperature. Results The optimum synthesis time has been observed to be 10 min with the produced ferrate(vi) of 42,000 ppm. The optimal pH and temperature to make ballast water harmless have been observed to be the neutral pH condition at 25°C, respectively. The design of ballast water treatment using ferrate(vi) combined with ultrasound has also been proposed in this paper. Conclusions Ferrate(vi), as the primary material in ballast water treatment, has been successfully synthesized. The process of ballast water treatment using ferrate(vi) combined with ultrasound can be performed automatically using a time sensor and a mass sensor. With the proposed design, it can be a promising solution to solve the problems related to ballast water.

Polyamide thin films with nanochannel networks synthesized at the liquid–gas interface for water purification

An important challenge concerning thin-film composite (TFC) membranes in brine treatment is to increase their water permeance while maintaining salt rejection for desalination performance. Structural control of polyamide (PA) thin films is a key factor in improving the desalination performance. In this study, we employed a Langmuir–Schaefer technique to fabricate PA Langmuir monolayers by interfacial polymerization of m-phenylenediamine and trimesoyl chloride at the liquid–gas interface and deposition on polysulfone supports. This technique allows the fabrication of nanoscale-controlled PA multilayers (2.3 nm per layer) with a nano-channeled structure through repeated deposition. The nanochannels of PA thin-film multilayers were clarified using the neutron reflectivity technique. UV treatment facilitates the maintenance of water-permeable sites in the nanochannels, which increases the water permeance up to 203% without loss of salt rejection performance.

Systematic analysis and expression profiles of TCP gene family in Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) revealed the potential function of FtTCP15 and FtTCP18 in response to abiotic stress

BackgroundAs transcription factors, the TCP genes are considered to be promising targets for crop enhancement for their responses to abiotic stresses. However, information on the systematic characterization and functional expression profiles under abiotic stress of TCPs in Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn.) is limited.ResultsIn this study, we identified 26 FtTCPs and named them according to their position on the chromosomes. Phylogenetic tree, gene structure, duplication events, and cis-acting elements were further studied and syntenic analysis was conducted to explore the bioinformatic traits of the FtTCP gene family. Subsequently, 12 FtTCP genes were selected for expression analysis under cold, dark, heat, salt, UV, and waterlogging (WL) treatments by qRT-PCR. The spatio-temporal specificity, correlation analysis of gene expression levels and interaction network prediction revealed the potential function of FtTCP15 and FtTCP18 in response to abiotic stresses. Moreover, subcellular localization confirmed that FtTCP15 and FtTCP18 localized in the nucleus function as transcription factors.ConclusionsIn this research, 26 TCP genes were identified in Tartary buckwheat, and their structures and functions have been systematically explored. Our results reveal that the FtTCP15 and FtTCP18 have special cis-elements in response to abiotic stress and conserved nature in evolution, indicating they could be promising candidates for further functional verification under multiple abiotic stresses.

Rare UV-resistant cells in clonal populations of Escherichia coli

Water disinfection is one of the most important applications of ultraviolet light-emitting diodes (UV-LEDs), though bacterial regrowth remains a serious problem. In this study, we showed that UV-resistant cells, though rare, exist in an Escherichia coli clonal population. The UV-resistance of stationary phase cells was higher than that of exponential phase cells. Regrowth cell populations showed identical UV sensitivity before and after UV treatment, indicating that UV resistance is not acquired genetically, but is generated stochastically. The characteristics of these UV-resistant cells are similar to those of non-heritable antibiotic-resistant cells, termed persisters. The induction of persister formation increased the number of viable cells after UV treatment. The toxin-antitoxin system gene hipA (high persistence A) is a key factor in persister cell formation. We observed that hipA was strongly expressed in the stationary phase cells, while regrowth cells after UV treatment lost hipA expression, suggesting that the regrowth cells lost their persistence. Compared to UV batch radiation, we demonstrated that intermittent UV irradiation, which included the induction of regrowth between UV treatments, significantly reduced the number of viable E. coli cells.

Prevention and practical strategies to control mycotoxins in the wheat and maize chain

Within this study, food safety management systems for wheat and maize, and derived white wheat flour and maize flour, have been evaluated, considering different prevention and practical intervention measures to be applied during storage and processing. For this purpose, through an operational flow chart, authors have performed mycotoxin-hazard analysis in the pre- and post-harvest phases and applied Food Safety Objective (FSO) and Performance Objective (PO) concept. Mycotoxin-hazard and analysis of control measures in the pre-harvest operations indicated that the most important practices at pre-harvest level for the control of mycotoxins in wheat/maize chain may include: (i) land preparation, such as tillage, cover crop and crop rotation, (ii) planting and antifungal mulch treatment, application of botanical extracts and intercropping, (iii) application of fungal biocontrol agents to reduce aflatoxins and (iv) application of fungal and bacterial biocontrol agents. For the post-harvest operations one Critical Control Point (CCP) and five Control Points (CPs) have been determined. The CCP includes an intervention measure that can be applied during storage, such as the application of treatments with volatile bioactive compounds, cold plasma, ozonisation or UV treatment. The results of FSO/PO analysis applied to wheat/maize chain revealed that FSO (the maximum level of mycotoxins in final food products given in European legislation) could be reached by combining conventional production steps such as cleaning and milling with different intervention strategies. For all strategies presented here, application on actual food production site must take into account local specificities and its interaction with climatic conditions. • Mycotoxin-hazard analysis for pre- and post-harvest operations for wheat and maize. • Intervention measure during grain storage as potential critical control point. • Combination of cleaning and milling with intervention measures to reach food safety objectives.

Stabilization of the Dynamic Layer of Composite Membranes by UV Radiation

To stabilize the dynamic layer of cellulose acetate (CA) and polystyrene (PS) membranes, the membrane was exposed to UV radiation using a laboratory setup in atmospheric air. As a base for dynamic membranes, a micro-filtration membrane made of nylon-66 and a membrane made of polytetrafluoroethylene (PTFE) grade MFFC-3G were used. Dynamic membranes PTFE-CA, PTFE-PSd nylon-CA, nylon-PS were obtained by forming a semi-permeable layer on the surface of a porous base from suspended microparticles of PS or CA present in a filtered aqueous solution of acetone with sizes of 81–504 nm and 42–130 nm, respectively, in a dynamic equilibrium with the solution. After obtaining the membranes, the surface was treated for 10 minutes with UV radiation in the wavelength range of 280–320 nm, with a UV radiation power of 36 W. Stabilization of dynamic membranes by UV radiation made it possible to increase the specific productivity of CA membranes 10 times and of PS by 1.5 times, while reducing the retention capacity of those membranes in terms of oil products by 9–17%. UV treatment of polymeric membranes can be used to increase the specific productivity and stabilization of dynamic membranes with a PS surface layer.

Food Waste Management Employing UV-Induced Black Soldier Flies: Metabolomic Analysis of Bioactive Components, Antioxidant Properties, and Antibacterial Potential.

Food waste, as a major part of municipal solid waste, has been increasingly generated worldwide. Efficient and feasible utilization of this waste material for biomanufacturing is crucial to improving economic and environmental sustainability. In the present study, black soldier flies (BSF) larvae were used as carriers to treat and upcycle food waste. Larvae of the BSF were incubated with UV light for 10, 20, and 30 min at a wavelength of 257.3 nm and an intensity of 8 W. The food waste utilization efficiency, antioxidant assays, antibacterial activity, and bioactive metabolites without and with UV treatment were determined and compared. Results showed that the BSF larvae feed utilization rate was around 75.6%, 77.7%, and 71.2% after UV treatment for 10, 20, and 30 min respectively, contrasting with the non-UV induced group (73.7%). In addition, it was perceived that the UV exposure enhanced antioxidant and antimicrobial properties of BSF extracts, and the maximum values were observed after 20 min UV induction time. Moreover, UV-induced BSF extracts showed an improved metabolic profile than the control group, with a change in the amino acids, peptides, organic acids, lipids, organic oxides, and other derivatives. This change in metabolomics profile boosted environmental signaling, degradation of starch, amino acids, sugars, and peptide metabolism. It was concluded that the bioconversion of food wastes using UV-induced BSF larvae can enhance the generation of a variety of functional proteins and bioactive compounds with potent antioxidant and antimicrobial activity. However, more studies are required to exploit the efficiency of UV treatment in improving BSF’s potential for upcycling of food wastes.

Residual solvent-assisted facile deposition of honeycomb-like silver nanoflakes on the surface of electrospun PAN nanofibers

Nobel metal nanoparticles-decorated electrospun nanofibers (ENFs) have attracted great attention for different applications. In the present work, solvent-assisted mild UV treatment was introduced as a unique, efficient and versatile technique for the fabrication of honeycomb-like Ag nanoflakes-decorated electrospun PAN nanofibers. Freshly prepared electrospun PAN nanofibrous membrane from its DMF solution (without vacuum drying) was treated with AgNO3 solution under mild UV irradiation. Microscopic images showed that honeycomb-like Ag-nanoflakes were well decorated on ENFs. XRD showed the formation of amorphous silver materials on the surface of PAN fibers. The Ag nanoflakes-decorated nanofibers showed promising antibacterial properties. Therefore, this facile technique with proposed mechanism can open a new platform for the fabrication of noble metal nanospecies-decorated ENFs for different applications.

Photo-oxygenation of water media using photoactive plasmonic nanocomposites.

Plasmonic nanocomposites ZnO-Ag and ZnO-SnO2-Ag(AgCl) were prepared by the polymer-salt method, and their structure and morphology were studied using XRD and SEM analyses. It was found that the addition of photoactive inorganic nanocomposites ZnO-Ag and ZnO-SnO2-Ag(AgCl) in pure water significantly enhances the effectiveness of its disinfection and purification during UV treatment and provides the effective water oxygenation. Oxygen photogeneration under blue light (λex. = 405nm) can be related to the plasmon-excitation processes in ZnO-SnO2-Ag(AgCl) composites. Prepared composites demonstrate antibacterial activity against both Gram-positive and Gram-negative bacteria. The increase of Ag content in ZnO-Ag and ZnO-SnO2-Ag(AgCl) composites significantly enhances their antibacterial activity.

SnO2/UV/H2O2 and TiO2/UV/H2O2 Efficiency for the Degradation of Reactive Yellow 160A: By-Product Distribution, Cytotoxicity and Mutagenicity Evaluation

Advanced oxidation processes (AOPs) have emerged as a promising approach for the removal of organic dyes from effluents. Different AOPs were employed for the degradation of Reactive Yellow 160A (RY-160A) dye, i.e., SnO2/UV/H2O2 and TiO2/UV/H2O2. In the case of UV treatment, maximum degradation of 28% was observed, while UV/H2O2 furnished 77.78% degradation, and UV/H2O2/TiO2 degraded the RY-160A dye up to 90.40% (RY-160A 30 mg/L, 0.8 mL of H2O2). The dye degradation was 82.66% in the case of UV/H2O2/SnO2 at pH 3. FTIR and LC-MS analyses were performed in order to monitor the degradation by-products. The cytotoxicity and mutagenicity of RY-160A dye were evaluated by hemolytic and Ames (TA98 and TA100 strains) assays. It was observed that the RY-160A dye solution was toxic before treatment, and toxicity was reduced significantly after treatment. Results indicated that UV/H2O2/TiO2 is more efficient at degrading RY-160A versus other AOPs, which have potential application for the remediation of dyes in textile effluents.

UV/O3 assisted ceramic membrane reactor for efficient fouling control and DOM transformations in real textile wastewater

A ceramic membrane reactor (CMR) coupled with an up-flow anaerobic sludge blanket (UASB) reactor has been investigated to treat real textile wastewater, focusing on the synergetic effects of UV and O3 on fouling control and dissolved organic matter (DOM) transformation. The ozone treatment showed high potential in color removal but resulted in a linear (R2 = 0.996) increase in the membrane fouling rate with the increasing ozone dose; the continuous UV (254 nm) exposure significantly retarded membrane fouling by 16 folds but increased soluble chemical oxygen demand. In contrast, when intermittent (15 min ON: 15 min OFF) UV exposure and ozonation (UV/O3) were applied simultaneously, 94% color removal was reached and a synergistic effect on membrane fouling control was prominent, which increased the fouling time by 2.92 and 10.1 folds as compared to the standalone application of UV or ozone, respectively. Confocal laser scanning microscopy observation revealed proteins and polysaccharides as prominent foulants during O3 and UV treatment, respectively. UV–Vis spectroscopy and 3-D excitation-emission matrix fluorescence spectra confirmed the synergistic effects of UV/O3 in the degradation of UV280 and UV254 absorbance and fluorescent DOM. The HO• radicals played a primary role in degrading organic pollutants during UV/O3 treatment. These results provide new insights into the fouling mechanism and DOM transformation in ceramic membrane-based wastewater treatment systems, and recommend simultaneously intermittent application of UV/O3 in an external CMR coupled to UASB as a promising technology for the treatment of textile or other industrial wastewater.

Abstract PR004: In vivo tracking of clonal dynamics during UV-induced skin carcinogenesis

Abstract Background: The impact of chronic UV exposure on clonal dynamics and genomic diversity remains unclear. Our central hypothesis is that skin cancer is induced not by solely accumulation of somatic mutations, but rather a combination of mutations and disruption of the spatial and temporal constraints imposed by the skin’s 3-D architecture. Here we characterize clonal dynamics and transcriptional signatures during skin carcinogenesis using multicolor lineage tracing. Methods: We generated a K14Cre-ERT2 Confetti mice with inducible fluorophore (flr) expression. Mice were UV-irradiated for 3 months. Clones were 3-D digitized using confocal microscopy (z-stacks) and clone volumes estimated computationally. scRNAseq was used to compare UV-exposed (EXP) vs. non-exposed (NON) epidermis vs. skin tumors. Results: We generated 914 serial images of the EXP/NON skin over the course of 6 months following initiation of UV. We analyzed 16,135 clones from the EXP and 21,506 clones from the NON skin. We classified clone sizes into 3 classes represented by the small (<50,000 μm3), medium (50,000-500,000 μm3), and large “goliath” (> 500,000 μm3). The median size of clones does not differ between UV treatments and does not change with time. However, clones from EXP samples have significantly greater mean size than NON ones. Their mean sizes differed by some 1.5-fold, with an over 6-fold increase in variance, resulting in the sizes distribution to be highly skewed towards large clones with a long, narrow tail. Goliath clones are rarely present in the NON skin; however, they increase in number dramatically by months 3-4, plateauing between months 5-6. Using 3 ecological metrics (clone size, clone numbers, and coefficient of variation) we see phase shifts, which primarily distinguish months 1 & 2 from months 3 & 4. scRNAseq of EXP/NON epidermis and tumors revealed differential representation of 16 clusters, the majority of which could be mapped to previously defined keratinocyte populations. We observe dynamic changes to these clusters when progressing from normal skin to chronically exposed skin, and then to tumors. EXP clusters were associated with expression of cystatins (Scfa 3, BC100530), and alarmins/proliferative keratins (Krt16, Krt6a), which have been associated with skin injury. Clusters expressing cystatins and alarmins also increased in tumors. Flr-expressing keratinocytes harvested from large clones in EXP epidermis exhibited altered keratinocyte differentiation (downregulation of Krt77, Loricrin and Nfkbia, upregulation of cystatin), inflammation (downregulation of Nfkbia), and upregulation of metabolic regulators (carbonic anhydrase II and retinol transport (Rbp1)). Genes differentially expressed in exposed skin and retained in tumors may be required for carcinogenesis, while those expressed only in exposed skin likely required for adaptive responses to UV. Our findings have important implications for understanding cancer through an eco-evolutionary framework and designing novel approaches to cancer prevention. Citation Format: Stanislav Avdieiev, Leticia Tordesillas, Omar Chavez Chiang, Zhihua Chen, Luiza Silva Simoes, Y. Ann Chen, Noemi Andor, Robert Gatenby, Elsa R. Flores, Joel S. Brown, Kenneth Y. Tsai. In vivo tracking of clonal dynamics during UV-induced skin carcinogenesis [abstract]. In: Proceedings of the AACR Special Conference on the Evolutionary Dynamics in Carcinogenesis and Response to Therapy; 2022 Mar 14-17. Philadelphia (PA): AACR; Cancer Res 2022;82(10 Suppl):Abstract nr PR004.

A Simple Alcohol-based Method of Oocyst Inactivation for Use in the Development of Detection Assays for Cryptosporidium

Cryptosporidium spp. are obligate, intracellular parasites that cause life-threatening diarrhea among children and immunocompromised adults. Transmission occurs by the fecal-oral route following ingestion of thick-walled oocysts that can contaminate, persist, and resist disinfection in water and food. Sodium hypochlorite, peroxides, ozone, formaldehyde, and ammonia are suitable disinfectants against Cryptosporidium oocysts. Effective concentrations of these chemicals can be toxic and not practical for downstream research use of non-viable oocysts. Oocyst inactivation approaches such as UV light, heat, and treatments with ethanol or methanol are generally more accessible for routine lab use, yet their applicability in Cryptosporidium assay development is limited. The aims of this study were to evaluate methods of inactivation of Cryptosporidium oocysts that can be readily applied in the laboratory and test the utility of whole inactive oocysts in quantitative PCR (qPCR). Experiments were performed on C. parvum oocysts subjected to heat (75 °C/10 min) or treated with increasing concentrations of ethanol and methanol over time. Viability assays based on propidium iodide (PI) staining, in vitro excystation, and infection of the Hct-8 cell line were used to evaluate the efficacies of the treatments. Excystation of sporozoites was not impaired with 24 h exposures of oocysts to 50% ethanol or methanol, even though significant PI incorporation was observed. Concentrations of ≥70% of these chemicals were required to completely inhibit excystation and infection of Hct-8 cells in vitro. Inactivated oocysts stored for up to 30 days at 4 °C retained cyst wall integrity and antigenicity as observed by light microscopy and immunofluorescence. Moreover, non-viable oocysts applied directly in qPCR assays of the COWP gene were useful reference reagents for the identification and quantification of Cryptosporidium in spiked water samples. In summary, we have established a practical approach to inactivate C. parvum oocysts in the laboratory that is suitable for the development of detection or diagnostic assays targeting the parasite.

Fabrication of TiO2 ̶ KH550 ̶ PEG Super-Hydrophilic Coating on Glass Surface without UV/Plasma Treatment for Self-Cleaning and Anti-Fogging Applications

In this study, we have developed a self-cleaning transparent coating on a glass substrate by dip coating a TiO2 – KH550 – PEG mixed solution with super-hydrophilicity and good antifogging properties. The fabrication of the thin-film-coated glass is a one-step solution blending method that is performed by depositing only one layer of modified TiO2 nanoparticles at room temperature. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to determine the structure and morphology of the nanoparticles and the thin-film-coated glass. The surface functional groups were investigated using Fourier-transform infrared spectroscopy (FT-IR), and the optical properties of the glass coating were measured using a UV/Vis spectrometer. The results revealed that the KH-500-modified TiO2 film coating was in an anatase crystalline form. The hydrophilicity of the coated and uncoated glass substrates was observed by measuring their water contact angle (WCA) using a contact angle instrument. The maximum transparency of the coated glass measured in the visible region (380–780 nm) was approximately 70%, and it possessed excellent super-hydrophilic properties (WCA ~0°) at an annealing temperature of 350 °C without further need of UV or plasma treatment. These results demonstrate the super-hydrophilic coated glass surface has potential for use in self-cleaning and anti-fogging applications.

Inactivation of Salmonella and Escherichia coli in Surface Agricultural Water Using a Commercial UV Processing Unit

Treatment of agricultural water aids in the prevention of foodborne disease outbreaks linked to contaminated fresh produce. UV light is a suitable alternative for treating drinking water but is not always effective for surface irrigation water due to interference caused by turbidity and high microbial loads. The effectiveness of UV treatment for reducing Escherichia coli and Salmonella in surface water used in agriculture was evaluated. Six pond water samples were collected on each of 16 sampling dates over a 3-year period. On each corresponding testing date, three samples were inoculated with Salmonella enterica serovars Hartford, Montevideo, and Gaminara and the other three samples were inoculated with E. coli ATCC 25922, targeting a concentration of 7 log CFU/mL. Inoculated water was UV treated with a commercially available juice processing UV device at a constant UV dose of 14.2 mJ/cm2 and a turbulent flow regime. The effects of date, initial bacterial counts, and water pH and turbidity on log reductions of both microorganisms were determined. Initial bacterial counts and test date significantly predicted microbial reduction (multivariate P < 0.001), but neither pH nor turbidity influenced microbial reductions (P > 0.05). UV treatment reduced both Salmonella and E. coli by a mean of >6 log CFU/mL.

Multi-dimensional "projection" - the impact of abiotic stresses on the content of seven active compounds and expression of related genes in Glycyrrhiza uralensis Fisch

Triterpenoids and flavonoids from licorice ( Glycyrrhiza uralensis Fisch.) are known to have a wide range of applications in the pharmaceutical, skin care, and food industries. The effects of various types of abiotic stresses and associated phytohormones - polyethylene glycol, sodium chloride, ultraviolet, cadmium, abscisic acid, and methyl jasmonate - on both the content of these secondary metabolites and the transcript levels of genes encoding enzymes of important biosynthetic pathways were evaluated in hydroponic seedlings of G. uralensis . In these treatments, abscisic acid induced a substantial increase in the levels of the four active compounds, compared to the control. Analysis of the expression of genes involved in the biosynthetic pathways of these compounds, such as FPPS , showed that their transcript levels were significantly up-regulated in the four stresses. These findings suggested that the multi-stress superposition pattern of the content of active compounds and the gene expression of their biosynthetic pathways may provide insights to explore the management of secondary metabolite synthesis pathways in medicinal plants. It could facilitate a better understanding of the formation patterns of active compounds in licorice in artificial cultivation. Further insights may also be provided to increase the yield of these high value components. • Exogenous abscisic acid has a positive effect on the active compounds of licorice. • Glycyrrhizic acid-related gene expression was uprated in PEG and UV treatments. • Hydroponic system can be used to study the effect of abiotic stresses on licorice. • Multi-stress has potential in regulation and production of secondary metabolites.

Preparation, stability, antioxidative property and in vitro release of cannabidiol (CBD) in zein-whey protein composite nanoparticles

Cannabidiol (CBD) containing products are getting more and more popular in the global markets. But wide applications of CBD are still hindered by its inherent sensitivity to environmental stresses, its poor water solubility and low bioavailability. CBD was entrapped in zein and whey protein (WP) hybrid nanoparticles using a drop-by-drop anti-solvent precipitation method. Characteristics of the nanoparticles including particle size, polymer dispersity index, zeta-potential as well as encapsulation efficiency were influenced by zein to WP ratio. WP coating improved the encapsulation efficiency of CBD molecule and re-dispersibility of the lyophilized nanoparticles. Differential Scanning Calorimetry (DSC) showed that CBD molecule's transform from crystallized to amorphous state. Fourier Transform Infrared Spectrometry (FT-IR) indicated the main driving forces of hydrogen bond and hydrophobic forces involved in complexing of zein and WP. Compared with zein nanoparticles, zein-WP nanoparticles were more effective in protecting CBD against UV and thermal treatment and during storage at 4 °C for 21 days. The antioxidant activity and in vitro release of CBD were improved by encapsulating in zein-WP nanoparticles. Data indicated that zein nanoparticles stabilized by WP may be a useful colloidal system to protect CBD and the similar compounds during food processing.

Micropollutant removal and disinfection byproduct control by sequential peroxymonosulfate-UV treatment in water: A case study with sulfamethoxazole

UV/peroxymonosulfate (UV/PMS) advanced oxidation process has attracted significant attention for removal of micropollutants in water. However, during practical water treatment applications, the PMS treatment must be performed before the UV treatment to achieve full contact. In this study, sulfamethoxazole (SMX) was selected as the target micropollutant. Four different operational approaches, including UV alone, PMS alone, simultaneous UV/PMS and sequential PMS-UV, were compared for their differences in SMX removal and disinfection by-product (DBP) formation potentials during chlorine-driven disinfection. Among the four approaches, UV/PMS and PMS-UV achieved over 90% removal efficiencies for SMX without substantial differences. For raw water, the trichloronitromethane (TCNM) formation potential after treatment with PMS-UV was lower than that after UV/PMS treatment. The time interval over which the PMS-UV process was conducted had little effect on the final removal efficiency for SMX. However, a brief (5 min) pre-PMS treatment significantly reduced the TCNM formation potential and the genotoxicity from DBPs. The formation risk for TCNM during chlorination increased markedly with increasing PMS dosages, and the appropriate dosage under these experimental conditions was suggested to be 0.5–1.0 mmol/L. Under alkaline conditions, PMS-UV treatment can enhance SMX degradation as well as dramatically reduced the formation potentials for haloketones, haloacetonitriles and halonitromethanes. This study suggests that proper optimization of UV/PMS processes can remove SMX and reduce its DBP formation.

Surface characterization of polyimide and polyethylene terephthalate membranes toward plasma and UV treatments

This study is to bring an overview on various methods regarding the surface treatment performed on different polymeric membranes in relation to a deference between the treatment mechanism and their chemical structure. Herein, plasma and UV surface treatments (PST and UST) were utilized to treat the surfaces of two commercial membranes, i.e., aromatic polyimide and polyethylene terephthalate for various durations using a discharge electrode and an UV LED curing system, respectively. Based on the effects of PST and UST processes on the surface of these membranes, their surface properties have been characterized to surface morphology and hydrophilicity (or wettability), at same time the changes have probably occurred on their surface during the PST and UST processes. As a result, their hydrophilic behavior was significantly enhanced after conducting these treatment processes based on the investigation of water contact angle. Moreover, Fourier-transform infrared and Raman spectroscopy manifested the changes in the chemical bonds, interactions and orientations of molecules, which confirmed the apparition and insertion of polar functional groups after the surface treatments, and accordingly, their wettability was enhanced significantly. Also, optical microscopy images showed direct impactions on their surface and the evidence of slight surface aging/damage during the treatment processes based on the presentation of the strange streaks on the treated surfaces. In particular, the peel forces exhibited an increase comparing to the initial membranes, which is characteristically for enhancing their adhesion behavior. Hence, these results are needful for improving the surface properties of a material, and obtaining better adhesion behavior on the membrane-like materials and recycling polymer materials.