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Abstract: Background: UV-exposures result in accumulation of genetic lesions that facilitate the development of skin cancer. Numerous pharmacologic agents are currently under development to both inhibit formation of DNA lesions and enhance repair. Drugs must be evaluated in vitro, currently performed in cell culture systems, before being tested on humans. Current systems do not account for the architecture and diverse cellularity of intact human skin. Objective: To establish a novel, functionally viable, and reproducible in vitro skin organ culture system for studying the effects of various pharmacologic agents on DNA repair. Methods: Human skin was obtained from neonatal foreskins. Intact skin punches derived from foreskins were cultured in vitro prior to exposure to UV-irradiation, and evaluated for DNA-damage using a DNA dot blot. Serial skin biopsies were obtained from patients with actinic keratoses treated with topical imiquimod. Expression of immune-stimulating and DNA repair genes was evaluated in ex vivo and in vitro samples. Results: DNA dot blots revealed active repair of UV induced lesions in our in vitro skin organ culture. The photo-protective effect of sunscreen was detected, while imiquimod treatment did not enhance DNA repair in vitro. The DNA repair molecules XPA and XPF were up-regulated in the skin of imiquimod treated patients with actinic keratoses and imiquimod treated bone marrow-derived cell lines, but not keratinocytes. Conclusion: Our in vitro human skin organ culture model detected repair of UV-induced DNA lesions, and may be easily adapted to investigate various photo-protective drugs intended to prevent or treat skin cancer. [Copyright &y& Elsevier]

The present investigation was conducted with the objective to study the effects of various treatments and storage conditions on ascorbic acid, total phenols, antioxidant activity and polyphenol oxidase activity of mung bean sprouts. The sprouts subjected to various treatments viz., pulsed electric field (PEF) (10,000 V for 10 s), hot water dip (HWD) (50 °C for 2 min), ethanol vapours (1 h) and UV-Irradiation (10 kJm in laminar flow chamber for 1 h); and then stored at room (25 ± 1 °C) and low (7 ± 1 °C) temperature conditions. The sprouts were analyzed regularly at 24 h interval till end of shelf life. Different treatments given to sprouts resulted in differential effect on various parameters. The ascorbic acid, total phenols and antioxidant activity were highest in ethanol vapours treated sprouts. There was a general decrease in polyphenol oxidase activity by various treatments. During storage ascorbic acid, total phenols and antioxidant activity of sprouts first increased and then decreased significantly, however, for polyphenol oxidase activity a progressive increase with increase in storage period was observed. The trends were similar at room and low temperature storage conditions. Thus, it can be concluded that the ethanol vapours significantly improved the ascorbic acid content, total phenols and antioxidant activity of mung bean sprouts, both at room as well as low temperature conditions of storage. [ABSTRACT FROM AUTHOR]

Highlights: [•] We developed self-organized polystyrene film by UV exposure and soaking in solvents. [•] The results provide the effects of crosslinking and oxidation for nanostructure. [•] XPS results showed the impact toward the oxidation parts by solvents. [ABSTRACT FROM AUTHOR]

Overexpression and/or abnormal cleavage of amyloid precursor protein (APP) are linked to Alzheimer's disease (AD) development and progression. However, the molecular mechanisms regulating cellular levels of APP or its processing, and the physiological and pathological consequences of altered processing are not well understood. Here, using mouse and human cells, we found that neuronal damage induced by UV irradiation leads to specific APP, APLP1, and APLP2 decline by accelerating their secretase-dependent processing. Pharmacological inhibition of endosomal/lysosomal activity partially protects UV-induced APP processing implying contribution of the endosomal and/or lysosomal compartments in this process. We found that a biological consequence of UV-induced-secretase processing of APP is impairment of APP axonal transport. To probe the functional consequences of impaired APP axonal transport, we isolated and analyzed presumptive APP-containing axonal transport vesicles from mouse cortical synaptosomes using electron microscopy, biochemical, and mass spectrometry analyses. We identified a population of morphologically heterogeneous organelles that contains APP, the secretase machinery, molecular motors, and previously proposed and new residents of APP vesicles. These possible cargoes are enriched in proteins whose dysfunction could contribute to neuronal malfunction and diseases of the nervous system including AD. Together, these results suggest that damage-induced APP processing might impair APP axonal transport, which could result in failure of synaptic maintenance and neuronal dysfunction. [ABSTRACT FROM AUTHOR]

Thin films by solvent evaporation from mixture of collagen, chitosan and silk fibroin were prepared. The surface properties of biopolymeric films were investigated using technique of Atomic Force Microscopy and by means of contact angle measurements allowing the calculation of surface free energy. Measurements of the contact angle on the surface were made and surface free energy was calculated. The surface of films was modified by UV-irradiation (λ = 254 nm and 248 nm). It was found that the surface roughness of biopolymeric films decreased with increasing UV-irradiation time. Polar component of the surface free energy increased with increasing UV-irradiation time. [ABSTRACT FROM PUBLISHER]

Films of polystyrene and styrene ionomers with various content of sodium acrylate were studied in terms of changes in surface properties after UV-irradiation or plasma action. The alterations were examined by contact angle measurements and FTIR-ATR spectroscopy. Both UV-irradiation (3h and 4h) and the plasma action (30s) induced a growth in the sample hydrophilicity owing to appearance of polar groups on the surfaces. More effective alterations of surface polarity were caused by the plasma action. However, these changes were reversible, contrary to the results caused by UV-irradiation. Photons can penetrate deeper into the sample rendering the changes more durable. [ABSTRACT FROM PUBLISHER]

Highlights: [•] A method of panthenol-stabilized ceria nanoparticles synthesis was developed. [•] Panthenol/CeO2 protects cells from ROS/UV better than individual panthenol or CeO2. [•] The degree of protection is determined by panthenol-to-ceria molar ratio. [•] Panthenol/CeO2 contributes to survival of cells both before and after UV irradiation. [Copyright &y& Elsevier]

Antifouling schematic diagram of the composite hydrophilic luminescent coating and schematic diagram of antifouling principle of luminescent layer. [Display omitted] • A novel composite antifouling coating inspired by Watasenia Scintillans is designed by combining hydrophilic surface and luminescence layer. • The highly hydrophilic transparent layer is prepared by pre-embedded active site and UV initiating zwitterion polymerization. • The luminescence layer shows a significant interference on biorhythm of fouling organisms, and achieves anti-fouling effectively cooperated with the hydrophilic coating. Marine bio-fouling has been a longstanding problem facing the marine industry, which affects the underwater facilities and causes serious economic losses. It is highly desirable to develop an effective antifouling coating currently. Here a novel antifouling coating inspired by Watasenia Scintillans is reported, which achieves excellent performance by synergism of highly hydrophilic surface and luminescence layer, where pentaerythritol triacrylate embedded in the acrylic resins provides active sites for the graft of poly (sulfobetaine methacrylate) (PSBMA) brush via UV-initiation. The antifouling test results show that the coating can effectively resist the adhesion of non-specific proteins, i.e. the adsorption amount of bovine serum albumin is decreased from 220.83 ng/cm2 of blank control to 40.01 ng/cm2, and the attachment amount of Phaeodyylum tricornutum is decreased to 67n/mm2, which is nearly one-sixth of the blank control (383n/mm2). After compounding fast rechargeable fluorescent particles with PSBMA coating, the adhesion amount of diatoms is further dropped to 4n/mm2, since long-lasting light can effectively interfere with the normal biorhythm of fouling organisms. The long-term underwater field tests results also proved the long-term durability and excellent performance of the hydrophilic luminescent coating in the complex actual aquatic environment. It is believed that the advantageous characteristics of the as-described composite eco-friendly coating and simplicity of the preparation process will be a pioneer for future marine anti-biofouling industry, since various biological fouling at different period underwater can be inhibited effectively. [ABSTRACT FROM AUTHOR]

Abstract: Thin films by solvent evaporation from mixture of chitosan and silk fibroin were prepared. The interactions between components in the blend were studied by FTIR spectroscopy. The surface properties of chitosan/silk fibroin blended films were investigated using the technique of Atomic Force Microscopy (AFM) and by means of contact angle measurements allowing the calculation of surface free energy. Measurements of the contact angle for diiodomethane (D), and glycerol (G) on the surface of chitosan films and chitosan/silk fibroin films were made and surface free energy was calculated. The surface of thin films based on the blends of chitosan and silk fibroin was modified by UV-irradiation with the wavelength λ=254nm. It was found that chitosan/silk fibroin blend surface is enriched in high surface energy component i.e. silk fibroin. The contact angle and the surface free energy were altered by UV-irradiation for both chitosan and chitosan/silk fibroin films. The surface roughness of chitosan, silk fibroin and chitosan/silk fibroin blended films was altered by UV-irradiation. UV-irradiation caused the decrease of surface roughness of chitosan films, silk fibroin films and films made of the mixture of chitosan and silk fibroin. [Copyright &y& Elsevier]

An atomic force microscope probe can be formed into an ultra-sharp cylindrical shape (a nanoneedle) using micro-fabrication techniques such as focused ion beam etching. This nanoneedle can be effectively inserted through the plasma membrane of a living cell to not only access the cytosol, but also to penetrate through the nuclear membrane. This technique shows great potential as a tool for performing intranuclear measurements and manipulations. Repeated insertions of a nanoneedle into a live cell were previously shown not to affect cell viability. However, the effect of nanoneedle insertion on the nucleus and nuclear components is still unknown. DNA is the most crucial component of the nucleus for proper cell function and may be physically damaged by a nanoneedle. To investigate the integrity of DNA following nanoneedle insertion, the occurrence of DNA double-strand breaks (DSBs) was assessed. The results showed that there was no chromosomal DNA damage due to nanoneedle insertion into the nucleus, as indicated by the expression level of γ-H2AX, a molecular marker of DSBs. [ABSTRACT FROM AUTHOR]

HALS-functional core-shell nanoparticles, poly(BA-MMA-PMPA), were prepared by emulsion polymerization. The chemical structure and the microstructure of the particles was confirmed by Fourier transformed infrared (FTIR) and transmission electron microscopy (TEM), respectively. The nanoparticles were used to modify PBT and had good compatibility with PBT. The mechanical properties before and after UV-irradiation analysis demonstrated that the UV-resistance and impact resistance of PBT were obviously improved by poly(BA-MMA-PMPA). The degradation degree of PBT was retarded by poly(BA-MMA-PMPA) as studied by thermogravimetry analysis (TGA). The surface chemical functional groups changes revealed that the surface of PBT was greatly protected by poly(BA-MMA-PMPA). [ABSTRACT FROM AUTHOR]

Background: The complexity of reactions and kinetic is the current problem of photodegradation processes. Recently, artificial neural networks have been widely used to solve the problems because of their reliable, robust, and salient characteristics in capturing the non-linear relationships between variables in complex systems. In this study, an artificial neural network was applied for modeling p-cresol photodegradation. To optimize the network, the independent variables including irradiation time, pH, photocatalyst amount and concentration of p-cresol were used as the input parameters, while the photodegradation% was selected as output. The photodegradation% was obtained from the performance of the experimental design of the variables under UV irradiation. The network was trained by Quick propagation (QP) and the other three algorithms as a model. To determine the number of hidden layer nodes in the model, the root mean squared error of testing set was minimized. After minimizing the error, the topologies of the algorithms were compared by coefficient of determination and absolute average deviation. Results: The comparison indicated that the Quick propagation algorithm had minimum root mean squared error, 1.3995, absolute average deviation, 3.0478, and maximum coefficient of determination, 0.9752, for the testing data set. The validation test results of the artificial neural network based on QP indicated that the root mean squared error was 4.11, absolute average deviation was 8.071 and the maximum coefficient of determination was 0.97. Conclusion: Artificial neural network based on Quick propagation algorithm with topology 4-10-1 gave the best performance in this study. [ABSTRACT FROM AUTHOR]

In this study, the anaerobic hydrolytic degradation of cefpodoxime proxetil (CP) in the presence of UV-light irradiation and in darkness has been studied at Britton-Robinson (B-R) buffer solutions (pH 2.5-11) by cyclic and square-wave voltammetry techniques. By means of these electrochemical techniques, the hydrolytic degradation of CP was successfully followed. The pH effect on this degradation was also investigated. In darkness, the decrease in the peak current of CP was not practically observed at the acidic and physiological pHs (2.5, 5.0 and 7.4). But, in the basic medium (pH 9.0 and 11.0), a decrease in the peak current was detected. On the other hand, UV irradiation caused a decrease in the peak current of CP and a positive shift in its cathodic peak potential. Under the UV irradiation, the maximum stability of CP was observed in B-R buffer of pH 5. It has been determined that UV irradiation has a great effect on hydrolytic degradation of CP at basic medium. On the other hand, at pHs ⩾ 7.4, a new peak has been also obtained at more positive potential than that of the first reduction peak of CP. The current of this peak increases by increasing UV irradiation time. This peak could be assigned to the reduction of a new electroactive product which was formed from the hydrolytic degradation of CP under UV irradiation. The hydrolytic degradation reaction of CP followed pseudo-first order kinetics [ABSTRACT FROM AUTHOR]

UV-induced DNA damage plays a key role in the etiology of certain diseases. The ability of blueberry anthocyanins and anthocyanidins (BA) to protect cellular DNA from UV-induced damage was investigated. BA were extracted by water (BAW), ethanol (BAE) or methanol (BAM). These extracts partially restored proliferation of UV-irradiated HepG2 cells as shown by MTT assay. Treatment with BA extracts at 75 μg/ml decreased reactive oxygen species and decreased DNA damage by tail moment of comet assay and expression of γH2AX in situ. BAM significantly decreased gene and protein expression of p53, phospho-p53 (Ser15), and p21 in UV-irradiated HepG2 cells. BA thus efficiently protects cells from DNA damage in vitro. Blueberry may potentially be used as a good source of naturally radioprotective agents. [ABSTRACT FROM AUTHOR]

The blends based on poly(lactic acid), (PLA) and polyacrylates (1:1 weight ratio) have been prepared by photopolymerization of three different multifunctional acrylate monomers (pentaerythritol triacrylate, pentaerythritol tetraacrylate and dipentaerythritol pentaacrylate) in matrix of linear PLA. The structure of these systems has been studied by Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC) and X-ray Diffraction (XRD). It was found that the blends are highly crosslinked, rough, heterogeneous and some of them - semicrystalline. The effect of UV-irradiation on surface morphology of obtained mixtures was studied. The viscometry has been applied for measurements of changes of PLA molecular weight resulting of photodegradation. It was shown that blends are much more photostable than pure PLA. [ABSTRACT FROM AUTHOR]

Cereal grains are a favorable habitat for aflatoxin- producing fungus to develop. the current investigation was carried out to evaluate the quantity and kind of contaminated imported grains and rice generated in the province of Shiraz, Iran. A total of 60 random rice samples were taken from paddy fields in October and November 2020. Aspergillus genera were detected using PCR. HPLC was used to determine the quantity and type of aflatoxin and mycotoxins in samples collected. Irradiation studies were carried out utilizing a collimated beam system with wavelengths ranging from 200 to 360 nm. The quality of rice was assessed using UV light therapy on some of the changed factors, such as amylose content, aroma, and brightness [ P  <  0.05 ]. Aspergillus genera were found in 33.3% [20 samples of 60] of rice samples after morphological and molecular analysis of the ITS gene. According to the sequencing experiment, 12 strains [60%] were identified as Aspergillus flavus , whereas 8 strains [40%] were identified as Aspergillus parasiticus . Ver-1 and afl-R genes were positive in 12/12 [100%] Aspergillus flavus and 87.5% in Aspergillus parasiticus. According to the HPLC findings, three Aspergillus parasiticus strains [37.5%] were able to create all four types of aflatoxins, and aflatoxins B1, B2, G1, G2 were produced by 16.6% of Aspergillus flavus strains. Aflatoxin-1 (AFG1) was lowered to 35.1, 48.2, 59.9, and 65.2%, significantly, at doses of 1.22, 2.44, 3.66, and 4.88 Jcm -2 [ P  <  0.01 ]. Furthermore, at doses of 1.22, 2.44, 3.66, and 4.88 Jcm -2 , AFB2 and AFG2 was shown to be reduced by 13.1%, 11.7%, 30.3%, and 28.9%. [ P  <  0.05 ]. At a maximum dose of 4.88 Jcm -2 , AFB1 was shown to be extremely susceptible to UV irradiation, with a > 70% decrease seen [ P  <  0.001 ]. Our findings imply that UV irradiation with lower energy and lower danger can help minimize aflatoxin contamination in food., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)

This study aimed to determine whether a broad-spectrum liposomal sunscreen with a very high sun protection factor ( Daylong actinica) can prevent damage induced by ultraviolet ( UV) irradiation in patients with cutaneous lupus erythematosus ( CLE) and healthy controls ( HCs) under standardised conditions. In 20 patients with CLE and 10 HCs, defined areas of sunscreen-untreated and sunscreen-treated skin on the upper back were irradiated with combined UVA/ UVB light. Disease-specific skin lesions were induced by UVA/ UVB light in the untreated areas of nine patients with CLE; no specific eruptions or any sun damage was observed in the sunscreen-treated areas in any of the CLE patients, nor in the HCs. Histological analysis of skin biopsy specimens confirmed the clinical results. In conclusion, the use of a high-protection, broad-spectrum sunscreen can prevent UV-induced damage in patients with CLE and HCs. [ABSTRACT FROM AUTHOR]

In this study, in order to develop a new photosensitive gel film, NbO gel films including a chelate ring were prepared by the sol-gel method. Photosensitive and patterning properties of the gel films were investigated. Properties such as refractive index for annealed films were also evaluated. In the electronic absorption spectra of the gel films, the absorption peak assigned a chelate ring was observed at 353 nm, this peak intensity decreased by UV irradiation. From this result, the obtained gel films exhibit photosensitivity. Fine patterns (minimal width of about 2 μm) could be fabricated. It was found that the value of refractive index reaches a maximum of 2.25 for the film heat-treated at 800 °C. [ABSTRACT FROM AUTHOR]

Abstract: Influence of dissolved organic matter (DOM) on particle-water interactions of trace metals (Co, Cu, and Cd) between particulate (>0.2 μm) and dissolved (≤0.2 μm) phases has been investigated along a salinity gradient using samples from the estuarine area of northern Sagami Bay, Japan. Partitioning experiments were performed by mixing riverine suspended particles with the mixtures of different proportions of river and marine end-members and determining concentrations of Co, Cu and Cd in particulate and dissolved phases. Concentrations and distribution coefficients (K d s) between particulate and dissolved phases of Co and Cu were dependent on the presence of DOM. The K d s of Co and Cu in the mixtures in the presence of DOM were lower than those in mixtures that had been ultraviolet-irradiated (UV-irradiated) (absence of DOM), throughout the salinity gradient. In addition, speciation calculations estimated that a greater fraction of Co and Cu in the dissolved phase was present in organic form throughout the salinity gradient, while the seawater ion concentrations and ligand competition (e.g., competition from Ca and Mg and formation of stable and soluble chloro-, sulphato-, and carbonato complexes) had a small effect on the speciation of Co. These results indicate that DOM may play an important role in controlling the speciation and the particle-water interactions of Co and Cu in the estuarine waters. As for Cd, the effect of DOM on the interactions of this metal was less intense than for Co and Cu. Seawater ions appeared to act as an important variable for controlling the particle-water interactions of Cd in the estuarine waters. [Copyright &y& Elsevier]

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Abstract: Objective: To examined the immediate and 24 hours post- irradiation germicidal effects of UV-C lamp on eggs and adults of house dust mites Dermatophagoides pteronyssinus (D. pteronyssinus) and Dermatophagoides farinae (D. farinae). Methods: This study investigated the immediate and 24 hours post irradiation mortalities of adult mites exposed to UV-C at different exposure times (5 mins, 10 mins, 15 mins, 20 mins, 30 mins and 60 mins) and distances (10 cm, 25 cm, 35 cm, 45 cm and 55 cm). Fresh eggs of the 2 dust mites were also irradiated at 10, 35 and 55 cm for 0.5, 1, 2, 3, and 5 minutes, and observed daily post- irradiation for up to 7 days. Results: Highest immediate mortality of 100% occurred with direct irradiation at 10 cm distance from UV-C lamp and for 60 mins, for both species of mites. The post 24 hours mean mortality rates were (58.4±17.4)% for D. pteronyssinus and (27.7±9.7)% for D. farinae when irradiated for 1 hour at 55 cm distance under UV-C lamp. When mites were irradiated in the presence of culture media, the highest mortality rates were lower compared to the direct irradiation; at 10 cm distance and 60 mins exposure, the mean mortality was (74.0±6.8)% for D. pteronyssinus and (70.3±6.7)% for D. farinae. Egg hatchability for both species of mites was also notably reduced by greater than 50% following irradiation. Conclusions: Ultraviolet C irradiation is lethal to an array of organisms by damaging their nucleic acids (DNA and RNA). This study demonstrates the increasing mite mortalities with increasing exposure times and decreasing distances. [Copyright &y& Elsevier]

Neat poly( l-lactic acid) (PLLA) and poly( d-lactic acid) (PDLA) films and PLLA/PDLA blend films were prepared by solution casting, and their photodegradation by UV-irradiation was investigated using wide-angle X-ray scattering (WAXS), gel permeation chromatography, differential scanning calorimetry, tensile testing, and polarized optical microscopy. The PLLA/PDLA blend film was more photodegradation-resistant than the neat PLLA and PDLA films when photodegradation was monitored by molecular weight, melting temperature, and WAXS crystalline peak positions. This indicates that the chains in both amorphous and crystalline regions of the PLLA/PDLA blend film were photo-cleavage-resistant compared to those of the neat PLLA and PDLA films. The changes in melting temperature and WAXS crystalline peak positions before and after photodegradation respectively indicated the increased crystalline lattice disorder and the decreased crystalline lattice sizes of the neat PLLA and PDLA films, whereas these changes were insignificant for the blend films. Photodegradation caused no significant change in tensile properties, with the exception of significant decreases in the tensile strength and elongation at break of PLLA/PDLA blend film. However, the tensile strength and elongation at break of the PLLA/PDLA blend film retained higher values compared to those of the neat PLLA and PDLA films during photodegradation. In spite of the slower photodegradation of the PLLA/PDLA blend film traced by M, T, and WAXS crystalline peak positions than that of neat PLLA and PDLA films, the rapid decrease in tensile strength and elongation at break of the former than that of the latter should be due to the highly-ordered structural difference between them, i.e., the three dimensional dry gel of the former and the spherulites of the latter. [ABSTRACT FROM AUTHOR]

Abstract: The present study involves the development of stabilized and densely dispersed chitosan-silver nanoparticles using a green approach based on electrochemical oxidation/complexation process followed by UV irradiation reduction. Formation of the nanoparticles was confirmed by appearance of surface plasmon absorption around 420nm. The nanoparticles were characterized using transmission electron microscopy, X-ray diffraction, elemental analysis, atomic absorption, energy dispersive X-ray, Fourier transform infrared, and UV–Visible spectrophotometry. The obtained nanoparticles were uniform and spherical with average size of 2–16nm. It was found that increasing the Ag content in the chitosan-Ag based films tends to decrease their equilibrium swelling values. The nanoparticles also demonstrated a relatively high antibacterial activity against Bacillus thuringiensis and Pseudomonas aeruginosa bacteria as compared to that of chitosan and the antibacterial activity increased with increasing the nanoparticle concentration. The obtained results revealed that the prepared nanoparticles could be tailored and used in various biomedical applications. [Copyright &y& Elsevier]

The present study highlighted the aromatic-participant interactions in in vivo trimerization of HSF1 and got an insight into the process of HSF1 protecting against apoptosis. In mouse embryonic fibroblasts (MEFs), mutations of mouse HSF1 (W37A, Y60A and F104A) resulted in a loss of trimerization activity, impaired binding of the heat shock element (HSE) and lack of heat shock protein 70 (HSP70) expression after a heat shock. Under UV irradiation, wild-type mouse HSF1 protected the MEFs from UV-induced apoptosis, but none of the mutants offered protection. We found that normal expression of HSF1 was essential to the cell arrest in G2 phase, assisting with the cell cycle checkpoint. The cells that lack normal HSF1 failed to arrest in the G2 phase, resulting in the process of cell apoptosis. We conclude that the treatment with UV or heat shock stresses appears to induce the approach of HSF1 monomers directly via aromatic-participant interactions, followed by the formation of a HSF1 trimer. HSF1 protects the MEFs from the stresses through the expression of HSPs and a G2 cell cycle arrest. [ABSTRACT FROM AUTHOR]

The development of biodegradable packaging materials, especially from renewable resources is a constant preoccupation of nowadays, because of the environmental problems caused by synthetic polymers. The combination of cellulose with other polymeric materials could be an ecologic alternative and a way to use renewable resources for food packaging. Bacterial cellulose which is produced by microbial fermentation is also a promising material which can be used not only in biomedical application, but also as food packaging material. In this research different composite films between poly(vinyl alcohol)-bacterial cellulose (PVA-BC) were obtained by casting method. The obtained films were UV irradiated for different periods of times from 1 to 10 hours, using a mercury lamp, Philips TUV-30, emitting light mainly at 254 nm. Changes in FT-IR spectra before and after UV irradiation and the modification of transparency and of the swelling characteristics of the films were observed. As it was expected the composites materials are sensitive at UV exposure. [ABSTRACT FROM AUTHOR]

Lycopene antioxidant activity in the presence of two different mixtures of phospholipids in hexane solution, under continuous regime of UV-irradiation from three different ranges (UV-A, UV-B, and UV-C) has been evaluated in this work. Lycopene expected role was to control lipid peroxidation, by scavenging free radicals generated by UV-irradiation, in the presence and in the absence of selected photosensitizer, benzophenone. This work shows that lycopene undergoes to UV-induced destruction (bleaching), highly dependent on the incident photons energy input, more expressed in the presence than in the absence of benzophenone. The further increase ('excess') of its bleaching is undoubtedly related to the further increase of its antioxidant activity in the presence of benzophenone, having the same cause: increase of (phospholipids peroxidation) chain-breaking activities. [ABSTRACT FROM AUTHOR]

Abstract: Marine fish larvae are sensitive to infections by opportunistic bacteria. Procedures like disinfection and pulse feeding may destabilise the microbial community and promote r-selection and proliferation of opportunists in intensive rearing tanks. Recirculation aquaculture systems (RAS) have been hypothesised to stabilise and mature the microbial community, creating a more beneficial environment for the larvae during the live feed period. Two marine RAS with Atlantic cod larvae (Gadus morhua L.) with either moderate ozonation (RAS O3) or high intensity UV-irradiation (RAS UV) were compared with a flow-through system (FTS). The two RAS developed a different and more stable composition of the microbial community than the FTS. The RAS O3 had a more mature and stable microbial community than the RAS UV. The density and the activity of bacteria were higher in the rearing tanks than in the in-flowing water in the RAS UV system, whereas for the RAS O3 system densities and activity of bacteria were similar, indicating low disinfection efficiency with moderate ozonation. Atlantic cod larvae reared in the RAS O3 showed the best survival and growth, whereas the RAS UV larvae performed equally well or better than their siblings in the FTS. This was in spite of the fact that the physicochemical water quality of the two RAS was inferior to that of the FTS. The agar-based method used to quantify opportunists may be too general to capture important differences in the microbial community of the rearing water. For the future, molecular methods could be used to identify which functional groups or species of bacteria are contributing to the observed RAS effect. Our results support the hypothesis of RAS as a microbial control strategy during first feeding of larvae. However, a RAS for marine larvae should probably not include strong disinfection because it leads to a reduction in bacterial numbers, which is likely to result in a destabilization of the microbial community. [Copyright &y& Elsevier]

DNA metabolic processes such as DNA replication, recombination, and repair are fundamentally important for the maintenance of genome integrity and cell viability. Although a large number of proteins involved in these pathways have been extensively studied, many proteins still remain to be identified. In this study, we isolated DNA-binding proteins from Saccharomyces cerevisiae using DNA-cellulose columns. By analyzing the proteins using mass spectrometry, an uncharacterized protein, Cmr1/YDL156W, was identified. Cmr1 showed sequence homology to human Damaged-DNA binding protein 2 in its C-terminal WD40 repeats. Consistent with this finding, the purified recombinant Cmr1 protein was found to be intrinsically associated with DNA-binding activity and exhibited higher affinity to UV-damaged DNA substrates. Chromatin isolation experiments revealed that Cmr1 localized in both the chromatin and supernatant fractions, and the level of Cmr1 in the chromatin fraction increased when yeast cells were irradiated with UV. These results suggest that Cmr1 may be involved in DNA-damage responses in yeast. [ABSTRACT FROM AUTHOR]

Abstract: Photoswitchable hydrotropic solubilization has been investigated by cis–trans isomerization about the olefinic bond of sodium cinnamate (Na-CIN) for various solutes such as cinnamic acid, aspartic acid, curcumin, thymol, and benzocaine. The extent and rate of isomerization depend on the concentration of Na-CIN and temperature. The cis–trans isomerization of Na-CIN by UV irradiation allows recovery of the solute from aqueous Na-CIN solutions, without dilution by water. Extraction of forskolin and curcumin from coleus forskholii and curcuma longa, was also studied for recovery under UV irradiation. [Copyright &y& Elsevier]

Abstract: A controlled UV-light delivery system is envisioned to be built in order to study the stability properties of superconducting strands. The application requires a wave guide from room temperature to cryogenic temperatures. Hydrogen loaded and unloaded polyimide buffered silica–silica 100μm core fibres were tested at cryogenic temperatures. A thermal stress test was done at 1.9K and at 4.2K which shows that the minimal mechanical bending radius for the fibre can be 10mm for testing (transmission was not measured). The cryogenic transmission loss was measured for one fibre to assess the magnitude of the transmission decrease due to microbending that takes place during cooldown. UV-irradiation degradation measurements were done for bent fibres at 4.2K with a deuterium lamp and 355nm pulsed lasers. The irradiation tests show that the fibres have transmission degradation only for wavelengths smaller than 330nm due to the two photon absorption. The test demonstrates that the fibres are suitable for the cryogenic UV applications with 355nm and 70μJ pulsed lasers. [Copyright &y& Elsevier]

Protection of clean aquifers requires radical minimization of water consumption, overall reduction of wastewater and, furthermore, minimization of wastewater loading. Many organic pollutants in wastewater present a specific problem because of their toxicity, bioaccumulation and poor biodegradability. The scope of this paper is to investigate and identify the benefits offered by advanced oxidation processes (AOPs) as destructive methods for treatment of wastewater loaded with recalcitrant organic pollutants. The study was performed on model wastewater containing p-chlorophenol as a representative of organic chemical industry intermediates. Several UV based AOPs were studied: UV, UV/H 2O 2, UV/O3, UV/H 2O 2/O 3 and UV/Fenton. Optimal process conditions for the highest mineralization efficiency in the investigated range (pH, [H 2O 2] and [Fe 2+]) have been determined on the basis of HPLC measurements and the following ecological parameters: total organic carbon (TOC), adsorbable organic halides (AOX), chemical oxygen demand (COD) and biochemical oxygen demand (BOD 5). Toxicity is one of the most important ecological parameters in determining the level of water pollution. In this study, toxicity tests were performed on the zooplankton Daphnia magna in order to evaluate efficiency of the applied treatments. The UV/ Fenton and UV/H 2O 2/O 3 processes were found to be the most appropriate processes for degradation and mineralization of p-chlorophenol. Complete degradation was achieved after 15 minutes of UV/Fenton process treatment, while 92.1% TOC and 98.3% AOX removals were obtained after treatment of 60 minutes. [ABSTRACT FROM PUBLISHER]

Aqueous solutions of simazine (SIM, 1-chloro-3,5-bisethylamino-2,4,6-triazine; 2,4-bis(ethylamino)-6-chloro-s-triazine) were photolyzed (λ = 254 nm) under a variety of solution conditions. The initial SIM concentration ranged from 69 to 315 µg/L to approach the typical concentration found in contaminated surface waters. The effects of the initial concentration of hydrogen peroxide (H2O2), initial concentration of SIM, pH values, light intensity and different water quality to the degradation of SIM were investigated in the study. The most favorable reaction conditions appear to be a moderate concentration of 120 mg/L H2O2 for the highest removal of simazine. In addition, the experimental results show the initial concentration of SIM has little effect on the removal of SIM. The time-dependent degradation profiles of SIM were successfully modeled using an approximation of the pseudo first-order equation and the kinetic parameters were determined. [ABSTRACT FROM AUTHOR]

Abstract: Background: Dysregulation of microRNA (miRNA) expression is regularly found in various types of cancer and contributes to tumorigenic processes. However, little is known about miRNA expression in non-melanoma skin cancer in which a pathogenic role of beta human papillomaviruses (HPV) is discussed. A carcinogenic potential of beta HPV8 could be demonstrated in a transgenic mouse model, expressing all early genes of HPV8 (HPV8-CER). A single UVA/B-dose induced oncogene expression and led to papilloma growth within three weeks. Objective: Expression of miRNAs and their targets during HPV8-mediated tumor formation in mice. Methods: Skin of untreated or UV-irradiated wild-type and HPV8-CER mice was analyzed for miRNA expression and localization by qPCR and in situ hybridization. MiRNA target protein expression was analyzed by immunohistochemical staining. Results: Early steps in skin tumor formation in HPV8-CER mice were associated with an upregulation of the oncogenic miRNA-17-5p, -21 and -106a and a downregulation of the tumor-suppressive miRNA-155 and -206, which could be demonstrated by qPCR and in situ hybridization. The respective targets of miRNA-21 and -106a, the tumor suppressors PTEN, PDCD4 and Rb with their pivotal role in cell cycle regulation, apoptosis and proliferation were found to be downregulated. Conclusion: This is the first report demonstrating that a cutaneous HPV type deregulates the expression of miRNAs. These deregulations are closely related to the UV-induced upregulation of HPV8 oncogene levels, which suggest a direct or indirect HPV8-specific effect on miRNA expression. These data presume that HPV8 interferes with the miRNA mediated gene regulation to induce tumorigenesis. [Copyright &y& Elsevier]

Polybrominated diphenyl ethers (PBDEs) are frequently detected in food and environmental samples. We used compound specific isotope analysis to determine the δ13C values of individual PBDEs in two technical mixtures. Within the same technical product (DE-71 or DE-79), BDE congeners were the more depleted in 13C the higher brominated they were. In contrast, the products of light-induced hydrodebromination of BDE 47 and technical DE-79 were more enriched in 13C because of more stable bonds between 13C and bromine. As a result, the δ13C values of the irradiated solution progressed diametrically compared to those of the technical synthesis. The ratio of the δ13C values of BDE 47 to BDE 99 and of BDE 99 to BDE 153 are thus suggested as indicators to distinguish native technical products from transformation products. Ratios <1 are typical for native congeners (e.g. in DE-71) while the reversed ratio (>1) is typical of transformation products. [Copyright &y& Elsevier]

Abstract: The article analyzes new and previously reported data on several catalytic and photochemical processes yielding biologically important molecules. UV-irradiation of formaldehyde aqueous solution yields acetaldehyde, glyoxal, glycolaldehyde and glyceraldehyde, which can serve as precursors of more complex biochemically relevant compounds. Photolysis of aqueous solution of acetaldehyde and ammonium nitrate results in formation of alanine and pyruvic acid. Dehydration of glyceraldehyde catalyzed by zeolite HZSM-5-17 yields pyruvaldehyde. Monosaccharides are formed in the course of the phosphate-catalyzed aldol condensation reactions of glycolaldehyde, glyceraldehyde and formaldehyde. The possibility of the direct synthesis of tetroses, keto- and aldo-pentoses from pure formaldehyde due to the combination of the photochemical production of glycolahyde and phosphate-catalyzed carbohydrate chain growth is demonstrated. Erythrulose and 3-pentulose are the main products of such combined synthesis with selectivity up to 10%. Biologically relevant aldotetroses, aldo- and ketopentoses are more resistant to the photochemical destruction owing to the stabilization in hemiacetal cyclic forms. They are formed as products of isomerization of erythrulose and 3-pentulose. The conjugation of the concerned reactions results in a plausible route to the formation of sugars, amino and organic acids from formaldehyde and ammonia under presumed ‘prebiotic’ conditions. [Copyright &y& Elsevier]

The effects of wild type and UV-irradiated lemon balm ( Melissa officinalis) ethanolic extracts (MOE and UMOE) on melanogenesis in vitro were examined. UMOE showed potent antioxidant activity and significantly inhibited the mushroom and melanocyte tyrosinase activity, and lowered cellular melanin content by 49% at 200 μg/mL in B16-F1 melanocytes. The key gene and protein expression of tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 were reduced (−73% for TRP-1 protein at 200 μg/mL UMOE, p<0.05). MOE showed similar results to a slightly lesser degree. We found that myo-inositol, a major compound in lemon balm extracts, significantly reduced cellular melanin synthesis and its effect was greater than arbutin at 1 mM. These suggest that both MOE and UMOE have anti-melanogenic role by both direct inhibition of tyrosinase and down-regulation of gene expressions in melanogenesis. UV-irradiation slightly improved the anti-melanogenic activities. UMOE may be useful as natural anti-melanogenic biomaterials for functional foods and cosmetics. [ABSTRACT FROM AUTHOR]

Abstract: A new synthetic route was utilized for the formation of size-selective Ag nanoparticles (NPs) exploiting UV-irradiation techniques. The one step process exclusively generates Ag NPs of smaller sizes, larger sizes and aggregated nanostructures. The reduction of Ag(I) was done in the presence of adenosine tri-phosphate (ATP) under 30min of UV-irradiation. ATP served as a dual role, a reducing agent and a stabilizing agent for the formation of Ag NPs. The mechanisms of the particle formation and the effects of different reaction parameters were studied in details. The synthesized particles were stable for more than a month under ambient condition without indication of oxide formation. Moreover, the method did not need any harsh reduction conditions. The synthesized negatively charged ATP–Ag NPs has been mixed with bacteria Escherichia coli and studied their interaction. Finally a comparative study was made with the ATP–Ag NPs with positively charged CTAB–Ag NPs. The results indicated that positively charged Ag NPs deposited better with the bacterium surface compared to the negatively charged. The present research might find important applications for the synthesis of other nanomaterials as well as to understand the interactions of NPs with microorganisms. [Copyright &y& Elsevier]

The stabilities and antioxidant action of two selected flavonoids, quercetin and rutin, dissolved in methanol and water, toward continuous UV-irradiation from three different sub-ranges (UV-A, UV-B and UV-C) were studied. The flavonoids underwent degradation (bleaching) following first-order kinetics. The bleaching rates were highly dependent on the energy input of the involved UV-photons. The antioxidant activities of the two flavonoids on UV-induced lecithin lipid peroxidation were studied by the thiobarbituric acid-malondialdehyde (TBA-MDA) test, and appeared to be also affected by the continuous UV irradiation. The energy input of the incident UV-photons again played a major governing role, but an impact of the flavonoids structures cannot be neglected. [ABSTRACT FROM AUTHOR]

The article presents a study on the protective effect of fucoxanthia against UVB-induced skin photoaging in hairless mice. It notes on the formation of wrinkles in UVB-irritated skin observed in the dorsal skin of the mice along with the topical treatment with fucoxanthin estimating by skin replica images. Therefore, findings showed that topical treatment with fucoxanthin that would prevent skin photoaging in UVB-irrated hairless mice.

Abstract: A highly swelling nanoporous hydrogel (NPH) was synthesized via UV-irradiation graft copolymerization of acrylic acid (AA) onto salep backbone and its application as a carrier matrix for colonic delivery of tetracycline hydrochloride (TH) was investigated. Optimized synthesis of the hydrogel was performed by the classic method. The swelling behavior of optimum hydrogel was measured in different media. The hydrogel formation was confirmed by Fourier transform infrared spectroscopy (FTIR) and thermo-gravimetric analysis (TGA/DTG/DTA). The study of the surface morphology of hydrogels using SEM showed a nanoporous (average pore size: about 350nm) structure for the sample obtained under optimized conditions. The drug delivery results demonstrated that this NPH could successfully deliver a drug to the colon without losing the drug in the stomach, and could be a good candidate as an orally administrated drug delivery system. [Copyright &y& Elsevier]

omic force microscopy (AFM) has been used to study the effect of various photoinitiators doped into poly(methyl methacrylate) (PMMA) on the mechanical properties of PMMA films at the nanometer scale. Pure and modified PMMA films (containing four different photoinitiators) were exposed to a mercury vapor lamp in air atmosphere. Force-distance curves for hardness, Young modulus, and adhesion forces were obtained using different AFM modes (tapping or contact-mode) and different tips (diamond or silicon nitride). The results revealed that the added photoinitiators slightly changed the nanomechanical properties of PMMA as a result of alterations in the photochemical reactions and physical processes occurring in the studied systems. tert-Butyl peroxybenzoate had the most efficient effect on the measured parameters in UV-irradiated PMMA, whereas benzoyl peroxide was less active. The mechanism of the observed processes is discussed. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to study the photocatalytic activity of titanium dioxide (TiO2) against Listeria monocytogenes bacterial biofilm. Different TiO2 nanostructured thin films were deposited on surfaces such as stainless steel and glass using the doctor-blade technique. All the surfaces were placed in test tubes containing Brain Heart (BH) broth and inoculated with L. monocytogenes. Test tubes were then incubated for 10 days at 16°C in order to allow biofilm development. After biofilm formation, the surfaces were illuminated by ultraviolet A light (UVA; wavelength of 315–400nm). The quantification of biofilms was performed using the bead vortexing method, followed by agar plating and/or by conductance measurements (via the metabolic activity of biofilm cells). The presence of the TiO2 nanoparticles resulted in a fastest log-reduction of bacterial biofilm compared to the control test. The biofilm of L. monocytogenes for the glass nanoparticle 1 (glass surface modified by 16% w/v TiO2) was found to have decreased by 3log CFU/cm2 after 90min irradiation by UVA. The use of TiO2 nanostructured photocatalysts as alternative means of disinfecting contaminated surfaces presents an intriguing case, which by further development may provide potent disinfecting solutions. Surface modification using nanostructured titania and UV irradiation is an innovative combination to enhance food safety and economizing time and money. [Copyright &y& Elsevier]

The aim of this work is to estimate the antioxidant activity of β-carotene in the presence of two different mixtures of phospholipids in hexane solution, under continuous UV-irradiation from three different ranges (UV-A, UV-B, and UV-C). β-Carotene is employed to control lipid peroxidation process generated by UV-irradiation, in the presence and in the absence of selected photosensitizer, benzophenone, by scavenging the involved, created free radicals. The results show that β-carotene undergoes to a substantial, probably structural dependent destruction (bleaching), highly dependent on UV-photons energy input, more expressed in the presence than in the absence of benzophenone. The additional bleaching is synchronized with the further increase in β-carotene antioxidant activity in the presence of benzophenone, implying the same cause: increase in (phospholipids peroxidation) chain-breaking activities. [ABSTRACT FROM AUTHOR]

Growth curves in liquid peptone-glucose medium and survival curves of the Saccharomyces cerevisiae culture from variously irradiated inoculum were evaluated. Irradiation of yeast cells in solution physiological (salt) was performed with γ-rays of Co in Gammacell 220 or with UV-irradiation using ultraviolet lamps UVH 1016-6 and Photochemical reactors, Ltd, Sylvania for various time periods. Various dose rates of both types of radiation were used. The absorbed doses reached some hundreds Gy for both γ and UV radiation. The growth curves were measured using the nephelometric data of yeast suspension in various time periods of growth. The results of repeated measurements showed that the slope of growth curves express relatively exactly the negative influence of irradiation when the standard and uniform method of evaluation was used. When the curves were fitted to the data points by the least-squares method, the average standard errors were found to be in the range from 0.6 to 0.8% and from 0.2 to 0.5% for γ- and UV-irradiation, respectively. The negative effect of irradiation depended monotonously and non-linearly on the applied dose of irradiation. Quantitatively different effects were found in the case of γ and UV irradiation. [ABSTRACT FROM AUTHOR]

Abstract: Nanostructured semiconductor architectures have attractive optical properties mainly including bright photoluminescence (PL) resulting from the radiative recombination of charge carriers on surface states. Various approaches have been employed for the modification of surface states of these nanostructures to design new nanomaterials with enhanced PL primarily in aqueous medium to enable their applications in biological samples. Here, we report the varying efficiencies of three commercial surfactants viz. cetyltrimethylammonium bromide (CTAB), cetyltrimethylammonium chloride (CTAC) and cetylpyridinium chloride (CPyC) on the dynamics of PL emission enhancement during initial growth and Ostwald ripening of ZnS nanoparticles (NPs). The counterion has been estimated to behave differently to govern the PL enhancement. The exceptionally high tendency of CPyC in PL enhancement has been assigned to participation of π-electrons of pyridinium ring. The impact of UV-light in photoactivation of surfactant stabilized ZnS NPs has been utilized in exploring significance of surfactants in improving the surface emitting states in water soluble semiconductor NPs. [ABSTRACT FROM AUTHOR]

To develop a rearing programme for the egg parasitoid Trichogrammatoidea lutea for augmentative biological control, the effects of ultraviolet (UV) irradiated host eggs were evaluated on the number of eggs parasitized, development time, number of progeny and sex ratio of T. lutea, using eggs of the lepidopteran species Helicoverpa armigera, Chilo partellus and Cadra cautella as hosts. UV-irradiation of 13 min was sufficient to kill embryos of all three hosts. The highest mean percentage parasitism on UV-irradiated and un-irradiated eggs occurred on those of H. armigera (47.8% and 33.3%) and C. cautella (33.2% and 55.5%), followed by C. partellus (6.6% for both). The mean number of individuals emerged per single parasitized host of UV-irradiated and un-irradiated eggs was highest for H. armigera (2.5 and 2.1) and lower for C. partellus (1.3 and 1.4) and C. cautella (0.9 and 0.8). The sex ratio of T. lutea was female-biased on UV-irradiated eggs of H. armigera, on UV-irradiated and un-irradiated eggs of C. cautella, and male-biased for C. partellus eggs and un-irradiated eggs of H. armigera. The developmental time of T. lutea from egg to adult male and female differed slightly between UV-irradiated and un-irradiated eggs. Overall, UV-irradiation of host eggs had negligible effects on percent parasitism, number of progeny per parasitized egg and sex ratio of T. lutea. Of the three lepidopteran species evaluated, H. armigera appears to be the most suitable host for mass-rearing of T. lutea. The results indicate that UV-irradiation of Lepidoptera eggs is suitable for mass rearing of T. lutea. [ABSTRACT FROM AUTHOR]

n excess of reactive oxygen species (ROS) leads to a variety of chronic health problems. As potent antioxidants, marine bioactive extracts containing oligosaccharides and peptides have been extensively studied. Recently, there is a growing interest in protein-polysaccharide complexes because of their potential uses in pharmaceutical and food industries. However, only few studies are available on the antioxidant activities of such complexes, in terms of their ROS scavenging capability. In this study, we combined different marine oligosaccharides (isolated and purified) with collagen peptides derived from tilapia fish skin, and evaluated the antioxidant activity of the marine peptide-oligosaccharide complexes vis-à-vis the activity of their original component molecules. Biochemical and cellular assays were performed to measure the scavenging effects on 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide radicals, and to evaluate the influences on the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the level of malondialdehyde (MDA) in UV-induced photoaging models. The results indicated that the antioxidant activities of all the complexes were stronger than those of their individual components. Among the 11 complexes tested, two complexes, namely MA1000+CP and κ-ca3000+CP, turned out to be highly effective antioxidants. Although the detailed mechanisms of this improved scavenging ability are not fully understood, this work provides insights into the design of highly efficient peptide-oligosaccharide complexes for potential applications in pharmaceutical, cosmetics and food industries. [ABSTRACT FROM AUTHOR]

Antagonistic capability of Trichoderma harzianum was improved through UV-irradiation. Four different type of mutants, T. harzianum - Ma (Th-Ma), T. harzianum - Mb(Th-Mb), T. harzianum - Mc (Th-Mc), T. harzianum - Md (Th-Md) of T. harzianum and the parent strain (Th-P) were selected for further studies. Th-Ma and Th-Mb showed more antagonistic capability against Macrophomina phaseolina than its parent strain Th-P in dual culture. Biochemical analysis of these four mutants and the parent strain showed that Th-Ma releases higher level of two lytic enzymes i.e. chitinases and cellulases and Th-Mb produces more β-1,3-glucanase activity than the parent strain. Culture filtrate of Th-Ma also showed antifungal properties. Study of the competitive saprophytic ability (CSA) of these four mutants and the parent strain were also made. Th-Ma exhibited higher CSA than the parental isolate while Th-Md had less CSA than all other mutants and the parent strain of T. harzianum. [ABSTRACT FROM AUTHOR]

Abstract: Poly(vinyl alcohol), pectin and their blends with different components ratio were exposed to low-temperature air plasma or high energy UV-irradiation (λ =254nm) for the purpose of surface modification. The physico-chemical changes in surface properties have been studied by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and contact angle measurements. Surface free energy of polymeric films, its polar and dispersive components have been calculated by Owens–Wendt method. Moreover, the work of adhesion was estimated and the recovery of hydrophobic properties of modified films after storage have been also studied. The few seconds air-plasma treatment caused more effective surface modification than 5–6h UV-irradiation. The observed changes were partially reversible, contrary to these caused by photo-modification. It was found that pectin/PVA (50:50) blend was characterised by larger susceptibility to plasma modification compared to pure pectin and pure PVA, whereas the photosensitivity to radiation of 254nm wavelength was the lowest for this specimen in comparison to other studied samples. [ABSTRACT FROM AUTHOR]