Search Results (329)

This study investigated the effect of an apple pectin coating enriched with gamma-decalactone (GDL) on the physicochemical and microbiological quality of strawberries over 9 days of refrigerated storage. Strawberries were coated with pectin solutions containing a plasticizer and emulsifier, with or without GDL, and compared to uncoated controls. The coatings were evaluated for their effects on fruit mass loss, pH, extract content (°Brix), firmness, color parameters (L*, a*, b*, C*, h*, ΔE), and microbial spoilage. The pectin coating limited changes in extract, pH, and color and slowed firmness loss. Notably, GDL-enriched coatings significantly reduced spoilage (14.29% after 9 days vs. 57.14% in the control) despite accelerating pulp softening. Extract content increased the most in the GDL group (from 9.92 to 12.00 °Brix), while mass loss reached up to 22.8%. Principal Component Analysis (PCA) confirmed coating type as a major factor differentiating sample quality over time. These findings demonstrate the potential of bioactive pectin-based coatings to enhance fruit preservation and support the development of active packaging strategies. Further studies should optimize coating composition and control the release kinetics of functional compounds. Full article

Background: The rising demand for aesthetic dental treatments has spurred interest in peroxide-free color correctors as alternatives to traditional hydrogen peroxide formulations, which are associated with tooth sensitivity and potential enamel demineralization. This systematic review evaluates the whitening efficacy and safety profile of hydrogen peroxide-free color corrector (HPFCC) products, focusing on color change metrics, enamel and dentin integrity, and adverse effects. Methods: Following PRISMA guidelines, we searched PubMed, Scopus, and Web of Science throughout January 2025 for randomized controlled trials, observational studies, and in vitro experiments comparing HPFCC to placebo or peroxide-based agents. The data extraction covered study design, sample characteristics, intervention details, shade improvement (ΔE00 or CIE Lab), enamel/dentin mechanical properties (microhardness, roughness, elastic modulus), and incidence of sensitivity or tissue irritation. Risk of bias was assessed using the Cochrane tool for clinical studies and the QUIN tool for in vitro research. Results: Six studies (n = 20–80 samples or subjects) met the inclusion criteria. In vitro, HPFCC achieved mean ΔE00 values of 3.5 (bovine incisors; n = 80) and 2.8 (human molars; n = 20), versus up to 8.9 for carbamide peroxide (p < 0.01). Across studies, HPFCC achieved a mean ΔE00 of 2.8–3.5 surpassing the perceptibility threshold of 2.7 and approaching the clinical acceptability benchmark of 3.3. Surface microhardness increased by 12.9 ± 11.7 VHN with HPFCC (p < 0.001), and ultramicrohardness rose by 110 VHN over 56 days in prolonged use studies. No significant enamel erosion or dentin roughness changes were observed, and the sensitivity incidence remained below 3%. Conclusions: These findings derive from one clinical trial (n = 60) and five in vitro studies (n = 20–80), encompassing violet-pigment serums and gels with differing concentrations. Due to heterogeneity in designs, formulations, and outcome measures, we conducted a narrative synthesis rather than a meta-analysis. Although HPFCC ΔE00 values were lower than those of carbamide peroxide, they consistently exceeded perceptibility thresholds while maintaining enamel integrity and causing sensitivity in fewer than 3% of subjects, supporting HPFCCs as moderate but safe alternatives for young patients. Full article

The sapwood and heartwood of European larch (Larix decidua Mill.) are both used in industrial applications, but they differ in structure and composition, which may lead to surface property differences. This study compared their surface characteristics (on radial and tangential sections) after sanding with aluminium oxide papers of four grit sizes (P60, P120, P180, P240). Surface roughness (Ra, Rz), wettability (contact angle with two reference liquids: water and diiodomethane, 3 and 30 s after droplet deposition), surface free energy, and colour parameters (L*, a*, b*) were analysed. Microscopic measurements were also performed to assess anatomical differences between sapwood and heartwood. The results showed no significant differences in roughness (Ra, Rz) between sapwood and heartwood. Measurement direction and sandpaper grit accounted for about 80% of variability in roughness parameters. Wettability was mainly influenced by wood area, with its effect ranging from 55% to 89% depending on measurement time. The sapwood was characterised by the lower wettability on the tangential section, while the heartwood was characterised by the lower wettability on the radial section. This was examined for the contact angle tests performed 3 s after the water droplet had been applied to the wood surface. Such dependencies were not observed after 30 s. Sapwood exhibited higher surface free energy (SFE) values than heartwood. The greatest colour change ΔE, at level 2.59, was noted for the heartwood on the radial section after sanding with P240 sandpaper. Full article

Quadcolor cameras with conventional RGB channels were studied. The fourth channel was designed to improve the estimation of the spectral reflectance and chromaticity from the camera signals. The RGB channels of the quadcolor cameras considered were assumed to be the same as those of the Nikon D5100 camera. The fourth channel was assumed to be a silicon sensor with an optical filter (band-pass filter or notch filter). The optical filter was optimized to minimize a cost function consisting of the spectral reflectance error and the weighted chromaticity error, where the weighting factor controls the contribution of the chromaticity error. The study found that using a notch filter is more effective than a band-pass filter in reducing both the mean reflectance error and the chromaticity error. The reason is that the notch filter (1) improves the fit of the quadcolor camera sensitivities to the color matching functions and (2) provides sensitivity in the wavelength region where the sensitivities of RGB channels are small. Munsell color chips under illuminant D65 were used as samples. Compared with the case without the filter, the mean spectral reflectance rms error and the mean color difference (ΔE₀₀) using the quadcolor camera with the optimized notch filter reduced from 0.00928 and 0.3062 to 0.0078 and 0.2085, respectively; compared with the case of using the D5100 camera, these two mean metrics reduced by 56.3%. Full article

This study investigates the effects of repeated mechanical recycling on the structural, thermal, mechanical, and aesthetic properties of poly(butylene succinate) (PBS), a commercially available bio-based and biodegradable aliphatic polyester. PBS production scraps were subjected to five consecutive recycling cycles through semi-industrial extrusion compounding followed by injection molding to simulate realistic mechanical reprocessing conditions. Melt mass-flow rate (MFR) analysis revealed a progressive increase in melt fluidity. Initially, the trend of viscosity followed the melt flow rate; however, increasing the reprocessing number (up to 5) resulted in a partial recovery of viscosity, which was caused by chain branching mechanisms. The phenomenon was also confirmed by data of molecular weight evaluation. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) confirmed the thermal stability of the polymer, with minimal shifts in glass transition, crystallization, and degradation temperatures during the reprocessing cycles. Tensile tests revealed a slight reduction in strength and stiffness, but an increase in elongation at break, indicating improved ductility. Impact resistance declined moderately from 8.7 to 7.3 kJ/m² upon reprocessing; however, it exhibited a pronounced reduction to 1.8 kJ/m² at −50 °C, reflecting brittle behavior under sub-ambient conditions. Despite these variations, PBS maintained excellent color stability (ΔE < 1), ensuring aesthetic consistency while retaining good mechanical and thermal properties. Full article

This study focuses on the stabilization of a natural hair dye derived from Lawsonia inermis L. (henna) and Indigofera suffruticosa (indigo). Although various formulations already exist, they are designed for immediate use and cannot be stored. Lawsonia, a primary component of the dye, tends to degrade after release. To ensure its stability, freeze-drying was implemented as a protective measure. Colorimetric analysis confirmed the dye’s ability to maintain an intense, uniform coloration even after multiple washing cycles. Stability tests demonstrate that freeze-drying effectively enhances the dye’s stability and capacity to retain its physical properties and color under various environmental conditions, demonstrating its potential for long-term use. The dye’s pH (5.05) aligns with the natural pH of hair, promoting cuticle sealing and improving hair health. Cytotoxicity tests confirmed the dye’s safety, showing no harmful effects. Gray hair exhibited a total color difference (ΔE) of 64.06 after the initial application, using natural gray hair as a reference. By the third application, ΔE increased to 69.86 and gradually decreased to 68.20 after 15 washing cycles, highlighting its long-term durability. Gray hair exposed to 720 h of UV radiation showed a ΔE of 17.34, whereas dyed gray hair exhibited a ΔE of 2.96 compared to non-UV-exposed samples. This indicates superior resistance to color degradation in dyed hair. Also, SEM imaging revealed the dye’s restorative effects, progressively improving hair cuticle structure with each application. Full article

Background/Objectives: Tooth discoloration is a common concern associated with the use of intra-canal medicaments, particularly those containing antibiotics. This study aims to evaluate the tooth discoloration potential of an experimental antibiotic paste modified with Nano Chitosan (APNC) and compare it with two antibiotic pastes and two calcium hydroxide-based pastes over different time intervals. Methods: Fifty bovine incisors were standardized and prepared up to size 60. The teeth were randomly assigned into five groups based on the medicament applied: Metapaste, Metapex, modified Triple Antibiotic Paste (mTAP), Double Antibiotic Paste (DAP), and APNC. A digital spectrophotometer was used to measure the color parameters (L*, a*, and b*) at two zones, above and below the cemento-enamel junction (CEJ), across four-time points: before application (T0- baseline), immediately after application (T1), after two weeks (T2), and after one month (T3). The color changes (ΔE) were calculated and statistically analyzed using repeated-measure ANOVA. Results: Statistically significant differences in discoloration were observed between the tested medicaments after one month (p < 0.05). mTAP caused the highest ΔE values both above and below the CEJ at all time points, particularly after one month (p < 0.05). Conversely, APNC, Metapaste, and DAP demonstrated the least discoloration, with no significant differences among them. The degree of discoloration was time-dependent and more pronounced below the CEJ in all groups. Conclusions: After one month, the experimental APNC paste induced tooth discoloration comparable to that of Metapaste, indicating minimal esthetic compromise. APNC may be a promising alternative to traditional antibiotic pastes with minimal discoloration effects. Full article

Tooth bleaching is a widely used esthetic treatment; however, bleaching agents can temporarily alter the surface morphology of enamel, increasing surface roughness and porosity, which may lead to increased susceptibility to discoloration. This in vitro study investigated the effectiveness of fluoride varnish in preventing immediate discoloration of bovine incisors after bleaching. Specimens were bleached with 35% hydrogen peroxide and treated with either Clinpro White Varnish (CW) or Enamelast Fluoride Varnish (EN), whereas control specimens received no treatment after bleaching. The samples were immersed in coffee for 24 h, and the color difference (ΔE₀₀) was calculated using the CIEDE2000 formula. The surface morphology of enamel was examined using SEM. The fluoride varnish groups showed significantly lower color difference values than the control group (p < 0.05), with ΔE₀₀ reduced by approximately two-thirds in both the CW and EN groups. SEM observations showed that the enamel surfaces in the varnish-treated groups exhibited reduced surface irregularities compared to the untreated group, suggesting remineralization. These results suggest that the immediate application of fluoride varnish after bleaching can effectively reduce short-term discoloration by providing physical protection and promoting remineralization. Fluoride varnish may serve as a simple and effective strategy to maintain whitening outcomes and minimize early discoloration. Full article

Background/Objectives: Tooth bleaching is a widely requested aesthetic procedure in modern dentistry. However, the structural effects of high-concentration peroxide-based bleaching agents on enamel remain insufficiently understood. This study aims to evaluate and compare the effects of three in-office bleaching agents—Opalescence Boost (40% hydrogen peroxide [HP]), Opalescence Quick (45% carbamide peroxide [CP]), and BlancOne Ultra + (35% hydrogen peroxide [HP])—on enamel surface characteristics and color change using confocal laser scanning microscopy (CLSM) and spectrophotometric analysis. Methods: Forty-two extracted human teeth were sectioned and divided into experimental and control halves. Each experimental specimen underwent bleaching according to the manufacturer’s protocol. Color measurements were conducted at baseline, immediately post-treatment, at 3 days, 7 days, and 6 months following treatment using the Vita Easyshade^® spectrophotometer. Color differences were calculated using the CIEDE2000 (ΔE₀₀) formula. Enamel surface morphology was assessed by CLSM. Data were analyzed using Wilcoxon and Kruskal–Wallis tests (p < 0.05), performed with SPSS v23. Results: All bleaching agents produced clinically perceptible color changes (ΔE₀₀ > 3.3). Opalescence Boost achieved the highest and most consistent whitening effect (mean ΔE₀₀ > 11), while Opalescence Quick showed moderate efficacy (ΔE₀₀ ~6–8), and BlancOne Ultra+ induced milder changes (ΔE₀₀ ~4–5). CLSM imaging revealed surface alterations in all bleached samples, with more pronounced changes observed in specimens treated with higher peroxide concentrations. Conclusions: All three bleaching systems were effective in improving enamel color, with Opalescence Boost delivering the most substantial and durable effect. CLSM analysis confirmed morphological changes in enamel without evidence of severe damage. These results underscore the importance of selecting bleaching protocols that balance efficacy with enamel safety. Further in vivo studies are recommended to validate long-term structural effects and support clinical decision-making. Full article

Intelligent films (IFs) incorporating natural colorants and biodegradable materials offer innovative solutions for monitoring food freshness and spoilage. This study evaluated the impact of varying the PVA-APN ratio on films formulated with Peruvian Purple Potato starch (APN) and anthocyanin extract (AE). The research focused on the effects of PVA on physicochemical and mechanical characteristics, as well as the color changes observed when the films were used with seafood. The results indicated a decrease in chroma a* and an increase in chroma b* when the films were in contact with different buffer solutions (from acidic to alkaline). Solubility decreased with higher starch concentrations and the mechanical properties revealed a reduced tensile strength and elongation with increased APN concentration. The films effectively indicated freshness, with the best ΔE values for the 50:50 formulations (13.6 ± 1.6 and 12.04 ± 2.8 for fish and shrimp, respectively), making them promising candidates for intelligent seafood packaging. Full article

The new generation of food packaging should not only be biodegradable, but also provide additional protective properties for packaged products, extending their shelf life. In this paper, we present the results of research on cast-extruded poly(butylene succinate) (PBS) films coated with hydroxypropyl methylcellulose (HPMC) modified with CO₂ extract from sea buckthorn (ES) or its ethosomes (ET) at amounts of 1 or 5 pph per HPMC. In addition, the developed films were exposed to accelerated aging (UV radiation and elevated temperature) to determine its effect on the films’ properties. Based on SEM, it can be concluded that accelerated aging results in the uncovering of the extract and ethosomes from the coating’s bulk. GPC showed a decrease in the molecular weight of PBS after treatment, additionally amplified by the presence of HPMC. However, the addition of ES or ET in low concentrations reduced the level of polyester degradation. The presence of the modified coating and its treatment increased the oxygen barrier (a decrease from 324 cm³/m² × 24 h for neat PBS to 208 cm³/m² × 24 h for the coated and modified PBS ET5). Despite the presence of colored extract or ethosomes in the coating, the color differences compared with neat PBS were imperceptible (ΔE < 1). The addition of 5 pph of sea buckthorn extract or its ethosomes in combination with accelerated aging resulted in the complete inhibition of the growth of E. coli and S. aureus, which was not observed in non-aged samples. The results obtained demonstrate an improvement in bioactive properties and protection against the negative effects of UV radiation on the film due to the presence of ET or ES in the coating. The developed systems could be used in the food industry as active packaging. Full article

The aim was to assess the blending effect of universal-shade resin-based composites (RBCs) (Omnichroma—OC; Clearfil Majesty Universal–CM; Venus Pearl—V; Transcend—T) used for repair for lithium disilicate blocks. Fifteen parallelepiped-shaped (10.5 × 10.5 × 3 mm) specimens with four cavities (3 mm in diameter and 2 mm in depth) were designed from lithium disilicate CAD/CAM blocks (CEREC Tessera HT A3) and milled. Specimens were then randomly divided into five groups based on the five resin composite materials for cavity restoration (n = 12): Group 1, control group (F); Group 2 (T); Group 3 (OC); Group 4 (V); and Group 5 (CM). After surface conditioning, composite resins were applied to the ceramic surface. Color measurements were taken with a colorimeter in the center of the resin restoration and on the CAD/CAM block. Tristimulus values were converted to CIELab color coordinates and color differences were expressed in ΔE₀₀ units using the CIEDE-2000 formula. F showed significantly better color matching (ΔE₀₀ = 2.51 ± 0.64) in comparison to single-shade RBCs except T (ΔE₀₀ = 2.55 ± 0.64). All groups exceeded perceptibility and acceptability thresholds. The control group presented higher color matching than the single shade universal composites except for Transcend. Full article

Auricularia (wood ear fungus) is susceptible to Burkholderia gladioli pv. cocovenenans (BGC) and causes food poisoning. This study investigated pulsed-light (PL) inactivation of BGC on Auricularia. The evaluation of PL parameters indicated that lower initial biomass, shorter distance, and more fluences were more effective in inactivating BGC. This study achieved 5~8 Log reductions in BGC in phosphate-buffered saline and ~4 Log reductions in Auricularia auricula and Auricularia cornea var. Li, and the survivor curves fit the Weibull model well with R² values of 0.943~0.987 and RMSE values of 0.308~0.430 in all three substrates. PL caused cell membrane damage, leading to DNA, protein, and ATP leakage and increased ROS production. PL caused an alteration in color (ΔE 3.01~7.67) but not springiness and cohesiveness in the texture of Auricularia at 11.80~35.40 J/cm². In all, PL is effective in inactivating BGC on the surface of Auricularia at 35.40 J/cm² and can be taken as a good controlling measure. Full article

Photosensitizers with high singlet oxygen (¹O₂) generation capacity under near-infrared (NIR) irradiation are essential and challenging for photodynamic therapy (PDT). A simple yet effective molecular design strategy is realized to construct 1 + 1 > 2 photosensitizers with synergistic effects by covalently integrating iridium complexes with cyanine via ether linkages, as well as introducing aldehyde groups to suppress non-radiative decay, named CHO−Ir−Cy. It is demonstrated that CHO−Ir−Cy successfully maintains the NIR absorption and emission originated from cyanine units and high ¹O₂ generation efficiency from the iridium complex part, which gives full play to their respective advantages while compensating for shortcomings. Density functional theory (DFT) calculations reveal that CHO−Ir−Cy exhibits a stronger spin–orbit coupling constant (ξ (S1, T1) = 9.176 cm⁻¹) and a reduced energy gap (ΔE = −1.97 eV) between triplet excited states (T₁) and first singlet excited states (S₁) compared to parent Ir−Cy or Cy alone, directly correlating with its enhanced ¹O₂ production. Remarkably, CHO−Ir−Cy demonstrates superior cellular internalization in 4T1 murine breast cancer cells, generating substantially elevated ¹O₂ yields compared to individual Ir−Cy/Cy under 808 nm laser irradiation. Such enhanced reactive oxygen species production translates into effective cancer cell ablation while maintaining favorable biocompatibility, significant phototoxicity and negligible dark toxicity. This molecular engineering strategy overcomes the inherent NIR absorption limitation of traditional iridium complexes and ensures their own high ¹O₂ generation ability through dye–metal synergy, establishing a paradigm for designing metal–organic photosensitizers with tailored photophysical properties for precision oncology. Full article

This study explored the extraction of genistein-7-O-[α-rhamnopyranosyl-(1→6)]-β-glucopyranoside (GTG) from Derris scandens using an aqueous-ethanol solvent system, aiming to optimize yield and antioxidant activity. Hansen solubility parameters (HSP) were employed to determine the optimal solvent composition, with the highest GTG yield (6.83 ± 0.06 mg/g dried weight) obtained from 50% ethanol—correlating well with HSP predictions. Ultrasonic extraction was most effective with solvents having a dielectric constant between 50 and 60. The antioxidant potential of isolated GTG was evaluated using the DPPH assay, which yielded an IC₅₀ of 87.86 ± 1.85 μM, and the FRAP assay, with a value of 34.23 ± 2.75 mg FeSO₄ equivalents. Molecular orbital analysis revealed HOMO and LUMO energy gaps (ΔE = 10.6715 eV) similar to known antioxidants such as gallic acid, ascorbic acid, Trolox, and quercetin. These findings demonstrate that HSP effectively guided solvent selection for ultrasound-assisted extraction of GTG. The antioxidant activity is attributed to GTG’s capacity to donate electrons and stabilize radicals via extended charge delocalization within the aglycone structure, confirming its potential as a natural antioxidant agent. Full article