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The high solar reflectance and good colour performance are requisite for the practical application of the colour-cool pigment. In this work, Ce-doped Yb 3 Al 5 O 12 and (Y, Yb) 3 Al 5 O 12 ceramic pigments were prepared by the sol-gel method. Both Ce3+ and Ce4+ ions coexist in the doped pigments. Due to the 4f→5d electron transition of Ce3+, the Ce-doped pigments have a selective absorption at around 400–520 nm, which is responsible for the yellow hue. The content of the Ce3+ ion determines the colour performance of the pigment. The size effect from the smaller Yb3+ ion results in an increased content of Ce3+ in the Ce-doped pigments, leading to an improved colour performance. The incorporation of Y3+ ion can effectively decrease the absorption at 975 nm, thereby enhancing the solar reflectance to 80.6 %, while maintaining good colour performance (Yb 0.7 Y 2.1 Ce 0.2 Al 5 O 12 , L* = 91.40, a* = -4.89, b* = 45.33). In a simulation experiment, the ceramic glaze coating based on the prepared pigment showed a temperature reduction of 5.2 °C compared to the commercial yellow pigment ceramic coating. [ABSTRACT FROM AUTHOR]

Understanding the process of color development and creating practical and efficient blue pigments is crucial in ceramics. The current work describes the synthesis and characterization of Ni2+-doped Zn 2 GeO 4 samples with varying concentrations (x = 0, 0.01, 0.02, 0.04, 0.08 and 0.16 mol%) as an effective strategy for tailoring their structure and electronic properties. These materials were synthesized using the coprecipitation method followed by microwave-assisted hydrothermal treatment at 140 °C for 10 min, and the as-synthesized samples underwent heat treatment at 1000 °C for 2 h to establish thermal-colorimetric stability. The synergistic effect of the Ni2+ 3d orbitals generating energy levels as new trapping sites in a broad energy range above the valence band was verified using DFT calculations. The substitution of Zn2+ by Ni2+ at x = 0.01 % changes the local electronic structure, resulting in a switchable electron transfer from the [NiO 4 ] and the neighbor [ZnO 4 ]and [GeO 4 ] tetrahedral clusters to shared oxygen anions, which is responsible for the observed blue color, as confirmed by colorimetric and spectroscopic analysis. This study paves the way, shedding light on the strategic design of a new class of ceramic pigments characterized by low toxicity, a vibrant blue hue, and excellent chemical/thermal durability. Furthermore, it provides a robust platform for exploring its potential application in the color-tunable Zn 2 GeO 4 -based materials. [ABSTRACT FROM AUTHOR]

Yellow ochre commercial oil paint used in art and restoration was submitted to accelerated aging at 378 K between 5–720 h. SEM-EDS analysis shows particles with size in the range of 1.4–2.5 μm with high iron concentration in the paint aged from 360 h. EPR spectra showed a variation of g values between 2.2256 and 2.1719 (Fe3+) for samples aged 5–720 h, respectively, attributed to changes in the goethite chemical environment. Infrared analysis showed the presence of carboxylate groups in the aged material as the result of the molecular interaction between the product of linseed oil hydrolysis (palmitate) and the goethite surface through hydrogen bonding (R–C–OO⋯H–O–FeO). Such data is also supported by the Zeta potential of the pigment surface, which decreased as a function of aging time. The results show the change in the chemical environment of goethite is proportional to the increase in oil oxidation/hydrolysis products. The EPR and Zeta potential proved to be promising for the study of the molecular interactions in oil painting aging and can be used for new pigment/media formulations and for proposing new materials aimed at inhibiting the hydrolytic/oxidative processes of oil paints. [ABSTRACT FROM AUTHOR]

We report a patient with isolated stromal lipofuscinosis of the seminal vesicle, a rare entity characterized by intracytoplasmic pigmented granules within stromal cells intimately surrounding seminal vesicle epithelium. Only 4 patients with this unusual phenomenon have been previously reported in the literature. Recognizing this incidental and presumably non-pathologic finding is important to prevent misclassification as a more concerning lesion. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to the low-temperature synthesis of cobalt-containing diopside pigments based on granulated blast furnace slag and to study the characteristics of the mineral formation processes, changes in the structure and colour indices. Design/methodology/approach: Synthesis of cobalt-containing diopside pigments based was carried out by the directional formation of the mineralogical composition with the introduction of part of the components using granulated blast-furnace slag. Findings: It has been established that the formation of the diopside phase in pigments containing blast-furnace slag as the main component proceeds at low temperatures (1,100°C–1,150 °C). The colour of diopside pigments is formed because of the isomorphic substitution of Si4+ ions for Al3+ ions and Mg2+ ions for Co2+ ions. It is expedient to add CoO in an amount of 0.9 mol (18 Wt.%) into the composition of diopside pigments based on blast-furnace slag to obtain defect-free violet glazes. Practical implications: The developed diopside pigments enable obtaining of high-quality violet glazes for ceramics. The application of the obtained results can significantly reduce the consumption of traditional raw materials in the composition of silicate ceramic pigments, as well as reduce their firing temperature. Originality/value: Calcium, magnesium and silicon oxides are the main components of blast-furnace slag. In addition, granulated blast furnace slag is mainly represented by the glassy phase, which determines its high activity during the firing process. These factors are prerequisites for using the blast-furnace slag as a valuable substitute for chemically pure or natural raw materials in silicate pigments and reducing their firing temperature. [ABSTRACT FROM AUTHOR]

It is known that floriculture is very important for the world economic scenario. Nevertheless, the vase life of cut flowers is determined by a short time span. This study evaluated the spectral behavior during leaf degradation of lisianthus (Eustoma grandiflorum) flower stems in the postharvest, in different preservative solutions, and estimating its leaf pigments by hyperspectral data. Lisianthus floral stems were subjected to preservative solutions with different concentrations of sucrose, glucose, phytohormones and deionized water. Leaves from these stems were collected every 4 days for further hyperspectral analysis. Spectra was determined in laboratory with a sensor collecting at the range of 350-2500 nm. In order to analyze the use of the spectra to detect the performance of the preservative solutions, statistical tests were used at each wavelength. Pigment prediction was assessed by the CAR/CLF ratio (Ratio between Carotenoids and Chlorophyll) from the spectral curves, using PLSR and RRMSE. The glucose-based solutions registered positive effects on the preservation of floral stems, especially at the dose of 180 g/L. The solutions based on sucrose and phytohormones registered similarities in the spectral curves among the doses, demonstrating equality in leaf preservation. The discriminant analyses demonstrated there was statistical difference in the spectral responses in the doses for each solution used. The CAR/CLF ratio had reasonable coefficients of 0.6 and RRMSE below 6.99%. The hyperspectral analyses presented a potential for the evaluation of leaf degradation in lisianthus floral stems in different pulsing solutions used in the postharvest. [ABSTRACT FROM AUTHOR]

BACKGROUND: The drive towards ensuring the sustainability of bioresources has been linked with better valorising primary materials and developing biorefinery pipelines. Seaweeds constitute valuable coastal resources with applications in the bioenergy, biofertiliser, nutrition, pharmaceutical and cosmetic sectors. Owing to the various sought‐after metabolites they possess, several seaweed species are commercially exploited throughout Western Europe, including Ireland. Here, four commercially relevant brown (Fucus serratus and Fucus vesiculosus) and red (Chondrus crispus and Mastocarpus stellatus) seaweed species were sampled during a spring tide in July 2021 on moderately exposed shores across three coastal regions in the west of Ireland. RESULTS: Significant regional differences were identified when specimens were analysed for carbohydrates (max. 80.3 μg glucose eq mg−1 DW), proteins (max. 431.3 μg BSA eq. mg−1 DW), lipids (max. 158.6 mg g−1 DW), pigment signature and antioxidant potential. Protein content for F. serratus recorded a twofold difference between northern and southern specimens. The antioxidant potential of F. vesiculosus and M. stellatus returned greater activity compared to F. serratus and C. crispus, respectively. Multivariate analysis showed a clear latitudinal pattern across the three western coastal regions (north, west and south) for both F. vesiculosus and F. serratus. CONCLUSION: F. vesiculosus thalli from the northwest were richer in pigment content while the F. serratus thalli from the northwest were richer in antioxidants. Such biogeographic patterns in the biochemical make‐up of seaweeds need consideration for the development of regional integrated aquaculture systems and the optimisation of the biomass content for targeted downstream applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This research focuses on the development of thermochromic membranes made of cellulose acetate (CA) for temperature monitoring of sensitive food products. Two dual TC membranes developed for the control of different temperature ranges were formulated using a three‐component system: a leuco‐dye membrane (crystal violet lactone, CVL) integrated with an acidic membrane containing the color developer (salicylic acid) and the acidic solvent with different melting points (decanoic acid, DA, or methacrylic acid, MA). The CVL membrane, together with the DA membrane, showed an irreversible color change when exposed to 35°C, which was facilitated by the melting of DA. The CVL membrane also underwent an irreversible color change when exposed to 15°C together with the MA membrane. The membranes were characterized in detail using scanning electron microscopy. The evaluation of color changes, reproducibility, specificity, and stability ensured the practical suitability of these membranes. Overall, this innovative approach has proven to be a reproducible, sustainable, cost‐effective method to produce irreversible colorimetric temperature sensors. These sensors have significant potential for applications in the food and pharmaceutical industries and offer a promising way to improve product safety and quality. [ABSTRACT FROM AUTHOR]

Pyomelanin, a polymeric pigment in Pseudomonas, arises mainly from alterations in tyrosine degradation. The chemical structure of pyomelanin remains elusive due to its heterogeneous nature. Here, we report strain‐specific differences in pyomelanin structural features across Pseudomonas using PAO1 and PA14 reference strains carrying mutations in hmgA (a gene involved in pyomelanin synthesis), a melanogenic P. aeruginosa clinical isolate (PAM), and a melanogenic P. extremaustralis (PexM). UV spectra showed dual peaks for PAO1 and PA14 mutants and single peaks for PAM and PexM. FTIR phenol : alcohol ratio changes and complex NMR spectra indicated non‐linear polymers. UVC radiation survival increased with pyomelanin addition, correlating with pigment absorption attenuation. P. extremaustralis UVC survival varied with melanin source, with PAO1 pyomelanin being the most protective. These findings delineate structure‐based pyomelanin subgroups, having distinct physiological effects. [ABSTRACT FROM AUTHOR]

Bixin is a naturally occurring fat-soluble diapocarotenoid that has been extracted using various methods. It is used in a variety of food applications, most notably dairy products such as butter, cheese, and margarine, as well as other foods such as meat and confectionaries. However, optimizing process conditions is still required to achieve the maximum pigment yield. The current study examined the impact of solvents such as ethyl acetate, methanol, and ethanol on bixin yield, total phenol content, and hue angle by varying process parameters such as time (10, 20, and 30 min), temperature (50, 60, and 70 °C), and seed-to-solvent ratio (1:5, 1:10, and 1:15). To optimize the process parameters and generate multiple regression models for the responses, the Box–Behnken design was used. At 60 °C and a seed-to-solvent ratio of 1:5, ethyl acetate extract had a maximum bixin content of 2.04 ± 0.28% in 30 min. The methanol extract, on the other hand, had a maximum total phenol content of 5.1 ± 0.19 mg GAE/g in 20 min at 70 °C in a 1:15 ratio. Maximum redness intensity was observed in a 10 min ethyl acetate extract with a hue angle of 20.75° at 50 °C and a seed-to-solvent ratio of 1:10. Methanol was observed to be the optimized solvent for bixin extraction, with higher total phenol content and color. As a result, the optimal conditions were 70 °C, a seed-to-solvent ratio of 1:15, and a treatment time of 30 min. The absolute error percentage of the models was less than 10%, which suggests the model was accurate. [ABSTRACT FROM AUTHOR]

Annatto (Bixa orellana L.), a tropical plant, has a promising place in industrial sector notably in food sector due to increasing consumer demand for complete natural products. The pigments obtained from the seed coat of annatto have the property of imparting colours ranging from red to yellow, and these colours are used as a natural colourant in foods. The major colouring pigments present are bixin and norbixin. Modern extraction methods are required to improve the yield of pigments with less energy consumption. The present work focuses on microwave assisted aqueous extraction of pigments from annatto seeds by varying the seed to water ratio (1:1, 1:2, and 1:3 w/v), temperature (50, 60, and 70 °C), and extraction time (10, 20, and 30 min) at 700 W and it was compared with hot aqueous extraction using Box-Behnken design. The treatment combination during hot aqueous and microwave-assisted extraction having seed to water ratio, temperature, and residence time of 1:1, 50 °C, and 30 min and 1:1, 70 °C, and 30 min showed better yield of 0.237% and 0.625% bixin, and 2.31% and 3.008% of norbixin, respectively. The optimized extraction conditions performed at seed to water ratio of 1:1 at 60 °C for 30 min using microwave-assisted extraction was recommended to provide the maximum yield of bixin and norbixin pigments. [ABSTRACT FROM AUTHOR]

Phaeocystis globosa is an important bloom‐forming marine phytoplankton species that often accumulates to large levels in temperate and tropical waters and has significant impacts on food webs and biogeochemical cycles. It can form "giant" colonies that reach 3 cm in diameter. Microscopic observations, colony elemental composition, and pigment composition were analyzed to assess the characteristics of colonies as a function of colony size. Particulate organic carbon (POC) per unit surface area, colonial cell density, and chlorophyll a per unit surface area all increased with colony size, in contrast to results from temperate waters. Cellular chl a averaged 0.85 pg chl · cell−1. Colonies had both photosynthetic and protective pigments, with fucoxanthin being the dominant accessory pigment. Based on chl a and pigment levels, it appears colonies were acclimated to relatively low irradiances, likely due to their life cycle and the extremely turbulent environment in which they grew. Mucous carbon ranged from 16.2% to 79.2% of the total POC, and mucous carbon per unit surface area increased with colony size, suggesting that the mucous envelope did not thin as the colony grew. Based on elemental composition, nitrogen did not appear to limit growth, but phosphorus:carbon ratios were similar to those of P‐limited cultures. Giant colonies represent an extreme response to the environment, but they do not appear to have greatly different characteristics than other tropical strains. [ABSTRACT FROM AUTHOR]

Over the past few years, there has been an increasing fascination with environmentally conscious techniques for the synthesis of nanoparticles, due to the drawbacks associated with conventional methodologies. These conventional methods frequently depend on the utilization of hazardous chemical substances and yield substantial waste, resulting in detrimental ecological contamination. As a result, alternative strategies utilizing plants and microorganisms such as bacteria, fungi, algae, and their metabolites have gained attention. Microbial pigments (MPs) have gained significant attention in recent years due to their versatile bioactivities. This field of research combines the unique properties of MPs with the diverse applications of metal nanoparticles (MNPs), resulting in a range of promising outcomes. In microbial pigment-mediated nanoparticles (MP-MNPs) synthesis, the biological activities, chemical diversity of pigments, solubility in aqueous medium, lower reaction time, and renewable energy account for high rate of MNPs synthesis with divers shapes and sizes along with corresponding applications. Furthermore, it mitigates the use of harmful chemicals and reduces the generation of waste associated with conventional methods. However, care has to be taken to select suitable MPs for MNPs synthesis, such as in terms of solubility, stability, non-toxicity, and extraction of pigment. This review focuses on the utilization of MPs in the fabrication of MNPs, discussing the possible mechanisms and applications of the synthesized nanoparticles. The advantages and limitations of the microbial pigment-mediated synthesis of different MNPs are also summarized in this review. [ABSTRACT FROM AUTHOR]

Pigments serve a multitude of functions in biology including light harvesting for photosynthesis, radiation protection, membrane support, and defense. The ubiquity of pigments—especially within extremophiles found in high-radiation, high-salinity, and dry environments—and their detectability via mission-ready techniques have elevated these molecules as promising targets in the search for evidence of life elsewhere. Moreover, the detection of pigments has been proposed as a "smoking gun" for extraterrestrial life as it has been suggested that these molecules cannot be generated abiotically. However, while pigments may hold promise as a biosignature, current understanding of their possible prebiotic origins remains understudied and uncertain. Better understanding of the abiotic synthesis of pigments is critical for evaluating the biogenicity of any pigment detected during missions, including by the Mars Perseverance rover or from returned samples. Compounding this uncertainty is the broad definition of pigment as it includes any compound capable of absorbing visible light and by itself does not specify a particular chemical motif. While not experimentally verified, there are promising prebiotic routes for generating pigments including hemes, chlorophylls, and carotenoids. Herein, we review the biochemistry of pigments, the inherent assumptions made when searching for these molecules in the field, their abiotic synthesis in industry and prebiotic reactions, prebiotically relevant molecules that can mimic their spectral signatures, and implications/recommendations for future work. [ABSTRACT FROM AUTHOR]

The construction of full‐color fluorescence systems has received widespread attention because of their applications in lighting materials, optoelectronic materials, and fluorescent probes. However, for the full‐color luminescence system based on trichromatic materials, there are no connections between materials of different luminescent colors. Herein, A new donor‐acceptor dye with red fluorescence was synthesized. The dye displays excellent optical properties of short half‐peak width and strong fluorescence emission. An effective energy transfer process from the dansyl donor to the acceptor was observed with a transfer efficiency of 81 %. Further, dyes with green and blue fluorescence were introduced to construct a full‐spectrum fluorescent system. Through exchange reactions of Diels‐Alder dynamic covalent bonds, red, green, and blue luminescence can be converted. This work provides a new idea for the design of full‐color fluorescent materials. [ABSTRACT FROM AUTHOR]

Bark paintings represent a unique artform that originated in Australia and continues to this day. This paper presents a scientific investigation into both the pigments and binders used by Aboriginal artists from across the Northern Territory (NT) and the Kimberley region in Western Australia (WA) and represents the first major study dedicated to identifying these materials in samples taken from paintings. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), Fourier transform infrared (FTIR) and Raman spectroscopy were used to identify the pigments in the four colors commonly associated with works by Aboriginal artists: red, yellow, black, and white. Iron oxides are used for red and yellow. Typically, kaolin is used for white and carbon or natural manganese ores are used for black, although the use of other pigments such as huntite (white) and battery black were seen in paintings from specific locations. Evidence of trade could not be established during this study; however, analysis shows that artists may use different pigments based on location and availability. A combination of FTIR and pyrolysis-gas chromatography-mass spectrometry (pyrolysis-GC-MS) was utilized to investigate the presence of a binder in the paint. Plant-based materials were identified as the binder in the majority of the paintings. The use of orchid juice was common, both as a preparatory layer on the bark substrate and as a paint binder. The presence of synthetic resins was more widespread than anticipated, attributed to both conservation efforts and more modern painting practices. [ABSTRACT FROM AUTHOR]

Melanins are heterogenous biopolymers produced by many macro and microorganisms. They enhance the ecological fitness of the producer organisms by improving their virulence and protecting them from radiation, osmotic and heat stresses. Fungi synthesise either DOPA or DHN melanin and deposit them on their cell walls. Some fungal isolates produce water soluble melanin (pyomelanin) which is excerted out of the hyphae into the surrounding environment. Pyomelanin, a polymer of homogentisate, exhibits antimicrobial, UV screening, antioxidative, and anti-inflammatory activities and recent studies also show that pyomelanin could find use in space travel as radiation shield. However, scant literature is available on fungi with ability to produce pyomelanin. We report for the first time that Amorosia littoralis occurs as a root endophyte in mangrove species including Avicennia marina , Bruguiera cylindrica and Bruguiera gymnorhiza and produces pyomelanin. Considering the various technological uses of pyomelanin, this study underscores the need to explore fungi of different habitats to identify hyperproducers and to obtain chemically diverse pyomelanin. [ABSTRACT FROM AUTHOR]

Summary: In the storage process, meat is susceptible to external factors that produce corruption and deterioration, affecting consumers' health. Therefore, preparing an indicator membrane that can detect freshness in real time, non‐destructively, and visually is significant. Herein, an indicator membrane was prepared by electrostatic spinning technology using polyvinyl alcohol (PVA) as the substrate and curcumin (CUR) and indigo (IND) as the mixed indicator for freshness detection. When curcumin and indigo were mixed at 3:1 (w/w), CUR was transformed from ketone type to enol type with the gradual increase of pH, and IND underwent electron leaps, which resulted in green, brown, and reddish‐brown colour changes in the solution, and the colour development effect was effectively improved. The characterisation results showed that the average fibre diameter of the PVA/0.8 indicator membrane was 252 nm, the hybrid indicator was successfully loaded in the nanofibres, and the water contact angle was 103.6°, which was hydrophobic. In addition, the indicator membrane was sensitive to trimethylamine (limit of detection 17.38 ppm) and triethylamine (limit of detection 27.77 ppm) but insensitive to saline, ethanol, ethyl acetate, and other contaminants with detection specificity. Finally, the colour of the indicating membrane changes from green to brown during the storage of mutton in the mutton was rotten, indicating that the naked eye can judge the freshness of the mutton. Therefore, the PVA/CUR/IND indicator membrane has excellent potential for application in real‐time and non‐destructive detection of mutton freshness. [ABSTRACT FROM AUTHOR]

Brilliant, diverse colour ornaments of birds were one of the crucial cues that led Darwin to the idea of sexual selection. Although avian colouration plays many functions, including concealment, thermoregulation, or advertisement as a distasteful prey, a quality‐signalling role in sexual selection has attracted most research attention. Sexually selected ornaments are thought to be more susceptible to external stressors than naturally selected traits, and as such, they might be used as a test for environmental quality. For this reason, the last two decades have seen numerous studies on the impact of anthropogenic pollution on the expression of various avian colour traits. Herein, we provide the first meta‐analytical summary of these results and examine whether there is an interaction between the mechanism of colour production (carotenoid‐based, melanin‐based and structural) and the type of anthropogenic factor (categorised as heavy metals, persistent organic pollutants, urbanisation, or other). Following the assumption of heightened condition dependence of ornaments under sexual selection, we also expected the magnitude of effect sizes to be higher in males. The overall effect size was close to significance and negative, supporting a general detrimental impact of anthropogenic pollutants on avian colouration. In contrast to expectations, there was no interaction between pollution types and colour‐producing mechanisms. Yet there were significant differences in sensitivity between colour‐producing mechanisms, with carotenoid‐based colouration being the most affected by anthropogenic environmental disturbances. Moreover, we observed no significant tendency towards heightened sensitivity in males. We identified a publication gap on structural colouration, which, compared to pigment‐based colouration, remains markedly understudied and should thus be prioritised in future research. Finally, we call for the unification of methods used in colour quantification in ecological research to ensure comparability of results among studies. [ABSTRACT FROM AUTHOR]

The article examines the GoPGS gene's role in regulating pigment gland size in cotton plants and its connection to biotic stress tolerance. Researchers discovered that suppressing the GoPGS gene resulted in larger pigment glands and increased resistance to pests and pathogens. They also found that the GoPGS gene is controlled by the GoPGF gene and is involved in the jasmonic acid pathway. These findings offer insights into the development of cotton pigment glands and their role in defending against biotic stress. Manipulating the GoPGS gene's activity may be a potential method for enhancing cotton plants' resistance to biotic stresses. [Extracted from the article]

This paper proposes a method for the short-process recovery and reuse of rare earth secondary resources. Low-value rare earth polishing powder waste (WP), trichromatic phosphor waste (WT), NdFeB permanent magnetic waste (WN), and SmCo permanent magnetic waste (WS) were used as the raw materials. Based on the concept of combinatorial chemistry, energy-efficient cool pigments and environmental remediation materials were synthesized by a solid-phase method. The results showed that the synthesized materials had fluorite-type and garnet-type structures. In terms of cool pigments, doping with different rare earth permanent magnets can enrich the color (including yellow, green, brown, gray, and blue) and cause fluctuations in the near-infrared (NIR) reflectance (59.05–99.54 %) and NIR solar reflectance (55.32–95.64 %). Yellow fluorite-type pigments (WP: WT = 1:1) have the highest NIR reflectance (R = 99.54 %), while brown fluorite-type pigments (WP: WN = 1:0.1) and blue garnet-type pigments (WP:WS = 1:0.1) have relatively high NIR reflectance, 88.18 % and 59.30 %, respectively. The synthesized pigments possessed better chemical stabilities and thermal insulation performance. In terms of environmental remediation materials, the adsorption capacities of fluorite-type materials for F− and PO 4 3− can reach 84.03 mg/g and 85.3 mg/g, respectively. In summary, materials synthesized from rare earth waste exhibit excellent potential for use in energy-efficient wastewater treatment and promote the sustainable utilization of secondary rare earth resources. [ABSTRACT FROM AUTHOR]

Novel pressure field assisted non-hydrolytic sol-gel method is developed for the in-situ synthesis of novel seed-pulp-structured C@ZrSiO 4 pigments. The obtained pigments, which are composed of in-situ carbon derived from leaving organic groups as core and zircon as shell, were characterized via DSC-TG, XRD, FT-IR, Raman, XPS, SEM, TEM, UV–Vis, and automatic colorimeters. It was found that the pressure field promotes the non-hydrolytic sol-gel heterogeneous polycondensation reaction and the direct transformation of reaction groups into in-situ spherical carbon. Meanwhile, the in-situ spherical carbon was enclosed by heterogeneous condensation bonds wrap and formed a dense structure. The as-prepared pigments exhibited excellent color rendering performance (L* = 21.07, a* = 0.48, b* = 0.75) and thermal stability. [ABSTRACT FROM AUTHOR]

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Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chemical investigation of the hydnoid fungus Sarcodontia setosa resulted in the isolation of five compounds, including two new sarcodontic acid derivatives – setosic acid (1) and 7,8-dehydrohomosarcodontic acid (2) along with three known benzoquinone pigments – sarcodontic acid (3), 4,5-dehydrosarcodontic acid (4) and dihydrosarcodontic acid (5). The structures were elucidated using spectroscopic methods (UV, NMR and HR-ESIMS). The biosynthetic relationship of the isolated compounds is proposed and discussed. Antibacterial activity screening of compounds 1–5 against ESKAPE bacterial strains in vitro with zones of inhibition was performed and MIC values were established for the most active compounds (3 and 5). [ABSTRACT FROM AUTHOR]

Co/Mn co-substituted MgAl 2 O 4 pigments were spray pyrolysis, and their crystal structure and optical properties were characterized with changing the Co/Mn ratio and synthesis temperature. Regardless of the Co/Mn ratio, the resulting pigments showed spinel structured MgAl 2 O 4 phase without any impurity phase. The synthesized Mg 0.5 Co 0.5 Al 2 O 4 and Mg 0.5 Mn 0.5 Al 2 O 4 showed a dark blue and brown color due to the visible light absorption by the 4A 2 (F) → 4T 1 (P) transition of Co2+ and the d-d transition of Mn2+, respectively. The black colored pigment was achieved by simultaneous substituting Co2+ and Mn2+ in the Mg2+ tetrahedral site in MgAl 2 O 4. The optical band gap of the Mg 0.5 Co 0.5-x Mn x Al 2 O 4 pigment decreased linearly from 3.08 eV (x = 0) to 2.46 eV (x = 0.4) as the Mn2+ content increased. As a result, Mg 0.5 Co 0.1 Mn 0.4 Al 2 O 4 uniformly absorbed the entire visible light and had a black color (L* = 28.10, C* = 1.68). In terms of obtaining high near-infrared reflectance and good blackness, the optimal calcination temperature of Mg 0.5 Co 0.1 Mn 0.4 Al 2 O 4 was determined to be 900 °C. The optimized Mg 0.5 Co 0.1 Mn 0.4 Al 2 O 4 black pigment had a good LiDAR reflectance (38 % at 905 nm) and excellent chemical stability, and showed improved heat shielding performance compared to carbon black using in black vehicles. [ABSTRACT FROM AUTHOR]

One of the factors precluding potato juice application in the food industry is its propensity for enzymatic browning. The addition of fruit and vegetable concentrates rich in organic acids can reduce unfavorable changes in the color of potato juices and influence the content of biologically active compounds. This study aimed to investigate the effect of the addition of natural fruit and vegetable concentrates to potato juices on their color and on the composition and contents of anthocyanin pigments isolated from them. The color, composition and amount of anthocyanins in potato juices and dyes were determined using HPLC-DAD and UHPLC MS/MS liquid chromatography. It was found that the juices without concentrate addition had, on average, 61% lower total polyphenol content and 63% lower anthocyanin content compared with the juices with added concentrates. The isolated pigments contained, on average, 30–40 times more anthocyanins compared with those isolated from the non-purified juices. Furthermore, the addition of concentrates enabled ca. 3–5 times more effective isolation of anthocyanins compared with the samples without these additives. Potato juices and dyes with the addition of concentrates showed a lighter color that did not change over time, compared with samples without concentrates. [ABSTRACT FROM AUTHOR]

Chlorella sorokiniana, isolated from a pond adjacent to a cement plant, was cultured using flue gas collected directly from kiln emissions using 20 L and 25000 L photobioreactors. Lipids, proteins, and polysaccharides were analyzed to understand their overall composition for potential applications. The lipid content ranged from 17.97% to 21.54% of the dry biomass, with carotenoid concentrations between 8.4 and 9.2 mg/g. Lutein accounted for 55% of the total carotenoids. LC/MS analysis led to the identification of 71 intact triacylglycerols, 8 lysophosphatidylcholines, 10 phosphatidylcholines, 9 monogalactosyldiacylglycerols, 12 digalactosyldiacylglycerols, and 1 sulfoquinovosyl diacylglycerol. Palmitic acid, oleic acid, linoleic acid, and α-linolenic acid were the main fatty acids. Polyunsaturated fatty acid covers ≥ 56% of total fatty acids. Protein isolates and polysaccharides were also extracted. Protein purity was determined to be ≥75% by amino acid analysis, with all essential amino acids present. Monomer analysis of polysaccharides suggested that they are composed of mainly D-(+)-mannose, D-(+)-galactose, and D-(+)-glucose. The results demonstrate that there is no adverse effect on the metabolite profile of C. sorokiniana biomass cultured using flue gas as the primary carbon source, revealing the possibility of utilizing such algal biomass in industrial applications such as animal feed, sources of cosmeceuticals, and as biofuel. [ABSTRACT FROM AUTHOR]

In situ measurements of particulate inherent optical properties (IOPs) – absorption (ap(λ)), scattering (bp(λ)), and beam attenuation (cp(λ)) – are crucial for development of optical algorithms that retrieve biogeochemical quantities such as Chlorophyll a , particulate organic carbon (POC) and total suspended matter (TSM). Here we present a compilation of particulate absorption-attenuation spectrophotometric data measured underway on nine Atlantic Meridional Transect (AMT) cruises between 50° north to 50° south from 2009–2019. The compilation includes co-incident high performance liquid chromatography (HPLC) phytoplankton pigment concentrations, which are used to calibrate transects of Total Chlorophyll a (Tot_Chl_a) concentrations derived from the ap(λ) line-height method. The IOP data are processed using a consistent methodology, and include propagated uncertainties for each IOP variable, uncertainty quantification for the Tot_Chl_a concentrations based on HPLC match-ups, application of consistent set of quality-control filters, and standardisation of output data fields and formats. The total IOP dataset consists of ~310,000 measurements at a 1 minute binning (~270,000 hyper-spectral) and > 700 co-incident HPLC pigment surface samples (~600 of which are coincident with hyper-spectral IOPs). We present geographic variation in the IOPs, HPLC phytoplankton pigments, and the ap -derived Tot_Chl_a concentrations, which are shown to have uncertainties between 8–20 %. Additionally, to stimulate further investigation of accessory pigment extraction from ap(λ) , we quantify pigment correlation matrices and identify spectral characteristics of end-member ap(λ) spectra where accessory pigment groupings are present in higher concentrations relative to Tot_Chl_a. All data are made publicly available in SeaBASS and NetCDF formats via the following links: https://seabass.gsfc.nasa.gov/archive/PML/AMT , and https://doi.org/10.5281/zenodo.12527954. [ABSTRACT FROM AUTHOR]

Summary: In the early 1900s, Erwin Baur established Antirrhinum majus as a model system, identifying and characterising numerous flower colour variants. This included Picturatum/Eluta, which restricts the accumulation of magenta anthocyanin pigments, forming bullseye markings on the flower face.We identified the gene underlying the Eluta locus by transposon‐tagging, using an Antirrhinum line that spontaneously lost the nonsuppressive el phenotype. A candidate MYB repressor gene at this locus contained a CACTA transposable element. We subsequently identified plants where this element excised, reverting to a suppressive Eluta phenotype. El alleles inhibit expression of anthocyanin biosynthetic genes, confirming it to be a regulatory locus. The modes of action of Eluta were investigated by generating stable transgenic tobacco lines, biolistic transformation of Antirrhinum petals and promoter activation/repression assays.Eluta competes with MYB activators for promoter cis‐elements, and also by titrating essential cofactors (bHLH proteins) to reduce transcription of target genes. Eluta restricts the pigmentation established by the R2R3‐MYB factors, Rosea and Venosa, with the greatest repression on those parts of the petals where Eluta is most highly expressed.Baur questioned the origin of heredity units determining flower colour variation in cultivated A. majus. Our findings support introgression from wild species into cultivated varieties. [ABSTRACT FROM AUTHOR]

An X-ray fluorescence handheld spectrometer (hh-XRF) is adapted for real-time qualitative and quantitative elemental analysis in scanning mode for applications in cultural heritage. Specifically, the Tracer-5i (Bruker) is coupled with a low-cost constructed computer-controlled x–y target stage that enables the remote control of the target's movement under the ionizing X-ray beam. Open-source software synchronizes the spectrometer's measuring functions and handles data acquisition and data analysis. The spectrometer's analytical capabilities, such as sensitivity, energy resolution, beam spot size, and characteristic transition intensity as a function of the distance between the spectrometer and the target, are evaluated. The XRF scanner's potential in real-time imaging, object classification, and quantitative analysis in cultural heritage-related applications is explored and the imaging capabilities are tested by scanning a 19th-century religious icon. The elemental maps provide information on used pigments and reveal an underlying icon. The scanner's capability to classify metallic objects was verified by analyzing the measured raw spectra of a coin collection using Principal Components Analysis. Finally, the handheld's capability to perform quantitative analysis in scanning mode is demonstrated in the case of precious metals, applying a pre-installed quantification routine. [ABSTRACT FROM AUTHOR]

This article reports on the discovery of pararealgar and semi-amorphous pararealgar in Rembrandt's masterpiece The Night Watch. A large-scale research project named Operation Night Watch was started in 2019. A variety of non-invasive analytical imaging techniques, together with paint sample research, has provided new information about Rembrandt's pigments, materials, and techniques as well as the current condition of the painting. Macroscopic X-ray fluorescence, macroscopic X-ray powder diffraction and reflectance imaging spectroscopy identified the presence of arsenic sulfide pigments and degradation products of these pigments in the doublet sleeves and embroidered buff coat worn by Lieutenant Willem van Ruytenburch (central figure to the right of Captain Frans Banninck Cocq). Examination by light microscopy of two paint samples taken from this area shows a mixture of large sharp-edged tabular yellow and orange to red pigment particles, and scanning electron microscopy-energy dispersive X-ray analysis identified these particles as containing arsenic and sulfur. Using micro-Raman spectroscopy, the yellow particles were identified as pararealgar, and the orange to red particles as semi-amorphous pararealgar. Synchrotron-based X-ray diffraction allowed visualization of the presence of multiple degradation products associated with arsenic sulfides throughout the paint layer. The discovery of pararealgar and semi-amorphous pararealgar is a new addition to Rembrandt's pigment palette. To contextualize our findings and to hypothesize why, how, and where Rembrandt obtained the pigments, we studied related historical sources. A comprehensive review of historical sources gives insight into the types of artificial arsenic sulfides that were available and suggests that a broader range of arsenic pigments could have been available in Amsterdam in the seventeenth century than previously thought. This is supported by the use of a very similar mixture of pigments by Willem Kalf (1619–1693), a contemporary artist based in Amsterdam. Together with the condition of the particles in the paint cross sections, this brings us to the conclusion that Rembrandt intentionally used pararealgar and semi-amorphous pararealgar, together with lead–tin yellow and vermilion, to create an orange paint. [ABSTRACT FROM AUTHOR]

In 1949, Almada Negreiros painted at the maritime station of Rocha do Conde de Óbidos, in Lisbon, six monumental mural paintings, which are considered as his highest artistic achievement. On these paintings, he resorted to a bright colourful palette, which needs to be studied to support conservation and preservation of these artworks for future generations. Among the pigments under study within project ALMADA, the identification of the green samples is the most challenging, as Almada Negreiros seems to have explored different hues by using simultaneously inorganic (e.g., emerald green, Scheele's green and viridian) as well as organo‐synthetic pigments that were rather unusual when employing a traditional mural painting technique (e.g., PG7 and PG8). Moreover, he seems to have admixed white (e.g., titanium white) or blue pigments (e.g., ultramarine) to modify the hues. The different colourants found, as well as the use of mixtures of pigments, hints that Almada Negreiros was keen on experimenting and applying relatively novel painting materials. Raman spectroscopy, given its ability to identify inorganic as well as organic components, is a key analytical tool to discriminate between all these compounds. The findings were also supported by complimentary analytical techniques, including colourimetry, handheld X‐ray fluorescence spectroscopy (h‐XRF) and micro‐Fourier‐transform infrared spectroscopy (μ‐FT‐IR). Identification of the green pigments by Raman spectroscopy is, however, not always straightforward, and it is demonstrated how changes in relative band intensities and band broadening can point to mixtures, where the Raman spectral features of some compounds can easily be overseen in the spectrum. [ABSTRACT FROM AUTHOR]

In this review, topic modeling—an unsupervised machine learning tool—is employed to analyze research on pigments in cultural heritage published from 1999–2023. The review answers the following question: What are topics and time trends in the past three decades in the analytical study of pigments within cultural heritage (CH) assets? In total, 932 articles are reviewed, ten topics are identified and time trends in the share of these topics are revealed. Each topic is discussed in-depth to elucidate the community, purpose and tools involved in the topic. The time trend analysis shows that dominant topics over time include T1 (the spectroscopic and microscopic study of the stratigraphy of painted CH assets) and T5 (X-ray based techniques for CH, conservation science and archaeometry). However, both topics have experienced a decrease in attention in favor of other topics that more than doubled their topic share, enabled by new technologies and methods for imaging spectroscopy and imaging processing. These topics include T6 (spectral imaging techniques for chemical mapping of painting surfaces) and T10 (the technical study of the pigments and painting methods of historical and contemporary artists). Implications for the field are discussed in conclusion. [ABSTRACT FROM AUTHOR]

Most Fusarium species are known as endophytes and/or phytopathogens of higher plants and have a worldwide distribution. Recently, information discovered with molecular tools has been also published about the presence of these fungi in the microbiome of truffle fruiting bodies. In the present work, we isolated and identified three Fusarium strains from truffle fruiting bodies. All isolates were assigned to the same species, F. commune, and the strains were deposited in the All-Russian Collection of Microorganisms under accession numbers VKM F-5020, VKM F-5021, and VKM F-5022. To check the possible effects of the isolated strains on the plants, the isolates were used to infect sterile seedlings of Sarepta mustard (Brassica juncea L.). This model infection led to a moderate suppression of the photosynthetic apparatus activity and plant growth. Here, we present characteristics of the F. commune isolates: description of the conidial morphology, pigmentation, and composition of the mycelium fatty acids. Overall, this is the first description of the Fusarium cultures isolated from truffle fruiting bodies. Possible symbiosis of the F. commune strains with truffles and their involvement in the cooperative fatty acid production are proposed. [ABSTRACT FROM AUTHOR]

Due to widespread selenium deficiency in food the aim of this study was to evaluate the effectiveness of a new Se(II)-containing organic chemical compound 2-iminoselenazolidin-4-ones (ISeA) in the form of a nanoscale associate (1–5 nm) solution for Swiss chard and komatsuna plants biofortification. Application of the chosen substance as a foliar treatment (2 mg·L−1) and as an additive to a hydroponic nutrient solution (10 mg·L−1) was performed. Both cultures had a high level of Se absorption, distribution and accumulation in leaves two or more times greater than in petioles. Se content in chard petioles (15 mg·L−1) when applying ISeA as a component of the nutrient solution exceeded the accumulation of Se during foliar treatment (9.6 mg·L−1) and the same trend in the komatsuna leaves was observed. When applying ISeA to the nutrient solution, an increase in komatsuna and chard biomass was seen at 36 and 68% and for leaf treatment by 21 and 45%, respectively. For komatsuna and chard an increase in the ratio of dry to fresh weight was also observed to be 27 and 26%, and for foliar treatment—0 and 16 % , respectively. Treatments led to increase in chard plants height (7–17%), enlargement of leaves (19–42%), a rise in photosynthetic pigments (20–60%) and anthocyanin (2.9 and 2.2 times) concentration, and for komatsuna—the multiplication of leaves number ( 28 % ) and their surface area (27–29%) as well as a rise in the concentration of anthocyanin (1.0 and 1.6 times) with foliar treatment and nutrient solution enrichment. [ABSTRACT FROM AUTHOR]

Flavonoids are polyphenolic plant constituents. Anthocyanins are flavonoid pigments found in higher plants that show a wide variety of colors ranging from red through purple to blue. The blue color of the flowers is mostly attributed to anthocyanins. However, only a few types of anthocyanidin, chromophore of anthocyanin, exist in nature, and the extracted pigments are unstable with the color fading away. Therefore, the wide range and stable nature of colors in flowers have remained a mystery for more than a century. The mechanism underlying anthocyanin-induced flower coloration was studied using an interdisciplinary method involving chemistry and biology. Furthermore, the chemical studies on flavonoid pigments in various edible plants, synthetic and biosynthetic studies on anthocyanins were conducted. The results of these studies have been outlined in this review. [ABSTRACT FROM AUTHOR]

To assess the efficacy of treatment on acute posterior multifocal placoid pigment epitheliopathy (APMPPE) and relentless placoid chorioretinopathy (RPC). Cases were identified from three UK uveitis centers. Retrospective analysis of visual acuity recovery; OCT structural outcomes; and retinal lesion quantification in observed and treated cases of APMPPE/RPC. There were nine APMPPE and three RPC cases. Out of 12 patients, six were female. Median age: 26.5 years (range, 20–57 years). Four cases (six eyes) were observed, and eight cases (15 eyes) received corticosteroids ± immunosuppression. 4/4 observed and 6/10 treated foveal involving eyes regained 0.00 LogMAR vision. Observed lesions achieved more favorable anatomical outcomes. New lesions post-presentation developed in 1/6 (16%) observed eye versus 10/15 (66%) treated eyes. In three cases, a delayed, rebound lesion occurrence was observed post-high-dose corticosteroids. While subject to potential treatment bias, in this small case series, natural history alone appears non-inferior to corticosteroid treatment. [ABSTRACT FROM AUTHOR]

This research is concerned with the spectroscopic analysis of red and brown to black pigments used for decoration on 22 fragments of Early Neolithic pottery from settlements located in today's Western Bulgaria. Two complementary analytical techniques are applied – Laser Induced Breakdown Spectroscopy (LIBS) and Fourier Transformed Infrared spectroscopy (FTIR). A multivariate statistical method Principal Component Analysis (PCA) was applied to the obtained LIBS spectral data in order to classify the objects according to the elemental composition of the decorations. The results from LIBS and PCA collaboration show that the investigated sherds are separated mainly in two groups – iron-enriched and manganese-enriched. To complement the results from LIBS measurement and identify the minerals in pigments, an FTIR was applied. The FTIR results of the red decorations revealed the presence of the iron-based mineral hematite, while the brown to black pigments were based on iron-bearing minerals such as hematite, magnetite, and maghemite. Additionally, in some of the samples, a mixture of iron and manganese oxides was detected suggesting the use of ferromanganese ores as a raw material. [ABSTRACT FROM AUTHOR]

The current trend of shifting to food naturalness has prompted food industries to switch from synthetic to natural colorants. Concurrently, there is a spike in interest concerning the extraction of pigments from natural sources using non-conventional extraction techniques as the latter are environmental-friendly and sustainable compared to traditional methods. Microwave-assisted extraction (MAE) is one of the emerging technologies that has been reported to be effective in the recovery of bioactive compounds from a plethora of natural sources because of its ability to expeditiously heat the extraction matrix, leading to rapid product recovery. This review focuses on the voluminous demand for natural colorants, their limitations, and potential food applications. Also, this review emphasizes the underlying principle and mechanism of MAE, as well as studies that unveil the efficacy and suitability of the technique for the recovery of pigments. Hence, given that natural pigments are susceptible to natural degradation, MAE is a promising technology for enhanced pigment yield and stability. In addition, recent trends such as technology integration and novel extraction solvents have considerably widened the scope and versatility of MAE as a greener extraction method. Furthermore, when coupled with MAE, waste valorization and further exploration of novel pigment sources (such as algae and other microorganisms) present thrust areas of research concerning the global sustainable development goals (SDGs). [ABSTRACT FROM AUTHOR]

Purpose: This study aims to perform the surface treatment of synthetic α-Fe2O3 red iron oxide pigment with hydrolysate 3-aminopropyl silane (A) and colloidal silica (CS) and investigate the effects of surface-treated pigment on the styrene acrylic (SA) emulsion and polyurethane (PU) dispersion. Design/methodology/approach: For this purpose, firstly red iron oxide particles were modified with A and CS separately in an aqueous medium. After isolation of the modified iron oxide were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Moreover, the degree of the dispersion stability of the modified pigment in coatings with SA emulsion and PU dispersion was investigated by using an oscillation rheometer. Loss (G''), storage (G') modulus, loss factor [tan(δ)] and yield stress (τ0) values were determined by performing amplitude and frequency sweep tests. Findings: The τ0 in SA coatings decreases with the amount of used A and increases with the amount of used CS. The τ0 decreases as the amount of used A and CS in PU coatings increases. The use of CS on red iron oxide pigments causes storage modulus to increase in SA coatings at low angular frequencies, while it causes a decrease in PU coatings. Originality/value: To the best of the authors' knowledge, for the first time, the suspended state of the iron oxide hybrid pigment formed with CS in the coating was investigated rheologically in this study. [ABSTRACT FROM AUTHOR]

A fluorine-free route has been developed to fabricate V/Pr co-doped zircon (ZrSiO 4) ceramic pigments with Na 3 VO 4 and Pr(NO 3) 3 ·6H 2 O as colourants. The as-prepared pigments were characterized by XRD, Raman, XPS, UV–vis, FE-SEM, TEM and automatic colourimeters. The results show that Na 3 VO 4 can not only act as colourant to produce blue hue, but as mineralizer to accelerate the formation of V/Pr co-doped ZrSiO 4 pigment. A colour tuning between blue, green and yellow can be achieved by increasing the mole ratio of Pr/V, and the most intense yellow hue (L* = 74.55, a* = −0.38, b* = 46.82) is obtained at a mole ratio of Pr/V = 0.5. Both Pr4+ and Pr3+ cations are co-existed in the pigments, where Pr4+ contributes to the generation of yellow hue while Pr3+ undermines the yellow hue. The good chromatic ability in glaze at high temperature suggest its potential application in ceramic decoration. [ABSTRACT FROM AUTHOR]

Despite their overlooked status, weeds are increasingly recognized for their therapeutic value, aligning with historical reliance on plants for medicine and nutrition. This study investigates the medicinal potential of native weed species in Bangladesh, specifically pigments, antioxidants, and free radical scavenging abilities. Twenty different medicinal weed species were collected from the vicinity of Khulna Agricultural University and processed in the Crop Botany Department Laboratory. Pigment levels were determined using spectrophotometer analysis, and phenolics, flavonoids, and DPPH were quantified accordingly. Chlorophyll levels in leaves ranged from 216.70 ± 9.41 to 371.14 ± 28.67 µg g−1 FW, and in stems from 51.98 ± 3.21 to 315.89 ± 17.19 µg g−1 FW. Flavonoid content also varied widely, from 1,624.62 ± 102.03 to 410.00 ± 115.58 mg CE 100 g−1 FW in leaves, and from 653.08 ± 32.42 to 80.00 ± 18.86 mg CE 100 g−1 FW in stems. In case of phenolics content Euphorbia hirta L. displaying the highest total phenolic content in leaves (1,722.33 ± 417.89 mg GAE 100 g−1 FW) and Ruellia tuberosa L. in stems (977.70 ± 145.58 mg GAE 100 g−1 FW). The lowest DPPH 2.505 ± 1.028 mg mL−1was found in Heliotropium indicum L. leaves. Hierarchical clustering links species with pigment, phenolic/flavonoid content, and antioxidant activity. PCA, involving 20 species and seven traits, explained 70.07% variability, with significant PC1 (14.82%) and PC2 (55.25%). Leaves were shown to be superior, and high-performing plants such as E. hirta and H. indicum stood out for their chemical composition and antioxidant activity. Thus, this research emphasizes the value of efficient selection while concentrating on the therapeutic potential of native weed species. [ABSTRACT FROM AUTHOR]

Naturally sourced pH‐sensitive indicator films are of interest for real‐time monitoring of food freshness through color changes because of their safety. Therefore, natural pigments for indicator films are required. However, pigment stability is affected by environmental factors, which can in turn affect the sensitivity and color stability of the pH‐sensitive indicator film. First, natural pigments (anthocyanin, betalain, curcumin, alizarin, and shikonin) commonly used in pH‐sensitive indicator films are presented. Subsequently, the mechanisms behind the change in pigment color under different pH environments and their applications in monitoring food freshness are also described. Third, influence factors, such as the sources, types, and pH sensitivity of pigments, as well as environmental parameters (light, temperature, humidity, and oxygen) of sensitivity and color stability, are analyzed. Finally, methods for improving the pH‐sensitive indicator film are explored, encapsulation of natural pigments, incorporation of a hydrophobic film‐forming matrix or function material, and protective layer have been shown to enhance the color stability of indicator films, the addition of copigments or mental ions, blending of different natural pigments, and the utilization of electrospinning have been proved to increase the color sensitivity of indicator films. This review could provide theoretical support for the development of naturally sourced pH‐sensitive indicator films with high stability and sensitivity and facilitate the development in the field of monitoring food freshness. [ABSTRACT FROM AUTHOR]

Shade matching of extraoral prostheses is completed by mixing pigments and rayon flocking into medical‐grade silicone and using a carrier to evaluate the color match. This process does not account for how material thickness affects the appearance of the silicone. This clinical case report discusses an innovative way to match the patient's skin tone using a digitally designed gradated silicone carrier and how this device allows for the assessment of shade from the thin marginal edge to 5 mm thickness. [ABSTRACT FROM AUTHOR]

In controlled environment agriculture, customized light treatments using lightemitting diodes are crucial to improving crop yield and quality. Red (R; 600-700 nm) and blue light (B; 400-500 nm) are two major parts of photosynthetically active radiation (PAR), often preferred in crop production. Far-red radiation (FR; 700-800 nm), although not part of PAR, can also affect photosynthesis and can have profound effects on a range of morphological and physiological processes. However, interactions between different red and blue light ratios (R:B) and FR on promoting yield and nutritionally relevant compounds in crops remain unknown. Here, lettuce was grown at 200 µmol m-2 s-1 PAR under three different R:B ratios: R:B87.5:12.5 (12.5% blue), R:B75:25 (25% blue), and R:B60:40 (40% blue) without FR. Each treatment was also performed with supplementary FR (50 µmol m-2 s-1; R:B87.5:12.5+FR, R:B75:25+FR, and R:B60:40+FR).White light with andwithout FR (Wand W+FR) were used as control treatments comprising of 72.5% red, 19% green, and 8.5% blue light. Decreasing the R:B ratio from R:B87.5:12.5 to R:B60:40, there was a decrease in fresh weight (20%) and carbohydrate concentration (48% reduction in both sugars and starch), whereas pigment concentrations (anthocyanins, chlorophyll, and carotenoids), phenolic compounds, and various minerals all increased. These results contrasted the effects of FR supplementation in the growth spectra; when supplementing FR to different R:B backgrounds, we found a significant increase in plant fresh weight, dry weight, total soluble sugars, and starch. Additionally, FR decreased concentrations of anthocyanins, phenolic compounds, and various minerals. Although blue light and FR effects appear to directly contrast, blue and FR light did not have interactive effects together when considering plant growth, morphology, and nutritional content. Therefore, the individual benefits of increased blue light fraction and supplementary FR radiation can be combined and used cooperatively to produce crops of desired quality: adding FR increases growth and carbohydrate concentration while increasing the blue fraction increases nutritional value. [ABSTRACT FROM AUTHOR]

The study applies both a minimal and an extended approach for a comprehensive picture of chemical components in wall paintings, including evidence of degradation. Pigments and ligands were characterized via a multi-methodological investigation, including optical microscopy, scanning electron microscopy, Raman micro-spectroscopy, GC-MS, and LC-MS/MS. Particularly, the procedure was tested on wall paintings recently excavated from a Roman domus in Santa Maria Capua Vetere. The hypothesis of a very wealthy owner is supported by the evidence of a multi-layer preparation, a rich variety of pigments, and organic ligands (both terpenic resins and animal glue). The absence of calcite in the pictorial layer (via optical and Raman microscopy) and the presence of organic binders (via GC-MS and LC-MS/MS) clearly indicates the a secco technique.

Juan Martínez Montañés was one of the most important sculptors and altarpiece architects of the Spanish Golden Age. The restoration of the Santa Clara church in Seville has presented a unique opportunity to study the main altarpiece, crafted by Montañés between 1621 and 1623. He was also in charge of the polychromy and gilding, believing that delegating these procedures to others would diminish the quality of his work. This conviction led to a well-known lawsuit with the renowned contemporary Spanish painter Francisco Pacheco. Ultimately, the painter and sculptor Baltasar Quintero performed the polychromy of this altarpiece, but under the strict conditions of Montañés. Various non-invasive analytical techniques, such as CT, UVF, XRF, and digital microscopy, were employed to study wood treatment and polychromy. Additionally, three samples were prepared as cross-sections and analysed by SEM-EDX. The results revealed Montañés’ meticulous woodwork, anticipating its long-term preservation. Consistent with Montañés’ commitment to maintaining the superior quality of his work, the analysis showed an absence of a ground layer in the flesh areas, while the gilding was executed with high-quality gold. The pigment palette corresponds to the treaties and documents of his time, and the extensive areas of later retouches were accurately located. These new data provide a deeper understanding of both the technique and the high standards of one of the most important and globally recognised sculptors.

In this review, topic modeling—an unsupervised machine learning tool—is employed to analyze research on pigments in cultural heritage published from 1999–2023. The review answers the following question: What are topics and time trends in the past three decades in the analytical study of pigments within cultural heritage (CH) assets? In total, 932 articles are reviewed, ten topics are identified and time trends in the share of these topics are revealed. Each topic is discussed in-depth to elucidate the community, purpose and tools involved in the topic. The time trend analysis shows that dominant topics over time include T1 (the spectroscopic and microscopic study of the stratigraphy of painted CH assets) and T5 (X-ray based techniques for CH, conservation science and archaeometry). However, both topics have experienced a decrease in attention in favor of other topics that more than doubled their topic share, enabled by new technologies and methods for imaging spectroscopy and imaging processing. These topics include T6 (spectral imaging techniques for chemical mapping of painting surfaces) and T10 (the technical study of the pigments and painting methods of historical and contemporary artists). Implications for the field are discussed in conclusion.