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18 pages, 674 KiB  
Article
Oil Extraction Systems Influence the Techno-Functional and Nutritional Properties of Pistachio Processing By-Products
by Rito J. Mendoza-Pérez, Elena Álvarez-Olmedo, Ainhoa Vicente, Felicidad Ronda and Pedro A. Caballero
Foods 2025, 14(15), 2722; https://doi.org/10.3390/foods14152722 - 4 Aug 2025
Viewed by 186
Abstract
Low-commercial-value natural pistachios (broken, closed, or immature) can be revalorised through oil extraction, obtaining a high-quality oil and partially defatted flour as by-product. This study evaluated the techno-functional and nutritional properties of the flours obtained by hydraulic press (HP) and single-screw press (SSP) [...] Read more.
Low-commercial-value natural pistachios (broken, closed, or immature) can be revalorised through oil extraction, obtaining a high-quality oil and partially defatted flour as by-product. This study evaluated the techno-functional and nutritional properties of the flours obtained by hydraulic press (HP) and single-screw press (SSP) systems, combined with pretreatment at 25 °C and 60 °C. The extraction method significantly influenced flour’s characteristics, underscoring the need to tailor processing conditions to the specific technological requirements of each food application. HP-derived flours presented lighter colour, greater tocopherol content, and higher water absorption capacity (up to 2.75 g/g), suggesting preservation of hydrophilic proteins. SSP-derived flours showed higher concentration of protein (44 g/100 g), fibre (12 g/100 g), and minerals, and improved emulsifying properties, enhancing their suitability for emulsified products. Pretreatment at 25 °C enhanced functional properties such as swelling power (~7.0 g/g) and water absorption index (~5.7 g/g). The SSP system achieved the highest oil extraction yield, with no significant effect of pretreatment temperature. The oils extracted showed high levels of unsaturated fatty acids, particularly oleic acid (~48% of ω-9), highlighting their nutritional and industrial value. The findings support the valorisation of pistachio oil extraction by-products as functional food ingredients, offering a promising strategy for reducing food waste and promoting circular economy approaches in the agri-food sector. Full article
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22 pages, 6617 KiB  
Article
Natural Plant Oils as Anti-Algae Biocides for Sustainable Application in Cultural Heritage Protection
by Michał Komar, Nathnael Derese, Kamil Szymczak, Paulina Nowicka-Krawczyk and Beata Gutarowska
Sustainability 2025, 17(15), 6996; https://doi.org/10.3390/su17156996 - 1 Aug 2025
Viewed by 267
Abstract
The prevention of biofilm formation and algal biodeterioration on building materials, particularly on cultural heritage sites, is a growing concern. Due to regulatory restrictions on conventional algicidal biocides in Europe, natural alternatives such as essential oils are gaining interest for their potential use [...] Read more.
The prevention of biofilm formation and algal biodeterioration on building materials, particularly on cultural heritage sites, is a growing concern. Due to regulatory restrictions on conventional algicidal biocides in Europe, natural alternatives such as essential oils are gaining interest for their potential use in heritage conservation. This study evaluates the anti-algal activity of Salvia officinalis and Equisetum arvense (essential oils, hydrolates, and extracts) against a mixed culture of five green algae species (Bracteacoccus minor, Stichococcus bacillaris, Klebsormidium nitens, Chloroidium saccharophilum, and Diplosphaera chodatii). The plant materials were processed using hydrodistillation and solvent extraction, followed by chemical characterization through gas chromatography–mass spectrometry (GC-MS). Biological efficacy was assessed by measuring algal growth inhibition, changes in biomass colour, chlorophyll a concentration, and fluorescence. S. officinalis yielded higher extract quantities (extraction yield: 23%) than E. arvense and contained bioactive compounds such as thujone, camphor, and cineole, which correlated with its strong anti-algal effects. The essential oil of S. officinalis demonstrated the highest efficacy, significantly inhibiting biofilm formation (zones of inhibition: 15–94 mm) and photosynthetic activity at 0.5% concentration (reduction in chlorophyll a concentration 90–100%), without causing visible discolouration of treated surfaces (∆E < 2). These findings highlight the potential of S. officinalis essential oil as a natural, effective, and material-safe algicidal biocide for the sustainable protection of cultural heritage sites. Full article
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18 pages, 1332 KiB  
Article
Optimization of Anthocyanin Extraction from Purple Sweet Potato Peel (Ipomea batata) Using Sonotrode Ultrasound-Assisted Extraction
by Raquel Lucas-González, Mirian Pateiro, Rubén Domínguez-Valencia, Celia Carrillo and José M. Lorenzo
Foods 2025, 14(15), 2686; https://doi.org/10.3390/foods14152686 - 30 Jul 2025
Viewed by 275
Abstract
Sweet potato is a valuable root due to its nutritional benefits, health-promoting properties, and technological applications. The peel, often discarded during food processing, can be employed in the food industry, supporting a circular economy. Purple sweet potato peel (PSPP) is rich in anthocyanins, [...] Read more.
Sweet potato is a valuable root due to its nutritional benefits, health-promoting properties, and technological applications. The peel, often discarded during food processing, can be employed in the food industry, supporting a circular economy. Purple sweet potato peel (PSPP) is rich in anthocyanins, which can be used as natural colourants and antioxidants. Optimising their extraction can enhance yield and reduce costs. The current work aimed to optimize anthocyanin and antioxidant recovery from PSPP using a Box-Behnken design and sonotrode ultrasound-assisted extraction (sonotrode-UAE). Three independent variables were analysed: extraction time (2–6 min), ethanol concentration (35–85%), and liquid-to-solid ratio (10–30 mL/g). The dependent variables included total monomeric anthocyanin content (TMAC), individual anthocyanins, and antioxidant activity. TMAC in 15 extracts ranged from 0.16 to 2.66 mg/g PSPP. Peonidin-3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside was the predominant anthocyanin. Among four antioxidant assays, Ferric-reducing antioxidant power (FRAP) showed the highest value. Ethanol concentration significantly influenced anthocyanin and antioxidant recovery (p < 0.05). The model demonstrated adequacy based on the coefficient of determination and variation. Optimal extraction conditions were 6 min with 60% ethanol at a 30 mL/g ratio. Predicted values were validated experimentally (coefficient of variation <10%). In conclusion, PSPP is a promising matrix for obtaining anthocyanin-rich extracts with antioxidant activity, offering potential applications in the food industry. Full article
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18 pages, 549 KiB  
Article
Extension of Poultry Meat Shelf Life Using Cynara cardunculus L. Leaf Extracts as a Natural Preservative
by Cássia H. Barbosa, Mariana A. Andrade, Fernanda Vilarinho, Ana Sanches Silva and Ana Luísa Fernando
Foods 2025, 14(15), 2592; https://doi.org/10.3390/foods14152592 - 24 Jul 2025
Viewed by 293
Abstract
Food additives are used to prevent food spoilage and extend its shelf life. However, concerns regarding the potential health implications associated with some synthetic additives have prompted research efforts aimed at identifying natural alternatives, such as plant extracts. Cynara cardunculus L. (cardoon) is [...] Read more.
Food additives are used to prevent food spoilage and extend its shelf life. However, concerns regarding the potential health implications associated with some synthetic additives have prompted research efforts aimed at identifying natural alternatives, such as plant extracts. Cynara cardunculus L. (cardoon) is known for its antimicrobial and antioxidant properties. The aim of this study was to evaluate the capability of ethanolic food-grade extracts from cultivated cardoon and globe artichoke leaves to preserve poultry breast meat during refrigerated storage. A total of seven treatment groups were tested: one control group (no extract) and six active groups with 0.5%, 1%, and 2% (w/w) of either cultivated cardoon or globe artichoke leaf extracts. Lipid oxidation, moisture, colour, pH, acidity, and microbial growth were assessed in poultry meat samples over 15 days. Both extracts were effective in extending shelf life, up to 11 days, by delaying lipid oxidation and microbial growth. Cardoon extract (1% w/w) displayed superior antimicrobial efficacy, maintaining microbial counts below 5 Log CFU/g meat until day 15, compared to the control. Cultivated cardoon leaf extract proves promising as a natural antimicrobial and antioxidant, extending the shelf life of poultry meat. This presents an opportunity to maintain the quality of meat products, aligning with consumer preferences for natural ingredients and sustainable practices. Full article
(This article belongs to the Special Issue Preservation and Shelf Life Extension of Food Products)
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25 pages, 1919 KiB  
Article
Valorisation of Beetroot Peel for the Development of Nutrient-Enriched Dehydrated Apple Snacks
by Ioana Buțerchi, Liliana Ciurlă, Iuliana-Maria Enache, Antoanela Patraș, Gabriel-Ciprian Teliban and Liviu-Mihai Irimia
Foods 2025, 14(15), 2560; https://doi.org/10.3390/foods14152560 - 22 Jul 2025
Viewed by 388
Abstract
Beetroot peel, an underutilised by-product of the food industry, has significant potential for valorisation due to its high content of bioactive compounds and natural pigments. This study aimed to sustainably reintroduce beetroot peel into the food chain by enriching the nutritional value of [...] Read more.
Beetroot peel, an underutilised by-product of the food industry, has significant potential for valorisation due to its high content of bioactive compounds and natural pigments. This study aimed to sustainably reintroduce beetroot peel into the food chain by enriching the nutritional value of dehydrated apple snacks. Five experimental formulations of apple slices were developed: dipped in 5% RBPP in water, dipped in 10% RBPP in water, dipped in 5% RBPP in 50% lemon juice, dipped in 10% RBPP in 50% lemon juice all seasoned with cinnamon powder, and a control formulation. The biochemical analysis showed that the total phenolic content (2780.01 ± 68.38 mg GAE/100 g DM) and antioxidant activity of apple snacks significantly increased (503.96 ± 1.83 µmol TE/g DM). Sensory evaluation indicated that snacks with beetroot peel powder and lemon juice achieved the highest scores in colour, flavour, and acceptability. These results demonstrate that the valorisation of beetroot peel has the potential to reduce agro-industrial waste and also enhance the nutritional and functional quality of apple snacks. It is recommended that beetroot peel be further explored as a cost-effective natural ingredient to develop healthier, value-added snack products within a circular economy framework. Full article
(This article belongs to the Section Nutraceuticals, Functional Foods, and Novel Foods)
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12 pages, 1441 KiB  
Article
The Quality of Lip Balm Produced with Grape Pomace Addition
by Patrycja Łusiak, Paulina Kęska, Jacek Mazur, Monika Wójcik and Paweł Sobczak
Sustainability 2025, 17(13), 6146; https://doi.org/10.3390/su17136146 - 4 Jul 2025
Viewed by 389
Abstract
In recent years, there has been growing consumer interest in foods and cosmetics containing ingredients of natural origin. During the production process, a by-product of pomace is generated, which is regarded as a dispensable product by the food industry. However, studies have clearly [...] Read more.
In recent years, there has been growing consumer interest in foods and cosmetics containing ingredients of natural origin. During the production process, a by-product of pomace is generated, which is regarded as a dispensable product by the food industry. However, studies have clearly indicated that fruit and vegetable pomace is a valuable source of many nutrients, whose beneficial effects on human health and appearance may represent an added value in its secondary use. Incorporating pomace into cosmetic products enhances their aesthetic value and can enrich them with naturally occurring polyphenols, which is in line with the circular economy model. In the present study, we determined selected mechanical properties of lip balms containing different amounts of grape pomace, for example, the kinetic friction against artificial leather, hardness, penetration performance, maximum shear force, and sample penetration resistance. Moreover, the antiradical activity against DPPH and the total phenolic content were determined, and the colour parameters were analyzed. All tests were conducted on lip balm samples containing 1, 3, and 5% fruit pomace and a control sample. Analysis of the penetration performance showed no statistically significant differences between the individual samples. However, differences in the values of other physical properties were noted. Moreover, the antiradical activity against the synthetic radical DPPH and the total phenolic content increases the value of lip balms with increasing amounts of pomace added. The colour of the lip balms also darkens with increasing amounts of pomace added. The innovative use of grape pomace is in line with sustainable development, and its properties enhance the effects of lip balms. Full article
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14 pages, 2494 KiB  
Article
Colour Homogenisation and Photostability of Beech Wood (Fagus sylvatica L.) as Affected by Mild Steaming and Light-Induced Natural Ageing
by Zuzana Vidholdová, Gabriela Slabejová and Eva Výbohová
Forests 2025, 16(7), 1104; https://doi.org/10.3390/f16071104 - 4 Jul 2025
Viewed by 271
Abstract
This study investigates the impact of mild steaming (105 °C and 120 °C for 12 h) on the colour characteristics and chemical stability of beech wood (Fagus sylvatica L.) during natural indoor ageing. Untreated and steamed samples of mature wood and false [...] Read more.
This study investigates the impact of mild steaming (105 °C and 120 °C for 12 h) on the colour characteristics and chemical stability of beech wood (Fagus sylvatica L.) during natural indoor ageing. Untreated and steamed samples of mature wood and false heartwood were analysed for CIELAB and CIELCh colour parameters (L*, a*, b*, C*, h°) and chemical changes using ATR-FTIR spectroscopy. Steaming resulted in a significant decrease in lightness (L*) and increased a*, b*, and C* values, producing darker and more saturated reddish-brown tones. It also reduced the visual differences between mature wood and false heartwood, enhancing colour uniformity. During the light-induced ageing period, steamed wood—particularly at 105 °C—exhibited improved colour stability, maintaining chroma and hue more effectively than untreated samples. Statistically significant interaction effects between treatment, time, and tissue type revealed that the ageing-related colour changes were jointly influenced by thermal modification and the anatomical characteristics of the wood. In the FTIR spectra, the most pronounced changes were observed in the absorption bands of the aromatic skeleton and carbonyl groups (1504 and 1732 cm−1). These findings confirm that mild steaming alters the original aesthetic properties and colour of beech wood when exposed to an indoor environment. Full article
(This article belongs to the Special Issue Phenomenon of Wood Colour)
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18 pages, 5848 KiB  
Article
Residual Mechanical Properties of Sandstone After Fire
by Ema Jankovičová, Radek Zigler and Jiří Pazderka
Buildings 2025, 15(13), 2282; https://doi.org/10.3390/buildings15132282 - 28 Jun 2025
Viewed by 237
Abstract
The impact of fire on natural stone structures is a critical concern, particularly for historical buildings. This study examines the residual mechanical properties of sandstone after exposure to high temperatures. Cylindrical sandstone samples were heated to temperatures up to 900 °C and subsequently [...] Read more.
The impact of fire on natural stone structures is a critical concern, particularly for historical buildings. This study examines the residual mechanical properties of sandstone after exposure to high temperatures. Cylindrical sandstone samples were heated to temperatures up to 900 °C and subsequently tested under uniaxial compression. The results indicate that mechanical degradation becomes significant beyond 460 °C, with compressive strength decreasing by up to 43% at 900 °C. Young’s modulus also declined substantially, while axial strain increased, indicating progressive structural weakening. Additionally, visible colour changes suggest mineralogical transformations. These findings provide essential insights into the fire-induced deterioration of sandstone, offering valuable guidance for the preservation and restoration of historical stone structures. Full article
(This article belongs to the Section Building Materials, and Repair & Renovation)
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43 pages, 856 KiB  
Review
Antioxidant Application of Clove (Syzygium aromaticum) Essential Oil in Meat and Meat Products: A Systematic Review
by Eduardo Valarezo, Guicela Ledesma-Monteros, Ximena Jaramillo-Fierro, Matteo Radice and Miguel Angel Meneses
Plants 2025, 14(13), 1958; https://doi.org/10.3390/plants14131958 - 26 Jun 2025
Viewed by 836
Abstract
The essential oil isolated from clove (Syzygium aromaticum) is used in food, medicine, cosmetics, agriculture, and aromatherapy for its antimicrobial, antioxidant, and analgesic properties. This systematic review, following the PRISMA 2020 methodology, evaluates the application of clove essential oil in meat [...] Read more.
The essential oil isolated from clove (Syzygium aromaticum) is used in food, medicine, cosmetics, agriculture, and aromatherapy for its antimicrobial, antioxidant, and analgesic properties. This systematic review, following the PRISMA 2020 methodology, evaluates the application of clove essential oil in meat and meat products to determine its effectiveness in preventing oxidative damage and improving product quality. A search was performed in various databases, obtaining 639 studies. After removing duplicates and applying inclusion and exclusion criteria, 43 relevant articles were selected. Studies published between 1999 and 2024 that evaluated clove essential oil in meat for human consumption were included, excluding research on extracts other than essential oil or supplements for animal feed. The studies suggest that clove essential oil improves parameters such as oxidative stability, colour preservation, and the reduction in reactive compounds such as thiobarbituric acid-reactive substances, thereby increasing the shelf life and safety of meat and meat products. Oxidation is reduced through free radical inhibition and lipid protection. The main variability detected includes the type of meat, application method and storage conditions. The concentrations used ranged from 2.65 mL/kg to 5%. Although variability in methodologies and concentrations used is a limitation for meta-analysis, the findings support the potential of clove essential oil as a natural alternative for preserving meat products, responding to consumer demand for safer foods free of synthetic preservatives. Full article
(This article belongs to the Special Issue Chemical Analysis and Biological Activities of Plant Essential Oils)
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25 pages, 6421 KiB  
Article
Potential of Carob Pulp Powder: Influence of Cultivar on Nutritional Composition, Antioxidant Activity, and Functional Properties
by Carme Garau, Mónica Umaña, Miquel Llompart, Ismael Velázquez, Isabel Gálvez and Susana Simal
Molecules 2025, 30(13), 2715; https://doi.org/10.3390/molecules30132715 - 24 Jun 2025
Viewed by 377
Abstract
Carob pulp powder (CPP), a by-product of Ceratonia siliqua L., is rich in bioactive compounds with potential for functional foods. This study evaluated how genetic variability among cultivars affects the nutritional composition and functional quality of CPP. Nineteen cultivars from Majorca (13), Ibiza [...] Read more.
Carob pulp powder (CPP), a by-product of Ceratonia siliqua L., is rich in bioactive compounds with potential for functional foods. This study evaluated how genetic variability among cultivars affects the nutritional composition and functional quality of CPP. Nineteen cultivars from Majorca (13), Ibiza (4), and two open-flowering selections were grown under identical conditions in Majorca, Spain. CPP samples showed high dietary fibre (22.6–47.4 g/100 g dry matter), total sugars (22.5–62.5 g/100 g dm), and antioxidant activity (11.1–78.4 µmol TE/g dm, CUPRAC method). Significant differences among cultivars were observed in protein and fructose content, fatty acid profiles, antioxidant activity, colour, acidity, and functional properties like water- and oil-holding capacities. Principal component analysis distinguished the Ibiza cultivars by higher soluble solids, fructose, and stearic acid content but lower antioxidant activity. Open-flowering selections exhibited the highest antioxidant and water retention capacities. These results confirm that genetic origin strongly influences CPP’s nutritional and functional traits, endorsing its use as a natural, health-promoting ingredient for functional food development. Full article
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22 pages, 3533 KiB  
Article
Spatial Perception Differences in Mountain City Park for Youth Experience: A Case Study of Parks in Yuzhong District, Chongqing
by Cong Gong, Xinyu Yang, Changjuan Hu and Xiaoming Gao
Sustainability 2025, 17(12), 5581; https://doi.org/10.3390/su17125581 - 17 Jun 2025
Viewed by 437
Abstract
Traditional park designs no longer meet the diverse needs of young users amid rising visitor numbers and environmental challenges. Exploring the impact of mountain city parks on youth is crucial, yet localised studies on their spatial perceptions in such unique environments are lacking. [...] Read more.
Traditional park designs no longer meet the diverse needs of young users amid rising visitor numbers and environmental challenges. Exploring the impact of mountain city parks on youth is crucial, yet localised studies on their spatial perceptions in such unique environments are lacking. Landscape design based on spatial perception evaluation offers a promising approach for renewing mountain parks to address these complex needs. Therefore, a pilot study was conducted in Chongqing’s Pipa Mountain and Eling Parks, involving questionnaire surveys and on-site spatial data collection. Using principal component analysis to select the visual and auditory indicators most related to environmental satisfaction in the overall park and various types of gathering spaces, the results showed that the first principal component of the visual environment in the entrance platform and key nodes (r = 0.41, r = 0.45), as well as the first principal component of the auditory environment in the entrance platform, path platform, and elevated points (r = 0.67, r = 0.85, r = 0.68), all showed significant positive correlations with environmental satisfaction (p < 0.01). Moreover, naturalness and aesthetics were identified as the main factors influencing environmental satisfaction. A random forest model analysed nonlinear relationships, ranking spatial factors by importance. Simultaneously, SHAP analysis highlighted the effects of key factors like elevation changes, green view index, colour diversity, and natural elements. Elevation changes were positively correlated with satisfaction at elevated points but showed a negative correlation in the overall park environment and other gathering spaces. This study explored space-perception dynamics in mountain city parks, proposing strategies to improve environmental quality in various gathering spaces and the park. These findings support creating liveable mountainous environments and guide “human-centred health,” quality enhancement, and sustainable development in renewing mountain city parks. Full article
(This article belongs to the Section Sustainable Urban and Rural Development)
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10 pages, 2004 KiB  
Proceeding Paper
Development of Technology for Candy Caramel with Barberry Powder and Sugar Substitute Isomaltitol
by Oksana Sema, Olena Aksonova, Anastasiia Sachko and Sergey Gubsky
Eng. Proc. 2025, 87(1), 73; https://doi.org/10.3390/engproc2025087073 - 10 Jun 2025
Viewed by 387
Abstract
Confectionery products, particularly caramel, often have low nutritional value and a high glycaemic index, necessitating the development of functional alternatives. This study aimed to create candy caramel with a reduced glycaemic index and enhanced nutritional properties by incorporating isomaltitol and invert syrup as [...] Read more.
Confectionery products, particularly caramel, often have low nutritional value and a high glycaemic index, necessitating the development of functional alternatives. This study aimed to create candy caramel with a reduced glycaemic index and enhanced nutritional properties by incorporating isomaltitol and invert syrup as sugar substitutes and fortifying it with dried barberry (Berberis vulgaris L.) powder in amounts of 1%, 2.5%, 5%, and 10% (w/w). Barberry powder, rich in bioactive compounds and essential minerals, also acts as a natural colourant. The powder’s microstructural characteristics were assessed using laser diffraction, while its elemental composition was confirmed via atomic adsorption spectroscopy. The samples of caramel were evaluated using physicochemical and sensory analysis methods. The results showed that the addition of barberry powder enriches caramel with sodium, potassium, iron, manganese and zinc. The increase in the content of barberry in sweets was accompanied by an increase in titratable acidity and a decrease in pH. Sensory evaluation identified 2.5–5% barberry powder as optimal, yielding a product with attractive colour and flavour. Higher concentrations resulted in excessive acidity and darker coloration, which were deemed undesirable. The developed formulation demonstrates the potential of candy caramel as a functional food product, offering improved nutritional and sensory attributes. This approach provides a promising solution for addressing the health and dietary concerns associated with traditional confectionery products. Full article
(This article belongs to the Proceedings of The 5th International Electronic Conference on Applied Sciences)
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16 pages, 6101 KiB  
Article
Deciphering Ageing Effects in Green-Dyed English Wool Carpet Yarns from the 1840s
by Terry T. Schaeffer, Jacob Mobberley and Laura Maccarelli
Heritage 2025, 8(6), 216; https://doi.org/10.3390/heritage8060216 - 7 Jun 2025
Viewed by 652
Abstract
In 1842, carpet manufacturer W.H. Worth of Kidderminster, England, began assembling a sample book of wool yarns dyed with natural dyestuffs. This paper reports on a study of the “Greens” section, which contains sixteen yarn samples—six still green and ten now ranging from [...] Read more.
In 1842, carpet manufacturer W.H. Worth of Kidderminster, England, began assembling a sample book of wool yarns dyed with natural dyestuffs. This paper reports on a study of the “Greens” section, which contains sixteen yarn samples—six still green and ten now ranging from tan to dark brown. The accompanying recipes list similar ingredients: old fustic and either “mixture” or extracet of indigo. To verify whether Worth’s recipes were followed, the yarns were analyzed using HPLC-DAD and FORS. Additionally, mock-ups were prepared according to Worth’s green dye recipes and subjected to thermal ageing to explore potential causes of discoloration. Preliminary analysis of the historic samples revealed that the discoloured yarns contain both indigo and indigo carmine, while the still-green samples contain only indigo carmine. This suggests that one or more components of the indigo vat may have contributed to discoloration. To test this hypothesis, contemporary wool yarns were dyed using a Worth green recipe, with and without indigo, at varying pH levels. These were thermally aged, and their colour changes monitored. HPLC-DAD and FORS analyses of the mock-ups were compared to the historic samples to identify dyeing conditions that may have led to the observed browning. Full article
(This article belongs to the Special Issue Dyes in History and Archaeology 43)
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24 pages, 3308 KiB  
Article
The Latest Achievements in the Design of Permanent Fillings for Conservative Dentistry Based on Indenoquinoxaline Derivatives as Photoinitiators of Visible-Light Polymerization: Mass and Colour Stability
by Ilona Pyszka, Oliwia Szczepańska and Beata Jędrzejewska
Int. J. Mol. Sci. 2025, 26(11), 5424; https://doi.org/10.3390/ijms26115424 - 5 Jun 2025
Viewed by 463
Abstract
The demand for polymer composite materials in the dental market is increasing every year. This rise is due to their excellent properties and ongoing technological advancements. The goal of this study was to develop new photoinitiators included in the liquid organic matrix, which [...] Read more.
The demand for polymer composite materials in the dental market is increasing every year. This rise is due to their excellent properties and ongoing technological advancements. The goal of this study was to develop new photoinitiators included in the liquid organic matrix, which is one of the main components of dental composites. Therefore, a series of compounds based on the indenoquinoxaline skeleton was synthesized, differing in the substituent. The spectroscopic properties of these compounds allowed their use as visible-light photoinitiators of radical polymerization in combination with (phenylthio)acetic acid. In addition to the polymerization kinetics, the lifetime and quantum yield of the triplet-state formation and the rate constants of its quenching by (phenylthio)acetic acid were determined. The durability of the designed composites was also assessed. Ageing tests included hydrothermal ageing, allowing for the determination of sorption, solubility, and mass change. Solutions imitating the oral cavity environment—distilled water, artificial saliva, n-heptane, and 3% acetic acid—as well as solutions containing pigments were used for these studies. Determination of the mass change and colour stability allowed for the assessment of how these materials react to long-term exposure in the oral environment. It was found that the solution simulating the natural oral environment has a significant impact on the hydrolytic stability and colour stability of the materials. Full article
(This article belongs to the Special Issue Application of Biotechnology to Dental Treatment)
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17 pages, 4080 KiB  
Article
Green Synthesis and Characterization of Iron Oxide Nanoparticles Using Egeria densa Plant Extract
by Maruf Olaide Yekeen, Mubarak Ibrahim, James Wachira and Saroj Pramanik
Appl. Biosci. 2025, 4(2), 27; https://doi.org/10.3390/applbiosci4020027 - 2 Jun 2025
Viewed by 1260
Abstract
An aqueous leaf extract of Egeria densa was used to green-synthesize iron (II) and iron (III) oxide nanoparticles from ferrous sulphate and ferric chloride, respectively. The successful green synthesis of the nanoparticles was confirmed through UV–visible spectroscopy, and the colour of the mixtures [...] Read more.
An aqueous leaf extract of Egeria densa was used to green-synthesize iron (II) and iron (III) oxide nanoparticles from ferrous sulphate and ferric chloride, respectively. The successful green synthesis of the nanoparticles was confirmed through UV–visible spectroscopy, and the colour of the mixtures changed from light-yellow to green-black and reddish-brown for FeO–NPs and Fe2O3–NPs, respectively. The morphological characteristics of the nanoparticles were determined using an X-ray diffractometer (XRD), a Fourier transform infrared spectrophotometer (FTIR), a transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDX). The UV–Vis spectrum of the FeO–NPs showed a sharp peak at 290 nm due to the surface plasmon resonance, while that of the Fe2O3–NPs showed a sharp peak at 300 nm. TEM analysis revealed that the FeO–NPs were oval to hexagonal in shape and were clustered together with an average size of 18.49 nm, while the Fe2O3-NPs were also oval to hexagonal in shape, but some were irregularly shaped, and they clustered together with an average size of 27.96 nm. EDX analysis showed the presence of elemental iron and oxygen in both types of nanoparticles, indicating that these nanoparticles were essentially present in oxide form. The XRD patterns of both the FeO–NPs and Fe2O3–NPs depicted that the nanoparticles produced were crystalline in nature and exhibited the rhombohedral crystal structure of hematite. The FT-IR spectra revealed that phenolic compounds were present on the surface of the nanoparticles and were responsible for reducing the iron salts into FeO–NPs and Fe2O3–NPs. Conclusively, this work demonstrated for the first time the ability of Elodea aqueous extract to synthesize iron-based nanoparticles from both iron (II) and iron (III) salts, highlighting its versatility as a green reducing and stabilizing agent. The dual-path synthesis approach provides new insights into the influence of the precursor oxidation state on nanoparticle formation, thereby expanding our understanding of plant-mediated nanoparticle production and offering a sustainable route for the fabrication of diverse iron oxide nanostructures. Furthermore, it provides a simple, cost-effective, and environmentally friendly method for the synthesis of the FeO–NPs and Fe2O3–NPs using Egeria densa. Full article
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