Color Intensity Research Articles

Ultrasonic Assisted Environmentally Friendly Extraction of Natural Dyes From Beta vulgaris for the Coloration of Silk Fabric Using Different Mordants

ABSTRACTConsidering the indispensability of environmental protection, the utilization of natural ingredients as sustainable and eco‐friendly alternatives to synthetic dyes in fabric dyeing is of great significance. Betacyanins are naturally sourced pigments of red‐violet color that have the propensity to be fixed to mordanted substrates with reasonable permanency. In this study, the betacyanins sourced from beetroot (Beta vulgaris) were used to dye pre‐mordanted silk fabrics employing ultrasonication. In addition, a comparative analysis of the effects of five different mordants such as orange‐peel extracts, lemon peel extracts, tannic acid, ferrous sulfate, and alum on the color strength and fastness of beetroot‐dyed silk fabrics was presented in this research. For the characterization of the extracted dye, undyed, dyed, and mordanted silk fabric, infrared spectroscopy was performed. To observe the interaction of extracted dye and silk fabric, scanning electron microscopy was also accomplished. The outcomes of the characterization validated the successful extraction of dyes from beetroot and dyeing silk fabric with it. The values of color intensity (K/S), CIE L* a* b*, and CIE L* c* h* were measured using a reflectance spectrophotometer. At the same time, dry and wet rubbing and lightfastness ratings of dyed silk fabrics were determined according to the ISO standards. When 5% (o.w.f.) ferrous sulfate was used in pre‐mordanting, the ratings of colorfastness to wash, rub, and light ranged from 4 to 4/5, and the K/S value of the final sample was 4.88, which is higher than the K/S values of any other dyed samples. In contrast, the performance of 5% (o.w.f.) lemon peel extracts as a mordant was remarkably higher than orange peel extracts and even better than alum and tannic acid to some extent. The beetroot‐dyed silk fabric pre‐mordanted with 5% lemon peel exhibited a K/S value of 4.32, and the overall colorfastness rating ranged from 3/4 to 4/5. In conclusion, beetroot extracts hold the promise of being utilized as a sustainable replacement for environmentally harmful synthetic dyestuff in silk dyeing. Furthermore, in silk dyeing with beetroot extract, lemon peel extract is a potent alternative to ferrous sulfate as a mordant.

Decolorizing of seaweed extract by electrocoagulation

Electrocoagulation (EC) is a technique commonly used in wastewater treatment to remove biological and chemical contaminants, but the process has the potential to be used in clarifying plant extracts for the isolation and identification of secondary metabolites. Seaweed extracts contain copious amounts of chlorophyll and other pigments that obscure the characterization of secondary metabolites such as phenolic acids and flavonoids. In place of conventional methods that utilize solvents, EC can potentially be applied to clarify and fractionate extracts. In this research, an EC duration of 30 min (22 V, 0.3–0.5A) with aluminum electrodes resulted in a significant decrease, about 76%, of chlorophyll and 70% of carotenoids from seaweed extract measured at 666 nm and 410 nm. The decrease in extract green and yellow color intensity also mirrored a decrease in total phenolic content (TPC) of the extract from 54 ± 1.55 mg GAE/g DW to 3.2 ± 0.01 mg GAE/g DW after 30 min of EC. However, the phenolic acid profile of the extract after electrocoagulation via HPLC-RP indicated the removal of an interference probably caused by polymeric compounds from the extract, thus leaving the simple phenolic acids in solution for detection. The major phenolic acids detected in seaweed crude extract were p-coumaric, o-coumaric, ferulic and syringic acid. Flavonoids detected included catechin, epicatechin, quercetin-3-glucoside and rutin. The results of this study show the potential of replacing conventional plant extract purification methods with a green method that requires no additional solvent.Graphical

Intensity characterization and color appearance model extending for Helmholtz-Kohlrausch effect in laser display

Intensity characterization and color appearance model extending for Helmholtz-Kohlrausch effect in laser display

Inter-regional characterisation of New Zealand pinot noir wines: Correlation between wine colour, monomeric and polymeric phenolics, tannin composition, antioxidant capacity, and sensory attributes

A total of 116 New Zealand Pinot Noir wines from Central Otago (CO), Marlborough (MLB), and Martinborough (MTB) were analysed for colour, monomeric and total phenolics, antioxidant capacity, and tannins using colourimetric and HPLC methods. Correlations among chemical compositions and analytical techniques were examined. Additionally, a sensory study assessed wine colour and five mouthfeel attributes. Discriminant analyses revealed significant regional characteristics. CO wines displayed unique monomeric anthocyanin profiles and were perceived as softer on the palate. MLB wines showed higher residual sugar but lower colour intensity and tannin concentration. MTB wines exhibited higher colour and robust mouthfeels, linked to higher colour absorbances, polymeric pigments, and tannins. Mouthfeel attributes correlated significantly with wine total phenolics, MCP and HPLC tannin measurements, and the degree of tannin polymerisation (mDP). The combined chemical and sensory data enhanced regional differentiation, demonstrating the importance of integrating comprehensive chemical measurements with sensory evaluations for thorough wine classification.

Innovative dual-mode miniaturized nitrite sensor: Incorporating colorimetric and electrochemical detectors for comprehensive monitoring on a single platform

This study introduces a novel, miniaturized analytical platform for a comprehensive range of founded nitrite concentrations on a single, portable device. Nitrites, essential for extending shelf life and enhancing color, are commonly found in both natural and industrial environments. In environmental settings, it is important to detect low nitrite concentrations, industrial applications, such as in the food industry, require handling higher concentrations effectively. This groundbreaking approach combines colorimetry and electrochemical detection for nitrite monitoring in a single portable paper-based device (PAD). Utilizing potassium permanganate (KMnO4) as a chromogenic agent, the device enables rapid, visual detection and quantification of high nitrite concentrations via smartphone-based color intensity analysis. For sensitive detection of low-level nitrite, it incorporates a cellulose acetate-modified screen-printed electrode (CA/SPCE) with differential pulse voltammetric detection. Under optimal conditions, the proposed dual-detection platform effectively detects nitrite concentrations ranging from 0.05 to 12.5 mM. Specifically, it covers (0.05 to 0.6 mM using electrochemical detection and 0.5 to 12.5 mM through colorimetric analysis. High nitrite levels produce a faded color in the test zone, while low or undetectable color changes trigger electrochemical analysis for enhanced precision. This PAD platform is portable, cost-effective, and minimizes reagent usage. Importantly, the method’s detection limit aligns with the World Health Organization’s acceptable daily nitrite intake in drinking water (3 mg L−1, approximately 65 µM), making it a practical tool for nitrite screening.

Using Hybrid Coating to Fabricate Highly Stable and Expandable Transparent Liquid Marbles.

Liquid marbles (LMs) are microliter-scale droplets coated with hydrophobic solid particles. The particle size and hydrophobicity of the surface coating determine their properties, such as transparency, expandability, and resistance to evaporation and coalescence, one or more of which can be critical to their application as microreactors. This study reports the use of a mixture of two different hydrophobic powders for fabrication of LMs for colorimetric assays: trichloro(1H,1H,2H,2H-perfluorooctyl) silane-linked silica gel (modified silica gel (MSG), particle size: 40-75 μm) and hexamethyldisilazane-linked fumed silica (modified fumed silica (MFS), average aggregate length: 200-300 nm). The hybrid coating mixture (MIX) prepared by mixing these MSG and MFS powders in a ratio of 3:7 (w/w), respectively, contained particles of different sizes as well as different hydrophobicity as the silane linked to MSG is more hydrophobic than the one linked to MFS. LMs fabricated using MIX as the surface coating were characterized and compared to LMs coated with MSG or MFS alone. It was observed that MIX LMs were comparable to the MFS LMs in transparency (higher than the MSG LMs), expandability (more than 20 times their initial volume), and stability against evaporation (for more than 4 h at 78% relative humidity at 26 °C). However, in terms of resistance to coalescence, the MIX LMs showed a resistance comparable to that of MSG LMs, much higher than that of MFS LMs. Further experiments demonstrated that it is the presence of the particles of different sizes (MSG particles are ∼100 times larger than MFS) that improves the resistance to coalescence rather than the higher hydrophobicity of the MSG. Three different colorimetric assays were performed in the MIX LMs, and the results obtained were comparable in accuracy and precision to those obtained in a standard polystyrene microwell plate system. Low quantities of the analytes could be detected and quantified, as evidenced by the limit of detection (alkaline phosphatase (AP): 0.18 μg/mL; bovine serum albumin (BSA): 2.28 μg/mL; and chymotrypsin: 3.69 μM) and limit of quantification (AP: 0.59 μg/mL; BSA: 12.29 μg/mL; and chymotrypsin: 7.59 μM) values. Color intensities in LMs were quantified using a smartphone application, which provides the added benefit of an instrument-free approach. These findings highlight the potential of using LMs stabilized with mixtures of nano- and microparticles as robust, versatile microreactors for portable and sensitive colorimetric assays, paving the way for more accessible and efficient diagnostic tools.

Integrating Deep Learning and CCTV for Real-Time Health Monitoring in Schools

Abstract—This project proposes a real-time health monitoring system for schools, integrating deep learning techniques with CCTV technology to enhance student well-being. By utilizing advanced computer vision algorithms, the system analyzes video feeds from cameras to continuously assess students' health, focusing on facial expressions and behaviors. The DeepFace model is employed to detect and recognize individual students and analyze their facial expressions for signs of distress or other health-related issues. When the system identifies concerning health indicators, it generates immediate alerts, which are sent to school administrators through a user-friendly web interface. This interface allows administrators to monitor health analytics, view real-time alerts, and access historical data for effective decision-making and intervention. The proposed framework offers a proactive approach to student health monitoring, ensuring a safer and more supportive school environment. Keywords—DeepFace, CCTV, Pattern recognition, colour intensity

Simultaneous two colour intensity interferometry with H.E.S.S.

Abstract In recent years, intensity interferometry has been successfully applied to the Imaging Atmospheric Cherenkov Telescopes H.E.S.S. , MAGIC, and VERITAS. All three telescope systems have proven the feasibility and capability of this method. After our first campaign in 2022, when two of the H.E.S.S. telescopes in Namibia were equipped with our external setup and the angular diameter of two stars was measured, our setup was upgraded for a second campaign in 2023, where the goal is to perform simultaneous two colour measurements. The second campaign not only involves a third equipped telescope, but also each mechanical setup now includes two interference filters at two different wavelengths (375 nm and 470 nm) with a broader bandwidth of 10 nm. This enables having simultaneous two-colour measurements, which yields information about the star’s physical size at different wavelengths. This is the first time that simultaneous dual-waveband intensity interferometry measurements are performed. The angular diameter results of the 4 stars, Mimosa (β Cru), Eta Centauri (η Cen), Nunki (σ Sgr) and Dschubba (δ Sco), are reported, where the effects of limb darkening are also taken into account.

MXene Bimetallic Coating Synergistic Enhanced Colorimetric-Raman Dual Signal-Based Immunochromatographic Assay for Advancing Detection Performance.

Herein, a three-dimensional thin film-like multifunctional MXene bimetallic coating material (Ti3C2@Au-Ag) with strong color intensity, high surface-enhanced Raman scattering (SERS) activity, and strong antibody affinity (1.00 × 108 M-1) was prepared. It was the first time that Ti3C2@Au-Ag-based colorimetric-SERS dual-signal immunochromatographic assay (ICA) was developed for the detection of dexamethasone, achieving the limits of detection of 0.0089, 0.14, and 0.084 μg/kg for milk, beef, and pork in colorimetric mode and 0.0015, 0.060, and 0.075 μg/kg in SERS mode. It was up to 200-fold more sensitive than the reported ICAs. The recoveries were 82.0%-112.6%, and the coefficients of variation were 1.4%-13.7%. The Ti3C2@Au-Ag-ICA was verified by LC-MS/MS in the application on 30 real samples with a correlation coefficient greater than 0.98. This study can provide efficient theoretical and practical value for the development of a colorimetric-SERS dual-signal immunoassay platform.

Unraveling the unique microbiota and metabolites in three different colors Jiangqu through multidimensional analysis

Tri-colored Jiangqu, including white (WQ), yellow (YQ), and black (BQ)-color Daqu, significantly influence fresh Baijiu yield and quality. The differences in attributes of these Jiangqu types, sourced from two renowned Baijiu enterprises, were investigated using multi-omics approaches. Color intensity negatively correlated with ammonia nitrogen content, but positively with pyroglutamic acid content. 182 volatiles and 291 non-volatiles were identified, with each types exhibiting unique metabolites. Esters, pyrazines, ketones and phenols were predominant in WQ, YQ, and BQ, respectively. The content of peptides, amines, and amino acids with derivatives also showcased the differences of microbiota and metabolic pathways among tri-colored Jiangqu. BQ's characteristic components of L-Tyrosine and acetyl tributyl citrate were closely associated with melanin formation. In YQ, Scopulibacillus and Rhizopus correlated positively with tetramethylpyrazine. Moreover, the bacterial community significantly influenced the metabolic profiles, and synergistic interactions between fungal and bacterial communities were crucial in determining metabolite abundance.

The Effect of High-Pressure Processing on the Copigmentation and Storage Stability of Polyphenols with Anthocyanin Monomers

This study aims to determine the effect of different high-pressure processing (HPP) conditions (100 MPa/300 MPa/500 MPa; 2 min/4 min/6 min) on copigmentation, specifically between chlorogenic acid (CA), epicatechin (Epi), gallic acid (GA), malvidin-3-O-galactoside (Mv-3-O-gal), and malvidin-3-O-arabinoside (Mv-3-O-ara), as well as the storage stability of the copigmentation solutions. The results showed that the influence of different HPP treatment conditions on copigmentation was not significant. HPP treatment did not significantly affect the λmax, peak absorption, color parameters, and Mv-3-O-gal anthocyanin content when applied alone or in combination with CA and Epi. However, the color intensity and a* value of Mv-3-O-gal with GA decreased by 3.2% (p < 0.05). The absorption peak, color, and content of Mv-3-O-ara were not affected by HPP alone or during copigmentation with CA, Epi, and GA. In addition, CA had the best effect on the co-coloring of Mv-3-O-gal, while GA was more successful in affecting Mv-3-O-ara during the storage period. Molecular dynamics simulations indicated that the aromatic ring of CA was closest to the A-C plane of Mv-3-O-gal (3.70 Å), resulting in a closer π-π stacking distance and higher bond energy. The favorable impact of GA on Mv-3-O-ara was because the A-C plane aromatic ring of Mv-3-O-ara and the aromatic D ring of GA formed “sandwich” stacking. The results indicated that combining HPP with polyphenols improved color and could be used to process raw materials containing malvidin, such as blueberries.

Bleaching efficacy of in-office bleaching with violet light using low-concentration hydrogen peroxide nanoparticulate photocatalyst gel: A randomized controlled trial

ObjectiveThis randomized controlled trial aimed to evaluate the bleaching efficacy and tooth sensitivity (TS) of participants submitted to different application protocols of in-office bleaching with violet light using 6 % hydrogen peroxide (HP) nanoparticulate photocatalyst gel. Materials and methodsSixty-six participants were randomized and bleached using either a 6 % HP (Nano White, DMC), and/or violet light (Bright Max Whitening, MMOptics), according to the following protocols: 1) only violet light (VIOL); 2) only bleaching gel application (BG) and; 3) combined bleaching gel application + violet light (BG+VIOL). The bleaching efficacy was evaluated with the Vita Easyshade spectrophotometer, Vita Classical and Vita Bleachedguide scales. The risk and intensity of TS were recorded using a 0–10 visual analogue scale (VAS) and a 0–4 numerical scale (NRS). Color change and intensity of TS values were compared using one-way ANOVA and Tukey's test were used. The absolute risk of TS was compared using the Chi-square test (α = 0.05). ResultsA significant and higher degree of bleaching was observed in the BG and BG+VIOL groups compared to the VIOL group (p < 0.003). Despite no significant differences in the risk (p > 0.07) and intensity (p > 0.28) of TS among groups, a higher risk of TS was observed in the BG and BG+VIOL groups. ConclusionsUsing VIOL reduced the risk of TS but did not improve bleaching. However, BG+VIOL with low-concentration HP nanoparticulate photocatalyst gel achieved equal efficacy and was less likely to cause TS compared to BG.

Exploring the marination of colonial cheese into wine and vinegar through ripening: Physicochemical characteristics, sensorial attributes and emotions evoked

In southern Brazil, colonial cheese is a very popular traditional dairy and plays significant economic and cultural roles. Innovation in traditional foods is crucial for continued market growth. Marinating cheeses in wine is a known practice, however the use of vinegar is traditional on informal scale in southern Brazil, but little explored. This study aimed to evaluate the impact of marinating colonial cheese in wine and vinegar during ripening. Colonial cheeses were immersed whether wine or vinegar and ripped for 30 days. Colour, moisture, texture and pH parameters were evaluated during the ripening period and cheeses in the end of 30-day maturation were subjected to acceptance, perception of attributes and evoked emotions analyses. Drivers of purchasing were also explored. Cheeses immersed in vinegar showed a greater loss of moisture and a decrease in pH. The surface of cheeses immersed in wine showed a dark and reddish color immediately after immersion in wine, with gradual darkening until the tenth day of ripening. Immersion of the product into vinegar implied on cheeses with surface with a less intense coloration (red and dark). Hardness increased through ripening and were higher on marinated samples. The control cheeses showed greater acceptance and evoked positive emotions, while the experimental cheeses evoked more negative emotions. Cheeses marinated in wine and vinegar incorporated characteristic aroma and flavors of the beverage used. Hedonic aspects and the presence of new flavors were the main drivers of purchasing the cheeses. Thus, immersing cheese in wine or vinegar impacts the maturation process, providing different effects on physicochemical and sensorial features of the product.

Hybrid aerogels of spirulin and whey proteins as novel cellular solids

This work proposes a new strategy to obtain cellular solids of spirulin (SP) cells and whey protein (WP) using the aerogel production process. To this aim, aqueous suspensions containing 20 g/100 g of a mixture of WP and SP in different ratios, were submitted to thermal gelation. The obtained hydrogels were characterised by an intense green colour and the typical unpleasant fishy odour of SP. Hydrogels were then submitted to ethanol solvent exchange and supercritical-CO2 drying, leading to hybrid aerogels, which were analysed for physical properties (colour, density, volume contraction, firmness, microstructure). The conversion of hydrogels into aerogels partially reduced their green colour. The increase in SP in the aerogel progressively decreased its firmness, so that the aerogels obtained from suspensions containing more than 10 g/100 g spirulin were not able to maintain the continuity of the aerogel network. The latter was demonstrated by SEM to consist of dried WP microgels organised in a tri-dimensional architecture embedding SP cells. The aerogel obtained from 10 g/100 g SP suspension did not swell or disintegrate upon absorption of both water and oil. Sensory analysis also showed this sample to have negligible SP odour. These results open new possibilities in the development of hybrid cellular solids with neutral sensory properties, posing the basis for a new approach to the engineering of food tissue analogues.

Postharvest LED Treatment of Tomatoes Harvested at an Early Stage of Coloration

The tomato plant is one of the most important vegetable crops, with a global production of around 188 million tones. The greatest losses in quantity and quality occur during storage, transport, and sale. The aim of the study was to determine the effect of irradiation on the quality and storability of the tomato ‘Tomimaru Muchoo’. Fruit harvested at the turning ripening stage were illuminated for the first two weeks at 15 °C with four visible LED light spectra, with different percentages of blue, green, and red light (BGR). The illumination times were 4 and 8 h per day (hpd). After illumination, the tomatoes were stored at 20 °C in the dark for 4 weeks. Immediately after 14 d of illumination, all tomatoes were fully ripe, although they showed varying red color intensity. In addition, all fruit retained very good quality and freshness. During further storage at 20 °C, there was a gradual decrease in tomato quality. However, LED lighting helped delay softening, reduce rotting, and thus maintain better tomato quality. Longer daily irradiation (8 h) delayed tomato senescence to a greater extent than shorter irradiation (4 hpd). Comparing the spectra, the greatest reduction in softening and rotting occurred in tomatoes illuminated with the spectrum containing the highest amount of blue light (56%). These tomatoes also maintained the lowest color index (a*/b*) throughout storage at 20 °C, which was especially evident in tomatoes that had been illuminated for 8 hpd. The light treatment influenced the maintenance of higher levels of ascorbic acid and antioxidant activity in tomatoes. However, irradiation did not increase the polyphenol content of tomatoes or reduce the lycopene levels in the fruit. Overall, the results showed that LED irradiation during storage improves storability and affects the health-promoting components of tomato fruit. It is a promising tool for reducing losses of horticultural produce.

Evaluation of a rapid test for point-of-care detection of cardiac troponin I in serum of healthy and diseased dogs and cats.

(1) To compare the results of a rapid test for qualitative detection of cardiac troponin I (cTnI) values >1ng/mL with those obtained using a reference quantitative method and (2) to perform a semiquantitative assessment of rapid test results using this point-of-care (POC) assay. Prospective cross-sectional study from April 2015 to November 2020. Secondary referral hospital. Eighty dogs and 20 cats, with and without cardiovascular disease. None. Serum samples were obtained, and cTnI rapid test was conducted in parallel with chemiluminescence assay (reference standard). Positive results from the rapid test were further classified as mild and strong positives, based on subjective assessment of the color intensity of the test line. Rapid test was deemed valid in all patients. There was agreement for positive samples between the qualitative and quantitative techniques in 31 dogs and 5 cats, and for negative samples in 43 dogs and 13 cats, resulting in a strong and moderate agreement, respectively. There was a significant difference between color scale groups. The rapid test assessed provides a feasible POC option to determine concentrations of cTnI >1ng/mL in dogs and cats and shows a moderate to strong agreement with a validated conventional quantitative assay. Furthermore, semiquantitative assessment allows estimation of the magnitude of the elevation.

Enhancing coloration performance and colour fastness of nano‐pigment ink‐jet‐printed blended fabrics through cationic and water‐repellent surface modification

AbstractThe coloration performance and colour fastness properties, crucial for industrial textile printing, depend on the spreading and fixation behaviour of ink‐jet droplets on porous fabrics. Current nano‐pigment‐based ink‐jet applications provide unstable results for these properties, especially for synthetic and blended fabrics. This study focuses on cellulose‐based blended fabrics as substrates to modify the wetting properties of fabrics through cationic and water‐repellent treatments, to improve the coloration performance and colour fastness systematically. The study conducted analytical experiments to analyse the surface element composition, ion potential and surface morphology of the fabrics. Differences in printing colour and pattern performance were attributed to the behaviour of ink droplet spreading on the fabric surface and inside the fabric, including wetting time, colourant distribution, and ring shape. The results indicate that ink droplet spreading on fabrics significantly influences printing pattern sharpness, including edge clarity and colour intensity, which can be improved through surface modification, including cationic and water repellent treatment. The use of blended fabrics treated with 1% cationic modifier and 0.05% fluorine‐containing water repellent resulted in effective suppression of droplet formation and significant enhancement of colour performance and fastness. Furthermore, as the ink droplet volume decreased from 5 to 1 μL, the coffee ring effect on the fabric treated with the water repellent agent gradually diminished, leading to improved printing sharpness during the printing process.

Optimization of Acetylcholinesterase and Sucrose Concentration using Response Surface Methodology (RSM) Approach in the Development of Paper-Based Biosensor for Pesticides Detection

Excessive use of pesticides, particularly organophosphate pesticides (OPs), to increase agricultural productivity may give a risk to consumers if consumed as these pesticides are neurotoxic substances. To increase agricultural productivity, fruits and vegetables are frequently treated with excessive pesticides, particularly organophosphate pesticides (OPs). Several methods have been studied and developed to identify pesticide residue in crops, however the standard laboratory procedures for OPs analysis involves the use of HPLC or GC-MS. These methods are complex in sample preparation and require expert labor to operate. Paper-based biosensors are low-cost platforms for fast detection in the field, offering an easy and reusable option. In this study, a colorimetric paper-based biosensor based on immobilizing acetylcholinesterase (AChE) using sol-gel silica matrices and indoxyl acetate is developed. The Response Surface Methodological (RSM) approach was used to optimize AChE concentration and sucrose as a stabilizer, allowing simultaneous optimization of multiple variables using smaller-size datasets. This study used the central composite design (CCD) fractional factorial design using Design Expert 7.0 software. A quadratic model was selected to represent both immobilization yield and relative AChE activity responses. The model was evaluated using ANOVA values and Lack of Fit test which confirmed that the quadratic models for both responses are suitable for experimental data. Validation of the model demonstrates that the predictive model accurately represents of the validation research. The Limit of Detection (LoD) of the biosensor for pure profenofos pesticide after a 20-minute incubation time is 1 ppm, as indicated by a 32.55 % decrease in color intensity. After a week of storage at 4 °C, the biosensor showed a loss of 5.92 % on immobilization yield and 2.55 % on relative activity indicating a good storage stability. The mean value of lettuce samples was 200.60 ± 1.2 a.u, with pesticide concentration of 2.57 ± 1.2 ppm (n=3). HIGHLIGHTS Incorporating AChE into the sol gel matrices is a great way to enhance the stability of the enzymatic colorimetric pesticide detection. Response Surface Methodology (RSM) is considered as useful for optimizing response level of AChE and sucrose. Combination of optimum AChE and sucrose concentration show beneficial effect on the stability of the biosensor. GRAPHICAL ABSTRACT

In Vitro Initiation, Regeneration, and Characterization of Plants Derived from Mature Tetraploid Floral Explants of Date Palm (Phoenix dactylifera L.)

A stable tetraploid date palm mutant with the potential for increased fruit size was recovered from a sectorial di-tetraploid chimera via the in vitro culture of flower explants. Callus was induced using 2,4-D, followed by shoot regeneration on a medium containing NAA and BAP and rooting with IBA. Regenerated plantlets, confirmed as tetraploid via flow cytometry, were acclimatized and grown for six years. The leaves of tetraploids exhibited significantly wider petiole bases, thicker rachis and spines, broader leaflets, and a more intense green leaf color compared to diploids. However, leaf length, spine count, and overall leaf number were reduced. This is the first report of successful tetraploid recovery from a chimeric date palm, demonstrating the potential of this technique to generate novel germplasm and highlighting the phenotypic differences associated with tetraploidy in this species.

Effect of Various Carbohydrates in Aqueous Solutions on Color Stability and Degradation Kinetics of Selected Anthocyanins During Storage.

Anthocyanins are flavonoid substances of plant origin with potential antioxidant effects. Because of their intense colors, they are used as natural dyes in food. However, their stability in food matrices is limited. This study aimed to verify the effect of selected carbohydrates on the stability of anthocyanins (cyanidin-3-O-β-glucopyranoside, cyanidin-3-O-β-galactopyranoside, cyanidin-3-O-β-rutinoside and delphinidin-3-O-β-rutinoside) during the accelerated storage test, since carbohydrates help to preserve the typical color of anthocyanins, increase their shelf-life and availability in the organism, and reduce losses during processing. Moreover, the kinetic parameters of anthocyanin degradation (Ea, k, t1/2) were determined. Sucrose was found to have the greatest potential for retarding anthocyanin degradation during storage, whereas fructose exerted an accelerating effect. Glycosidation of anthocyanin aglycone had no significant effect in terms of their stability. Anthocyanin degradation was significantly positively correlated with the change in the a* parameter (redness), and subsequently, a significant positive correlation was observed in the determination of the kinetic parameters for anthocyanins and the a* parameter. The highest stability of anthocyanins was observed in the presence of sucrose and their degradation can be predicted by the value of the a* parameter, which would also be a very fast and non-destructive method for food processing companies.