Color Products Research Articles

An IoT-based data analysis system: A case study on tomato cultivation under different irrigation regimes

The exploitation of modern technologies in heterogeneous farming scenarios with different crops cultivation is nowadays an effective solution to implement the concept of Smart Agriculture (SA). Following this approach, in this study the tomato plants’ response to different irrigation regimes is investigated through the implementation of an Internet of Things (IoT)-oriented SA data collection and monitoring system. In particular, the experimentation is conducted on tomatoes grown at three different irrigation regimes: namely, at 100%, 60%, and 30% of the Italian irrigation recommendation service, denoted as Irriframe. The proposed platform, denoted as Agriware, is able to: (i) evaluate information from heterogeneous data sources, (ii) calculate agronomic indicators (e.g., Growing Degree Days, GDD), and (iii) monitor on-field parameters (e.g., water consumption). Different plant-related parameters have been collected to assess the response to water stress (e.g., Soil Plant Analysis Development (SPAD), chlorophyll content, fluorescence, and others), along with leaf color and final production evaluations. The obtained results show that the best irrigation regime, in terms of plant health and productivity, corresponds to 60% of Irriframe, allowing significant water savings for the cultivation.

Aptasensor based on entropy-driven catalytic amplification system for the sensitive detection of acetamiprid in Chinese herbal medicine.

The traditional method of acetamiprid residue detection is difficult to operate, time-consuming, laborious and requires high professional knowledge of the detection personnel, which cannot meet the requirement of on-field rapid detection. For this reason, a colorimetric aptasensor based on an entropy-catalyzed amplification system was developed for the ultrasensitive and selective determination of acetamiprid. In the absence of acetamiprid, the aptamer and cDNA form a double-stranded structure. The formed hemin/G-quadruplex mimicking DNAzyme can catalyze the substrate ABTS to generate the colored ion ABTS- with the help of H2O2, and the solution turns blue-green. On the contrary, the presence of acetamiprid triggers the release of cDNA, which in turn initiates the entropy-driven system, resulting in the inability to form DNAzyme and therefore no blue-green color production in the solution. The quantity of acetamiprid determines the color. Under the optimal experimental conditions, the method showed a linear correlation (R2 = 0.9837) for the detection of acetamiprid in the concentration range of 0.1-100 ng/mL, with a limit of detection of 0.06 ng/mL. The developed method was used for the determination of acetamiprid in spiked Coix lacryma and Bitter almond, with recoveries in the range of 90.3-110.3%. The proposed enzyme-free and label-free assay can be developed into a simple, sensitive and rapid detection platform.

Some Biological Characteristics of Monascus Strains Isolated from a Commercial Red Fermented Rice Product

Monascus purpureus has been widely used for over 1000 years in Asian countries especially in China and Japan for the production of natural food colorants or red fermented rice. However, M. purpureus produces a mycotoxin named citrinin. Therefore, Monascus strains used in industry must be controlled for the ability of citrinin production. In Vietnam, red fermented rice products are imported and widely sold on online markets but there are no reports on their safety. From a commercial red fermented rice sold in Vietnam, two strains of M. purpureus were successfully isolated, purified, and identified based on morphological characteristics and sequencing of the internal transcribed spacer (ITS) region of rDNA. Additionally, both isolates produce citrinin, a harmful mycotoxin, similar to the reference strains of M. purpureus. Effects of nitrogen sources and initial pH values on the production of pigments and citrinin in these Monascus strains were also investigated. The results revealed the red fermented rice product containing the citrinin-producing M. purpureus strains needed to be managed, evaluated, and monitored more strictly in terms of food safety. Notably, changes in nitrogen sources and initial pH values for fungal cultivation could suppress the toxin production for the quality improvement of red fermented rice products. In addition, two isolates provided in this study are potential strains for pigment production with strict control of fermented conditions.

The Beneficial Application of Turmeric (Curcuma longa L.) on Health and Egg Production, in Layers: A Review.

Turmeric (Curcuma longa L.) is a widely recognized spice and medicinal plant that has gained significant attention for its potential health benefits. This review aims to provide a comprehensive overview of the beneficial applications of turmeric in improving health and egg production in layers. The objective of this review is to assess the current scientific literature on the effects of turmeric supplementation in layer diets and evaluate its impact on layer health and egg production. A systematic search was conducted in Google Scholar database to identify relevant studies published in peer-reviewed journals. Studies investigating the effects of turmeric or its bioactive compound curcumin on layer health and egg production were included. Data on various parameters, including immune function, reproductive performance, egg quality and production parameters, were extracted and analysed. Turmeric contains a bioactive compound called curcumin, which possesses antioxidant, anti-inflammatory, antimicrobial and immunomodulatory effects. These properties have been extensively studied and have shown promising results in enhancing layer health and performance. Turmeric supplementation has been reported to improve the overall immune response in layers, reducing the incidence and severity of infectious diseases. It has also been shown to have positive effects on gut health by modulating the gut microbiota composition, improving nutrient absorption and reducing digestive disorders. Furthermore, studies have demonstrated that turmeric supplementation in layer diets can improve egg weight, shell quality, yolk colour and egg production rates. The mechanisms underlying these effects involve the antioxidant properties of turmeric, which protect the reproductive organs, enhance ovarian function and improve reproductive performance. The findings underscore the potential of turmeric as a natural, cost-effective and sustainable intervention for improving layer well-being, egg quality and productivity. However, further research is needed to fully understand the mechanisms of action, optimize dosage regimens and evaluate the long-term effects of turmeric supplementation in layer diets.

Large-scale high purity and brightness structural color generation in layered thin film structures via coupled cavity resonance

Abstract Structural colors, resulting from the interaction of light with nanostructured materials rather than pigments, present a promising avenue for diverse applications ranging from ink-free printing to optical anti-counterfeiting. Achieving structural colors with high purity and brightness over large areas and at low costs is beneficial for many practical applications, but still remains a challenge for current designs. Here, we introduce a novel approach to realizing large-scale structural colors in layered thin film structures that are characterized by both high brightness and purity. Unlike conventional designs relying on single Fabry–Pérot cavity resonance, our method leverages coupled resonance between adjacent cavities to achieve sharp and intense transmission peaks with significantly suppressed sideband intensity. We demonstrate this approach by designing and experimentally validating transmission-type red, green, and blue colors using an Ag/SiO2/Ag/SiO2/Ag configuration on fused silica substrate. The measured spectra exhibit narrow resonant linewidths (full width at half maximum ∼60 nm), high peak efficiencies (>40 %), and well-suppressed sideband intensities (∼0 %). In addition, the generated color can be easily tuned by adjusting the thickness of SiO2 layer, and the associated color gamut coverage shows a wider range than many existing standards. Moreover, the proposed design method is versatile and compatible with various choices of dielectric and metallic layers. For instance, we demonstrate the production of angle-robust structural colors by utilizing high-index Ta2O5 as the dielectric layer. Finally, we showcase a series of printed color images based on the proposed structures. The coupled-cavity-resonance architecture presented here successfully mitigates the trade-off between color brightness and purity in conventional layered thin film structures and provides a novel and cost-effective route towards the realization of large-scale and high-performance structural colors.

Transcriptome analyses of shell color and egg production traits between the uteruses of blue-green eggshell chickens and Hy-Line brown layers

Blue-green eggs exhibit unique shell color; however, compared to commercial layers, blue-green eggshell chickens have lower egg production and lack uniform shell colors. Aiming to confirm the molecular mechanisms that affect shell color and egg production, this study collected the uteruses of 12 blue-green eggshell chickens (BG group) and six Hy-Line layers (Brown group), which had significantly different shell color indexes (SCI) and egg numbers at 300 days of age (EN300). Transcriptome sequencing and comparative analyses were subsequently performed. BG hens were divided into two groups for comparative analysis (BGblue vs. BGgreen and BGlow vs. BGhigh, respectively), based on the differences in SCI and EN300, respectively. The result of weighted gene co-expression network (WGCNA) analysis showed that the sequenced and mapped 16,785 genes were clustered into 18 modules, among which six modules with a total of 4270 genes were highly correlated with SCI and EN300 traits. Five hundred and eleven differentially expressed genes (DEGs) belonged to the six key modules. Through KEGG mapping, GO enrichment, and Cytoscape network analysis, nine Hub genes were tightly associated with SCI and EN300. The up-regulated genes were CCR2, CCR8, CD40LG, IL18RAP, INHBA, and P2RY13, while the down-regulated genes were ABCA13, ADCY2, and GRM1. Co-analyses with the results of comparisons between the BG subgroups revealed that the expression of solute carrier (SLC) proteins and ABC transporters were highly related to eggshell color, while cytokine-cytokine receptor interactions and neuroactive ligand-receptor interactions were key pathways affecting egg production. The expression of extracellular cytokines and membrane receptors were significantly up-regulated in low-yield chickens. The candidate DEGs and pathways found in the study will assist in clarifying the molecular mechanisms affecting shell color and egg production, and improve the breeding of blue-green eggshell chickens.

Continuous flow microfluidic system with magnetic nanoparticles for the spectrophotometric quantification of urea in urine and plasma samples.

Urea, synthesized exclusively in the liver, is primarily transported through the bloodstream to the kidneys, where it is excreted in urine, accounting for 80-90% of nitrogen excretion in humans. Elevated blood urea levels, indicative of kidney dysfunction, make it a crucial biomarker for assessing renal function. Previous studies on urea detection using microdevices have largely focused on conductometric methods. In this study, we demonstrated the application of a continuous flow miniaturized system for rapid spectrophotometric urea quantification using polydimethylsiloxane (PDMS) microdevices. The microdevice featured two distinct zones: an enzymatic reaction zone, where urease-conjugated magnetic nanoparticles were immobilized, and a detection zone, where reagents were incorporated to produce a colored reaction product via a modified Berthelot reaction. Integrating magnetic nanoparticles as a solid support for the enzyme enabled the reuse of PDMS microdevices without compromising the analytical signal. Spectrophotometric detection was performed in an additional microdevice acting as a microflow cell coupled with optical fibers. A calibration curve was constructed using urea standards diluted in phosphate buffer solution (PBS), yielding a linear range of 0.12-3.00 mg dL-1. The method demonstrated detection and quantification limits of 0.04 mg dL-1 and 0.12 mg dL-1, respectively. Precision and accuracy assessments yielded a repeatability of 0.90% and intermediate precision of 4.52%, with recovery rates near 100%. The method was applied to plasma and urine samples, showing urea concentrations within normal physiological ranges and an analysis throughput of 36 measurements per hour.

Bio-Adsorbent for Elimination of Reactive Dye from Aqueous Solution: Kinetic and Statistical Modelling Study

Introduction/Background: The use of various dyes to colour products is a general practice in various industries. The occurrence of these dyes in water, even at small concentrations, is highly noticeable and aesthetically objectionable. In the present study, the applicability of inexpensive and eco-friendly bio-adsorbent has been tested as an alternative substitution of the commercially available activated carbon for the removal of reactive dye from the aqueous solution. Materials and Methods: Bio-adsorbent prepared from pomegranate peel was successfully used to remove the reactive dye (Reactive Black 5) from the aqueous solution. The effects of major parameters such as pH, adsorbent dosage, and contact time on dye removal efficiency were studied. Statistical models were articulated based on selected variables to optimize the decolourisation efficiency of the adsorption process using a full factorial central composite design. Results: Dye removal efficiency of close to 100% was observed at a pH 12 using 1 g adsorbent/ 200 mL dye solution within a contact time of 60 min., yielding a virtually colourless solution. A fixed-bed column study with an initial dye concentration of 100 mg/L at bed depths of 4 cm, 8 cm, and 12 cm yielded a breakthrough time of 300 min, 570 min, and 780 min, respectively. Discussion: Langmuir, Freundlich, and Temkin isotherm models were applied to analyze the sorption equilibrium parameters. The experimental results of the analysis revealed that the Langmuir isotherm fits better than the other isotherms with a linear regression coefficient (R2) of 0.99. The high correlation coefficient (R² > 0.95) and low p-values (< 0.0001) indicate that the model and its terms are significant, making it effective for optimizing operational parameters and accurately predicting the response. Conclusion: The breakthrough curve serves as a tool to evaluate the effectiveness of the prepared adsorbent in real-world applications. The present work not only provides an alternative to commercially available activated carbon for dye wastewater colour removal but also emphasizes the importance of repurposing fruit residues, which could otherwise become environmental pollutants if improperly disposed of.

Analysis of Consumer Behavior in Repeat Purchases of a Product

This study analyzes consumer behavior in repeat purchases of a product, specifically focusing on the case of Light Speed Reborn football and futsal shoes, a locally produced brand in Indonesia. In today's competitive industrial environment, companies strive to cultivate loyal customers, as this loyalty provides a strategic advantage in ensuring future product purchases. The observed phenomenon in this study highlights the repetitive buying behavior of consumers towards Light Speed Reborn shoes, despite only minimal changes in the product's color or design. In Samarinda, these shoes consistently sell out, with many football and futsal players purchasing the same model in different colors. This study employs a qualitative descriptive approach to explore the underlying reasons for this repetitive purchasing behavior, aiming to understand the factors that drive consumer loyalty towards this specific product. Findings indicate that factors such as customer satisfaction, product quality, affordability, comfort, trends, environmental influence, and the strong brand image contribute significantly to the consumers' repeat purchases. The results suggest that brand loyalty and perceived value play crucial roles in fostering repeat purchases of Light Speed Reborn shoes in the Indonesian market.

From Conventional to Craft Beer: Perception, Source, and Production of Beer Color-A Systematic Review and Bibliometric Analysis.

Beer is a popular beverage consumed globally, and studies have emphasized the benefits of moderate consumption as well as its sensory effects on consumers. Color is a crucial sensory attribute, being the first aspect a consumer notices when assessing a beer's quality. This review seeks to offer detailed insights into how brewing methods, raw materials, and the chemical diversity of beer influence the production of beer color. The chemical mechanisms responsible for color development and how consumers and color systems perceive the color of beer were assessed. A systematic review following the PRISMA methodology, coupled with a bibliometric analysis, was performed using (Rayyan 2022) and (VOSviewer 1.6.20) software to assess and evaluate the scientific research retrieved from the Web of Science Core Collection. The findings highlight the significant roles of malt types, heat brewing processes, control of chemical parameters, and innovative brewing techniques in conventional beer color production. Novel chromophores like perlolyrine, pyrrolothiazolate, and furpenthiazinate are thought to affect Pilsen-style beers, along with melanoidins, Strecker aldehydes, and 5-hydroxymethylfurfural (HMF) in conventional beers. In craft beers, such as fruit- or herb-based beers, flavonoids like anthocyanins, along with other natural pigments and synthetic colorants, are identified as the primary sources of color. However, studies related to the influence of chromophores like perlolyrine, pyrrolothiazolate, and furpenthiazinate on beer color are scarce, and emerging additives, such as pigments from microorganisms, spices, exotic herbs, and leaves of plants, on craft beer offer insights for future research.

Salmonella Detection in Food Using a HEK-hTLR5 Reporter Cell-Based Sensor.

The development of a rapid, sensitive, specific method for detecting foodborne pathogens is paramount for supplying safe food to enhance public health safety. Despite the significant improvement in pathogen detection methods, key issues are still associated with rapid methods, such as distinguishing living cells from dead, the pathogenic potential or health risk of the analyte at the time of consumption, the detection limit, and the sample-to-result. Mammalian cell-based assays analyze pathogens' interaction with host cells and are responsive only to live pathogens or active toxins. In this study, a human embryonic kidney (HEK293) cell line expressing Toll-Like Receptor 5 (TLR-5) and chromogenic reporter system (HEK dual hTLR5) was used for the detection of viable Salmonella in a 96-well tissue culture plate. This cell line responds to low concentrations of TLR5 agonist flagellin. Stimulation of TLR5 ligand activates nuclear factor-kB (NF-κB)-linked alkaline phosphatase (AP-1) signaling cascade inducing the production of secreted embryonic alkaline phosphatase (SEAP). With the addition of a ρ-nitrophenyl phosphate as a substrate, a colored end product representing a positive signal is quantified. The assay's specificity was validated with the top 20 Salmonella enterica serovars and 19 non-Salmonella spp. The performance of the assay was also validated with spiked food samples. The total detection time (sample-to-result), including shortened pre-enrichment (4 h) and selective enrichment (4 h) steps with artificially inoculated outbreak-implicated food samples (chicken, peanut kernel, peanut butter, black pepper, mayonnaise, and peach), was 15 h when inoculated at 1-100 CFU/25 g sample. These results show the potential of HEK-DualTM hTLR5 cell-based functional biosensors for the rapid screening of Salmonella.

Smartphone-assisted colorimetric sensor arrays based on nanozymes for high throughput identification of heavy metal ions in salmon

The rapid, precise, and high-throughput identification of multiple heavy metals ions holds immense importance in ensuring food safety and promoting public health. This study presents a novel smartphone-assisted colorimetric sensor array for the rapid and precise detection of multiple heavy metals ions. The sensor array is based on three signal recognition elements (AuPt@Fe-N-C, AuPt@N-C, and Fe-N-C) and the presence of different heavy metal ions affects the nanozymes-chromogenic substrate (TMB) catalytic color production, enabling the differentiation and quantification of various heavy metal ions. Combined with a smartphone-based RGB mode, the colorimetric sensor array can successfully identify five different heavy metal ions (Hg2+, Pb2+, Co2+, Cr6+, and Fe3+) as low as 0.5 μM and different ratios of binary and ternary mixed heavy metal ions in just 5 min. The sensor array successfully tested seawater and salmon samples with a total heavy metal content of 10 μM in the South China Sea (Haikou and Wenchang). Overall, this study highlights the potential of smartphone-assisted colorimetric sensor arrays for the rapid and precise detection of multiple heavy metal ions, which could significantly contribute to food safety and public health monitoring.

Could alternative pathways for carotenoid transformation affect colour production efficiency? A correlative study in wild common crossbills (Loxia curvirostra)

In many vertebrates, dietary yellow carotenoids are enzymatically transformed into 4C-ketocarotenoid pigments, leading to conspicuous red colourations. These colourations may evolve as signals of individual quality under sexual selection. To evolve as signals, they must transmit reliable information benefiting both the receiver and the signaler. Some argue that the reliability of 4C-ketocarotenoid-based colourations is ensured by the tight link between individual quality and mitochondrial metabolism, which is supposedly involved in transforming yellow carotenoids. We studied how a range of carotenoids covary in the feathers and blood plasma of a large number (n > 140) of wild male common crossbills (Loxia curvirostra). Plumage redness was mainly due to 3-hydroxy-echinenone (3HOE). Two other, less abundant, red 4C-ketocarotenoids (astaxanthin and canthaxanthin) could have contributed to feather colour as they are redder pigments. This was demonstrated for astaxanthin but not canthaxanthin, whose feather levels were clearly uncorrelated to colouration. Moreover, moulting crossbills carried more 3HOE and astaxanthin in blood than non-moulting ones, whereas canthaxanthin did not differ. Canthaxanthin and 3HOE can be formed from echinenone, a probable product of dietary β-carotene ketolation. Echinenone could thus be ketolated or hydroxylated to produce canthaxanthin or 3HOE, respectively. In moulting birds, 3HOE blood levels positively correlated to astaxanthin, its product, but negatively to canthaxanthin levels. Redder crossbills also had lower plasma canthaxanthin values. A decrease in hydroxylation relative to ketolation could explain canthaxanthin production. We hypothesize that red colouration could indicate birds' ability to avoid inefficient deviations within the complex enzymatic pathways.

Thermal chemical pretreatment of waste-activated sludge for enhanced solubilization and biogas production: a review

ABSTRACT Waste-activated sludge (WAS) generation is increasing due to the increased generation of wastewater owing to industrialization and urbanization. The disposal of WAS is a significant environmental and financial concern that can be offset by stabilization and valorization via anaerobic digestion (AD). However, the biodegradation is limited due to microbial cells and extracellular polymeric substances (EPS). Physical, chemical, biological, and hybrid pretreatments and the addition of accelerant materials for enhancing direct interspecies electron transfer (DIET) are among the strategies to overcome the poor biodegradation of WAS. Alkaline pretreatment disintegrates the floc structure of WAS by increasing the osmotic pressure, while microwave irradiation has thermal and a-thermal effects and increases the availability of organics for biodegradation. Moreover, the combination of alkaline and thermal pretreatments has synergic effects on solubilization, biogas production, and dewaterability. The disintegration of WAS is recognized by alteration in volatile solid (VS) content, sCOD, BOD/sCOD, turbidity, nutrients solubilization, dewaterability, particle size, specific surface area, change functional group, alteration in microorganism community, microorganism abundance, color, moisture content, lag phase, and biogas production. Higher doses of pretreatment increase COD solubilization but not biodegradable COD. Maximum COD solubilization ranged from 2 to 37% in alkaline, 21 to 260% in the microwave (MW), and 28 to 624% in hybrid pretreatments.

Investigation of genes involved in scent and color production in Rosa damascena Mill

Rosa damascena Mill., commonly known as the King Flower, is a fragrant and important species of the Rosaceae family. It is widely used in the perfumery and pharmaceutical industries. The scent and color of the flowers are significant characteristics of this ornamental plant. This study aimed to investigate the relative expression of MYB1, CCD1, FLS, PAL, CER1, GT1, ANS and PAR genes under two growth stages (S1 and S2) in two morphs. The CCD1 gene pathway is highly correlated with the biosynthesis of volatile compounds. The results showed that the overexpression of MYB1, one of the important transcription factors in the production of fragrance and color, in the Hot pink morph of sample S2 increased the expression of PAR, PAL, FLS, RhGT1, CCD1, ANS, CER1, and GGPPS. The methyl jasmonate (MeJA) stimulant had a positive and cumulative effect on gene expression in most genes, such as FLS in ACC.26 of the S2 sample, RhGT1, MYB1, CCD1, PAR, ANS, CER1, and PAL in ACC.1. To further study, a comprehensive analysis was performed to evaluate the relationship between the principal volatile compounds and colors. Our data suggest that the rose with pink flowers had a higher accumulation content of flavonoids and anthocyanin. To separate essential oil compounds, GC/MS analysis identified 26 compounds in four samples. The highest amount of geraniol, one of the main components of damask rose, was found in the Hot pink flower, 23.54%, under the influence of the MeJA hormone.

Synchronous Bioproduction of Betanin and Mycoprotein in the Engineered Edible Fungus Fusarium venenatum.

Sustainable production of edible microbial proteins and red food colorants is an important demand for future food. Therefore, creation of a chassis strain that can efficiently synthesize both products is extremely necessary and meaningful. To realize this envision, a CRISPR/Cas9-based visual multicopy integration system was successfully developed in Fusarium venenatum. Subsequently, the de novo synthesis of the red food colorant betanin was achieved in the engineered F. venenatum using the above system. After fermentation optimization, the final yields of betanin and mycoprotein reached 1.91 and 9.53 g/L, respectively, when the constant pH naturally decreased from 6 to 4 without the addition of acid after 48 h of fermentation. These results determine a highly suitable chassis strain for the microbial biomanufacturing of betanin, and the obtained engineered strain here is expected to expand the application prospect and improve economic returns of F. venenatum in the field of future food.

Methanol extract of black garlic protects against hyperuricemia by xanthine oxidase inhibitory activity in-vitro

Garlic (Allium sativum L.) has been used as a medicative food for a long time. However, some individuals are averse to raw garlic owing to its pungent taste and aroma. As a result, a variety of garlic formulations have been created to minimize these characteristics without reducing their functions. Extensive in vitro and in vivo research has shown that black garlic has several benefits, including anti-oxidant, anti-inflammatory, anticancer, anti-obesity, anti-diabetic, anti-allergic, cardioprotective, and hepatoprotective characteristics. However, it remains unclear which compounds are active ingredients in the extract and the contributions of the main identified compounds to the extract's XO inhibitory activity are unknown. This study aims to look into the potent XO inhibitors found in black garlic methanol extract. The research methodology is experimental, involving the inhibition of xanthine oxidase activity, specifically measuring the amount of uric acid formed during the reaction catalyzed by xanthine oxidase. This is accomplished in vitro via enzymatic reactions and spectrophotometric measurements. The Maillard reaction is responsible for the production of black color in garlic, and it is influenced by heating temperature, humidity, and fermentation time. Starting on the 17th day of the fermentation process, the brownish intensity of the garlic samples heated at 70 ° C and 90% humidity changed to brown. The optimum concentration is 0.3 units/mL at an optimum temperature of 30oC and an optimum pH of 8.0 at a substratum concentration of 0.30 mM at a wavelength of 284 nm. The activity of the xanthine oxidase enzyme was inhibited by allopurinol at various concentrations, with allopurinol having the highest percentage inhibition value of 78.74 percent at a concentration of 10 ppm. The present study showed that meanwhile, the highest inhibition occurred on the 29th day of fermentation, with a percentage value of 68.01 percent, and decreased the next day

Use of mining effluents for the production of algal-based colorants

In this research, a mining effluent was used to produce microalgal and cyanobacterial biomass to obtain red (carotenoids) and blue pigments (phycocyanin). Two strains were isolated from a hydrothermal source in Norte de Santander and grown in mining wastewater mixed with 50% BG-11 medium for the Osci_UFPS01 cyanobacterium and 50% with Bold Basal medium for the Chlo_UFPS01 microalgae. A carbon, nitrogen, and phosphorus experiment design was developed, and subsequent response surface analysis (RSM) was used to determine the optimal operating conditions for the formation of the products of interest. A notable decrease in pigment production was observed compared to that in the controls without mining wastewater. Overall, 45% of phycocyanin (C PC) per unit dry weight (DW) and 1,129% (w/w) of carotenoids were obtained in the cultures with a mining wastewater mixture in the final optimization processes.

High-transmission dual-tunable structural color based on an all-dielectric medium

In this paper, we propose a three-layer all-dielectric structure capable of dynamic tunability by varying the lattice period and incident angle, thereby facilitating the production of high-quality colors. By integrating three dielectric layers with outer rings and inner cylinders, we effectively suppress multimodal spectra, leading to significantly improved transmission rates for the CMY primary colors. The high transmission efficiency for magenta reaches 96 %, yellow reaches 89 %, and cyan attains an outstanding 99 %. The materials utilized in this design possess characteristics conducive to practical fabrication, thereby offering extensive possibilities for practical applications. Furthermore, our findings provide new insights and potential avenues for future research and applications of structural colors in all-dielectric materials.

Micro-Milli Scale for the Removal of Iron and Copper by a Positively Charged Foam before Nickel Colorimetric Detection using Handy Spectrometer

Introduction: Simple alternative detection of nickel with iron and copper as interferences was proposed. The procedure was based on sampling a milligram sample and a micro-milliliter operation. Methods: The method has been applied to jewelry items. A 50 mg sample was digested by 5 mL of nitric acid with heating. The obtained solution was added with KSCN before passing through polyurethane foam (PUF) (1 cm i.d. × 8 cm length). Some metal ions-SCN complexed (e.g., Fe(III) and Cu(II)) were retained in the column while Ni(II) ions were in the eluate. A 200-500 µL aliquot was added with 4-(2-pyridylazo)-resorcinol (PAR) as the color reagent. At least 30 µL of a portion was measured for the absorbance of the color product using a handy spectrometer. Results: The positively charged foam could remove iron and copper altogether before determining nickel. A standard calibration was a plot of absorbance versus Ni(II) concentration for 1-30 mg/L: absorbance = 0.0123[Ni(II), mg/L] + 0.0435 (R2=0.9945) with a limit of detection (LOD) and limit of quantitation (LOQ) of 0.24 mg/L and 0.81 mg/L, respectively. Two bracelet samples showed the presence of nickel at 0.97 ± 0.25 and 0.27 ± 0.04 mg/g, respectively, and agreed with the reference FlameAAS method. Conclusion: The proposed method could be used to assay nickel in samples containing high levels of iron and copper, such as jewelry. This will benefit general wearers with health concerns associated with nickel, particularly in case of inexpensive accessories. The handy spectrometer used in the study might make be helpful to carry out these studies with a limited tight budget.