A molecular mechanism for bright color variation in parrots.

Purpose This study aims to investigate how the mycelium morphology and the biosynthesis of intracellular and extracellular yellow, orange and red pigments from Monascus purpureus (M. purpureus) were regulated by various initial pH values under liquid fermentation conditions. Design/methodology/approach This study was conducted by cultivating M. purpureus HBSD08 under liquid fermentation media with different initial pH values (from 2.0 to 12.0). Scanning electron microscopy (SEM) was used to observe those mycelium morphology by cultivating at various initial pH values, and those yields of intracellular and extracellular yellow, orange and red pigments, as well as total pigment yields, were measured and calculated. Statistical analysis with p-value less than 0.05 was performed to evaluate the significance of yield differences. Findings The maximum yields of total orange pigment (9.08 ± 0.68 AU·mL−1), total red pigment (11.33 ± 0.49 AU·mL−1), extracellular pigments (24.18 ± 1.90 AU·mL−1) and total pigments (30.28 ± 1.90 AU·mL−1) all occurred at initial pH 5.0. The highest yellow pigment production (14.81 ± 1.60 AU·mL−1) was observed at pH 3.0, while intracellular pigments peaked (14.42 ± 0.48 AU·mL−1) at pH 2.0. At pH 2.0, intracellular orange and red pigment yields increased 3.7- and 2.7-fold, respectively, over pH 3.0, whereas yellow pigment decreased by 75%. Notably, orange and red pigment synthesis exhibited synchronous patterns, at pH 12.0, extracellular pigment yield exceeded that at pH 11.0 by 1.5-fold. Pellet diameter increased then decreased with rising pH, with the most robust morphology at pH 3.0–9.0. Pellets were smallest at pH 2.0 and 12.0. SEM revealed fewer surface particles at pH 2.0, correlating with intracellular pigment accumulation, while pH 12.0 promoted larger surface area and more particles, enhancing extracellular secretion. Originality/value This study systematically elucidates the variation patterns of Monascus pigment biosynthesis and mycelial morphology under different initial pH conditions. The findings demonstrate that extreme initial pH values can effectively steer pigment synthesis toward specific types and spatial distributions (intracellular vs extracellular). Moreover, this work enhances our understanding of the mechanistic role of mycelial morphology in pigment biosynthesis, offering a novel strategy for targeted pigment production.

The development of stable and reproducible inorganic pigments is noteworthy for industrial applications mainly considering more intense shades and low toxicity. Among the various candidates to substitute non‐hazardous red and yellow pigments, CeO 2 and CeO 2 :Pr have been attracting attention because of their opacity and high‐temperature stability besides being environmental‐friendly and health‐friendly. In this study, nanostructured CeO 2 and CeO 2 :Pr samples were synthesized using the polymeric precursor method and structural and optical characterizations were performed. Scanning electron microscopy reveals the morphology of CeO 2 nanoparticles in which the particle size ranges from 22 to 28 nm as a function of the annealing temperature. Pr‐doping does not show influence on the particle size. XRD results show that CeO 2 and CeO 2 :Pr samples crystallize in the cubic fluorite lattice with Fm 3 m space group. Raman spectra show the fluorite F 2g mode, confirming the XRD results. With Pr‐doping and the annealing of the samples, two bands are observed between 550 and 600 cm −1 , which are related to the defects in the fluorite structure associated with oxygen vacancies. XPS spectra reveal an increase in the ratio of Ce 3+ ions depending on the annealing temperature and Pr‐doping. This increase is associated with the carbon removal from the lattice by annealing. This behavior causes a change in the hue of the powders as the annealing temperature increases. According to diffuse reflectance and colorimetric measurements, CeO 2 shows a light‐yellow color due to the O 2p­Ce 4f transitions whose b* parameter mainly decreases with annealing, becoming almost white. The CeO 2 :Pr sample exhibits a red‐orange color because of the electronic transitions between 4f 2 → 5d 1 states of Pr 3+ . Upon annealing, L* and b* parameters decrease, resulting in a red‐brown shade. The charge compensation or charge transfer is responsible for the modification of the hue of these pigments.

Objective: The objective of this work was the production of red and yellow pigments by the fungus Monascus purpureus NRRL 1596 using agroindustrial wastes of the cassava production chain. Methods: Solid state fermentation experiments were carried out by using cassava peels and cassava wastewater as substrate for pigment production by Monascus purpureus NRRL 1596. Initial moisture content and the addition of soy bran to improve Carbon/nitrogen ratio were optimized in order to follow the growth kinetics and pigment production in the selected substrate. Total sugars, biomass, pigments, pH and moisture content were analysed. Results: Initial moisture content of 75% and 1g.L-1 of nitrogen were determined as optimal for pigment production after optimization studies. The highest pigment concentration was reached in 8 days of fermentation for red pigments, absorbance of 5.4 for the 500 nm range and in 4 days for yellow pigments absorbance of 8.7 for 410 nm. The maximal growth rate (13.37 g/100 g of protein) was reached at 8 days of fermentation coinciding with the highest red pigment concentration. Antimicrobial activity of the pigment produced were performed. Conclusion: It was observed that the association of cassava by-products are an alternative for the production of red and yellow pigments of the fungus Monascus purpureus NRRL1596.

Ultrasound-assisted one-step extraction of safflower red and yellow pigments by natural ternary deep eutectic solvents: Extraction optimization and mechanism, separation and biological activities of pigments.

The lengthy time periods required by current spalting methods prohibit the economically viable commercialization of spalted wood on a large scale. This work aimed to compare the effects of induced spalting in 16 Pacific Northwest woods using three common spalting fungi, Chlorociboria aeruginosa, Scytalidium cuboideum, and Scytalidium ganodermophthorum, with the significantly less time-consuming treatment of these woods using dichloromethane-extracted green, red, and yellow pigments from the same fungi. For pigment extracts, the dosage required for a pigment to internally color various wood species to 30% internal coverage was investigated. With few exceptions, treatment with pigment extracts outperformed induced spalting in terms of percent internal color coverage. Cottonwood consistently performed best with all three pigment solutions, although chinkapin performed as well as cottonwood with the red pigment, and Port Orford cedar performed as well with the yellow pigment. While no wood species showed 30% internal color coverage with the green pigment solution, a number of additional species, including pacific silver fir, madrone, dogwood, and mountain hemlock showed internal color coverage on the order of 20–30% for red and/or yellow. Cottonwood was determined to be the best suited wood species for this type of spalting application.

A factorial experiment in a randomised complete block design with three replications was conducted to study the effect of harvest time of florets of spring safflower varieties on the amount of red (carthamin) and yellow (carthamidin) pigments in the petals. The first factor was the variety of safflower (MEC88, MEC59, Goldasht, Zendehrood, Sina) and the second factor was harvest time of florets (onset of flowering, after pollination at onset of petal wilting). The results showed that, at the onset of flowering, spring safflower varieties showed the highest yield of florets and MEC59, MEC88, Zendehrood and Sina showed good yield of florets. Harvest time affected the amount of carthamin and carthamidin; florets produced more carthamidin at the beginning of flowering and the amount of carthamidin decreased during flower development, while the amount of carthamin increased. The effect of cultivars was significant. To get the highest level of carthamidin, Zendehrood should be harvested at the onset of flowering. If carthamin is needed, Zendehrood should be harvested immediately after pollination, at the onset of petal wilting.

Determination of the influence of surface coating and particle size on flow properties of organic pigment powders

Production of Monascus pigments by a solid-liquid state culture method

Colorants are component that is commonly added to many kinds of product, including food products. Regardless of its effectiveness and lower price, the effects of synthetic colorants towards human’s health become a challenge for food colorant industries. Production of natural food colorant using microorganism as the producing agent is a promising prospect because microorganism has a high growth rate. Monascus purpureus can produce a set of natural pigments consist of yellow (monascin and ankaflavin), orange (rubropunctatin and monascorubrin) and red (rubropunctamine and monascorubramine) pigment. The objective of this research is to optimize the micronutrient composition in the medium for the production of Monascus pigment through solid-state fermentation using the job’s tears (Coix lacryma-jobi L) as the substrate. Response surface method (RSM) was used to optimize the concentration of four substrate components: MSG, NaCl, KH2PO4, and MgSO4. From the experiment, it was found that the maximum red pigment was produced in medium with additional of (w/w): MSG 1.496%, NaCl 1.0%, KH2PO4 3.515% and MgSO4 0.206%. The yellow pigment was maximally produced in medium with additional of (w/w): MSG 1.5%, NaCl 1.0%, KH2PO4 2% and MgSO4 0.2%. Biomass was maximally produced in the medium with additional of (w/w): MSG 1.41%, NaCl 1.01%, KH2PO4 5.0% and MgSO4 0.2%. Among those nutrients, MSG gave the biggest impact on the increasing of pigment and biomass production.

Gastric cancer (GC) is a common malignant tumor worldwide, characterized by complex biological processes. The distribution of various cell types and gene expression profiles in the GC microenvironment remains unclear. This study uses single-cell RNA sequencing to explore gene expression patterns and identify differentially expressed genes in GC samples, offering new insights into cellular diversity and potential molecular mechanisms. We conducted temporal and clustering analyses with single-cell sequencing, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to clarify their functions. Using machine learning, we identified relevant genes to create highly accurate prediction models. Additionally, ssGSEA analysis provided detailed insights into the immunosuppressive tumor microenvironment, revealing complex gene expression interactions and diverse immune infiltrates in cancer. Correlation analysis highlighted TIMP1 as having significant prognostic value across different immune cell subtypes. Single-cell RNA sequencing revealed the cellular landscape and gene expression profiles of the GC microenvironment, offering crucial data on how cell heterogeneity is regulated in relation to the tumor microenvironment. Moreover, new insights into the expression levels of AGT, INHBA, and TIMP1 showed distinct sex-biased gene functions within the tumor microenvironment. These findings enhance our understanding of the molecular mechanisms associated with gastric cancer development and may lay the groundwork for identifying novel therapeutic targets and diagnostic strategies.

The accumulation of soil on photovoltaic (PV) modules may introduce a spectral loss due to the color profile of the accumulated material. In order to compare the spectral and total losses experienced by a cell, soil analogs were formulated to contain common mineral pigments (Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> and göthite) with previously developed “standard grime” mixtures. These mixtures simulated a wide range of desert soil colors and were applied to glass test coupons. The light transmission through the deposited film was evaluated by UV/vis/NIR spectroscopy and by placing the coupon over a test cell in a 1-sun simulator and quantum efficiency test stand. Distinct peaks in the 300-600-nm range were observed by UV/vis/NIR spectroscopy corresponding to the Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> and göthite. Approximately analogous features were noted in the QE measurement. Overall comparisons were made by integrating the response of a soiled coupon relative to a clean reference. Soils rich in red pigments (Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) caused a greater integrated response than soils rich in yellow pigment (göthite). The yellow soils caused a greater attenuation in a specific region of the spectrum (300-450 nm), which may have significant implications to specific devices, such as multijunction and CdTe technologies.

The avian plumage color gamut is the complete range of plumage colors, as seen by birds themselves. We used a tetrahedral avian color stimulus space to estimate the avian plumage color gamut from a taxonomically diverse sample of 965 plumage patches from 111 avian species. Our sample represented all known types of plumage coloration mechanisms. The diversity of avian plumage colors occupies only a portion (26–30%, using violet-sensitive and ultraviolet-sensitive models, respectively) of the total available avian color space, which represents all colors birds can theoretically see and discriminate. For comparison, we also analyzed 2350 plant colors, including an expansive set of flowers. Bird plumages have evolved away from brown bark and green leaf backgrounds and have achieved some striking colors unattainable by flowers. Feather colors form discrete hue ‘‘continents,’’ leaving vast regions of avian color space unoccupied. We explore several possibilities for these unoccupied hue regions. Some plumage colors may be difficult or impossible to make (constrained by physiological and physical mechanisms), whereas others may be disadvantageous or unattractive (constrained by natural and sexual selection). The plumage gamut of early lineages of living birds was probably small and dominated by melanin-based colors. Over evolutionary time, novel coloration mechanisms allowed plumages to colonize unexplored regions of color space. Pigmentary innovations evolved to broaden the gamut of possible communication signals. Furthermore, the independent origins of structural coloration in many lineages enabled evolutionary expansions into places unreachable by pigmentary mechanisms alone. Key words: bird vision, flower, gamut, morphospace, plumage, structural color, tetrahedral color space. [Behav Ecol]

BackgroundRenal fibrosis, characterized by the abnormal accumulation of extracellular matrix in renal tissue and progressive loss of kidney function, is posing a significant challenge in clinical treatment. While several therapeutic options exist, effective treatments remain limited. Inonotus obliquus (Chaga), a traditional medicinal mushroom, has shown promising effects in chronic kidney disease (CKD), yet its cellular and molecular mechanisms remain largely unexplored.MethodsWe analysed the chemical composition of Chaga using UPLC-MS and predicted its biological targets using PubChem and Swiss Target Prediction. We used single-cell RNA sequencing to study cellular responses in a mouse model of folic acid-induced renal fibrosis, complemented by spatial transcriptomics to map cellular location patterns. Histological assessment was performed using H&E and Masson trichrome staining.ResultsFor the first time, we employed single-cell RNA sequencing technology to investigate Chaga treatment in renal fibrosis. Histological analysis revealed that Chaga treatment significantly reduced renal tubular damage scores [from 5.00 (5.00, 5.00) to 2.00 (2.00, 2.00), p < 0.05] and decreased collagen deposition area (from 11.40% ± 3.01% to 4.06% ± 0.45%, p < 0.05) at day 14. Through analysis of 82,496 kidney cells, we identified 30 distinct cell clusters classified into eight cell types. Key findings include the downregulation of pro-inflammatory M1 macrophages and upregulation of anti-inflammatory M2 macrophages, alongside decreased T cell responses. Single-cell sequencing revealed differential gene expression in proximal tubular subpopulations associated with reduced fibrosis. Pathway and network pharmacology analyses of 60 identified compounds in Chaga and their 675 predicted targets suggested potential effects on immune and fibrotic pathways, particularly affecting Tregs and NKT cells. Cell-to-cell communication analyses revealed potential interactions between proximal tubular cells, macrophages, and T Cells, providing insights into possible mechanisms by which Chaga may ameliorate renal fibrosis.ConclusionOur study provided new insights into the potential therapeutic effects of Chaga in renal fibrosis through single-cell sequencing analysis. Our findings suggest that Chaga may represent a promising candidate for renal fibrosis treatment, though further experimental validation is needed to establish its clinical application.

As in many sexually dichromatic species in which males are brightly colored, female House Finches (Carpodacus mexicanus) show a subdued expression of the same coloration as males. I quantified the carotenoid plumage coloration of females from the subspecies C. m. frontalis in Michigan, New York, Hawaii Island, and two sites in California, and from the subspecies C. m. griscomi in Guerrero, Mexico. The proportion of females with detectable carotenoid pigmentation differed significantly among populations, as did the median plumage brightness of colorful females. In Michigan, but not California, yearling females tended to be more colorful than older females. Among C. m. frontalis populations, there was a significant positive correlation between the plumage brightness of females and males, but in the C. m. griscomi population males were brightly colored while females were drab. In aviary experiments, females of all ages and from all populations converged on a similar plumage brightness after molt when fed a common diet. Moreover, females from all populations showed maximum color expression when provided with abundant red carotenoid pigments. These observations suggest that local and regional variation in the plumage brightness of females reflects local and regional variation in the availability of dietary carotenoid pigments and that female House Finches do not actively forage for carotenoids.

Efficient synthesis of analogs of safflower yellow B, carthamin, and its precursor: two yellow and one red dimeric pigments in safflower petals