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The phytochemical study of the Diaporthe species has revealed significant classes of mycotoxins and phomopsins. Dihydroanthracenone derivatives, chromanones and isochromophilones have also been isolated from Diaporthe sp. These findings led us to explore the Diaporthe perseae for phytochemical analysis that resulted in the isolation of four new compounds designated as isochromophilones H-K (1-4), alongside three previously identified metabolites. Using extensive spectroscopic investigations such as NMR, and Mass spectroscopy, their structures were elucidated. Furthermore, the antimicrobial and anti-diabetic potentials of all isolated compounds were assessed. Compounds 1-3 demonstrated significant antibacterial activity, while compounds 4-7 exhibited comparatively lower effectiveness than the reference antibiotics. Compounds 2-3 showed potent diabetic inhibition, displaying IC 50 values of 16.3 ± 0.3 and 25.4 ± 0.3, respectively. Compounds 1, 5, and 6 displayed mild anti-diabetic effects, with IC 50 values of 56.5 ± 0.8, 37.6 ± 0.4, and 48.2 ± 0.6. However, compounds 4 and 7 were found least active., Competing Interests: Declaration of competing interest The author has no conflict of interest exits in the submission of this manuscript and the authors have complied with journal ethical requirements. Moreover, manuscript is approved by all authors as well as all the authorities acknowledged for publication., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Natural pigments are becoming more significant because of the rising cost of raw materials, pollution, and the complexity of synthetic pigments. Compared to synthetic pigments, natural pigments exhibit antimicrobial properties and is less allergic. Pigments from microbial sources could easily be obtained in an inexpensive culture media, produced in high yields, and microbes are capable of producing different colored pigments. Searching for new sources for natural pigments to replace synthetic ones in food applications has become an urgent necessity, but the instability of these compounds is sometimes considered one of the obstacles that reduce their application. Encapsulation provides an ideal solution for natural dye protection through a controlled release strategy. Thus, this study aims at isolation of several soil fungi and subsequent screening their pigment production ability. The chosen pigment-producing fungal strain underwent full identification. The produced pigment was extracted with ethyl acetate and estimated spectrophotometrically. As there is a necessity to obtain a high pigment yield for efficient industrial application, the best production medium was tested, optimum conditions for maximum dye production were also investigated through the response surface methodology, and gamma irradiation was also employed to enhance the fungal productivity. Encapsulation of the produced pigment into chitosan microsphere was tested. The pigment release under different pH conditions was also investigated., Results: A new strain, Fusarium verticillioides AUMC 15934 was chosen and identified for a violet pigment production process. Out of four different media studied, the tested strain grew well on potato dextrose broth medium. Optimum conditions are initial medium pH 8, 25 °C-incubation temperature, and for 15-day incubation period under shaking state. Moreover, a 400 Gy irradiation dose enhanced the pigment production. Chitosan microsphere loaded by the pigment was successfully prepared and characterized by infrared spectroscopy and scanning electron microscopy., Conclusion: This irradiated Fusarium strain provides a more economically favorable source for production of a natural violet dye with an optimum productivity, enhanced yield, and improved properties (such as, enhanced stability, controlled release, and bioaccessibility) by encapsulation with chitosan for efficient application in food industry., (© 2024. The Author(s).)

The aim of this study was to obtain extracts of anthocyanin pigments from red and purple-fleshed potato juices characterized by stable color. For this purpose, potato juices were pasteurized at different temperatures or fruit and vegetable concentrates were added to them. Color stability tests of the obtained pigments were carried out in model pH and temperature conditions and after adding to natural yogurt. Both the pasteurization process and the addition of fruit and vegetable concentrates to the potato juices positively affected their color and its stability in time. However, the pasteurization of the potato juices had a negative effect on the content of biologically active compounds, in contrast to the juices stabilized with the addition of fruit and vegetable concentrates. Anthocyanin pigments from red-fleshed potato juices were more stable than those isolated from the purple-fleshed potato juices. The results of model tests of the anthocyanin pigment concentrates from the colored-flesh potatoes and natural yoghurts with their addition confirmed the high stability of the tested concentrates.

This study emphasizes the significance of optimizing salt content during the fermentation of red beetroot to produce healthier and high-quality fermented products. It investigates the impact of different salt levels on fermentation, analyzing various parameters such as pH levels, dry matter content, total acidity, salt content, color changes, pigment content, and lactic acid bacteria count. This study identifies the most favorable salt concentration for bacterial growth during fermentation and storage as 2-3%. It was evaluated that salt levels fluctuated significantly during fermentation, with nearly 50% of the added salt absorbed by the beetroot tissues, mainly when lower salt concentrations were used. The fermentation process had a negative effect on the content of betalain pigments, as well as yellow pigments, including vulgaxanthin-I. It was also found that fermentation and storage affected the proportions of red pigments, with betacyanins proving to be more stable than betaxanthins, and that salt addition affected negatively pH and total acidity while causing an increase in yellow color. The pH was negatively correlated with the duration of the process, the amount of red pigment, and bacterial count. The results indicate that lower salt levels can lead to favorable physicochemical and microbiological parameters, allowing for the production of fermented red beetroot with reduced salt content without compromising quality.

A color-deepening effect of theaflavins on the theanine-glucose thermal reaction model was revealed. Generated chromogenic intermediates in the initial stage and an accelerated browning rate through the promoted degradation of theanine-glucose Amadori rearrangement product in the intermediate and final stages are responsible for the color-deepening effect. Four pink-to-red theaflavin-theanine intermediates were verified as theaflavinies referencing the nuclear magnetic resonance and liquid chromatography-mass spectrometry information on theaflavins and l-theanine, including one accurately identified as theaflavinie 4. Theaflavinie 4 showed two maximum absorption peaks at 401 and 506 nm with parallel intensities, which resulted in a significant dichromic color change from pale pink to orange and red. Theaflavinies also could undergo further thermal reactions to yield brown polymers under higher temperatures (130 and 140 °C). This research provided new insight into realizing thermally formed polymers during black tea processing, which may be formed by oxidation products and amino acids or proteins through non-enzymatic thermal reactions.

Bostrycoidin is one of the pigments produced by the Fusarium genus of fungi. On the one hand, it has significant pharmacological importance, while on the other hand, it serves as a presence marker of Fusarium infection in useful grain crops, fruits, and soils. In this regard, the structural and optical properties of the bostrycoidin molecule were studied in the framework of density functional theory (DFT). The most stable geometry as well as higher-energy conformers and tautomers were investigated. The lowest-energy tautomer was found to be about 3 kcal/mol higher in energy than the most stable structure, resulting in relatively low population of this state. The obtained conformational rotamers associated with the rotation of the OMe group possess similar energy. The vibrational spectrum was modeled for the most stable conformer, and the most active peaks in the IR absorbance spectrum were assigned. Moreover, the electronic absorption spectrum was simulated within the time-dependent DFT approach. The obtained theoretical spectrum is in good agreement with the experimental data and the theoretically calculated longest-wavelength transition (HOMO-LUMO) was about 498 nm.

Cefadroxil is a widely used antibiotic with a low elimination efficiency in wastewater treatments plants, so it represents a contaminants of emerging concern that should be removed. The photosensitization process that involves natural pigments and visible sunlight can be offered as an environmentally friendly alternative to be considered for Cefadroxil degradation. In this investigation, we carried out a mechanistic and kinetic approach to Cefadroxil photodegradation sensitized by Riboflavin and Humic Acid, in individual and combined processes. Our experiments indicate that Cefadroxil is able to interact with the excited states of Riboflavin as well as with the photogenerated reactive oxygen species, with an important contribution of singlet oxygen. The antibiotic was less sensitive to the photodegradation in the presence of Humic Acids and in the mixture of Riboflavin and Humic Acids. Self-sensitization processes and internal filter effects are proposed as possible explanations for the observed phenomenon. The reaction between Cefadroxil and singlet oxygen showed a dependence with the pH of the medium, the photodegradation kinetic constants are greater at alkaline pH compared to neutral pH. The reaction is favored when the anionic species of the antibiotic is present. Microbiological tests on S. aureus indicated that the antibiotic reduce its antimicrobial activity as a consequence of the photooxidative process mediated by singlet oxygen. We believe that the results are relevant since, the sensitized photodegradation process could lead to the oxidation of Cefadroxil and to the progressive loss of its antimicrobial function, this fact could contribute to the decrease in the generation of bacterial multi-resistance to antibiotics in the environment., (© 2024. The Author(s), under exclusive licence to the European Photochemistry Association, European Society for Photobiology.)

Red Monascus Pigment (RMP), a natural pigment, has attracted significant attention due to its suitability for food use and potential health benefits. However, preserving its stability and exploring value-added development opportunities remain crucial challenges. This study outlined the utilization of RMP, by successfully preparing hydrogel beads encapsulating RMP crude extract (RMPCE) through Ca 2+ -mediated chitosan (CS)/sodium alginate (SA) encapsulation (CO-RMPHB). A systematic investigation into the fabrication and stability parameters, including preparation conditions, temperature, monochromatic light and storage time, was undertaken. Through optimization (SA: 2.50 wt%; CaCl 2 : 6.00 wt%; CS: 0.50 wt%), maximum encapsulation efficiency of 73.54 ± 2.16 % was achieved. The maximum swelling degree of blank hydrogel beads (BHB) in simulated gastric solution (pH = 1.2, 1.50 ± 0.97 %) was significantly lower than in simulated intestinal solution (pH = 7.0, 28.05 ± 1.43 %), confirming their sensitivity to pH changes. Additionally, the CO-RMPHB (66.08 %, 1000 μL) exhibited superior DPPH radical scavenging capability compared to individual RMPCE or BHB. Furthermore, analysis of the release kinetics based on zero-order, first-order, Higuchi, and Ritger-Peppas models revealed that RMPCE release from CO-RMPHB under in vitro digestion models followed non-Fickian diffusion. This discovery effectively addresses the challenges of the stability and controlled release of RMP, expanding its applications in the food and pharmaceutical industries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Antimicrobial resistance has emerged as a major global health threat, necessitating the urgent development of new antimicrobials through innovative methods to combat the rising prevalence of resistant microbes. With this view, we developed three novel nanoconjugates using microbial natural pigment for effective application against certain pathogenic microbes., Results: A natural red pigment (RP) extracted from the endophyte Monascus ruber and gamma rays were applied to synthesize RP-ZnO, RP-CuO, and RP-MgO nanoconjugates. The synthesized nanoconjugates were characterized by different techniques to study their properties. The antimicrobial potential of these nanoconjugates was evaluated. Moreover, the antibiofilm, protein leakage, growth curve, and UV light irradiation effect of the synthesized nanoconjugates were also studied. Our results confirmed the nano-size, shape, and stability of the prepared conjugates. RP-ZnO, RP-CuO, and RP-MgO nanoconjugates showed broad antimicrobial potential against the tested bacterial and fungal pathogens. Furthermore, the RP-ZnO nanoconjugate possessed the highest activity, followed by the RP-CuO against the tested microbes. The highest % inhibition of biofilm formation by the RP-ZnO nanoconjugate. Membrane leakage of E. coli and S. aureus by RP-ZnO nanoconjugate was more effective than RP-MgO and RP-CuO nanoconjugates. Finally, UV light irradiation intensified the antibiotic action of the three nanoconjugates and RP-ZnO potential was greater than that of the RP-MgO, and RP-CuO nanoconjugates., Conclusion: These findings pave the way for exploiting the synthesized nanoconjugates as potential materials in biomedical applications, promoting natural, green, and eco-friendly approaches., (© 2024. The Author(s).)

Total syntheses of borolithochromes H1, H2, I1, and I2, the red pigments isolated from fossils of Jurassic putative red alga Solenopora jurassica, have been achieved. The naphthoquinone possessing a chiral sec-butyl side chain has been synthesized from (S)-2-methylbutanol. The Diels-Alder reaction of the chiral naphthoquinone and the previously reported diene was followed by one pot S-methylation/intramolecular Corey-Chaykovsky reaction/epoxide rearrangement to provide the benzo[gh]tetraphene skeleton. Complexation of the resulting ligand with trimethyl borate and the following O-demethylation furnished a 1:1 mixture of borolithochromes I1 and I2, which were separated by HPLC using CHIRALPAK IC® to afford optically pure borolithochromes I1 (6) and I2 (7). On the other hand, borolithochromes H1 and H2 were not separated by HPLC in our laboratory. Fortunately, the mixture of the methyl ethers of borolithochromes H1 and H2 were separated and O-demethylation with magnesium iodide furnished optically pure borolithochromes H1 (4) and H2 (5)., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

The newly recorded Phyllymenia gibesii in the Mediterranean Sea at Alexandria coast of Egypt is regarded as a significant source of bioactive substances and is applied as an antioxidant, anti-inflammatory, and antimicrobial agent. According to the HPLC chromatograms, the acetone extract of P. gibesii comprised ten photosynthetic pigments (chlorophyll-a, chlorophyll-d, α-carotene, β-carotene, phycocyanin, allophycocyanin, antheraxanthin, β-cryptoxanthin, lutein, and violaxanthin). Total carotenoids were the dominant class in the pigments' profile, achieving a concentration of 257 g/g dry weight. The P. gibbesii extract had a total content of phenols (146.67 mg/g) and a total content of flavonoids (104.40 mg/g). The capacity of all the investigated biological activities augmented with the concentration of the algal extract. The maximal DPPH scavenging capacity was 81.44%, with an inhibitory concentration (IC 50 ) of 9.88 μg/mL. Additionally, the highest ABTS scavenging capacity was 89.62%, recording an IC 50 of 21.77 μg/mL. The hemolytic activity of P. gibbesii attained a maximum capacity of 49.88% with an IC 50 of 100.25 μg/mL. Data also showed the maximum anti-inflammatory effectiveness at 81.25%, with an IC 50 of 99.75 μg/mL. Furthermore, the extract exhibited antimicrobial capacity against all reference strains, particularly at high concentrations (0.1 mg/mL), with the greatest effect on C. albicans and E. coli., (© 2024. The Author(s).)

A unique family of decarboxylated betalains derived from dopamine has recently been discovered. Due to the lack of chemical standards, the existence and distribution of decarboxylated betalains in nature remain unknown. Traditional betalains contain L-dihydroxyphenylalanine as the starting point of the biosynthetic pathway and betalamic acid as a structural and functional unit, while the recently discovered betalains rely on dopamine. Here, 30 dopamine-derived betalains were biotechnologically produced, purified, and characterized, creating an unprecedented library to explore their properties and presence in nature. The maximum absorbance wavelengths for the pigments ranged between 461 and 485 nm. HPLC analysis showed retention times between 0.6 and 2.2 min higher than traditional betalains due to their higher hydrophobicity. The presence of decarboxybetalains in nature was screened using HPLC-ESI-Q-TOF mass spectrometry in various species of the Amaranthaceae family: beetroot (Beta vulgaris subsp. vulgaris), Swiss chard (B. vulgaris var. cicla), celosia (Celosia argentea var. plumosa), and quinoa (Chenopodium quinoa). The latter species had the highest content of decarboxybetalains (28 compounds in its POEQ-143 variety). Twenty-nine pigments were found distributed among the different analyzed plant sources. The abundance of decarboxybetalains demonstrated in this work highlights these pigments as an important family of phytochemicals in the order Caryophyllales., Competing Interests: Conflict of interest statement. Some of the authors launched in 2022 the company Betaelegans Biotech, a spin-off from the public academic institution Universidad de Murcia (Spain), primarily devoted to the synthesis of betalain standards. This has not biased or influenced the conception, analysis, or writing of the present research. The authors declare no other competing financial interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

Boiled lotus rhizome discs (BLRDs), as common processed products of lotus rhizome, have gained increasing attention from consumers and food manufacturers. However, the blue pigment formed during boiling affects its appearance and reduces the appetite of BLRDs. In this study, the effects of polyphenols and iron contents on blue pigment formation in BLRDs in different regions and months were investigated. Results revealed that blue variation was more serious in March and April of the second year in Wuhan, and polyphenols and iron contents in these two months were significantly higher than those in other months. Then, UPLC and UV-Vis analysis showed that polyphenols causing the formation of blue pigment in BLRDs were L-dopa, gallocatechin, catechin, epigallocatechin, chlorogenic acid and epicatechin, among which L-dopa (52.450 mg/100 g in fresh lotus rhizome (FLR)) and gallocatechin (36.210 mg/100 g in FLR) possessed the greatest effect. Moreover, the ESI-Q-TOF-MS analysis of L-dopa-iron chelate and gallocatechin-iron chelate suggested that the blue pigment of BLRDs was mainly in the form of bis-complexes under boiling conditions. The study on formation mechanism of blue pigment in BLRDs can provide a reference for lotus rhizome processing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Monascus pigment (MP) is a natural food coloring with vital physiological functions but prone to degradation and color fading under light conditions., Results: This study investigated the effect of complex formation of soybean protein isolate (SPI), maltodextrin (MD), and MP on the photostability of MP. Light stability was assessed through retention rate and color difference. Fluorescence spectroscopy (FS), circular dichroism (CD), Fourier-transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) explored MP, SPI, and MD interactions, clarifying the MP-SPI-MD complex mechanism on the light stability of MP. Microstructure and differential scanning calorimetry (DSC) analyzed the morphology and thermal properties. The retention rate of MP increased to approximately 80%, and minimal color difference was observed when adding SPI and MD simultaneously. FS revealed hydrophobic interaction between MP and SPI. FTIR analysis showed intensity changes and peak shifts in amide I band and amide II band, which proved the hydrophobic interaction. CD showed a decrease in α-helix content and an increase in β-sheet content after complex formation, indicating strengthened hydrogen bonding interactions. Scanning electron microscopy (SEM) analysis demonstrated that MP was attached to the surface and interior of complexes. XRD showed MP as crystalline, while SPI and MD were amorphous, complexes exhibited weakened or absent peaks, suggesting MP encapsulation. The results of DSC were consistent with XRD., Conclusion: SPI and MD enveloped MP through hydrogen bonding and hydrophobic interaction, ultimately enhancing its light stability and providing insights for pigment-protein-polysaccharide interactions and improving pigment stability in the food industry. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

As food packaging evolves, consumer interests are shifting from traditional to intelligent food packaging systems. Intelligent packaging includes active components that display changes in a visual or interactive form perceivable by consumers. This offers real-time monitoring of the quality and shelf life of the packaged food and enhances transparency. For example, pH-sensitive natural pigment-based films change color in response to variations in pH levels, enabling the film/labels to reflect alterations in the acidity or basicity of the food inside the package. Natural pigments like anthocyanins, curcumin, betalains, chlorophyll, and carotenoids have been comprehensively reported for developing biodegradable pH-sensitive films of starch, protein, chitosan, and cellulose. Natural pigments offer great compatibility with these biopolymers and improve the other performance parameters of the films. However, these films still lack the strength and versatility of petroleum-based synthetic plastic films. But these films can be used as an indicator and combined with primary packaging to monitor freshness, time-temperature, and leak for muscle foods, dairy products, fruits and vegetables, and bakery products. Therefore, this review provides a detailed overview of pH-sensitive pigments, their compatibility with natural polymers, their role in film performance in monitoring, and their food packaging applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microorganisms are known to be a promising source of biopigments because they are easy to obtain, can be produced on a commercial scale, and are environmentally friendly. Therefore, the aim of this work was to characterize a brown pigment (BP) produced by HM053 in NFbHPN-lactate medium. The BP was extracted from the pellet (BPP) or supernatant (BPS), in the presence (BPPTrp, BPSTrp) or absence (BPPw, BPSw) of tryptophan (Trp). The UV-vis results were similar among all BP samples and compared with commercial melanin used as a standard, and the maximum absorption was observed around 200-220 nm. FTIR spectra showed that BP and commercial melanin had slight differences, with a small band between 3000-2840 cm - 1 , related to C-H in the CH 2 and CH 3 aliphatic groups, which is not observed in the commercial melanin. Between BPP and BPS showed a different structure with bands in the region 1230-1070 cm - 1 related to groups C-O. The thermogravimetric curves for BPSw and BPSTrp showed similar behavior, with 4 stages of mass loss. The similarity between BPPw and BPPTrp with 2 stages of mass loss was also observed. Scanning electron microscopy results showed morphological differences between BPP and BPS, where BPP had a physical structure more homogeneous and a regular flat surface, while the BPS physical structure did not seem homogeneous and the surface was uneven with some spherical structures as commercial melanin., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Natural pigments are increasingly favored in the food industry for their vibrant colors, fewer side effects and potential health benefits compared to synthetic pigments. However, their application in food industry is hindered by their instability under harsh environmental conditions. This review evaluates current strategies aimed at enhancing the stability and bioactivity of natural pigments. Advanced physicochemical methods have shown promise in enhancing the stability of natural pigments, enabling their incorporation into food products to enhance sensory attributes, texture, and bioactive properties. Moreover, recent studies demonstrated that most natural pigments offer health benefits. Importantly, they have been found to positively influence gut microbiota, in particular their regulation of the beneficial and harmful flora of the gut microbiome, the reduction of ecological dysbiosis through changes in the composition of the gut microbiome, and the alleviation of systemic inflammation caused by a high-fat diet in mice, suggesting a beneficial role in dietary interventions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The intricate composition of microalgal pigments plays a crucial role in various biological processes, from photosynthesis to biomarker identification. Traditional pigment analysis methods involve complex extraction techniques, posing challenges in maintaining analyte integrity. In this study, we employ Electron Transfer Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry (ET-MALDI-MS) to compare the pigmentary profiles of Chlorella vulgaris intact cells, chloroplasts, and solvent extracts. We aim to obtain comprehensive extracts rich in polar and non-polar compounds using ultrasound-assisted and supercritical fluid extraction methods. Additionally, intact chloroplasts are isolated using a lysis buffer and sucrose density gradient centrifugation. Our ET-MALDI-MS analysis reveals distinct compositional differences, highlighting the impact of extraction protocols on microalgal pigment identification. We observe prominent signals corresponding to radical cations of key pigments, including chlorophylls and carotenoids, which are crucial for C. vulgaris identification. Furthermore, ET-MALDI-MS facilitates the identification of specific lipids within chloroplast membranes and other organelles. This study underscores the rapid and precise nature of ET-MALDI-MS in microalgal biomarker analysis, providing valuable insights into phytoplankton dynamics, trophic levels, and environmental processes. C. vulgaris emerges as a promising model for studying pigment composition and membrane lipid diversity, enhancing our understanding of microalgal ecosystems.

Nature provides a great source of inspiration for the development of sustainable materials with excellent properties, among which melanin with optical, electronic, and radiation protection properties are considered to be promising coloring materials. However, compared to chemical pigments, the single color, complex oxidation process, and poor solubility of natural melanin strongly limit their further applications. Here, we introduce a series of melanin-like polymeric pigments with amino acid-encoded physicochemical properties by a simple three-component reaction system. Our protocol enables artificial control of the chromophore structures through the rational design of the substrates and dopants, thereby combining the safety and functionality of biopigments with the color richness of chemical dyes. Similar to the photoprotective effect of natural melanin, the polymeric pigments showed excellent antioxidant activity in reducing free radicals and have the advantages of iridescent color, strong tinting strength, stability, and affordability. Furthermore, due to their ability to dye substrates, these biomimetic are expected to become new low-cost bioactive chromophores and find various biochemical applications such as in clothing and hair dyeing, food addition, and anticounterfeiting detection.

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

Food colorants are frequently added to processed foods since color is an important tool in the marketing of food products, influencing consumer perceptions, preferences, and purchasing behavior. While synthetic dyes currently dominate the food colorant market, consumer concern regarding their safety and sustainability is driving a demand for their replacement with naturally derived alternatives. However, natural colorants are costly compared to their synthetic counterparts as the pigment content in the native sources is usually very low and extraction can be challenging. Recent advances in the engineering of microbial metabolism have sparked interest in the development of cell factories capable of producing natural colorants from renewable resources. This review summarizes major developments within metabolic engineering for the production of nature-identical food colorants by fermentation. Additionally, it highlights common applications, formulations, and physicochemical characteristics of prevalent pigment classes. Lastly, it outlines a workflow for accelerating the optimization of cell factories for the production or derivatization of nature-identical food colorants., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Irina Borodina reports a relationship with Novo Nordisk Foundation that includes: funding grants. Irina Borodina has patent #Methods for producing betalains in yeast (WO2022253815) pending to The Technical Univeristy of Denmark. Philip Tinggaard Thomsen has patent #Methods for producing betalains in yeast (WO2022253815) pending to The Technical Univeristy of Denmark. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

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

Despite their overlooked status, weeds are increasingly recognized for their therapeutic value, aligning with historical reliance on plants for medicine and nutrition. This study investigates the medicinal potential of native weed species in Bangladesh, specifically pigments, antioxidants, and free radical scavenging abilities. Twenty different medicinal weed species were collected from the vicinity of Khulna Agricultural University and processed in the Crop Botany Department Laboratory. Pigment levels were determined using spectrophotometer analysis, and phenolics, flavonoids, and DPPH were quantified accordingly. Chlorophyll levels in leaves ranged from 216.70 ± 9.41 to 371.14 ± 28.67 µg g -1 FW, and in stems from 51.98 ± 3.21 to 315.89 ± 17.19 µg g -1 FW. Flavonoid content also varied widely, from 1,624.62 ± 102.03 to 410.00 ± 115.58 mg CE 100 g -1 FW in leaves, and from 653.08 ± 32.42 to 80.00 ± 18.86 mg CE 100 g -1 FW in stems. In case of phenolics content Euphorbia hirta L. displaying the highest total phenolic content in leaves (1,722.33 ± 417.89 mg GAE 100 g -1 FW) and Ruellia tuberosa L. in stems (977.70 ± 145.58 mg GAE 100 g -1 FW). The lowest DPPH 2.505 ± 1.028 mg mL -1 was found in Heliotropium indicum L. leaves. Hierarchical clustering links species with pigment, phenolic/flavonoid content, and antioxidant activity. PCA, involving 20 species and seven traits, explained 70.07% variability, with significant PC1 (14.82%) and PC2 (55.25%). Leaves were shown to be superior, and high-performing plants such as E. hirta and H. indicum stood out for their chemical composition and antioxidant activity. Thus, this research emphasizes the value of efficient selection while concentrating on the therapeutic potential of native weed species., Competing Interests: The authors declare that there is no conflict of interest in the article., (©2024 Sumi et al.)

The marine kingdom is an important source of a huge variety of scaffolds inspiring the design of new drugs. The complex molecules found in the oceans present a great challenge to organic and medicinal chemists. However, the wide variety of biological activities they can display is worth the effort. In this article, we present an overview of different seaweeds as potential sources of bioactive pigments with activity against neurodegenerative diseases, especially due to their neuroprotective effects. Along with a broad introduction to seaweed as a source of bioactive pigments, this review is especially focused on astaxanthin and fucoxanthin as potential neuroprotective and/or anti-neurodegenerative agents. PubMed and SciFinder were used as the main sources to search and select the most relevant scientific articles within the field.

Bacterial pigments stand out as exceptional natural bioactive compounds with versatile functionalities. The pigments represent molecules from distinct chemical categories including terpenes, terpenoids, carotenoids, pyridine, pyrrole, indole, and phenazines, which are synthesized by diverse groups of bacteria. Their spectrum of physiological activities encompasses bioactive potentials that often confer fitness advantages to facilitate the survival of bacteria amid challenging environmental conditions. A large proportion of such pigments are produced by bacterial pathogens mostly as secondary metabolites. Their multifaceted properties augment potential applications in biomedical, food, pharmaceutical, textile, paint industries, bioremediation, and in biosensor development. Apart from possessing a less detrimental impact on health with environmentally beneficial attributes, tractable and scalable production strategies render bacterial pigments a sustainable option for novel biotechnological exploration for untapped discoveries. The review offers a comprehensive account of physiological role of pigments from bacterial pathogens, production strategies, and potential applications in various biomedical and biotechnological fields. Alongside, the prospect of combining bacterial pigment research with cutting-edge approaches like nanotechnology has been discussed to highlight future endeavours., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Microalgae are a source of a wide variety of commodities, including particularly valuable pigments. The typical pigments present in microalgae are the chlorophylls, carotenoids, and phycobiliproteins. However, other types of pigments, of the family of water-soluble polyphenols, usually encountered in terrestrial plants, have been recently reported in microalgae. Among such microalgal polyphenols, many flavonoids have a yellowish hue, and are used as natural textile dyes. Besides being used as natural colorants, for example in the food or cosmetic industry, microalgal pigments also possess many bioactive properties, making them functional as nutraceutical or pharmaceutical agents. Each type of pigment, with its own chemical structure, fulfills particular biological functions. Considering both eukaryotes and prokaryotes, some species within the four most promising microalgae groups (Cyanobacteria, Rhodophyta, Chlorophyta and Heterokontophyta) are distinguished by their high contents of specific added-value pigments. To further enhance microalgae pigment contents during autotrophic cultivation, a review is made of the main related strategies adopted during the last decade, including light adjustments (quantity and quality, and the duration of the photoperiod cycle), and regard to mineral medium characteristics (salinity, nutrients concentrations, presence of inductive chemicals). In contrast to what is usually observed for growth-related pigments, accumulation of non-photosynthetic pigments (polyphenols and secondary carotenoids) requires particularly stressful conditions. Finally, pigment enrichment is also made possible with two new cutting-edge technologies, via the application of metallic nanoparticles or magnetic fields., (© 2024. The Author(s).)

Fungal azaphilones have attracted widespread attention due to their significant potential as sources of food pigments and pharmaceuticals. Genome mining and gene cluster activation represent powerful tools and strategies for discovering novel natural products and bioactive molecules. Here, a putative azaphilone biosynthetic gene cluster lut from the endophytic fungus Talaromyces sp. was identified through genome mining. By overexpressing the pathway-specific transcription factor LutB, five new sclerotiorin-type azaphilones ( 1 , 6 , 8 , and 10 - 11 ) together with seven known analogues ( 2 - 5 , 7 , 9 , 12 ) were successfully produced. Compounds 8 and 9 exhibited antibacterial activity against Bacillus subtilis with MIC values of 64 and 16 μg/mL, respectively. Compound 11 showed cytotoxic activity against HCT116 and GES-1 with IC 50 values of 10.9 and 4.9 μM, respectively, while 1 , 4 , 5 , and 7 - 10 showed no obvious cytotoxic activity. Gene inactivation experiments confirmed the role of the lut cluster in the production of compounds 1 - 12 . Subsequent feeding experiments unveiled the novel functional diversity of the dual megasynthase system. Furthermore, a LutC-LutD binary oxidoreductase system was discovered, and in combination with DFT calculations, the basic biosynthetic pathway of the sclerotiorin-type azaphilones was characterized. This study provided a good example for the discovery of new azaphilones and further uncovered the biosynthesis of these compounds.

The long-term stability of red wine color depends on the formation of polymeric pigments from anthocyanins. Although there is still a lot of uncertainty about the specific structure of this diverse group of pigments, there is consensus that they are reaction products of anthocyanins and other polyphenols. Interactions between anthocyanins and pectic polysaccharides have been suggested to stabilize anthocyanins. This study explores the impact of such interactions by adding pectin during red winemaking. The results demonstrate that these interactions induce the formation of additional polymeric pigments which enhance the pigment stability during fermentation and aging. While initial pigment formation is higher in wines with added pectin, a notable proportion of the complexes degrades in the later stages of fermentation. Presumably, tannins form insoluble complexes with pectin, reducing tannin concentration by more than 300 mg/L. Anthocyanin concentrations decrease by over 400 mg/L, and polymeric pigments double. Anthocyanins that form polymeric pigments with pectic polysaccharides expand the range of pigments in red wines with possible consequences for the sensory properties of the wine. These findings highlight the complex interactions between pectin, anthocyanins, and tannins, and their influence on pigment formation and wine composition during fermentation and aging., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Hensen, Jan-Peter reports financial support was provided by German Ministry for Economic Affairs and Energy (via AiF) and the FEI (Forschungskreis der Ernährungsindustrie e.V., Bonn). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Azaphilones represent a particular group of fascinating pigments from fungal source, with easier industrialization and lower cost than the traditional plant-derived pigments, and they also display a wide range of pharmacological activities. Herein, 28 azaphilone analogs, including 12 new ones, were obtained from the fermentation culture of a marine fungus Penicillium sclerotium UJNMF 0503. Their structures were elucidated by MS, NMR and ECD analyses, together with NMR and ECD calculations and biogenetic considerations. Among them, compounds 1 and 2 feature an unusual natural benzo[d][1,3]dioxepine ring embedded with an orthoformate unit, while 3 and 4 represent the first azaphilone examples incorporating a novel rearranged 5/6 bicyclic core and a tetrahydropyran ring on the side chain, respectively. Our bioassays revealed that half of the isolates exhibited neuroprotective potential against H 2 O 2 -induced injury on RSC96 cells, while compound 13 displayed the best rescuing capacity toward the cell viability by blocking cellular apoptosis, which was likely achieved by upregulating the PI3K/Akt signaling pathway., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jie Bao, Yan-Fen Zhao, Hua Zhang, Shan-Shan Huang, Long Wang, Chun-Ying Wang, Yu Zhang has patent #Penicillium fungus and application thereof in preparing antibacterial medicine (CN115806881) issued to Jie Bao. Lei Zhou, Wen-Min Hou, Mei-Hui Hou, Jie Bao, Peng-Wei Jing, Hao Li, Yong-Mei Wu has patent #Extraction of nitrogenophilic ketone compound and its application(CN115850231) issued to Jie Bao. Jie Bao, Yan-Fen Zhao, Kongkai Zhu, Hua Zhang, Xin-Xin Wang, Ze-Long Chen, Ruo-Ping Ma has patent #Azone compounds and their preparation methods and their application in preparation of neuroprotective drugs (CN115851454) issued to Jie Bao. Jie Bao, Yan-Fen Zhao, Hua Zhang, Xin-Xin Wang, Shan-Shan Huang, Xin-Ping Liu has patent #Azurophilic ketone compounds with effect of promoting peripheral nerve injury repair and preparation method thereof (CN115960729) issued to Jie Bao. Xin-Ping Liu, Jie Bao, Ruo-Ping Ma, Long Wang, Yan-Fen Zhao, Xin-Xin Wang, Xin-Hui Cheng, Jia-Hui Xu has patent #Preparation of benzopyran compound and its application in preparation of medicine for neurodegenerative diseases (CN116410185) issued to Jie Bao. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Naturally sourced pH-sensitive indicator films are of interest for real-time monitoring of food freshness through color changes because of their safety. Therefore, natural pigments for indicator films are required. However, pigment stability is affected by environmental factors, which can in turn affect the sensitivity and color stability of the pH-sensitive indicator film. First, natural pigments (anthocyanin, betalain, curcumin, alizarin, and shikonin) commonly used in pH-sensitive indicator films are presented. Subsequently, the mechanisms behind the change in pigment color under different pH environments and their applications in monitoring food freshness are also described. Third, influence factors, such as the sources, types, and pH sensitivity of pigments, as well as environmental parameters (light, temperature, humidity, and oxygen) of sensitivity and color stability, are analyzed. Finally, methods for improving the pH-sensitive indicator film are explored, encapsulation of natural pigments, incorporation of a hydrophobic film-forming matrix or function material, and protective layer have been shown to enhance the color stability of indicator films, the addition of copigments or mental ions, blending of different natural pigments, and the utilization of electrospinning have been proved to increase the color sensitivity of indicator films. This review could provide theoretical support for the development of naturally sourced pH-sensitive indicator films with high stability and sensitivity and facilitate the development in the field of monitoring food freshness., (© 2024 Institute of Food Technologists®.)

Flavonoids are polyphenolic plant constituents. Anthocyanins are flavonoid pigments found in higher plants that show a wide variety of colors ranging from red through purple to blue. The blue color of the flowers is mostly attributed to anthocyanins. However, only a few types of anthocyanidin, chromophore of anthocyanin, exist in nature, and the extracted pigments are unstable with the color fading away. Therefore, the wide range and stable nature of colors in flowers have remained a mystery for more than a century. The mechanism underlying anthocyanin-induced flower coloration was studied using an interdisciplinary method involving chemistry and biology. Furthermore, the chemical studies on flavonoid pigments in various edible plants, synthetic and biosynthetic studies on anthocyanins were conducted. The results of these studies have been outlined in this review., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

Ten azaphilones including one pair of new epimers and three new ones, penineulones A-E (1-5) with the same structural core of angular deflectin, were obtained from a deep-sea derived Penicillium sp. SCSIO41030 fermented on a liquid medium. Their structures including absolute configurations were elucidated using chiral-phase HPLC analysis, extensive NMR spectroscopic and HRESIMS data, ECD and NMR calculations, and by comparing NMR data with literature data. Biological assays showed that the azaphilones possessed no antitumor and anti-viral (HSV-1/2) activities at concentrations of 5.0 μM and 20 μM, respectively. In addition, azaphilones 8 and 9 showed neuroprotective effects against Aβ 25-35 -induced neurotoxicity in primary cultured cortical neurons at a concentration of 10 μM. Azaphilones 8 and 9 dramatically promoted axonal regrowth against Aβ 25-35 -induced axonal atrophy. Our study indicated that azaphilones could be promising lead compounds for neuroprotection.

Crocins are bioactive glucosylated apocarotenoids that confer a yellow pigmentation. In addition to their coloring ability, crocins offer potential health benefits because of their antioxidant and anti-inflammatory properties. These compounds are present in the flowers and fruits of a few plant species, including saffron, gardenia, Buddleja and Verbascum species. Saffron extracts have been used for the formulation of functional foods. However, there is no evidence of the use of the other plants producing crocins in the food industry. This study evaluated the effect of the addition of ground dry flowers of two Verbascum species, with antioxidant activity, as well as dry fruit powder, from a recently engineered tomato plant producing fruits that accumulate high levels of crocins, as functional ingredients during the processing of rice, wheat cous-cous and maize noodles, providing a yellow pigmentation. Correlation analyses revealed that the increased antioxidant activity in the three food matrices was due to the presence of crocins, which showed no toxicity. Furthermore, in vitro digestion showed that crocins were more bioaccessible from rice than from cous-cous or maize noodles, inferring the importance of the food matrix in bio accessibility. The obtained results showed the commercial potential of Verbascum 's flowers, as a source of crocins, natural pigments with antioxidant activities.

Maintaining wound moisture and monitoring of infection are crucial aspects of chronic wound treatment. The development of a pH-sensitive functional hydrogel dressing is an effective approach to monitor, protect, and facilitate wound healing. In this study, beet red pigment extract (BRPE) served as a native and efficient pH indicator by being grafted into silane-modified bacterial nanocellulose (BNC) to prepare a pH-sensitive wound hydrogel dressing (S-g-BNC/BRPE). FTIR confirmed the successful grafting of BRPE into the BNC matrix. The S-g-BNC/BRPE showed superior mechanical properties (0.25 MPa), swelling rate (1251 % on average), and hydrophilic properties (contact angle 21.83°). The composite exhibited a notable color change as the pH changed between 4.0 and 9.0. It appeared purple-red when the pH ranged from 4.0 to 6.0, and appeared light pink at pH 7.0 and 7.4, and appeared ginger-yellow at pH 8.0 and 9.0. Subsequently, the antioxidant activity and cytotoxicity of the composite was evaluated, its DPPH·, ABTS+, ·OH scavenging rates were 32.33 %, 19.31 %, and 30.06 %, respectively, and the cytotoxicity test clearly demonstrated the safety of the dressing. The antioxidant hydrogel dressing, fabricated with a cost-effective and easy method, not only showed excellent biocompatibility and dressing performance but could also indicated the wound state based on pH changes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

While edible algae might seem low in fat, the lipids they contain are crucial for good health and preventing chronic diseases. This study introduces a binary matrix to analyze all the polar lipids in both macroalgae (Wakame- Undaria pinnatifida , Dulse- Palmaria palmata , and Nori- Porphyra spp.) and microalgae (Spirulina- Arthrospira platensis , and Chlorella- Chlorella vulgaris ) using matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS). The key lies in a new dual matrix made by combining equimolar amounts of 1,5-diaminonaphthalene (DAN) and 9-aminoacridine (9AA). This combination solves the limitations of single matrices: 9AA is suitable for sulfur-containing lipids and acidic phospholipids, while DAN excels as an electron-transfer secondary reaction matrix for intact chlorophylls and their derivatives. By employing the equimolar binary matrix, a wider range of algal lipids, including free fatty acids, phospholipids, glycolipids, pigments, and even rare arsenosugarphospholipids were successfully detected, overcoming drawbacks related to ion suppression from readily ionizable lipids. The resulting mass spectra exhibited a good signal-to-noise ratio at a lower laser fluence and minimized background noise. This improvement stems from the binary matrix's ability to mitigate in-source decay effects, a phenomenon often encountered for certain matrices. Consequently, the data obtained are more reliable, facilitating a faster and more comprehensive exploration of algal lipidomes using high-throughput MALDI-MS/MS analysis.

Developing novel, safe, and efficient proangiogenic drugs is an important approach for the prevention and treatment of cardiovascular diseases. In this study, 4 new compounds, including 3 azaphilones ( 1 - 3 ) and 1 dihydroisocoumarin ( 4 ), as well as 13 known compounds ( 5 - 17 ), were isolated from the sea-mud-derived fungus Neopestalotiopsis sp. HN-1-6 from the Beibu Gulf of China. The structures of the new compounds were determined by NMR, MS, ECD, and NMR calculations. Compounds 3 , 5 , and 7 exhibited noteworthy proangiogenic activities in a zebrafish model at a concentration of 40 μM, without displaying cytotoxicity toward five human cell lines. In addition, some compounds demonstrated antibacterial effects against Staphylococcus aureus , Escherichia coli , and Candida albicans , with MIC values ranging from 64 μg/mL to 256 μg/mL.

Lanmaoa asiatica G. Wu & Zhu L. Yang and L. macrocarpa N. K. Zeng, H. Chai & S. Jiang are two important gourmet bolete in China, and locally named "Jian Shou Qing" meaning their fruiting bodies turn blue after bruising. The genus represents a distinct lineage in Boletaceae. The pigment(s) associated with the discoloration in Lanmaoa has not been identified. The aim of this study was to determine the pigment(s) underpinning the bluing reaction of L. asiatica and L. macrocarpa when bruised. Potential compounds were isolated by HPLC and identified by LC-HRMS and NMR. In total five to six pigments of hydroxylated pulvinic acid derivatives were detected with similar distribution patterns in both L. asiatica and L. macrocarpa, which by abundance were variegatic acid, variegatorubin, xerocomic acid (and/or isoxerocomic acid), xerocomorubin, and atromentic acid. Variegatic acid, the most abundant pigment, was isolated by HPLC, and the structure was further characterized by NMR. The amount of variegatic acid increased after regular cooking, which may suggest its enhanced health benefit as human diet. The types of pigments that cause bluing reactions often differ among families of Boletales. Our results showed that the pigments in Lanmaoa belong to the category of hydroxylated pulvinic acid derivatives, the major bluing compounds in Boletaceae., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

The identification of more efficient, clean, secure, and competitive energy supply is necessary to align with the needs of sustainable devices. For this reason, a study for developing innovative dye-sensitized solar cells (DSSCs) based on microbial pigments is reported starting from Talaromyces atroroseus GH2. The fungus was cultivated by fermentation and the extracellular pigment extract was characterized by HPLC-DAD-ESI-MS analyses. The most abundant compound among the 22 azaphilone-type pigments identified was represented by PP-O. The device's behavior was investigated in relation to electrolyte and pH for verifying the stability on time and the photovoltaic performance. Devices obtained were characterized by UV-vis measurements to verify the absorbance intensity and transmittance percentage. Moreover, photovoltaic parameters through photo-electrochemical measurements (I-V curves) and impedance characteristics by Electrochemical Impedance Spectroscopy (EIS) were determined. The best microbial device showed a short-circuit current density (Jsc) of 0.69 mA/cm 2 , an open-circuit photo-voltage (Voc) of 0.27 V and a Fill Factor (FF) of 0.60. Furthermore, the power conversion efficiency (PCE) of the device was 0.11%. Thus, the present study demonstrated the potential of microbial origin pigments for developing DSSCs., (© 2024. The Author(s).)

Red phycoerythrin (R-PE) is a highly valuable protein found in an edible seaweed, Pyropia yezoensis . It is used extensively in biotechnological applications due to its strong fluorescence and stability in diverse environments. However, the current methods for extracting and purifying R-PE are costly and unsustainable. The aim of the present study was to enhance the financial viability of the process by improving the extraction and purification of R-PE from dried P. yezoensis and to further enhance R-PE value by incorporating it into a tandem dye for molecular biology applications. A combination of ultrafiltration, ion exchange chromatography, and gel filtration yielded concentrated (1 mg·mL -1 ) R-PE at 99% purity. Using purified PE and Cyanine5 (Cy5), an organic tandem dye, phycoerythrin-Cy5 (PE-Cy5), was subsequently established. In comparison to a commercially available tandem dye, PE-Cy5 exhibited 202.3% stronger fluorescence, rendering it suitable for imaging and analyzes that require high sensitivity, enhanced signal-to-noise ratio, broad dynamic range, or shorter exposure times to minimize potential damage to samples. The techno-economic analysis confirmed the financial feasibility of the innovative technique for the extraction and purification of R-PE and PE-Cy5 production.

Carotenoids are yellow, orange, and red pigments commonly found in plants. In leaves, these molecules are essential for photosynthesis, but they also play a major role in plant growth and development. Efficiently monitoring concentrations of specific carotenoids in plant tissues could help to explain plant responses to environmental stressors, infection and disease, fertilization, and other conditions. Previously, Raman methods have been used to demonstrate a correlation between plant fitness and the carotenoid content of leaves. Due to solvatochromatic effects and structural similarities within the carotenoid family, current Raman spectroscopy techniques struggle to assign signals to specific carotenoids with certainty, complicating the determination of amounts of individual carotenoids present in a sample. In this work, we use thin layer chromatography-Raman spectroscopy, or TLC-Raman, to identify and quantify carotenoids extracted from tomato leaves. These quick and accurate methods could be applied to study the relationship between pigment content and a number of factors affecting plant health.

Carthami Flos(flowers of Carthamus tinctorius) with the effects of activating blood, dredging meridians, dissipating stasis, and relieving pain is one of the commonly used traditional Chinese medicines for promoting blood circulation and resolving stasis in clinical practice. So far, more than 210 compounds in Carthami Flos have been isolated and reported, including quinochalcones(safflower yellow pigments and red pigments), flavonoids, spermidines, alkaloids, polyacetylenes, and organic acids. Safflower yellow pigments, as the main water-soluble active components of Carthami Flos, is commonly obtained by the water extraction method, while red pigments are commonly obtained by the alkali extraction and acid precipitation method. In recent years, natural deep eutectic solvents as green solvents have demonstrated promising application prospects in the extraction and separation of pigments from Carthami Flos. This review systematically summarizes the chemical constituents of Carthami Flos and analyzes the extraction process of pigment components from Carthami Flos, aiming to provide a reference for further utilization of Carthami Flos resources.

The aim of this study was to investigate the production, stability and applicability of colorants produced by filamentous fungi isolated from soil samples from the Amazon. Initially, the isolates were evaluated in a screening for the production of colorants. The influences of cultivation and nutritional conditions on the production of colorants by fungal isolates were investigated. The colorants produced by selected fungal isolates were chemically characterized using the Liquid Chromatography-Mass Spectrometry technique. The antimicrobial and cytotoxic activities, stability evaluation and applicability of the colorants were investigated. As results, we observed that the isolates Penicillium sclerotiorum P3SO224, Clonostachys rosea P2SO329 and Penicillium gravinicasei P3SO332 stood out since they produced the most intense colorants. Compounds produced by Penicillium sclerotiorum P3SO224 and Clonostachys rosea P2SO329 were identified as sclerotiorin and penicillic acid. The colorant fraction (EtOAc) produced by these species has antimicrobial activity, stability at temperature and at different pHs, stability when exposure to light and UV, and when exposed to different concentrations of salts, as well as being nontoxic and having the ability to dye fabrics and be used as a pigment in creams and soap. Considering the results found in this study, it was concluded that fungi from the soil in the Amazon have the potential to produce colorants with applications in the textile and pharmaceutical industries., (© 2023 Wiley-VCH GmbH.)

Colored oyster mushrooms species of genus Pleurotus are a variety of edible mushrooms that attract a lot of interest among the consumers and scientists due to its scientific evidence that they have promising health benefits. However, information on their characteristics and properties is still scarce. Consequently, it is important to determine the potential health benefits of the mushrooms. This review paper presents an overview of functional properties and nutritional values of colored oyster mushrooms (Pleurotus spp.). It particularly discusses the types of pigments present in Pleurotus spp., their characteristics, and potential nutritional values. Pigments such as melanin, carotenoids, and flavonoids are reported to be present in colored oyster mushrooms. Moreover, the antioxidant compounds of these mushrooms have been unveiled, demonstrating their potential to counteract oxidative stress and improve general health. In addition, the investigation into the nutritional characteristics of the mushrooms reveals encouraging aspects for their incorporation into dietary considerations. Thus, it can be concluded that colored Pleurotus species have an immense amount of potential for use as natural colorants, as well as nutritious and antioxidant-rich compounds. These mushrooms represent an important advancement in the search for functional foods due to their significant nutrients such as proteins, amino acids, carbohydrates, and fibers.

Algae are exclusively aquatic photosynthetic organisms that are microscopic or macroscopic, unicellular or multicellular and distributed across the globe. They are a potential source of food, feed, medicine and natural pigments. A variety of natural pigments are available from algae including chlorophyll a, b, c d, phycobiliproteins, carotenes and xanthophylls. The xanthophylls include acyloxyfucoxanthin, alloxanthin, astaxanthin, crocoxanthin, diadinoxanthin, diatoxanthin, fucoxanthin, loroxanthin, monadoxanthin, neoxanthin, nostoxanthin, perdinin, Prasinoxanthin, siphonaxanthin, vaucheriaxanthin, violaxanthin, lutein, zeaxanthin, β-cryptoxanthin, while carotenes include echinenone, α-carotene, β-carotene, γ-carotene, lycopene, phytoene, phytofluene. These pigments have applications as pharmaceuticals and nutraceuticals and in the food industry for beverages and animal feed production. The conventional methods for the extraction of pigments are solid-liquid extraction, liquid-liquid extraction and soxhlet extraction. All these methods are less efficient, time-consuming and have higher solvent consumption. For a standardized extraction of natural pigments from algal biomass advanced procedures are in practice which includes Supercritical fluid extraction, Pressurized liquid extraction, Microwave-assisted extraction, Pulsed electric field, Moderate electric field, Ultrahigh pressure extraction, Ultrasound-assisted extraction, Subcritical dimethyl ether extraction, Enzyme assisted extraction and Natural deep eutectic solvents. In the present review, these methods for pigment extraction from algae are discussed in detail.

In Chile, as in the rest of the world, only a small fraction of the fungal diversity inhabiting the wide variety of its ecosystems is known. This diversity must hide an inestimable richness of species with interesting biotechnological potential, including fungal pigment producers. Recently, interest in filamentous fungi has increased significantly due to their importance as alternative sources of pigments and colorants that are environmentally and human health friendly. As a result, fungal pigments are gaining importance in various industrial applications, such as food, textiles, pharmaceuticals, cosmetics, etc. The increasing consumer demand for "green label" natural colorants requires the exploration of different ecosystems in search of new fungal species that are efficient producers of different pigment with a wide range of colors and ideally without the co-production of mycotoxins. However, advances are also needed in pigment production processes through fermentation, scale-up from laboratory to industrial scale, and final product formulation and marketing. In this respect, the journey is still full of challenges for scientists and entrepreneurs. This chapter describes studies on pigment-producing fungi collected in the forests of central-southern Chile. Aspects such as the exploration of potential candidates as sources of extracellular pigments, the optimization of pigment production by submerged fermentation, methods of pigment extraction and purification for subsequent chemical characterization, and formulation (by microencapsulation) for potential cosmetic applications are highlighted. This potential use is due to the outstanding bioactivity of most fungal pigments, making them interesting functional ingredients for many applications. Finally, the use of fungal pigments for textile and spalting applications is discussed., (Copyright © 2024. Published by Elsevier Inc.)

From the dried leaves of Lithocarpus polystachyus, yellow pigments, lithocarputins B (11) and C (12), were isolated with a colorless dihydrochalcone dimer, lithocarputin A (10). The pigments 11 and 12 are dimeric dihydrochalcone glycosides with bicyclo[3.2.1]octane structures. Each pigment is a diastereomeric mixture with enantiomeric aglycones that could not be separated. The production mechanisms of the pigments were proposed based on the in vitro enzymatic preparation from trilobatin (1), the major dihydrochalcone glucoside of L. polystachyus. The majority of the pigments in the dried leaves were the oligomers of the dihydrochalcone glycosides generated by a mechanism similar to dimerization. The pigments are probably artifacts produced in the drying process. This is the first report disclosing a detailed chemical mechanism for pigment formation from dihydrochalcone., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Aims: Extreme environment of microbial fermentation is the focus of research, which provides new thinking for the production and application of Monascus pigments (MPs). In this work, the high-sugar synergistic high-salt stress fermentation (HSSF) of MPs was investigated., Methods and Results: The Monascus fungus grew well under HSSF conditions with 35 g L-1 NaCl and 150 g L-1 glucose, and the extracellular yellow pigment and intracellular orange pigment yield in HSSF was 98% and 43% higher than that in conventional fermentation, respectively. Moreover, the mycelial morphology was maintained in a better status with more branches and complete surface structure, indicating good biocatalytic activity for pigment synthesis. Four extracellular yellow pigments (Y1, Y2, Y3, and Y4) were transformed into each other, and ratio of the relative content of intracellular orange pigments to yellow pigments (O/Y) significantly (P < 0.05) changed. Moreover, the ratio of unsaturated fatty acids to saturated fatty acids (unsaturated/saturated) was significantly (P < 0.05) increased, indicating that the metabolism and secretion of intracellular and extracellular pigment might be regulated in HSSF. The pigment biosynthesis genes mppB, mppC, mppD, MpPKS5, and MpFasB2 were up-regulated, whereas the genes mppR1, mppR2, and mppE were down-regulated, suggesting that the gene expression to regulate pigment biosynthesis might be a dynamic change process in HSSF., Conclusions: The HSSF system of MPs is successfully performed to improve the pigment yields. Mycelial morphology is varied to enhanced pigment secretion, and gene expression is dynamically regulated to promote pigment accumulation in HSSF., (© The Author(s) 2023. Published by Oxford University Press on behalf of Applied Microbiology International.)

Natural pigments are important sources for the screening of bioactive lead compounds. This article reviewed the chemistry and therapeutic potentials of over 570 colored molecules from plants, fungi, bacteria, insects, algae, and marine sources. Moreover, related biological activities, advanced extraction, and identification approaches were reviewed. A variety of biological activities, including cytotoxicity against cancer cells, antioxidant, anti-inflammatory, wound healing, anti-microbial, antiviral, and anti-protozoal activities, have been reported for different pigments. Considering their structural backbone, they were classified as naphthoquinones, carotenoids, flavonoids, xanthones, anthocyanins, benzotropolones, alkaloids, terpenoids, isoprenoids, and non-isoprenoids. Alkaloid pigments were mostly isolated from bacteria and marine sources, while flavonoids were mostly found in plants and mushrooms. Colored quinones and xanthones were mostly extracted from plants and fungi, while colored polyketides and terpenoids are often found in marine sources and fungi. Carotenoids are mostly distributed among bacteria, followed by fungi and plants. The pigments isolated from insects have different structures, but among them, carotenoids and quinone/xanthone are the most important. Considering good manufacturing practices, the current permitted natural colorants are: Carotenoids (canthaxanthin, β-carotene, β-apo-8'-carotenal, annatto, astaxanthin) and their sources, lycopene, anthocyanins, betanin, chlorophyllins, spirulina extract, carmine and cochineal extract, henna, riboflavin, pyrogallol, logwood extract, guaiazulene, turmeric, and soy leghemoglobin., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

The present study explores natural pigments as sustainable alternatives to synthetic textile dyes. Due to their therapeutic applications and easy production, fungal pigments have gained attention. However, data on pigment production using solid-state fermentation and optimization is limited. Milk whey was used to grow Talaromyces sp., followed by an evaluation of pigment production in solid and liquid media. Pineapple peels were used as a cost-effective substrate for pigment production, and a one-factor-at-a-time approach was used to enhance pigment production. Pineapple peel-based media produced 0.523 ± 0.231 mg/g of pigment after eight days of incubation. The crude pigment had promising antibacterial and significant antioxidant properties. The extraction fungal pigment's possible use as an eco-friendly textile dye was assessed through fabric dyeing experiments with different mordants. This work contributes to the valorization of agricultural waste and provides insight into using fungal pigments as sustainable alternatives to synthetic textile dyes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Natural plant pigments are safe and have low toxicity, with various nutrients and biological activities. However, the extraction, preservation, and application of pigments are limited due to the instability of natural pigments. Therefore, it is necessary to examine the extraction and application processes of natural plant pigments in detail. This review discusses the classification, extraction methods, biological activities, and modification methods that could improve the stability of various pigments from plants, providing a reference for applying natural plant pigments in the industry and the cosmetics, food, and pharmaceutical industries.