Pigment Yield Research Articles

Fusarium verticillioides pigment: production, response surface optimization, gamma irradiation and encapsulation studies

BackgroundNatural 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.ResultsA 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.ConclusionThis 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.

Green and sustainable recovery of polyphenols, flavonoids, alkaloids, and pigments from green tea leaves: Comparative analysis of Soxhlet, accelerated solvent, and supercritical fluid extraction techniques

The growing interest in green tea extracts for their applications in pharmaceutical, food, and cosmetic industries underscores the need for environmentally sustainable extraction methods. This study presents optimized strategies for the green recovery of bioactive compounds from Gun powder green tea leaves using Soxhlet extraction, accelerated solvent extraction, and supercritical fluid extraction techniques. By varying extraction solvents (supercritical CO2, ethanol, water, and their combinations) and temperatures (from 35 to 140 °C), high yields of polyphenols, flavonoids, alkaloids, and pigments were achieved. Key bioactive compounds extracted in significant quantities included caffeine (23.8 mass%), chlorophyll A (8.1 mg/g), chlorophyll B (0.7 mg/g), carotenoids (0.4 mg/g), epicatechin (7.7 mass%), catechin gallate (4.6 mass%), and epigallocatechin-3-gallate (30.2 mass%). The extract obtained in optimized processes demonstrated potent antioxidant activity (IC50 up to 88 μg/mL), strong antimicrobial activity (including methicillin-resistant Staphylococcus aureus- MRSA) with MIC up to 0.06 mg/mL, and selective anticancer activity against colon cancer cells. The presented findings provide a theoretical basis and technical guidance for enhancing the sustainable concentration of natural bioactive compounds, promoting their use in various industrial applications.

Prodigiosin, a promising biocontrol agent against Thaumetopoea wilkinsoni (Tams, 1926) (Lepidoptera: Notodontidae)

Serratia marcescens Bizio (Enterobacteriaceae: Serratia) is an entomopathogenic bacterium that produces hydrolytic enzymes and toxins. It also produces a pigment with various biological properties called prodigiosin. The study was conducted at Bilecik Seyh Edebali University in 2023. In this study, the effects of medium, incubation temperature and time on the process of prodigiosin production by S. marcescens strain Se9 and the extraction efficiency of different solvents were optimized for the first time using the orthogonal Taguchi array design. The optimal yield of pigment was achieved by methanol extraction from bacteria grown in tyriptic soy broth medium at 30ºC for 96 hours. The yield of prodigiosin pigment was 83.4±1.7 mg/L in the validation experiment conducted under the optimum conditions determined. The insecticidal potential of pigment against the larvae of Thaumetopoea wilkinsoni (Tams, 1926) (Lepidoptera, Notodontidae) was demonstrated for the first time. While the mortality rate in larvae exposed to 1000 ppm of the pigment was only 40%, it was observed that doubling the applied concentration led to a significant increase in larval mortality, reaching 91%. The LC50 value of the pigment for the fourth larval stage of T. wilkinsoni was determined to be 1192 ppm. The study showed that the pigment prodigiosin may be a promising biocontrol agent for the control of T. wilkinsoni.

Improved yield of UV and heat-stable Monascus yellow pigment by statistical optimization of solid-state fermentation conditions and extraction process

Monascus species are well-known for their ability to produce biocolorants. A high-performing strain, M. purpureus F2–19, was recently developed by genome shuffling. Here, the entire bioprocess, starting from solid-state fermentation conditions to the extraction method, was statistically optimized to improve yellow pigment yield by the strain. Among culture conditions, monosodium glutamate concentration (used as nitrogen source), moisture content, and incubation period significantly influenced pigment production using less expensive broken rice as a substrate. Post-optimization, a yield of 1548.4 ± 14.6 AU/g was achieved, representing a 9.7-fold increase over the primary condition. The statistical model developed using central composite design of response surface methodology (CCD-RSM) is highly significant, with a P value of <0.0001. Similarly, a significant model (P < 0.0001) for extraction improved pigment yield further by 1.16-fold (actual output: 1796.4 ± 13.4 AU/g). The pigment remained highly stable with a preservation rate of ~90 % after 2.5 h exposure to a high temperature of 100 °C or UV light (254 nm). Even autoclaving at 121 °C for 15 min preserved 96.9 % of the pigment. These values are higher than reported for other commercial microbial yellow pigments, riboflavin, β-carotene, or lutein, thus highlighting its potential as a natural food colorant. Liquid chromatography-mass spectrometry (LC-MS) of the pigment identified nine distinct yellow compounds, with monascin being the most abundant. Thus, the optimized bioprocess would facilitate economical large-scale production of the yellow pigment; but its implementation still requires efficient selection of bioreactors and optimizations of scaling-up, especially the heat and mass transfer parameters.

Electric fields to support microalgae growth with a differentiated biochemical composition

Microalgae are a group of microorganisms well-known for their high metabolic plasticity and biomass with commercial interest for several industries. In the present work, the influence of in-situ electric field application (INEF) on the growth and biochemical composition of Pavlova gyrans was, for the first time, assessed. Electrical protocols were tested, namely by applying INEF in different growth stages, in varying treatment times and even by combining it with dark phase of cells' photoperiod. INEF did not promote a stimulatory effect on growth but influenced the biochemical composition of P. gyrans – maximum increases of 74.9 and 66.2 % in the chlorophyll a and carotenoid content and of 4.72, 18.7 and 5.41 % in the lipid, carbohydrate and protein content were observed in independent experiments. Hence, with this study, the potential of INEF application as a strategy to modulate growth and to promote biochemical composition alterations was proven. Industrial relevanceMicroalgae, with their unique ability to efficiently convert sunlight and carbon dioxide into biomass, offer a sustainable platform for the synthesis of diverse bioactive compounds. By subjecting microalgae to controlled electric stress conditions, their metabolic pathways can be redirected towards the production of specific target compounds. This strategy has the potential to enhance the yield of high-value molecules, including biofuels, pharmaceuticals, nutraceuticals, and pigments, whilst minimizing resource inputs. Additionally, metabolic stress responses in microalgae often trigger the accumulation of secondary metabolites with bioactive properties. Harnessing the metabolic plasticity of microalgae through controlled stress manipulation represents a cutting-edge strategy for sustainable and economically viable bioproduction systems that align with the goals of green chemistry and circular economy principles.

Biosynthesis and Extraction of Chlorophyll, Carotenoids, Anthocyanins, and Betalaine In Vivo and In Vitro.

As natural bioactive compounds, plant pigments play crucial roles not only in plant phenotype, growth, development, and adaptation to stress but also hold unique value in biotechnology, healthcare, and industrial applications. There is growing interest in the biosynthesis and acquisition of plant pigments. Thus, this paper explores emerging extraction methods of natural pigments and elucidates the biosynthesis pathways of four key plant pigments, chlorophylls, carotenoids, anthocyanins, and betalaine in vivo and in vitro. We comprehensively discuss the application of solvent, supercritical fluid [extraction], ultrasonic, and microwave-assisted extraction techniques, as well as introducing key enzymes, precursors, and synthetic pathways involved in pigment synthesis. δ-Aminolevulinic acid represents a pivotal initiating enzyme for chlorophyll synthesis, whereas isopentenylpyrophosphate, (IPP) and dimethylallyl pyrophosphate, (DMAPP) are closely associated with carotenoid biosynthesis. Phenylalanine and tyrosine are critical substances for anthocyanin and betalaine synthesis, respectively. Hence, crucial genes such as chlI, crtB, PGT8, CYP76AD1, and BvDODA can be employed for heterologous biosynthesis in vitro to meet the demand for increased plant pigment amount. As a pivotal determinant of plant coloration, an in-depth exploration into the high-quality acquisition of plant pigments can provide a basis for developing superior pigments and offer new insights into increasing pigment yield.

Photoperiod and temperature interactions drive the latitudinal distribution of Laminaria hyperborea (Laminariales, Phaeophyceae) under climate change.

Due to global rises in temperature, recent studies predict marine species shifting toward higher latitudes. We investigated the impact of interacting abiotic drivers on the distribution potential of the temperate kelp Laminaria hyperborea. The ecosystem engineering species is widespread along European coasts but has not yet been observed in the High Arctic, although it can survive several months of low temperatures and darkness. To investigate its ability to extend northward in future, we conducted a long-term multifactorial experiment with sporophytes from Porsangerfjorden, Norway-close to the species' documented northernmost distribution margin. The samples were exposed to three different photoperiods (PolarDay, LongDay, and PolarNight) at 0°C, 5°C, and 10°C for 3 months. Optimum quantum yield of photosynthesis (Fv/Fm), dry weight, pigments, phlorotannins, and storage carbohydrates were monitored. Both physiological and biochemical parameters revealed that L. hyperborea was strongly influenced by the different photoperiods and their interaction with temperature, while temperature alone exerted only minor effects. The Fv/Fm data were integrated into a species distribution model to project a possible northward expansion of L. hyperborea. The combination of extended day lengths and low temperatures appeared to be the limiting reason for northward spread of L. hyperborea until recently. However, with water temperatures reaching 10°C in summer, this kelp will be able to thrive also in the High Arctic. Moreover, no evidence of stress to Arctic winter warming was observed. Consequently, L. hyperborea has a high potential for spreading northward with further warming which may significantly affect the structure and function of Arctic ecosystems.

Optimization and extraction of annatto pigments obtained from Bixa orellana L. using supercritical fluid extraction

Traditionally, various techniques like water, vegetable oil, and solvent extraction are used to extract annatto pigments, a natural coloring agent derived from the Bixa orellana L. shrub. These traditional extraction methods can be time consuming and yield minimal pigment concentrations. This study explores an innovative approach to extract the maximum pigments from the annatto seed using supercritical fluid extraction (SFE). Fresh, extracted aqueous, and peeled samples of annatto powder were used at different temperatures (40, 45, and 50 °C) using different solvents of ethanol, methanol, and ethyl acetate with 99 % purity. The optimal extraction condition in supercritical fluid extraction is obtained with an aqueous sample treated with methanol solvent at 45 °C that yields 4.62 % norbixin, 2.49 % bixin, and a hue angle of 24.85⁰, achieving a high desirability value (0.949). Response surface method (RSM) was used to optimize the extraction procedure to obtain a higher yield of annatto pigments. In addition, for optimized conditions, the total phenols and antioxidants assay yielded 3.8 mg GAE/g and 51 % inhibition. HPLC analysis confirmed norbixin in the extracts obtained with a retention time of 38.40 min. This method offers a significant boost in pigment extraction efficiency, but also minimizes processing time. These combined advantages position it as a potentially superior approach for producing annatto pigments with enhanced concentration and purity.

Function Analysis of a Maize Endo-1,4-β-xylanase Gene ZmHSL in Response to High-Temperature Stress.

Rising temperature is a major threat to the normal growth and development of maize, resulting in low yield production and quality. The mechanism of maize in response to heat stress remains uncertain. In this study, a maize mutant Zmhsl-1 (heat sensitive leaves) with wilting and curling leaves under high temperatures was identified from maize Zheng 58 (Z58) mutant lines generated by ethyl methanesulfonate (EMS) mutagenesis. The Zmhsl-1 plants were more sensitive to increased temperature than Z58 in the field during growth season. The Zmhsl-1 plants had lower plant height, lower yield, and lower content of photosynthetic pigments. A bulked segregant analysis coupled with whole-genome sequencing (BSA-seq) enabled the identification of the corresponding gene, named ZmHSL, which encodes an endo-β-1,4-xylanase from the GH10 family. The loss-of-function of ZmHSL resulted in reduced lignin content in Zmhsl-1 plants, leading to defects in water transport and more severe leaf wilting with the increase in temperature. RNA-seq analysis revealed that the differentially expressed genes identified between Z58 and Zmhsl-1 plants are mainly related to heat stress-responsive genes and unfolded protein response genes. All these data indicated that ZmHSL plays a key role in lignin synthesis, and its defective mutation causes changes in the cell wall structure and gene expression patterns, which impedes water transport and confers higher sensitivity to high-temperature stress.

Carotenoid content in Ulva lactuca cultivated under aquaculture conditions and collected from intertidal beds in southeastern Brazil: biotechnological implications for biomass use and storage

Ulva lactuca is an edible green macroalga (Chlorophyta) that can be produced in cultivation systems; it is a natural source of high-value molecules. Ulva lactuca produces metabolites including carotenoids, which are pigments with antioxidant properties that are in high demand in the health and nutraceutical industries and improve the nutritional quality of U. lactuca biomass. We studied the carotenoid and chlorophyll content in U. lactuca thalli collected in 3 different environments in the state of Rio de Janeiro, Brazil: the intertidal beds of the urban beaches of Arpoador and Boa Viagem and a continental integrated multi-trophic aquaculture (IMTA) facility. Carotenoid conservation was evaluated during 1 week, 2 weeks, and 4 weeks of storage. We compared the molecules in fresh U. lactuca collected during the dry season (July 2018) and rainy season (February 2019). The content of carotenoids, such as β-carotene + zeaxanthin, lutein + antheraxanthin, violaxanthin, neoxanthin, and their derivatives (aurochrome and auroxanthin), were analyzed in 100% acetone extracts by ultraviolet visible (UV/vis) spectrophotometry and monitored by thin layer chromatography (TLC) and proton nuclear magnetic resonance (1H-NMR). The extracts of dried U. lactuca produced in the IMTA facility presented higher pigment yields than the dried biomass collected from intertidal beds. Over 4 weeks of storage, carotenoids were well conserved in U. lactuca produced in the IMTA facility, in contrast to what was observed in U. lactuca collected from the intertidal beds, which showed carotenoid losses. In addition, we observed differences in carotenoid content between the dry and rainy seasons in U. lactuca collected from Boa Viagem Beach. However, the U. lactuca collected from Arpoador Beach or produced by the IMTA facility only exhibited significant differences in chlorophyll content. We conclude that U. lactuca produced by the IMTA facility constitutes a potential source of pigments such as β-carotene, lutein, and violaxanthin.

Ionic liquid and ultrasound as a fast and innovative combination for improved extraction of Chlorella sorokiniana-derived carotenoids

Chlorella sorokiniana is a microalgae with high amounts of carotenoids, but the extraction methods need to be improved. This work hypothesized that the combination of ionic liquids (ILs) and ultrasound would provide a fast and efficient process for carotenoid extraction, allowing for the reuse of ILs in several extractive cycles. This study aimed to develop an improved ILs/ultrasound-based method for extracting carotenoids from C. sorokiniana. The potential reuse of ILs in five consecutive extraction cycles and the recovery of carotenoids was also examined. Moreover, the antioxidant activity of the carotenoid extracts and their effects on metabolic cell viability and cell death were investigated using HT22 neuronal cells. Initial tests with four ILs and acetone as a control were carried out in an ultrasonic probe. The ILs (1-butyl-3-methylimidazolium chloride [BMIM][Cl]; 1-hexyl-3-methylimidazolium chloride [HMIM][Cl]) were selected for the 25−1 fractional experimental design. The maximized parameters obtained in the experimental design were the following: IL ([HMIM][Cl]), a 1:10 solid-liquid ratio, a 1:4 IL-cosolvent ratio, and two repetitions of extraction with 7.5 min (with an extraction yield of 1.29 mg·g‐1 of dry matter). A total of 11 carotenoids were separated, and nine were identified, the major ones being lutein and β-carotene. [HMIM][Cl] recyclability using resin Amberlite XAD-7HP was efficient for at least five cycles. On average, 91 % of the IL was recovered, and the pigment yield increased by 40 %. The antioxidant activities of the extracts obtained using [HMIM][Cl] and acetone were 1.65 μmol and 2.32 μmol of α-tocopherol, respectively. Both extracts (≤ 4.0 μg·mL‐1) exhibited no significant toxicity to HT22 cells. The proposed method is an innovative and improved approach for carotenoid extraction from C. sorokiniana due to its short extraction times and high process yield. [HMIM][Cl] demonstrated stability in reuse cycles and proved to have the potential for obtaining carotenoids from C. sorokiniana.

Research on pear residue dietary fiber and Monascus pigments extracted through liquid fermentation.

Pear residue, a byproduct of pear juice extraction, is rich in soluble sugar, vitamins, minerals, and cellulose. This study utilized Monascus anka in liquid fermentation to extract dietary fiber (DF) from pear residue, and the structural and functional characteristics of the DF were analyzed. Soluble DF (SDF) content was increased from 7.9/100g to 12.6g/100g, with a reduction of average particle size from 532.4 to 383.0nm by fermenting with M. anka. Scanning electron microscopy and infrared spectroscopic analysis revealed more porous and looser structures in Monascus pear residue DF (MPDF). Water-, oil-holding, and swelling capacities of MPDF were also enhanced. UV-visible spectral analysis showed that the yield of yellow pigment in Monascus pear residue fermentation broth (MPFB) was slightly higher than that in the Monascus blank control fermentation broth. The citrinin content in MPFB and M. anka seed broth was 0.90 and 0.98ug/mL, respectively. Therefore, liquid fermentation with M. anka improved the structural and functional properties of MPDF, suggesting its potential as a functional ingredient in food.

Insight into selenium biofortification and the selenite metabolic mechanism of Monascus ruber M7

Monascus species are functional fermentation fungi with great potential for selenium (Se) supplementation. This study investigated the effects of Se bio-fortification on the growth, morphology, and biosynthesis of Monascus ruber M7. The results demonstrated a significant increase in the yield of orange and red Monascus pigments (MPs) in red yeast rice (RYR) by 38.52% and 36.57%, respectively, under 20 μg/mL of selenite pressure. Meanwhile, the production of citrinin (CIT), a mycotoxin, decreased from 244.47 μg/g to 175.01 μg/g. Transcriptome analysis revealed significant upregulation of twelve genes involved in MPs biosynthesis, specifically MpigE, MpigF, and MpigN, and downregulation of four genes (mrr3, mrr4, mrr7, and mrr8) associated with CIT biosynthesis. Additionally, three genes encoding cysteine synthase cysK (Log2FC = 1.6), methionine synthase metH (Log2FC = 2.2), and methionyl-tRNA synthetase metG (Log2FC = 1.8) in selenocompound metabolism showed significantly upregulated. These findings provide insights into Se biotransformation and metabolism in filamentous fungi.

OPTIMIZING PIGMENT PRODUCTION FROM PENICILLIUM SP. FOR SUSTAINABLE SILK DYEING

This study explores the use of microbial pigments from Penicillium sp. as a sustainable alternative to synthetic dyes in textile dyeing, focusing on optimizing pigment production and assessing color fastness on silk. Static Potato Dextrose Broth (PDB) at 28°C produced the highest concentration of red pigment after 27 days of incubation, with an optical density (O.D) of 1.010 at λmax = 530 nm. In contrast, 15°C resulted in slower pigment production (O.D = 0.860), and 37°C showed negligible growth. Adjusting the PDB pH to 5 increased pigment yield, aligning with previous studies showing Penicillium sp. thrive in acidic conditions. The final broth pH decreased to 4.0 due to organic acid production by the fungus.Silk samples dyed with these pigments were evaluated for color strength and fastness. The colorimetric values indicated moderate color intensity (K/S = 4.25) with a bright, pastel-like appearance (L* = 81.23), and a warm reddish-yellow hue (a* = 9.23, b* = 6.48). Fastness tests showed excellent performance for dry rub (rating 5), good results for wet rub (rating 4), and favorable wash fastness (rating 4 for staining and color change). However, light fastness was lower, suggesting potential fading under prolonged exposure.Overall, the study identifies Penicillium sp. as a promising source of natural dyes for silk, with optimized fermentation conditions (PDB, 28°C, pH 5, 27 days) leading to high pigment yield and strong fastness performance, offering a sustainable alternative to synthetic dyes in textiles.

Different wavelengths of LED irradiation promote secondary metabolite production in Pycnoporus sanguineus for antioxidant and immunomodulatory applications.

Pycnoporus sanguineus is a fungus of the phylum Basidiomycota that has many applications in traditional medicine, modern pharmaceuticals, and agricultural industries. Light plays an essential role in the metabolism, growth, and development of fungi. This study evaluated the mycelial growth and antioxidant and anti-inflammatory activities in P. sanguineus fermentation broth (PFB) cultured under different wavelengths of LED irradiation or in the dark. Compared to the dark cultures, the dry weight of mycelia in red- and yellow-light cultures decreased by 37 and 35% and the yields of pigments increased by 30.92 ± 2.18mg and 31.75 ± 3.06mg, respectively. Compared with the dark culture, the DPPH free radical scavenging ability, ABTS+ free radical scavenging capacity, and reducing power of yellow-light cultures increased significantly, and their total phenolic content peaked at 180.0 ± 8.34μg/mL. However, the reducing power in blue-light cultures was significantly reduced, though the total phenol content did not vary with that of dark cultures. In LPS- and IFN-γ-stimulated RAW 264.7 cells, nitrite release was significantly reduced in the red and yellow light-irradiated PFB compared with the dark culture. In the dark, yellow-, and green-light cultures, TNF-α production in the inflamed RAW 264.7 cells was inhibited by 62, 46, and 14%, respectively. With red-, blue-, and white-light irradiation, TNF-α production was significantly enhanced. Based on these results, we propose that by adjusting the wavelength of the light source during culture, one can effectively modulate the growth, development, and metabolism of P. sanguineus.

Carotenoids: Overview of the main methods and conditions of their preparation

Carotenoids represent a group of isoprenoid pigments whose high biological activity is not limited to their provitamin properties. Due to their ability to participate in redox reactions, carotenes are increasingly considered as promising compounds in the prevention and correction of cardiovascular and neurodegenerative disorders, as well as in oncology and the treatment of various other diseases. Carotenoids are widely used in the manufacture of food additives and dyes, feed for aquaculture, farm animals and poultry, as well as in so-called nutraceuticals and cosmetics. When formulating optimal feeding rations, vitamin A nutrition is often considered separately due to its vital role in normal growth, development, maintenance and reproduction. The main precursor of vitamin A is β-carotene, which naturally enters the body exclusively via vegetable-based provender. However, since the carotene contained in plant raw materials is an unstable compound, the use of feed additives containing β-carotene becomes relevant. In industry, carotenoids can be produced either by chemical or biological synthesis. However, the majority of carotenoids – 80–90% – are obtained by chemical synthesis. At the same time, public demand for sustainable production dictates the need to find alternative approaches for obtaining this valuable commodity. The article provides an overview of the main biotechnological methods for the production of carotenes using various microorganisms, including microalgae, bacteria and fungi, as well as analysing the effect of culture conditions on the yield of target pigments.

Diversity, distribution, and bioprospecting potentials of carotenogenic yeast from mangrove ecosystem.

Microbial production of carotenoids has gained significant interest for its cost-effectiveness and sustainable nature. This study focuses on 47 red-pigmented yeasts isolated from sediments and plant parts of 13 species of mangrove trees. The relative abundance and distribution of these yeasts varied with plant species and plant parts. The highest number of red yeasts was associated with the mangrove plant Avicennia officinalis (32%). Notably, the leaves harbored the highest percentage (45%) of carotenogenic yeasts, and definite compartmentalization of these yeast species was noticed in mangrove plant parts. All the isolates were molecularly identified and they belonged to the genera of Rhodotorula, Rhodosporidiobolus, and Cryptococcus. The diversity of the pigmented yeasts isolated from A. officinalis was found to be the greatest. Among these strains, Rhodotorula mucilaginosa PV 8 was identified as the most potent producer of carotenoid pigment. Under optimized conditions of physical parameters -28°C, pH 5, and 15% salinity led to biomass production of 9.2 ± 0.12g/L DCW and a pigment yield of 194.78µg/g. The pigment produced by PV 8 was identified as β-carotene by thin layer chromatography (TLC) and Fourier transform infrared spectroscopy (FT-IR). This β-carotene demonstrated strong antioxidant activity. Moreover, the carotenoid displayed promising antibacterial activity against multidrug-resistant organisms, including Aeromonas sp. and Vibrio sp. In vitro studies revealed the probiotic traits of PV 8. The cytotoxicity of R. mucilaginosa PV 8 was assessed in the invertebrate model Artemia salina and the survival rate showed that it was non-toxic. Furthermore, the β-carotene from PV 8 demonstrated the ability to transfer its vibrant color to various food products, maintaining color stability even under varied conditions. This research underscores the potential of R. mucilaginosa PV 8, as a versatile and valuable resource for the production of carotenoids.

Enhancement of yellow pigments production via high CaCl2 stress fermentation of Monascus purpureus.

Monascus pigments (MPs) are a kind of natural ingredient fermented by Monascus spp., which contains three types of pigments: red, orange, and yellow ones. Monascus yellow pigments have a restricted yield and cannot meet industrial application. The method and mechanism of CaCl2 improving yellow pigments production by liquid fermentation of Monascus purpureus M8 were studied in order to overcome the low yield of yellow pigments produced by liquid fermentation. Changes in physiological and biochemical indicators explained the effects of CaCl2 on the production of Monascus yellow pigments from solid fermentation. The intracellular yellow pigments, orange pigments, and red pigments increased by 156.08%, 43.76%, and 42.73%, respectively, with 60g/l CaCl2 addition to culture medium. The amount of red and orange pigments reduced, while the proportion of yellow pigments increased and the relative peak area of intracellular yellow pigments accounted for a dominant 98.2%, according to thin layer chromatography and high performance liquid chromatography analyses. Furthermore, the influence of CaCl2 extended to the modulation of pigments synthesis-related gene expression in M8 strain. This modulation led to a pronounced upregulation in the expression of the yellow pigments synthesis-related gene, mppE, signifying a pivotal role played by CaCl2 in orchestrating the intricate machinery behind yellow pigments biosynthesis.

Synthesis of Copper Carbonate from Copper Waste Using the Hydrometallurgical Method

&lt;p&gt;Electronic waste in Indonesia continues to increase, electronic waste is categorized as B3 waste which can threaten the environment. Electronic waste contains metals that can berecovery namely 20% copper (Cu), 8% iron (Fe), 4% tin (Sn), 2% nickel (Ni), 2% lead (Pb), 1% zinc (Zn), 0.2% silver (Ag), 0.1% gold (Au) and 0.005% palladium (Pa). Copper can be used as a raw material for making pigments mountain blue. Pigment extraction from copper metal can be done using the hydrometallurgical method which is considered more environmentally friendly and economical. The hydrometallurgical method uses solvents in the liquid phase to dissolve copper metal from waste and convert it into the desired compound. The materials used to make mountain blue pigment are copper waste, sulfuric acid (H&lt;sub&gt;2&lt;/sub&gt;SO&lt;sub&gt;4&lt;/sub&gt;), sodium hydroxide (NaOH), sodium carbonate (Na&lt;sub&gt;2&lt;/sub&gt;CO&lt;sub&gt;3&lt;/sub&gt;), hydrogen peroxide (H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt;), and distilled water. Meanwhile, the materials used for pigment application are Carboxymethyl Cellulose (CMC) and titanium dioxide (TiO&lt;sub&gt;2&lt;/sub&gt;). In this process, washing or leaching will be carried out(leaching) namely a chemical concentration process to release ore impurities from a mineral by dissolving it using certain reagents. Factors that influence the metal leaching process are temperature and acid concentration. In this experiment, the hydrometallurgical method succeeded in processing electronic waste into a blue pigment (mountain blue). The average pigment yield mountain blue in this experiment it was 1.25 grams of montain blue/gram of copper. Furthermore, the average conversion of pigment mountain blue was 89.3%.&lt;/p&gt;

Insights into the synthesis, engineering, and functions of microbial pigments in Deinococcus bacteria.

The ability of Deinococcus bacteria to survive in harsh environments, such as high radiation, extreme temperature, and dryness, is mainly attributed to the generation of unique pigments, especially carotenoids. Although the limited number of natural pigments produced by these bacteria restricts their industrial potential, metabolic engineering and synthetic biology can significantly increase pigment yield and expand their application prospects. In this study, we review the properties, biosynthetic pathways, and functions of key enzymes and genes related to these pigments and explore strategies for improving pigment production through gene editing and optimization of culture conditions. Additionally, studies have highlighted the unique role of these pigments in antioxidant activity and radiation resistance, particularly emphasizing the critical functions of deinoxanthin in D. radiodurans. In the future, Deinococcus bacterial pigments will have broad application prospects in the food industry, drug production, and space exploration, where they can serve as radiation indicators and natural antioxidants to protect astronauts' health during long-term space flights.