Exploring the Functional Properties and Nutritional Values of Colored Oyster Mushrooms Species (Pleurotus, Agaricomycetes): A Review.

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.

Purified Pyropia yezoensis Pigment Extract-Based Tandem Dye Synthesis.

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.

An antioxidant hydrogel dressing with wound pH indication function prepared based on silanized bacterial nanocellulose crosslinked with beet red pigment extract.

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.

Identification and quantification of pigments in plant leaves using thin layer chromatography-Raman spectroscopy (TLC-Raman).

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.

Pulvinic Acid Derivative Pigments in Lanmaoa asiatica and L. macrocarpa.

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.

Exploring colorant production by amazonian filamentous fungi: Stability and applications.

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.

Regulation of the pigment production by changing Cell morphology and gene expression of Monascus ruber in high-sugar synergistic high-salt stress fermentation.

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.

Progress on the Extraction, Separation, Biological Activity, and Delivery of Natural Plant Pigments.

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.

A Review of the Chemistry and Biological Activities of Natural Colorants, Dyes, and Pigments: Challenges, and Opportunities for Food, Cosmetics, and Pharmaceutical Application.

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, ß-carotene, ß-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.

Yellow pigments produced by oxidative oligomerization of dihydrochalcone glucoside and the reaction mechanism.

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.

Valorization of pineapple peel waste for fungal pigment production using Talaromyces albobiverticillius: Insights into antibacterial, antioxidant and textile dyeing properties.

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.

Nanoemulsion containing Yellow Monascus pigment : Fabrication, characterization, storage stability, and lipase hydrolytic activity in vitro digestion.

The natural pigment of monascus is favored by human for its special coloring and physiological activity, and its development and application have attracted much attention. In this study, a novel corn oil-based nanoemulsion encapsulated with Yellow Monascus Pigment crude extract (CO-YMPN) was successfully prepared via the phase inversion composition method. The fabrication and stable conditions of the CO-YMPN including Yellow Monascus pigment crude extract (YMPCE) concentration, emulsifier ratio, pH, temperature, ionic strength, monochromatic light and storage time were investigated systemically. The optimized fabrication conditions were the emulsifier ratio (5:3 ratio of Tween 60 to Tween 80) and the YMPCE concentration (20.00% wt%)). Additionally, the DPPH radical scavenging capability of the CO-YMPN (19.47 ± 0.52%) was more excellent than each YMPCE or corn oil. Moreover, the kinetic analysis results based on Michaelis-Menten equation and constant revealed that CO-YMPN could improve lipase hydrolysis capacity. Therefore, the CO-YMPN complex had excellent storage stability and water solubility in the final water system, and the YMPCE showed brilliant stability.

Complexation of anthocyanins, betalains and carotenoids with biopolymers: An approach to complexation techniques and evaluation of binding parameters.

Natural pigments are bioactive compounds that can present health-promoting bioactivities in the human body. Due to their strong coloring properties, these compounds have been widely used as color additives as an alternative to artificial colorants. However, since these pigments are unstable under certain conditions, such as the presence of light, oxygen, and heat, the use of complexation and encapsulation techniques with biopolymers is in demand. Moreover, some functional properties can be achieved by using natural pigments-biopolymers complexes in food matrices. The complexation and encapsulation of natural pigments with biopolymers consist of forming a complex with the aim to make these compounds less susceptible to oxidative and degrading agents, and can also be used to improve their solubility in different media. This review aims to discuss different techniques that have been used over the last years to create natural pigment-biopolymers complexes, as well as the recent advances, limitations, effects, and possible applications of these complexes in foods. Moreover, the understanding of thermodynamic parameters between natural pigments and biopolymers is very important regarding the complex formation and their use in food systems. In this sense, thermodynamic techniques that can be used to determine binding parameters between natural pigments and potential wall materials, as well as their applications, advantages, and limitations are presented in this work. Several studies have shown an improvement in many aspects regarding the use of these complexes, including increased thermal and storage stability. Nonetheless, data regarding the biological effects on the human body and the sensory acceptance of natural pigments-biopolymers complexes in food systems are scarce in the literature.

The chromogenic mechanism of natural pigments and the methods and techniques to improve their stability: A systematic review.

Pigments have become a very important part of food research, not only adding sensory properties to food, but also providing functional properties to the food system. In this paper, we review the source, structure, modification, encapsulation and current status of the three main types of natural pigments that have been studied in recent years: polyphenolic flavonoids, tetraterpenoids and betaines. By examining the modification of pigment, the improvement of their stability and the impact of new food processing methods on the pigments, a deeper understanding of the properties and applications of the three pigments is gained, the paper reviews the research status of pigments in order to promote their further research and provide new innovations and ideas for future research in this field.

Absolute configuration of azaphilones from Monascus kaoliang KB9 and solvent effects on their keto and enol forms.

Monascus fermented rice, also known as red yeast rice, exhibits a broad spectrum of biological activities due to its chemical constituents, such as monacolins and azaphilone pigments. Here, we cultured Monascus kaoliang KB9 in a liquid malt medium instead of on rice as a carbon source. Eleven known compounds (1-11) containing azaphilones and their early intermediate were isolated and identified. However, this was the first time that angular tricyclic azaphilones, monasfluols A (4) and B (7), acetyl-monasfluol A (5) and monasfluore A (6), were isolated from this species. Interestingly, all isolated tricyclic azaphilones existed exclusively in enol form in CD3OD, as evidenced by NMR spectroscopy. The absolute configuration of compounds 4-7 was also first experimentally identified based on ECD spectroscopy combined with conformational analyses using computational techniques. The assigned stereochemistry of Monascus azaphilones in this work provides essential structural information that will benefit future biological and pharmaceutical investigations.

Combination of 1H and 13C NMR for quantitative analysis of the orange pigments produced by Monascus kaoliang KB9.

Two orange pigments, rubropunctatin (1) and monascorubrin (2), along with the yellow pigments, monascin (3) and ankaflavin (4), were isolated from M. kaoliang KB9-fermented rice, also known as red yeast rice. The orange pigments exhibit a broad spectrum of biological activities and appeared to be the major components of this fermented rice. In this work, quantitative 1H NMR (qHNMR) and 13C NMR experiments were used to determine the amounts of the two orange pigments in a crude extract in which most of the 1H NMR signals of the two compounds were indistinguishable. The quantitative values obtained by NMR techniques were found to be similar to those obtained by HPLC. Thus, the combined qHNMR with 13C experiment described in this work could be further developed to quantifying Monascus pigments or other invaluable natural products when qHNMR alone is insufficient for quantitative analysis.

Azaphilones from the Endophyte Diaporthe sp. and Their Toxicity.

Chemotherapy and targeted therapies are increasingly used as conventional means to control tumor growth and prolong survival. Patient treated with anti-neoplastic agents experience severe side effects, especially those cytotoxic chemotherapies. Exploring chemo agents with less side effects is the hot spot of anticancer research. In this study, three azaphilone derivatives (chaetoviridin A (1), chaetoviridin E (2) and chaetomugilin D (3)) were isolated from the endophyte of the plant Anoectochilus roxburghii (Wall.) Lindl, their structures were elucidated by NMR. The toxicity of these compounds was evaluated by zebrafish model. The results show that these compounds had no toxicity against zebrafish. These compounds may act as safe anticancer drug leads according to this result. These three azaphilone derivatives were first time reported isolated from Diaporthe species which mainly used to isolate from Chaetomium species.

Naturally Occurring Partially Reduced Perylenequinones from Fungi.

This Review provides a critical analysis of the literature covering the naturally occurring partially reduced perylenequinones (PQs) from fungi without carbon substituents (which can be named class A perylenequinones) and discusses their structures, stereochemistry, biosynthesis, and biological activities as appropriate. Perylenequinones are natural pigments with a perylene skeleton produced by certain fungi, aphids, some plants, and animal species. These compounds display several biological activities, e.g., antimicrobial, anti-HIV, photosensitizers, cytotoxic, and phytotoxic. It describes 36 fungal PQs and cites 81 references, covering from 1956 to August 2022.

Formation of Azaphilone Pigments and Monasnicotinic Acid by the Fungus Aspergillus cavernicola.

Due to the ever-increasing demand for healthy and safe food, much attention has been gained by natural food colorants. This study showed the culture fluid extract of the fungus Aspergillus cavernicola VKM F-906 to contain red pigment and monasnicotinic acid (MNA) in predominant amounts. The structure of the pigment corresponded to cis-cavernamine (red pigment, RP). Two tautomers, NH and OH forms, in rapid equilibrium were present in a solution of RP. The critical factors for RP to form were the presence of NH4+ salt and pH 6.3-6.5. In vitro experiments showed that MNA was synthesized from RP as a result of chemical transformations without the participation of enzymes. In this case, the main influence on the reaction rate is exerted by the pH of the medium, which is associated with the keto-enol tautomerism of RP in solution. The culture broth extract and MNA exhibited antifungal activity against Fusarium fungi.

Pigment produced from Arcopilus aureus isolated from grapevines: Promising natural yellow colorants for the food industry.

Interest in the use of natural non-toxic pigments by the food industry has grown. Some filamentous fungi are producers of natural pigments that are more stable at temperature and pH than other pigments also classified as natural, such as those produced by plants. Production potential of natural pigments by endophytic fungi from grapevines was evaluated. Arcopilus aureus was selected as a potential source for a yellow pigment, which was characterized and tested for stability to variations in temperature and pH. Components, cochlioquinol II and riboflavin, were detected, which has not previously been reported in A. aureus. The pigment was stable and showed increased absorption at lower / acidic pH. These results provide information on the potential of this fungus and a yellow pigment for the first time, which can be used for further development and industrial application.