Brown Pigment Research Articles

Rapid and efficient synthesis of energy-saving cool pigments and environmental restoration materials using rare earth secondary resources

This paper proposes a method for the short-process recovery and reuse of rare earth secondary resources. Low-value rare earth polishing powder waste (WP), trichromatic phosphor waste (WT), NdFeB permanent magnetic waste (WN), and SmCo permanent magnetic waste (WS) were used as the raw materials. Based on the concept of combinatorial chemistry, energy-efficient cool pigments and environmental remediation materials were synthesized by a solid-phase method. The results showed that the synthesized materials had fluorite-type and garnet-type structures. In terms of cool pigments, doping with different rare earth permanent magnets can enrich the color (including yellow, green, brown, gray, and blue) and cause fluctuations in the near-infrared (NIR) reflectance (59.05–99.54 %) and NIR solar reflectance (55.32–95.64 %). Yellow fluorite-type pigments (WP: WT = 1:1) have the highest NIR reflectance (R = 99.54 %), while brown fluorite-type pigments (WP: WN = 1:0.1) and blue garnet-type pigments (WP:WS = 1:0.1) have relatively high NIR reflectance, 88.18 % and 59.30 %, respectively. The synthesized pigments possessed better chemical stabilities and thermal insulation performance. In terms of environmental remediation materials, the adsorption capacities of fluorite-type materials for F− and PO43− can reach 84.03 mg/g and 85.3 mg/g, respectively. In summary, materials synthesized from rare earth waste exhibit excellent potential for use in energy-efficient wastewater treatment and promote the sustainable utilization of secondary rare earth resources.

Bridelia scandens Wild.– An Pharmacognstic Overview

Abstract: Pharmacognosy is the study of naturally occurring biological substances, principally those derived from plants that find use in medicine. The word 'pharmacognosy' is derived from the Greek 'pharmacon', 'a drug', and gignosco, 'to acquire a knowledge of'. As late as the beginning of the 20th century, the subject had developed mainly on the botanical side, being particularly concerned with the description and identification of drugs, both in the whole state and in powder, and with their history, commerce, collection, preparation and storage. The plant selected for the present study - Bridelia scandens Wild. of the family Euphorbiaceae, is yet another folklore medicinal plant which is widely used in some parts of Karnataka in treating the disease Amavata by the local tribal people and villagers. Here an attempt is made to validate plant pharmacognostically Bridelia scandens Wild. is a large, woody, evergreen, scandent shrub with pendant branches large defluxed spines abundantly seen in western ghats. Bark grey, hard, deeply fissured; leaves elliptic, obtuse entire, thinly curvaceous; flowers greenish yellow, in dense axillary heads arranged in paniculate leafy spikes; drupes ovoid, bluish black, succulent, smooth. Upper epidermis shows no stomata and lower epidermis shows mostly ranuculaceous stomata. Transverse section of the petiole is almost circular with a narrow groove at the upper side and wavy margin with plenty of non-glandular trichomes. T.S. of the leaf shows a dorsivertral outline; vascular bundles are circular and similar to that of dicot stem. Microscopic study of the leaf powder showed, trichomes, fragments of lower epidermis with stomata, sclerenchyma fibers, crystals, chloroplast, vein fragments, spiral vessels and orange-reddish to brown pigments

Morphological Characterization of Native Isolates of Hypocreale Fungi Metarhizium rileyi (Farl.) Samson from Maize Fall Armyworm

The Present studies indicates the collection of entomopathogenic fungi from the roving survey in Northeastern region of Karnataka, India to know the diversity of M. rileyi distribution and also its growth pattern. Different morphological parameters used for describing the growth pattern which indicates diversity and uniqueness of M. rileyi i.e., colony colour which was white during initial stage and then during sporulating stage the colour changed into malachite green colour. The conidiophores were in compact patches. Conidia were aseptate, hyaline, round or ovoid in shape and elongate by forming chains. Conidiophores were short, which bears round to ovoid aseptate conidia in different isolates. The conidia size on its ratio found that, the highest size ratio was recorded in UASRBC Mr-20 2.19 then remaining isolates which has shown less than 2.0. The radial growth found only in Mr-20 and Mr-22nd Isolates, colony diameter ranged from 0.3 to 2.23 cm, concentric rings of colonies found in all the isolates except Mr-19 and Mr-20th isolates. The colony surface layer was white cottony growth to pale yellow color was found in all the isolates, the colony pigmentation in most of the isolates was light brown colored pigmentation. The growth appearance was irregular patchy growth was observed in most of the isolates. Among six different isolates the highest width was recorded in isolate UASRBC Mr-20 (6.46) followed by UASRBC Mr-22 (5.73) which was significantly superior than remaining isolates. The highest colony diameter was recorded in UASRBC Mr-18 (19 mm).

Optix regulates nanomorphology of butterfly scales primarily via its effects on pigmentation

Previous studies have shown that Optix regulates lower lamina thickness and the type of pigment that is produced in wing scales of a few butterfly species. However, the role of Optix in regulating pigment production across species, and in regulating additional aspects of scale morphology remains to be investigated. By combining microspectrophotometry, scanning electron microscopy, and focused ion beam technology on wild-type and Optix Bicyclus anynana crispants, we show that Optix regulates the production of orange pigments (ommochromes), represses the production of brown pigments (melanins), and regulates the morphology of the lower and upper surface of orange scales. Our findings suggest a conserved role of Optix as a switch gene that activates ommochrome and represses melanin synthesis across butterflies. By comparing these effects with other mutations, where only melanin is removed from scales, we propose that pigmentary changes, alone, affect the way that chitin polymerizes within a scale, changing lower lamina thickness as well as multiple intricate structures of the upper surface.

Siderosis of the esophagus

This publication describes a rare clinical case of esophageal siderosis. The patient was found to have flat irregularly shaped superficial scars with areas of hyperpigmentation of the esophageal mucosa in a dark color. It is known from the anamnesis that she has long suffered from iron deficiency anemia and takes iron preparations. A conclusion was made about the defeat of the esophageal mucosa by iron sulfate preparations - esophageal siderosis. The endoscopic conclusion was confirmed by a pathomorphological study - a few cells with brown pigment in the cytoplasm were found in the subepithelial connective tissue - a picture of siderosis

Addition of Modifying Agents vs Basic Functional Properties of Moldings Made of ABS

Unconventional injection methods include i.e. blowing injection that allows for production of moldings with a lower weight while maintaining mechanical properties of detail. Due to the fact that most polymers are dyed at the processing stage, it is important to examine the simultaneous effect of blowing and colorbatch, as well as variable processing conditions, on the functional properties of moldings made of the most popular construction material, i.e. ABS. Samples were made of ABS polymer without and with the addition of a colorbatch containing brown pigment on ABS matrix, and blowing agent. Variable processing conditions were: mold and injection temperature, holding pressure and time. Other parameters were constant. Samples were tested for basic functional properties such as color, gloss, mass, density and thickness. Moldings produced with a higher blowing agent content and a higher injection temperature were characterized by lower mass. No significant influence of processing parameters and content of colorbatch on mass of samples was found. Blowing agent has no significant impact on thickness of moldings, regardless of processing conditions. Addition of a colorbatch influenced samples’ gloss. Increase in colorbatch and blowing agent content and mold temperature allow to obtain moldings with a higher surface gloss. Colorbatch also changed color of samples – a decrease in luminance L even by about 40% and great changes in parameters “a” and slight changes in parameter “b”. It was found that blowing agent content had the greatest influence on density of moldings. Injection temperature and colorbatch, do not significantly affect density of moldings.

Blastococcus brunescens sp. nov., a member of the Geodermatophilaceae isolated from sandstone collected from the Sahara Desert in Tunisia.

The taxonomic position of strain BMG 8361T, isolated from sandstone collected in the Sahara Desert of Southern Tunisia, was refined through a polyphasic taxonomic investigation. Colonies of BMG 8361T were pale-orange coloured, irregular with a dry surface and produced a diffusible pink or brown pigment depending on media. The Gram-positive cells were catalase-positive and oxidase-negative. The strain exhibited growth at 10-40 °C and pH values ranging from 5.5 to 9.0, with optima at 28-35 °C and pH 6.5-8.0. Additionally, BMG 8361T demonstrated the ability to grow in the presence of up to 1 % NaCl (w/v) concentration. The peptidoglycan of the cell wall contained meso-diaminopimelic acid, glucose, galactose, xylose, ribose, and rhamnose. The predominant menaquinones consisted of MK-9(H4) and MK-9. The main polar lipids were phosphatidylcholine, phosphatidylinositol, glycophosphatidylinositol, diphosphatidylglycerol, phosphatidylethanolamine, and two unidentified lipids. Major cellular fatty acids were iso-C16 : 0, iso-C16 : 1 h, and C17 : 1 ω8c. Phylogenetic analyses based on both the 16S rRNA gene and whole-genome sequences assigned strain BMG 8361T within the genus Blastococcus. The highest pairwise sequence similarity observed in the 16S rRNA gene was 99.5 % with Blastococcus haudaquaticus AT 7-14T. However, when considering digital DNA-DNA hybridization and average nucleotide identity, the highest values, 48.4 and 86.58 %, respectively, were obtained with Blastococcus colisei BMG 822T. These values significantly undershoot the recommended thresholds for establishing new species, corroborating the robust support for the distinctive taxonomic status of strain BMG 8361T within the genus Blastococcus. In conjunction with the phenotyping results, this compelling evidence leads to the proposal of a novel species we named Blastococcus brunescens sp. nov. with BMG 8361T (=DSM 46845T=CECT 8880T) as the type strain.

Streptomyces profundus sp. nov., a novel marine actinobacterium isolated from deep-sea sediment of Madeira Archipelago, Portugal.

A novel strain, MA3_2.13T, was isolated from deep-sea sediment of Madeira Archipelago, Portugal, and characterized using a polyphasic approach. This strain produced dark brown soluble pigments, bronwish black substrate mycelia and an aerial mycelium with yellowish white spores, when grown on GYM 50SW agar. The main respiratory quinones were MK-10(H4), MK-10(H6) and MK-10(H8). Diphosphatidylglycerol, phosphatidylethanolamine, three unidentified phospholipids and two glycophospholipids were identified as the main phospholipids. The major cellular fatty acids were iso-C16 : 1, iso-C16 : 0, anteiso-C17 : 1 and anteiso-C17 : 0. Phylogenetic analyses based on 16S rRNA gene showed that strain MA3_2.13T is a member of the genus Streptomyces and was most closely related to Streptomyces triticirhizae NEAU-YY642T (NR_180032.1; 16S rRNA gene similarity 97.9 %), Streptomyces sedi YIM 65188T (NR_044582.1; 16S rRNA gene similarity 97.4 %), Streptomyces mimosae 3MP-10T (NR_170412.1; 16S rRNA gene similarity 97.3 %) and Streptomyces zhaozhouensis NEAU-LZS-5T (NR_133874.1; 16S rRNA gene similarity 97.0 %). Genome pairwise comparisons with closest related type strains retrieved values below the threshold for species delineation suggesting that strain MA3_2.13T represents a new branch within the genus Streptomyces. Based on these results, strain MA3_2.13T (=DSM 115980T=LMG 33094T) is proposed as the type strain of a novel species of the genus Streptomyces, for which the name Streptomyces profundus sp. nov. is proposed.

Diffuse hyperpigmentation with guttate hypopigmentation: a new pigmentary disorder.

Diffuse hyperpigmentation with guttate hypopigmentation (DHGH) is a new acquired pigmentary disorder. Only a few cases have previously been reported in the Chinese population, in Chinese. To summarise the clinical, dermoscopic, and histopathological findings of DHGH in the English literature, to improve the recognition and management of this condition. This was a retrospective study to summarise the clinical, dermoscopic, and pathological findings of nine cases of DHGH. All nine patients with DHGH were female. The age at onset varied from 6 to 24 years (median 17 years). Patients were generally in good health without systemic disease. The lesions were often generalised to the trunk and extremities without any discomfort. Typical lesions were characterised by multiple uniform hypopigmented spots, 2-5mm in diameter, irregularly distributed over diffuse hyperpigmentation. Dermoscopy revealed multiple blurred patchy areas of brownish pigmentation, sparse linear and dotted vessels, and perifollicular pigmentation on a white to bright white background, surrounded by brown hyperpigmentation. Histopathological findings included mild abnormal pigment of the epidermis, focal vacuolar degeneration of the basal cells, mild pigment incontinence and perivascular lymphocytic infiltration in the dermis. DHGH is a new entity with distinctive clinical manifestations that differ from those of other known pigmentary disorders. So far, DHGH has only been reported in the Chinese population. It may not be uncommon and has not received much attention due to the few reports. The aetiology and pathogenesis of DHGH are still unknown and require further investigation.

Leaf Spot caused by Alternaria tenuissima on Rhamnella franguloides in China.

The small tree species Rhamnella franguloides, belonging to the genus Rhamnella in the tribe Rhamneae Hook. f. of Rhamnaceae (Hauenschild et al. 2016), is an important medicinal plant commonly used for making tea in China. In August 2023, leaf spot symptoms were observed on R. franguloides in Shangyao county, Yantai, Shandong, China, with a disease incidence of 45-65%. Initially appearing as small dark brown spots on the tip lesions, they later expanded and merged into irregular-shaped brown necrotic lesions with yellowish halos. To isolate pathogen, 20 symptomatic tissue fragments (5 × 5 mm) from ten sampling randomly plants were surface sterilized, placed on potato dextrose agar (PDA) plates, and incubated at 25°C in darkness for 3 days to obtain colonies.10 purified isolates with similar morphological characteristics were obtained by single-spore isolation from the colonies. The representative isolate MR13 was chosen for morphological and molecular analysis. The colonies On PDA medium initially appear as a circular yellow-brown ring with white round margins, ultimately turning into olive green with fluffy aerial hyphae. The conidiophores displayed brown pigmentation, solitary or branched, producing abundant short chains of conidia. The conidia were typically obclavate to obpyriform or ellipsoid in shape, 22.5-64.5 × 12.5-23.6μm in size, with a short conical beak at the apex, zero to three longitudinal septa and one to five transverse septa. Based on cultural and morphological characteristics, the fungus was identified as Alternaria spp (Simmons 2007). Due to morphological traits, five genes (the internal transcribed spacer [ITS], actin [ACT], plasma membrane ATPase [ATP], Alternaria major allergen [Alt a1] and histone 3 [H3]) form MR13 were amplified using primer pairs ITSI / ITS4, ACTDF1/R1, ATPDF1 / ATPDRI, Alt-for / Alt-rev, and H3-1a/1b, respectively (Hong et al. 2005; Lawrence et al. 2013; Lousie and Donaldson 1995). BLASTn analysis failed to confirm the identification of MR13 species based on ITS, ACT, ATP and Alt a1(ITS, OR668512; ACT, OR676918; ATP, OR676917; Alt a1, OR676919). The phylogenetic tree showed that it was closely related to Alternaria alternate, A. tenuissima, and A. destruens. The H3 sequence (OR676920) exhibited 100% similarity to A. tenuissima (OR485421). The phylogenetic tree constructed solely with H3 further confirmed MR13 as A. tenuissima. Pathogenicity tests were conducted by introducing the fungus onto healthy R. franguloides leaves in the field. Fifty leaves (five per plant) were treated with a 20ml suspension containing around 1x10^4 spores/ml, while an equal number of control samples were sprayed with distilled water. Transparent plastic bags were used to cover the treated leaves for 48 hours and maintain humidity. After fourteen days of inoculation, consistent leaf spotting symptoms were observed. In contrast, the control leaves showed no sign of infection. The fungal pathogen was successfully reisolated and identified as A. tenuissima through morphological and sequence analysis, fulfilling Koch's postulates. To our knowledge, this is the first report of A. tenuissima causing leaf spot disease on R. franguloides in China. Identifying the disease's causal agent is crucial for developing effective management strategies.

Trichoscopic Features of Scalp Discoid Lupus Erythematosus versus Lichen Planopilaris: A Systematic Review.

Lichen planopilaris (LPP) and discoid lupus erythematosus (DLE) are primary scarring alopecias that pose diagnostic challenges clinically, where trichoscopy features may provide benefit in delineating these two cicatricial alopecia, and also helps in assessing the evolution and therapeutic response. To date, there are few reviews on dermoscopic findings in differentiating these two alopecias. A systematic literature review was conducted using the PubMed and Google Scholar databases. The search terms included for scalp DLE were 'lupus' OR 'discoid lupus' OR "scalp lupus" and for scalp LPP were "lichen planopilaris" OR "scalp follicular lichen planus" OR "lichen planus follicularis" and were combined with "dermoscopy" OR "dermatoscopy" OR "videodermoscopy" OR "video dermatoscopy" OR "trichoscopy". The differences in the prevalence of dermoscopic features in scalp DLE and LPP were calculated using the Chi-square test. Of 52 articles, 36 (17 LPP, 19 DLE) were eligible for quantitative analysis. We found predominant peripilar tubular casts and perifollicular erythema with the presence of arborizing vessels in the vicinity of these changes, indicating early LPP. In contrast, follicular red dots, speckled brown pigmentation, and hair diameter variability indicated active DLE. Shiny white areas were common in both the groups in late stages. The target pattern of distribution of blue-grey dots, milky red areas, and irregular white fibrotic dots were seen in LPP, and pink-white background, follicular plugs, perifollicular and interfollicular scale, rosettes, chrysalides, and red spider on yellow dots were detected in DLE. Features such as yellow dots and blue-grey structureless areas were nonspecific and did not have a major role in differentiating DLE from LPP. This article provides a comprehensive review of the literature and delineates the trichoscopic differences and peculiarities of scalp DLE and LPP, including the correlation of dermoscopic features with histopathological findings.

Influence of Air Drying, Freeze Drying and Oven Drying on the Biflavone Content in Yellow Ginkgo (Ginkgo biloba L.) Leaves

Drying herbs is a crucial method for stabilizing and preserving their essential properties and bioactive compounds. Although freeze drying is the preferred method for most herbs, it is expensive due to high energy consumption and operating costs. Biflavonoids are dimeric flavonoids that have recently been recognized as potential molecules possessing biological activities, such as antiviral and antimicrobial activity, and as effective molecules for the treatment of neurodegenerative and metabolic diseases and for cancer therapies. In this study, we performed a comparative analysis of freeze drying, air drying and oven drying to evaluate their effects on biflavonoid content in yellow ginkgo leaves (Ginkgo biloba L.). After drying, we performed spectrophotometric analysis to determine the browning index, pigments, phenolic compounds and antioxidant activity, while HPLC-DAD was used for the identification and quantification of individual biflavones (amentoflavone, bilobetin, ginkgetin, isoginkgetin and sciadopitysin). The most abundant biflavonoids were isoginkgetin and bilobetin, the amounts of which exceeded 1000 µg/g dw in all leaf samples. They were followed by ginkgetin and sciadopitysin, the amounts of which were about 30% lower. The drying method did not influence biflavone content or the total carotenoids, total polyphenols and total flavonoids. Consequently, our study suggests that all three methods may be used for the preparation of yellow ginkgo leaves as a source of biflavones and other bioactive compounds.

First Report of Fusarium culmorum Causing Crown Rot on Wheat in Jordan

First Report of <i>Fusarium culmorum</i> Causing Crown Rot on Wheat in Jordan

Smoking-Related Interstitial Fibrosis and Smoker's Macrophages.

Smoking-related interstitial lung diseases (SRILDs) are a group of heterogeneous diffuse pulmonary parenchymal diseases associated with tobacco exposure. Smoking-related interstitial fibrosis (SRIF) is relatively recent, a pathologically defined form of SRILDs. SRIF is characterized by the accumulation of macrophages in the alveolar spaces, which is associated with interstitial inflammation and fibrosis. The macrophages frequently contain light brown pigment and are called 'smoker's macrophages'. Patients with SRIF who have clinical evidence of interstitial lung disease are most commonly relatively young, heavy smokers with abnormalities on chest computed tomography showing ground-glass opacities, peripheral consolidation, and reticulation. Although SRIF is caused by cigarette smoking, the exact pathophysiological mechanisms by which smoking causes this type of interstitial fibrosis remain unknown. The degree of fibrosis and appearance of macrophage aggregates are important points of distinction when evaluating and diagnosing SRIF. Macrophage heterogeneity, particularly the activation and function of monocyte-derived alveolar macrophages (Mo-AMs) and interstitial macrophages (IMs), has important implications for the pathogenesis of SRIF and developing treatments. Further researches focused on smoker's macrophages are needed to understand of the pathogenesis of SRIF.

The Effects of Bee Additives on the Physico-Chemical and Antioxidant Properties of Rapeseed Honey

The aim of this paper was to conduct a comparative analysis of rapeseed honeys enriched with various bee products: propolis (1%), bee bread (2%), and bee pollen (5%). The parameters examined included water content, electrical conductivity, pH, free acid content, brown pigment content, color analysis, total polyphenol content, sugar content, and antioxidant activity using the DPPH method. The results demonstrated compliance with Polish requirements for commercial honey quality, with one exception: honey containing 1% propolis, which had a water content of 21.15%. The analysis results indicated that the tested bee products exhibited strong antioxidant properties, with rapeseed honey enriched with 5% bee pollen showing the highest antioxidant activity and content.

Investigation of Cryptococcus Colonization and Mating Genotype in Environmental Samples

Cryptococcus species are fungal pathogens that pose a serious threat to human life and can cause meningoencephalitis in immunocompromised and healthy individuals. It was estimated that approximately 112000 people die every year due to cryptococcal-related infections all over the world, especially in immunocompromised individuals. Cryptococcus species can be found in soil, bat dung, pigeon droppings, and various tree species in addition to humans. Despite the majority of Cryptococcus species being haploid opportunistic human pathogens, it is known that the ability to undergo sexual reproduction plays a significant role in the expansion of species distribution and the increase in virulence. In Cryptococcus species, sexual reproduction is governed by the mating genotype gene region called the MAT locus. Pathogenic Cryptococcus species have two mating types (MATa and MATα), defined by the presence of one of two alternative alleles at a single MAT locus. In this study, various tree species (eucalyptus, olive and carob) in a total of seven regions in Mersin (Gülnar, Göksu, Narlıkuyu, Ayaş, Kızkalesi, and Tarsus) and Hatay provinces were examined to detect Cryptococcus species. The aim of this study was to determine the environmental distribution and sexual genotypes of Cryptococcus species in these regions. In the present study, samples were collected from a total of 750 trees, including olive, eucalyptus, and carob trees. The samples were incubated on Staib agar medium containing 0.1% biphenyl and 0.5% chloramphenicol. Colonies that formed brown pigment were identified as C.neoformans using conventional and molecular methods. The sexual genotypes were determined by comparing the lengths of the STE20 gene from the isolates compared with those of reference C.neoformans strains. Growth was observed in 97 (12.9%) of 750 samples collected from eucalyptus (n= 236), olive (n= 303) and carob (n= 211) trees. All 97 isolates were determined to be C.neoformans var. grubii. The highest positivity was found in Narlıkuyu (78.2%), and from carob (9.4%) and olive (3.5%) trees. Cryptococcus species was not detected in any of the samples derived from eucalyptus trees. Based on the lengths of the STE20 gene, it was determined that all C.neoformans var. grubii isolates were in the MAT Aα genotype. The data obtained regarding the environmental distribution of Cryptococcus species and the distribution of genes involved in sexual reproduction are believed to provide valuable guidance in terms of the potential clinical implications of environmental Cryptococcus hotspots and regional species characteristics in our country.

Bioproduction and optimization of newly characterized melanin pigment from Streptomyces djakartensis NSS-3 with its anticancer, antimicrobial, and radioprotective properties

BackgroundMelanin is a natural pigment that is considered a promising biomaterial for numerous biotechnological applications across several industries. Melanin has biomedical applications as antimicrobial, anticancer, and antioxidant properties. Additionally, in the pharmaceutical and cosmetic industries, it is used in drug delivery and as a radioprotective agent. Also, melanin has environmental uses in the fields of bioremediation and the food industry. The biosynthesis of melanin pigment is an area of interest for researchers due to its multifunctionality, high compatibility, and biodegradability. Therefore, our present work is the first attempt to characterize and optimize the productivity of melanin pigment from Streptomyces djakartensis NSS-3 concerning its radioprotection and biological properties.ResultsForty isolates of soil actinobacteria were isolated from the Wadi Allaqui Biosphere Reserve, Egypt. Only one isolate, ACT3, produced a dark brown melanin pigment extracellularly. This isolate was identified according to phenotypic properties and molecular phylogenetic analysis as Streptomyces djakartensis NSS-3 with accession number OP912881. Plackett–Burman experimental design (PBD) and response surface methodology (RSM) using a Box-Behnken design (BBD) were performed for optimum medium and culturing conditions for maximum pigment production, resulting in a 4.19-fold improvement in melanin production (118.73 mg/10 mL). The extracted melanin pigment was purified and characterized as belonging to nitrogen-free pyomelanin based on ultraviolet–visible spectrophotometry (UV–VIS), Fourier transform infrared (FT-IR), Raman spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and NMR studies. Purified melanin demonstrated potent scavenging activity with IC50 values of 18.03 µg/mL and revealed high potency as sunscreens (in vitro SPF = 18.5). Moreover, it showed a nontoxic effect on a normal cell line (WI38), while it had a concentration-dependent anticancer effect on HCT116, HEPG, and MCF7 cell lines with IC50 = 108.9, 43.83, and 81.99 µg/mL, respectively. Also, purified melanin had a detrimental effect on the tested MDR bacterial strains, of which PA-09 and SA-04 were clearly more susceptible to melanin compared with other strains with MICs of 6.25 and 25 µg/mL, respectively.ConclusionOur results demonstrated that the newly characterized pyomelanin from Streptomyces djakartensis NSS-3 has valuable biological properties due to its potential photoprotective, antioxidant, anticancer, antimicrobial, and lack of cytotoxic activities, which open up new prospects for using this natural melanin pigment in various biotechnological applications and avoiding chemical-based drugs.

Clinicopathological, Immunohistochemical, and Molecular Characteristics of Pigmented Microcystic Chromophobe Renal Cell Carcinoma with Favorable Prognosis.

Background. Pigmented microcystic chromophobe renal cell carcinoma (RCC) is a subtype of chromophobe RCC. Its distinct histopathologic features are microcystic and microtubular pattern, pigmentation, and microcalcifications. Pigmented microcystic chromophobe RCC has ultrastructure, immunophenotypic structure, and molecular results similar to chromophobe RCC. Methods. We report five tumors of pigmented microcystic chromophobe RCC. Morphological observation and immunohistochemical examination were performed, and clinical and molecular features were analyzed. Results. Microscopically, all five tumors showed brown pigmentation, microcystic, and tubular cystic structures, one tumor presented microscopic calcifications. All tumors were positive for EMA, AE1/AE3, PAX8, KRT7, KIT (CD117), claudin 7, KRT8, and E-cadherin, and three tumors expressed P504S. All tumors were negative for vimentin, CA9, KRT20, TFE3, TFEB, Melan-A, HMB45, FH, SDHB, and GATA3. Ki-67 index varied from less than 1% to 2%. In three tumors, next-generation sequencing of the 688 gene was performed, the results found gene variants with potential clinical significance such as JMJD1C, MYCL, TP53, PI3KCA, KRAS, APC, GLI1, LRRK2, and gene variants with unclear clinical significance such as NTRK1 and RAD50; All patients remained alive over a follow-up period of 8-46 months without tumor recurrence and sarcomatoid transformation. Conclusions. Pigmented microcystic chromophobe RCC has a relatively benign biological behavior, and distant metastases and sarcomatoid transformation are rare. This overview of five additional tumors of pigmented microcystic chromophobe RCC offers further insight into this special subtype of chromophobe RCC.

Effect of Pigment-Acrylic Binder Ratio on the Surface and Physical Properties of Resin Finished Leather

The current study attempts to investigate the surface phenomenon and physical characteristics of leather finished with brown pigment and different types of acrylic binders. Using the contact angle measurements of three different liquids on the above finished leathers and films, the surface energy and work of adhesion were evaluated. The pigment to acrylic binder ratio (PABR) for best adhesion of finish film on the leather surface was optimized using the contact angle goniometer. Different types of acrylic binder films were coated and their surface behaviour was studied. The crust leather was coated with different types of pigment-acrylic binder (Very Soft, Soft and Medium Soft) finish formulations. The contact angle of both the acrylic films and the PABR finished leathers were measured against Water, Dimethyl sulfoxide (DMSO) and Hexadecane (HD). According to the study’s results, the surface properties of finished leather were directly related to the degree of wetting. The PABR was found to be effective at 1:3 for very soft binder, 1:2.5 for soft, 1:2 for medium soft binders due to higher contact angle and lower surface energy values (γsv). At 1:3 and 1:2.5, the contact angle of very soft and soft binder leather was 82.62° and 83.45° and for medium soft binder it was 82.67° at 1:2 ratio. The surface energy values of optimized PABR of very soft binder (1:3) was 28.29 (mN/M), soft binder (1:2.5) was 27.50 (mN/m) and medium soft binder (1:2) was 29.27 (mN/m). The optimized PABR work of adhesion values of very soft binder, soft binder and medium soft binder was 82.15 (mJm-2), 81.11 (mJm-2), 82.09 (mJm-2). In order to correlate the observed surface properties with leather finish properties, finished leathers were tested for finish adhesion, vamp flexing value, water vapour permeability, wet and dry rub fastness. According to the water vapour permeability, soft and medium binder showed good permeation due to the uncovering of nanopores. But the adhesion, grain crack resistance and grain smoothness were higher in the case of the soft binder. Overall leather properties divulges that the pigment to binder ratio and the type of binder plays an important role in surface properties of the finished leather. This study enables us to determine the optimal PABR for effective finish properties to meet the required leather standards for various usage, as well as better utilisation of finishing chemicals.

Multi-omics analysis of pigmentation related to proanthocyanidin biosynthesis in brown cotton (Gossypium hirsutum L.).

Naturally-colored brown cotton (NBC) fiber is an environmentally friendly raw source of fiber for textile applications. The fiber of some NBC cultivars exhibits flame-retardant properties, which can be used in textiles that require flame resistance. Proanthocyanidins or their derivatives are responsible for the brown pigment in NBC; however, how flame retardancy is related to pigmentation in NBC is poorly understood. To gain insight into brown pigment biosynthesis, we conducted comparative transcripts and metabolites profiling analysis of developing cotton fibers between the brown (MC-BL) and white (MC-WL) cotton near-isogenic lines (NILs), genetically different only in the Lc1 locus. In this study, mass spectrometry was used to detect metabolites in BL and WL developing fibers at 8, 12, 16, 20, 24, 36, and 40 days post anthesis (DPA) and mature fibers. Transcripts analysis was performed at two critical fiber developmental points, 8 DPA (fiber elongation) and 20 DPA (secondary cell wall deposition). We found 5836 (ESI MS positive mode) and 4541 (ESI MS negative mode) metabolites significantly different accumulated between BL and WL. Among them, 142 were known non-redundant metabolites, including organic acids, amino acids, and derivatives of the phenylpropanoid pathway. Transcript analysis determined 1691 (8 DPA) and 5073 (20 DPA) differentially expressed genes (DEGs) between BL and WL, with the majority of DEGs down-regulated at 20 DPA. Organic acids of the citric acid cycle were induced, while most of the detected amino acids were reduced in the MC-BL line. Both cis- and trans-stereoisomers of flavan-3-ols were detected in developing MC-WL and MC-BL fibers; however, the gallocatechin and catechin accumulated multiple times higher. Gas chromatography-mass spectrometry (GC-MS) analysis of fatty acids determined that palmitic acid long-chain alcohols were the main constituents of waxes of mature fibers. Energy-dispersive X-ray spectrometry (EDS) analysis of mature fibers revealed that potassium accumulated three times greater in MC-BL than in MC-WL mature fibers. This study provides novel insights into the biosynthesis of pigments and its association with flame retardancy in NBC fibers.