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B T SK, Hebbar UH, Annapurna Singh S. Isolation, purification, and physio-chemical characterization of melanin pigment from nigerseed hulls ( Guizotia abyssinica). Prep Biochem Biotechnol 2024:1-9. [PMID: 38995969 DOI: 10.1080/10826068.2024.2376579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2024]
Abstract
Plant melanin, a natural pigment, has gained significant attention recently due to its potential therapeutic and industrial applications. In this study, melanin pigments were extracted from Nigerseed hulls (NH) via alkali and acid extraction methods, followed by acid hydrolysis, organic solvent treatment, and repeated precipitation. The solubility of NH melanin was assessed, revealing solubility in alkali and dimethyl sulfoxide (DMSO) but insolubility in other common organic solvents. High-performance liquid chromatography (HPLC) was employed to measure the purity of NH melanin in comparison to standard melanin, while elemental analysis indicated a similarity between melanin extracted from nigerseed hulls and the standard counterpart. LC-MS data revealed a molecular weight of NH melanin. Furthermore, the stability of melanin was evaluated under varying conditions including temperature, oxidants, reducing agents, light exposure, and metal ion presence. Results demonstrated significant effects of Mg2+, Cu2+, and Fe2+ metal ions on melanin stability, with a minor effect observed for Ca2+, while sodium hyposulfite was found to destabilize the pigments. Our findings suggest that nigerseed hulls hold promise as a novel source for efficient melanin production, with potential applications in the food sector, food packaging, and biomedical fields.
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Affiliation(s)
- Sunil Kumar B T
- Department of Traditional Foods and Applied Nutrition, CSIR-Central Food Technological Research Institute, Mysuru, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Umesh H Hebbar
- Department of Food Engineering, CSIR-Central Food Technological Research Institute, Mysuru, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
| | - Sridevi Annapurna Singh
- Department of Traditional Foods and Applied Nutrition, CSIR-Central Food Technological Research Institute, Mysuru, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India
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2
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Hasse S, Sommer MC, Guenther S, Schulze C, Bekeschus S, von Woedtke T. Exploring the Influence of Cold Plasma on Epidermal Melanogenesis In Situ and In Vitro. Int J Mol Sci 2024; 25:5186. [PMID: 38791225 PMCID: PMC11120903 DOI: 10.3390/ijms25105186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 04/30/2024] [Accepted: 05/05/2024] [Indexed: 05/26/2024] Open
Abstract
Epidermal melanin synthesis determines an individual's skin color. In humans, melanin is formed by melanocytes within the epidermis. The process of melanin synthesis strongly depends on a range of cellular factors, including the fine-tuned interplay with reactive oxygen species (ROS). In this context, a role of cold atmospheric plasma (CAP) on melanin synthesis was proposed due to its tunable ROS generation. Herein, the argon-driven plasma jet kINPen® MED was employed, and its impact on melanin synthesis was evaluated by comparison with known stimulants such as the phosphodiesterase inhibitor IBMX and UV radiation. Different available model systems were employed, and the melanin content of both cultured human melanocytes (in vitro) and full-thickness human skin biopsies (in situ) were analyzed. A histochemical method detected melanin in skin tissue. Cellular melanin was measured by NIR autofluorescence using flow cytometry, and a highly sensitive HPLC-MS method was applied, which enabled the differentiation of eu- and pheomelanin by their degradation products. The melanin content in full-thickness human skin biopsies increased after repeated CAP exposure, while there were only minor effects in cultured melanocytes compared to UV radiation and IBMX treatment. Based on these findings, CAP does not appear to be a useful option for treating skin pigmentation disorders. On the other hand, the risk of hyperpigmentation as an adverse effect of CAP application for wound healing or other dermatological diseases seems to be neglectable.
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Affiliation(s)
- Sybille Hasse
- Leibniz Institute for Plasma Science and Technology e.V. (INP), a Member of the Leibniz Health Technologies Research Alliance, Felix-Hausdorff-Str. 2, 17489 Greifswald, Germany; (M.-C.S.); (S.B.); (T.v.W.)
| | - Marie-Christine Sommer
- Leibniz Institute for Plasma Science and Technology e.V. (INP), a Member of the Leibniz Health Technologies Research Alliance, Felix-Hausdorff-Str. 2, 17489 Greifswald, Germany; (M.-C.S.); (S.B.); (T.v.W.)
| | - Sebastian Guenther
- Institute of Pharmacy, Department Pharmaceutical Biology, Greifswald University, Friedrich-Ludwig-Jahn-Str. 17, 17489 Greifswald, Germany; (S.G.); (C.S.)
| | - Christian Schulze
- Institute of Pharmacy, Department Pharmaceutical Biology, Greifswald University, Friedrich-Ludwig-Jahn-Str. 17, 17489 Greifswald, Germany; (S.G.); (C.S.)
| | - Sander Bekeschus
- Leibniz Institute for Plasma Science and Technology e.V. (INP), a Member of the Leibniz Health Technologies Research Alliance, Felix-Hausdorff-Str. 2, 17489 Greifswald, Germany; (M.-C.S.); (S.B.); (T.v.W.)
| | - Thomas von Woedtke
- Leibniz Institute for Plasma Science and Technology e.V. (INP), a Member of the Leibniz Health Technologies Research Alliance, Felix-Hausdorff-Str. 2, 17489 Greifswald, Germany; (M.-C.S.); (S.B.); (T.v.W.)
- Institute for Hygiene and Environmental Medicine, Greifswald University Medical Centre, Walther-Rathenau-Str. 48, 17489 Greifswald, Germany
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Sarkar H, Tracey-White D, Hagag AM, Burgoyne T, Nair N, Jensen LD, Edwards MM, Moosajee M. Loss of REP1 impacts choroidal melanogenesis and vasculogenesis in choroideremia. Biochim Biophys Acta Mol Basis Dis 2024; 1870:166963. [PMID: 37989423 PMCID: PMC11157692 DOI: 10.1016/j.bbadis.2023.166963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 10/13/2023] [Accepted: 11/14/2023] [Indexed: 11/23/2023]
Abstract
Choroideremia (CHM) is a rare X-linked chorioretinal dystrophy affecting the photoreceptors, retinal pigment epithelium (RPE) and choroid, however, the involvement of the choroid in disease progression is not fully understood. CHM is caused by mutations in the CHM gene, encoding the ubiquitously expressed Rab escort protein 1 (REP1). REP1 plays an important role in intracellular trafficking of vesicles, including melanosomes. In this study, we examined the ultrastructure of the choroid in chmru848 fish and Chmnull/WT mouse models using transmission electron and confocal microscopy. Significant pigmentary disruptions were observed, with lack of melanosomes in the choroid of chmru848 fish from 4 days post fertilisation (4dpf), and a reduction in choroidal blood vessel diameter and interstitial pillars suggesting a defect in vasculogenesis. Total melanin and expression of melanogenesis genes tyr, tryp1a, mitf, dct and pmel were also reduced from 4dpf. In Chmnull/WT mice, choroidal melanosomes were significantly smaller at 1 month, with reduced eumelanin at 1 year. The choroid in CHM patients were also examined using spectral domain optical coherence tomography (SD-OCT) and OCT-angiography (OCT-A) and the area of preserved choriocapillaris (CC) was found to be smaller than that of overlying photoreceptors, suggesting that the choroid is degenerating at a faster rate. Histopathology of an enucleated eye from a 74-year-old CHM male patient revealed isolated areas of RPE but no associated underlying CC. Pigmentary disruptions in CHM animal models reveal an important role for REP1 in melanogenesis, and drugs that improve melanin production represent a potential novel therapeutic avenue.
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Affiliation(s)
- Hajrah Sarkar
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK; The Francis Crick Institute, London, UK
| | - Dhani Tracey-White
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
| | - Ahmed M Hagag
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK; Department of Genetics, Moorfields Eye Hospital NHS Foundation Trust, London, UK; Boehringer Ingelheim Limited, Bracknell, UK
| | - Thomas Burgoyne
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK
| | - Neelima Nair
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK; The Francis Crick Institute, London, UK
| | - Lasse D Jensen
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
| | - Malia M Edwards
- The Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Mariya Moosajee
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London, UK; Department of Genetics, Moorfields Eye Hospital NHS Foundation Trust, London, UK; The Francis Crick Institute, London, UK.
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4
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Song W, Yang H, Liu S, Yu H, Li D, Li P, Xing R. Melanin: insights into structure, analysis, and biological activities for future development. J Mater Chem B 2023; 11:7528-7543. [PMID: 37432655 DOI: 10.1039/d3tb01132a] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
Melanin, a widely distributed pigment found in various organisms, possesses distinct structures that can be classified into five main types: eumelanin (found in animals and plants), pheomelanin (found in animals and plants), allomelanin (found in plants), neuromelanin (found in animals), and pyomelanin (found in fungi and bacteria). In this review, we present an overview of the structure and composition of melanin, as well as the various spectroscopic identification methods that can be used, such as Fourier transform infrared (FTIR) spectroscopy, electron spin resonance (ESR) spectroscopy, and thermogravimetric analysis (TGA). We also provide a summary of the extraction methods of melanin and its diverse biological activities, including antibacterial properties, anti-radiation effects, and photothermal effects. The current state of research on natural melanin and its potential for further development is discussed. In particular, the review provides a comprehensive summary of the analysis methods used to determine melanin species, offering valuable insights and references for future research. Overall, this review aims to provide a thorough understanding of the concept and classification of melanin, its structure, physicochemical properties, and structural identification methods, as well as its various applications in the field of biology.
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Affiliation(s)
- Wen Song
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
- University of Chinese Academy of Sciences, Beijing 100000, China
- Department of Food Science & Technology, Faculty of Science, National University of Singapore, 117546, Singapore.
| | - Haoyue Yang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
| | - Song Liu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 7 Nanhai Road, Qingdao 266000, China
| | - Huahua Yu
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 7 Nanhai Road, Qingdao 266000, China
| | - Dan Li
- Department of Food Science & Technology, Faculty of Science, National University of Singapore, 117546, Singapore.
| | - Pengcheng Li
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 7 Nanhai Road, Qingdao 266000, China
| | - Ronge Xing
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), No. 7 Nanhai Road, Qingdao 266000, China
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Wakamatsu K, Ito S. Recent Advances in Characterization of Melanin Pigments in Biological Samples. Int J Mol Sci 2023; 24:ijms24098305. [PMID: 37176019 PMCID: PMC10179066 DOI: 10.3390/ijms24098305] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 04/23/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
The melanin pigments eumelanin (EM) and pheomelanin (PM), which are dark brown to black and yellow to reddish-brown, respectively, are widely found among vertebrates. They are produced in melanocytes in the epidermis, hair follicles, the choroid, the iris, the inner ear, and other tissues. The diversity of colors in animals is mainly caused by the quantity and quality of their melanin, such as by the ratios of EM versus PM. We have developed micro-analytical methods to simultaneously measure EM and PM and used these to study the biochemical and genetic fundamentals of pigmentation. The photoreactivity of melanin has become a major focus of research because of the postulated relevance of EM and PM for the risk of UVA-induced melanoma. Our biochemical methods have found application in many clinical studies on genetic conditions associated with alterations in pigmentation. Recently, besides chemical degradative methods, other methods have been developed for the characterization of melanin, and these are also discussed here.
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Affiliation(s)
- Kazumasa Wakamatsu
- Institute for Melanin Chemistry, Fujita Health University, Toyoake 470-192, Aichi, Japan
| | - Shosuke Ito
- Institute for Melanin Chemistry, Fujita Health University, Toyoake 470-192, Aichi, Japan
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Terranova ML. Prominent Roles and Conflicted Attitudes of Eumelanin in the Living World. Int J Mol Sci 2023; 24:ijms24097783. [PMID: 37175490 PMCID: PMC10178024 DOI: 10.3390/ijms24097783] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/17/2023] [Accepted: 04/22/2023] [Indexed: 05/15/2023] Open
Abstract
Eumelanin, a macromolecule widespread in all the living world and long appreciated for its protective action against harmful UV radiation, is considered the beneficial component of the melanin family (ευ means good in ancient Greek). This initially limited picture has been rather recently extended and now includes a variety of key functions performed by eumelanin in order to support life also under extreme conditions. A lot of still unexplained aspects characterize this molecule that, in an evolutionary context, survived natural selection. This paper aims to emphasize the unique characteristics and the consequent unusual behaviors of a molecule that still holds the main chemical/physical features detected in fossils dating to the late Carboniferous. In this context, attention is drawn to the duality of roles played by eumelanin, which occasionally reverses its functional processes, switching from an anti-oxidant to a pro-oxidant behavior and implementing therefore harmful effects.
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Affiliation(s)
- Maria Letizia Terranova
- Dipartimento Scienze e Tecnologie Chimiche, Università degli Studi di Roma "Tor Vergata", Via della Ricerca Scientifica, 00133 Roma, Italy
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7
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Velazco PM, Almeida FC, Cláudio VC, Giménez AL, Giannini NP. A New Species of Histiotus Gervais, 1856 (Chiroptera, Vespertilionidae), from the Pacific Coast of Northern Peru. AMERICAN MUSEUM NOVITATES 2021. [DOI: 10.1206/3979.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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8
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Understanding the way eumelanin works: A unique example of properties and skills driven by molecular heterogeneity. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.123952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Ito S, Del Bino S, Hirobe T, Wakamatsu K. Improved HPLC Conditions to Determine Eumelanin and Pheomelanin Contents in Biological Samples Using an Ion Pair Reagent. Int J Mol Sci 2020; 21:ijms21145134. [PMID: 32698502 PMCID: PMC7404343 DOI: 10.3390/ijms21145134] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/08/2020] [Accepted: 07/16/2020] [Indexed: 12/22/2022] Open
Abstract
Alkaline hydrogen peroxide oxidation (AHPO) of eumelanin and pheomelanin, two major classes of melanin pigments, affords pyrrole-2,3,5-tricarboxylic acid (PTCA), pyrrole-2,3-dicarboxylic acid (PDCA) and pyrrole-2,3,4,5-tetracarboxylic acid (PTeCA) from eumelanin and thiazole-2,4,5-tricarboxylic acid (TTCA) and thiazole-4,5-dicarboxylic acid (TDCA) from pheomelanin. Quantification of these five markers by HPLC provides useful information on the quantity and structural diversity of melanins in various biological samples. HPLC analysis of these markers using the original method of 0.1 M potassium phosphate buffer (pH 2.1):methanol = 99:1 (85:15 for PTeCA) on a reversed-phase column had some problems, including the short lifetime of the column and, except for the major eumelanin marker PTCA, other markers were occasionally overlapped by interfering peaks in samples containing only trace levels of these markers. These problems can be overcome by the addition of an ion pair reagent for anions, such as tetra-n-butylammonium bromide (1 mM), to retard the elution of di-, tri- and tetra-carboxylic acids. The methanol concentration was increased to 17% (30% for PTeCA) and the linearity, reproducibility, and recovery of the markers with this improved method is good to excellent. This improved HPLC method was compared to the original method using synthetic melanins, mouse hair, human hair, and human epidermal samples. In addition to PTCA, TTCA, a major marker for pheomelanin, showed excellent correlations between both HPLC methods. The other markers showed an attenuation of the interfering peaks with the improved method. We recommend this improved HPLC method for the quantitative analysis of melanin markers following AHPO because of its simplicity, accuracy, and reproducibility.
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Affiliation(s)
- Shosuke Ito
- Department of Chemistry, Fujita Health University School of Medical Sciences, Toyoake 470-1192, Japan
- Correspondence: (S.I.); (K.W.); Tel.: +81-562-93-9849 (S.I. & K.W.); Fax: +81-562-93-4595 (S.I. & K.W.)
| | - Sandra Del Bino
- L’Oreal Research and Innovation, 93600 Aulnay-sous-Bois, France;
| | - Tomohisa Hirobe
- Shinjuku Skin Clinic, 10F Shinjuku M-SQUARE, 3-24-1 Shinjuku, Shinjuku-ku, Tokyo 160-0022, Japan;
| | - Kazumasa Wakamatsu
- Department of Chemistry, Fujita Health University School of Medical Sciences, Toyoake 470-1192, Japan
- Correspondence: (S.I.); (K.W.); Tel.: +81-562-93-9849 (S.I. & K.W.); Fax: +81-562-93-4595 (S.I. & K.W.)
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Affenzeller S, Wolkenstein K, Frauendorf H, Jackson DJ. Challenging the concept that eumelanin is the polymorphic brown banded pigment in Cepaea nemoralis. Sci Rep 2020; 10:2442. [PMID: 32051478 PMCID: PMC7016172 DOI: 10.1038/s41598-020-59185-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 01/21/2020] [Indexed: 12/15/2022] Open
Abstract
The common grove snail Cepaea nemoralis displays a stable pigmentation polymorphism in its shell that has held the attention of scientists for decades. While the details of the molecular mechanisms that generate and maintain this diversity remain elusive, it has long been employed as a model system to address questions related to ecology, population genetics and evolution. In order to contribute to the ongoing efforts to identify the genes that generate this polymorphism we have tested the long-standing assumption that melanin is the pigment that comprises the dark-brown bands. Surprisingly, using a newly established analytical chemical method, we find no evidence that eumelanin is differentially distributed within the shells of C. nemoralis. Furthermore, genes known to be responsible for melanin deposition in other metazoans are not differentially expressed within the shell-forming mantle tissue of C. nemoralis. These results have implications for the continuing search for the supergene that generates the various pigmentation morphotypes.
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Affiliation(s)
- Susanne Affenzeller
- Department of Geobiology, Georg-August University of Göttingen, Goldschmidtstrasse 3, 37077, Göttingen, Germany
| | - Klaus Wolkenstein
- Department of Geobiology, Georg-August University of Göttingen, Goldschmidtstrasse 3, 37077, Göttingen, Germany
| | - Holm Frauendorf
- Institute of Organic & Biomolecular Chemistry, Georg-August University of Göttingen, Tammannstrasse 2, 37077, Göttingen, Germany
| | - Daniel J Jackson
- Department of Geobiology, Georg-August University of Göttingen, Goldschmidtstrasse 3, 37077, Göttingen, Germany.
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Affenzeller S, Wolkenstein K, Frauendorf H, Jackson DJ. Eumelanin and pheomelanin pigmentation in mollusc shells may be less common than expected: insights from mass spectrometry. Front Zool 2019; 16:47. [PMID: 31889966 PMCID: PMC6929474 DOI: 10.1186/s12983-019-0346-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 12/13/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The geometric patterns that adorn the shells of many phylogenetically disparate molluscan species are comprised of pigments that span the visible spectrum. Although early chemical studies implicated melanin as a commonly employed pigment, surprisingly little evidence generated with more recent and sensitive techniques exists to support these observations. RESULTS Here we present the first mass spectrometric investigations for the presence of eumelanin and pheomelanin in 13 different molluscan species from three conchiferan classes: Bivalvia, Cephalopoda and Gastropoda. In the bivalve Mytilus edulis we demonstrate that eumelanin mainly occurs in the outermost, non-mineralised and highly pigmented layer of the shell (often referred to as the periostracum). We also identified eumelanin in the shells of the cephalopod Nautilus pompilius and the marine gastropods Clanculus pharaonius and Steromphala adriatica. In the terrestrial gastropod Cepaea nemoralis we verify the presence of pheomelanin in a mollusc shell for the first time. Surprisingly, in a large number of brown/black coloured shells we did not find any evidence for either type of melanin. CONCLUSIONS We recommend methods such as high-performance liquid chromatography with mass spectrometric detection for the analysis of complex biological samples to avoid potential false-positive identification of melanin. Our results imply that many molluscan species employ as yet unidentified pigments to pattern their shells. This has implications for our understanding of how molluscs evolved the ability to pigment and pattern their shells, and for the identification of the molecular mechanisms that regulate these processes.
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Affiliation(s)
- Susanne Affenzeller
- Department of Geobiology, Georg-August University of Göttingen, Goldschmidtstr. 3, 37077 Göttingen, Germany
| | - Klaus Wolkenstein
- Department of Geobiology, Georg-August University of Göttingen, Goldschmidtstr. 3, 37077 Göttingen, Germany
| | - Holm Frauendorf
- Institute of Organic & Biomolecular Chemistry, Georg-August University of Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Daniel J. Jackson
- Department of Geobiology, Georg-August University of Göttingen, Goldschmidtstr. 3, 37077 Göttingen, Germany
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