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Malík M, Mika OJ, Navrátilová Z, Killi UK, Tlustoš P, Patočka J. Health and Environmental Hazards of the Toxic Pteridium aquilinum (L.) Kuhn (Bracken Fern). Plants (Basel) 2023; 13:18. [PMID: 38202326 PMCID: PMC10780724 DOI: 10.3390/plants13010018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/13/2023] [Accepted: 12/18/2023] [Indexed: 01/12/2024]
Abstract
Bracken fern (Pteridium aquilinum (L.) Kuhn) is ubiquitous and acts as a cosmopolitan weed in pastures and similar environments. Despite its historical uses, it presents risks due to toxicity. This study, conducted in the second half of 2023, aimed to assess the environmental and health hazards of P. aquilinum, primarily focusing on its carcinogenic compound, ptaquiloside. The literature was comprehensively reviewed using diverse databases, including PubMed, Web of Science, Scopus, and Google Scholar. Information was synthesized from original research articles, meta-analyses, systematic reviews, and relevant animal studies. Animals grazing on bracken fern face annual production losses due to toxin exposure. The substantial impact on biodiversity, animal health, and human well-being arises from the presence of ptaquiloside and related compounds in milk, meat, and water, along with the increasing global prevalence of P. aquilinum and its swift colonization in acidic soil and fire-damaged areas. The objectives were to identify major bioactive compounds and explore their effects at molecular, cellular, pathological, and population levels. Various cooking techniques were considered to mitigate toxin exposure, although complete elimination remains unattainable. Therefore, the findings emphasize the need for cautious consumption. In conclusion, continued research is necessary to better understand and manage its environmental and health implications.
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Affiliation(s)
- Matěj Malík
- Department of Agroenvironmental Chemistry and Plant Nutrition, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha 6-Suchdol, Czech Republic; (M.M.); (P.T.)
| | - Otakar Jiří Mika
- Department of Crisis Management, Faculty of Security Management, Police Academy of the Czech Republic, Lhotecká 559/7, 143 01 Praha 4, Czech Republic
- Department of Radiology, Toxicology and Civil Protection, Faculty of Health and Social Studies, University of South Bohemia, J. Boreckého 1167/27, 370 11 České Budějovice, Czech Republic; (U.K.K.); (J.P.)
| | - Zdeňka Navrátilová
- Department of Botany, Faculty of Science, Charles University, Benátská 433/2, 128 00 Praha 2, Czech Republic;
| | - Uday Kumar Killi
- Department of Radiology, Toxicology and Civil Protection, Faculty of Health and Social Studies, University of South Bohemia, J. Boreckého 1167/27, 370 11 České Budějovice, Czech Republic; (U.K.K.); (J.P.)
| | - Pavel Tlustoš
- Department of Agroenvironmental Chemistry and Plant Nutrition, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha 6-Suchdol, Czech Republic; (M.M.); (P.T.)
| | - Jiří Patočka
- Department of Radiology, Toxicology and Civil Protection, Faculty of Health and Social Studies, University of South Bohemia, J. Boreckého 1167/27, 370 11 České Budějovice, Czech Republic; (U.K.K.); (J.P.)
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Hradecká 1285, 500 03 Hradec Králové, Czech Republic
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Park H, Cho Y, Lee J, Lee KM, Kim HJ, Lee J, Bahn YS, Son J. Evaluation and Monitoring of the Natural Toxin Ptaquiloside in Bracken Fern, Meat, and Dairy Products. Toxins (Basel) 2023; 15:toxins15030231. [PMID: 36977122 PMCID: PMC10053987 DOI: 10.3390/toxins15030231] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 02/28/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
Ptaquiloside, a naturally occurring cancer-causing substance in bracken fern, has been detected in the meat and milk of cows fed a diet containing bracken fern. A rapid and sensitive method for the quantitative analysis of ptaquiloside in bracken fern, meat, and dairy products was developed using the QuEChERS method and liquid chromatography-tandem mass spectrometry. The method was validated according to the Association of Official Analytical Chemists guidelines and met the criteria. A single matrix-matched calibration method with bracken fern has been proposed, which is a novel strategy that uses one calibration for multiple matrices. The calibration curve ranged from 0.1 to 50 µg/kg and showed good linearity (r2 > 0.99). The limits of detection and quantification were 0.03 and 0.09 µg/kg, respectively. The intraday and interday accuracies were 83.5-98.5%, and the precision was <9.0%. This method was used for the monitoring and exposure assessment of ptaquiloside in all routes of exposure. A total of 0.1 µg/kg of ptaquiloside was detected in free-range beef, and the daily dietary exposure of South Koreans to ptaquiloside was estimated at up to 3.0 × 10-5 µg/kg b.w./day. The significance of this study is to evaluate commercially available products in which ptaquiloside may be present, to monitor consumer safety.
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Affiliation(s)
- Hana Park
- Doping Control Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Yoeseph Cho
- Doping Control Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
- Department of Microbiology and Immunology, Institute for Immunology and Immunological Diseases, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Republic of Korea
| | - JiEun Lee
- KnA Consulting, Yongin-si 16942, Republic of Korea
| | - Kang Mi Lee
- Doping Control Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Ho Jun Kim
- Doping Control Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Jaeick Lee
- Doping Control Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Yong-Sun Bahn
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Junghyun Son
- Doping Control Center, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
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Kim MK, Kang JS, Kundu A, Kim HS, Lee BM. Risk Assessment and Risk Reduction of Ptaquiloside in Bracken Fern. Toxics 2023; 11:115. [PMID: 36850990 PMCID: PMC9959108 DOI: 10.3390/toxics11020115] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
This study was conducted to determine the optimal boiling time to reduce ptaquiloside (PTA) and to carry out a risk assessment for PTA, a representative toxic substance found in bracken fern (BF; Pteridium aquilinum), which is frequently consumed as food in East Asian countries. High-performance liquid chromatography showed that the concentration of PTA in BF was reduced by up to 99% after boiling for 20 min. Risk assessment results showed that the cancer margin of exposure (MOE; ≥ 25,000 = safe) to PTA for an average daily exposure scenario after boiling BF for 20 min was considered safe. In addition, the non-cancer MOE (≥ 300 = safe) to PTA under an average daily exposure scenario after BF boiling for 20 min was considered safe. However, human exposure to PTA was considered unsafe under the non-boiled BF exposure and maximum daily exposure scenarios. Therefore, boiling BF for at least 20 min is recommended before consumption, to reduce exposure to PTA as much as possible.
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Affiliation(s)
- Min Kook Kim
- Division of Toxicology, College of Pharmacy, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon-si 16419, Republic of Korea
| | - Ji Soo Kang
- Division of Toxicology, College of Pharmacy, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon-si 16419, Republic of Korea
| | - Amit Kundu
- Laboratory of Molecular Toxicology, College of Pharmacy, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon-si 16419, Republic of Korea
| | - Hyung Sik Kim
- Laboratory of Molecular Toxicology, College of Pharmacy, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon-si 16419, Republic of Korea
| | - Byung-Mu Lee
- Division of Toxicology, College of Pharmacy, Sungkyunkwan University, 2066 Seobu-ro, Jangan-gu, Suwon-si 16419, Republic of Korea
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Vetter J. The Norsesquiterpene Glycoside Ptaquiloside as a Poisonous, Carcinogenic Component of Certain Ferns. Molecules 2022; 27:molecules27196662. [PMID: 36235199 PMCID: PMC9570605 DOI: 10.3390/molecules27196662] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 11/05/2022]
Abstract
Previous studies related to the ptaquiloside molecule, a carcinogenic secondary metabolite known from the world of ferns, are summarised. Ptaquiloside (PTA) belongs to the group of norsesquiterpenes of the illudane type. The name illudane refers to the fungal taxa from which the first representatives of the molecular group were identified. Ptaquiloside occurs mainly in Pteridium fern species, although it is also known in other fern taxa. The species of the genus Pteridium are common, frequent invasive species on all continents, and PTA is formed in smaller or larger amounts in all organs of the affected species. The effects of PTA and of their derivatives on animals and humans are of great toxicological significance. Its basic chemical property is that the molecule can be transformed. First, with the loss of sugar moiety, ptaquilosine is formed, and then, under certain conditions, a dienone derivative (pteridienone) may arise. The latter can alkylate (through its cyclopropane groups) certain molecules, including DNA, in animal or human organisms. In this case, DNA adducts are formed, which can later have a carcinogenic effect through point mutations. The scope of the PTA is interdisciplinary in nature since, for example, molecules from plant biomass can enter the body of animals or humans in several ways (directly and indirectly). Due to its physico-chemical properties (excellent water solubility), PTA can get from the plant into the soil and then into different water layers. PTA molecules that enter the soil, but mainly water, undergo degradation (hydrolytic) processes, so it is very important to clarify the toxicological conditions of a given ecosystem and to estimate the possible risks caused by PTA. The toxicoses and diseases of the animal world (mainly for ruminant farm animals) caused by PTA are briefly described. The intake of PTA-containing plants as a feed source causes not only various syndromes but can also enter the milk (and meat) of animals. In connection with the toxicological safety of the food chain, it is important to investigate the transport of carcinogenic PTA metabolites between organisms in a reassuring manner and in detail. This is a global, interdisciplinary task. The present review aims to contribute to this.
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Affiliation(s)
- János Vetter
- Department of Botany, University of Veterinary Medicine, Pf. 2, 1400 Budapest, Hungary
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O'Driscoll C, Ramwell C, Harhen B, Morrison L, Clauson-Kaas F, Hansen HCB, Campbell G, Sheahan J, Misstear B, Xiao L. Ptaquiloside in Irish Bracken Ferns and Receiving Waters, with Implications for Land Managers. Molecules 2016; 21:E543. [PMID: 27128893 PMCID: PMC6273727 DOI: 10.3390/molecules21050543] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 04/14/2016] [Accepted: 04/19/2016] [Indexed: 11/20/2022] Open
Abstract
Ptaquiloside, along with other natural phytotoxins, is receiving increased attention from scientists and land use managers. There is an urgent need to increase empirical evidence to understand the scale of phytotoxin mobilisation and potential to enter into the environment. In this study the risk of ptaquiloside to drinking water was assessed by quantifying ptaquiloside in the receiving waters at three drinking water abstraction sites across Ireland and in bracken fronds surrounding the abstraction sites. We also investigated the impact of different management regimes (spraying, cutting and rolling) on ptaquiloside concentrations at plot-scale in six locations in Northern Ireland, UK. Ptaquiloside concentrations were determined using recent advances in the use of LC-MS for the detection and quantification of ptaquiloside. The results indicate that ptaquiloside is present in bracken stands surrounding drinking water abstractions in Ireland, and ptaquiloside concentrations were also observed in the receiving waters. Furthermore, spraying was found to be the most effective bracken management regime observed in terms of reducing ptaquiloside load. Increased awareness is vital on the implications of managing land with extensive bracken stands.
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Affiliation(s)
- Connie O'Driscoll
- Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, Dublin 2, Ireland.
- Department of Civil Engineering, National University of Ireland, Galway H91 HX31, Ireland.
| | - Carmel Ramwell
- Centre for Chemical Safety and Stewardship, Fera Science Ltd., Sand Hutton, York YO41 1LZ, UK.
| | - Brendan Harhen
- National Centre for Biomedical Engineering Science, National University of Ireland, Galway H91 HX31, Ireland.
| | - Liam Morrison
- Earth and Ocean Sciences, School of Natural Sciences and Ryan Institute, National University of Ireland, Galway H91 HX31, Ireland.
| | - Frederik Clauson-Kaas
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg DK-1871, Denmark.
| | - Hans Christian B Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg DK-1871, Denmark.
| | - Graeme Campbell
- College of Agriculture Food and Rural Enterprise Greenmount Campus, 45 Tirgracy Road, Muckamore, Antrim BT41 4PS, UK.
| | - Jerome Sheahan
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland, Galway H91 HX31, Ireland.
| | - Bruce Misstear
- Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, Dublin 2, Ireland.
| | - Liwen Xiao
- Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, Dublin 2, Ireland.
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Virgilio A, Sinisi A, Russo V, Gerardo S, Santoro A, Galeone A, Taglialatela-Scafati O, Roperto F. Ptaquiloside, the major carcinogen of bracken fern, in the pooled raw milk of healthy sheep and goats: an underestimated, global concern of food safety. J Agric Food Chem 2015; 63:4886-4892. [PMID: 25932502 DOI: 10.1021/acs.jafc.5b01937] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Bracken fern (Pteridium aquilinum) is a worldwide plant containing toxic substances, which represent an important chemical hazard for animals, including humans. Ptaquiloside, 1, a norsesquiterpenoid glucoside, is the major carcinogen of bracken detected in the food chain, particularly in the milk from farm animals. To date, ptaquiloside has been shown in the milk of cows feeding on a diet containing bracken fern. This is the first study that shows the systematic detection of ptaquiloside, 1, and reports its direct quantitation in pooled raw milk of healthy sheep and goats grazing on bracken. Ptaquiloside, 1, was detected by a sensitive method based on the chemical conversion of ptaquiloside, 1, into bromopterosine, 4, following gas chromatography-mass spectrometry (GC-MS) analysis. The presence of ptaquiloside, 1, possibly carcinogenic to humans, in the milk of healthy animals is an unknown potential health risk, thus representing a harmful and potential global concern of food safety.
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Affiliation(s)
- Antonella Virgilio
- †Department of Pharmacy, Naples University Federico II, Via D. Montesano 49, 80131 Naples, Italy
| | - Annamaria Sinisi
- †Department of Pharmacy, Naples University Federico II, Via D. Montesano 49, 80131 Naples, Italy
| | - Valeria Russo
- ‡Department of Veterinary Medicine and Animal Productions, Naples University Federico II, Via Delpino 1, 80137 Naples, Italy
| | - Salvatore Gerardo
- §Assessorato Politiche della Persona, Ufficio Veterinario, Igiene Alimenti, Tutela Sanitaria Consumatori, Regione Basilicata, Viale Verrastro 9, 85100 Potenza, Italy
| | - Adriano Santoro
- ‡Department of Veterinary Medicine and Animal Productions, Naples University Federico II, Via Delpino 1, 80137 Naples, Italy
| | - Aldo Galeone
- †Department of Pharmacy, Naples University Federico II, Via D. Montesano 49, 80131 Naples, Italy
| | | | - Franco Roperto
- #Department of Biology, Naples University Federico II, Via Cinzia 21, 80126 Naples, Italy
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Yurdakok B, Kismali G, Ozen D. Ptaquiloside-induced cytotoxicity in Crandall feline kidney and HGC-27 cells. Oncol Lett 2014; 8:1839-1843. [PMID: 25202422 PMCID: PMC4156249 DOI: 10.3892/ol.2014.2378] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 06/19/2014] [Indexed: 12/19/2022] Open
Abstract
Ptaquiloside (PTA) is a potent genotoxic carcinogenic compound, which is found in bracken ferns and predominantly causes gastric tumors in humans, as well as bladder tumors and chronic enzootic hematuria in cattle. The underlying molecular mechanisms of PTA remain a topic for interdisciplinary investigation. The aim of the present study was to determine the possible cytotoxic effect of 24 h of PTA exposure in Crandall feline kidney (CrFK) and human gastric cells (the HGC-27 cell line) using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and lactose dehydrogenase (LDH) analysis. The cytotoxic effects of PTA (0.0005–500 μg/ml) were found to increase in a dose-dependent manner, whereby the half maximal inhibitory concentration values were 11.17 and 11.86 μg/ml in the CrFK cells, and 2.03 and 2.56 μg/ml in the HGC-27 cells, by LDH and MTT assay, respectively. The results of the present study are consistent with those of previous studies associated with the cytotoxicity of PTA; however, cytotoxicity was identified to occur at significantly lower doses. This cytotoxic effect in vitro at particularly high doses may be linked to the initiation of carcinogenesis as a result of oxidative stress.
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Affiliation(s)
- Begum Yurdakok
- Department of Pharmacology and Toxicology, Ankara University Faculty of Veterinary Medicine, Ankara 06110, Turkey
| | - Gorkem Kismali
- Department of Biochemistry, Ankara University Faculty of Veterinary Medicine, Ankara 06110, Turkey
| | - Dogukan Ozen
- Department of Biostatistics, Ankara University Faculty of Veterinary Medicine, Ankara 06110, Turkey
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Gil da Costa RM, Oliveira PA, Bastos MMSM, Lopes CC, Lopes C. Ptaquiloside-induced early-stage urothelial lesions show increased cell proliferation and intact β-catenin and E-cadherin expression. Environ Toxicol 2014; 29:763-769. [PMID: 22859263 DOI: 10.1002/tox.21803] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 07/05/2012] [Accepted: 07/15/2012] [Indexed: 06/01/2023]
Abstract
Bracken (Pteridium aquilinum) is a carcinogenic plant whose main toxin, ptaquiloside, causes cancer in farm and laboratory animals. Ptaquiloside contaminates underground waters as well as meat and milk from bracken-grazing animals and is a suspected human carcinogen. A better understanding of the underlying mechanisms of carcinogenesis can be achieved by studying the early stages of this process. Unfortunately, most research on ptaquiloside has focused on the late, malignant, lesions, so the early changes of ptaquiloside-induced carcinogenesis remain largely unknown. This study aims to characterize early-stage ptaquiloside-induced urinary bladder lesions both morphologically and immunohistochemically. 12 male CD-1 mice were administered 0.5 mg ptaquiloside intraperitoneally, weekly, for 15 weeks, followed by 15 weeks without treatment. 12 control animals were administered saline. Bladders were tested immunohistochemically for antibodies against a cell proliferation marker (Ki-67), and two cell adhesion markers (E-cadherin and β-catenin). Two exposed animals died during the work. Six ptaquiloside-exposed mice developed low-grade and two developed high grade urothelial dysplasia. No lesions were detected on control animals. Significantly, increased (p < 0.05) Ki-67 labeling indices were found on dysplastic urothelium from ptaquiloside-exposed mice, compared with controls. No differences were found concerning E-cadherin and β-catenin expression. Early-stage ptaquiloside-induced urothelial lesions show increased cell proliferation but there is no evidence for reduced intercellular adhesiveness, though this may be a later event in tumor progression.
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Affiliation(s)
- Rui M Gil da Costa
- Pathology and Molecular Immunology Department, Abel Salazar Institute for Biomedical Sciences (ICBAS), University of Porto, Largo Prof. Abel Salazar 2, 4099-003-Porto, Portugal; Chemical Engineering Department, Engineering Faculty, LEPAE, University of Porto, Rua Dr. Roberto Frias s/n, 4200-465-Porto, Portugal
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Attya M, Nardi M, Tagarelli A, Sindona G. A new facile synthesis of d₄-pterosin B and d₄-bromopterosin, deuterated analogues of ptaquiloside. Molecules 2012; 17:5795-802. [PMID: 22592085 PMCID: PMC6268148 DOI: 10.3390/molecules17055795] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 05/09/2012] [Accepted: 05/14/2012] [Indexed: 12/04/2022] Open
Abstract
Ptaquiloside (Pta) is a potent carcinogen present in bracken fern and in soil matrices, that can potentially leach to the aquatic environment. More recently its presence in the milk of different farm animals has been reported. Pterosin B (Ptb) and bromopterosin (BrPt) represent the most convenient analogues in the detection of ptaquiloside by mass spectrometry. Pterosin sesquiterpenes are also involved in many patented biomedical protocols. In this work we introduce a new and convenient approach to the synthesis in three steps and more than 80% yield of d₄-pterosin B (d₄-Ptb) and d₄-bromopterosin (d₄-BrPt), useful as internal standards in the quantification of ptaquiloside.
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Affiliation(s)
- Mohamed Attya
- Department of Chemistry, University of Calabria, 87036 Arcavacata di Rende, Cosenza, Italy.
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