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Cheetham AG, Plunkett S, Campbell P, Hilldrup J, Coffa BG, Gilliland S, Eckard S. Analysis and differentiation of tobacco-derived and synthetic nicotine products: Addressing an urgent regulatory issue. PLoS One 2022; 17:e0267049. [PMID: 35421170 PMCID: PMC9009602 DOI: 10.1371/journal.pone.0267049] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 03/22/2022] [Indexed: 11/18/2022] Open
Abstract
There is significant regulatory and economic need to distinguish analytically between tobacco-derived nicotine (TDN) and synthetic nicotine (SyN) in commercial products. Currently, commercial e-liquid and oral pouch products are available that contain tobacco-free nicotine, which could be either extracted from tobacco or synthesized. While tobacco products that contain TDN are regulated by FDA Center for Tobacco Products, those with SyN are currently not in the domain of any regulatory authority. This regulatory difference provides an economic incentive to use or claim the use of SyN to remain on the market without submitting a Premarket Tobacco Product Application. TDN is ~99.3% (S)-nicotine, whereas SyN can vary from racemic (50/50 (R)/(S)) to ≥ 99% (S)-nicotine, i.e., chemically identical to the tobacco-derived compound. Here we report efforts to distinguish between TDN and SyN in various samples by characterizing impurities, (R)/(S)-nicotine enantiomer ratio, (R)/(S)-nornicotine enantiomer ratio, and carbon-14 (14C) content. Only 14C analysis accurately and precisely differentiated TDN (100% 14C) from SyN (35-38% 14C) in all samples tested. 14C quantitation of nicotine samples by accelerator mass spectrometry is a reliable determinate of nicotine source and can be used to identify misbranded product labelled as containing SyN. This is the first report to distinguish natural, bio-based nicotine from synthetic, petroleum-based nicotine across a range of pure nicotine samples and commercial e-liquid products.
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Affiliation(s)
| | - Susan Plunkett
- Enthalpy Analytical, LLC, Richmond, Virginia, United States of America
- Consilium Sciences, LLC, Richmond, Virginia, United States of America
| | - Preston Campbell
- Consilium Sciences, LLC, Richmond, Virginia, United States of America
| | - Jacob Hilldrup
- Enthalpy Analytical, LLC, Richmond, Virginia, United States of America
| | - Bonnie G. Coffa
- Enthalpy Analytical, LLC, Richmond, Virginia, United States of America
| | - Stan Gilliland
- Consilium Sciences, LLC, Richmond, Virginia, United States of America
| | - Steve Eckard
- Enthalpy Analytical, LLC, Richmond, Virginia, United States of America
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Cai K, Zhao H, Yin R, Lin Y, Lei B, Wang A, Pan W, Cai B, Gao W, Wang F. Chiral determination of nornicotine, anatabine and anabasine in tobacco by achiral gas chromatography with (1S)-(-)-camphanic chloride derivatization: Application to enantiomeric profiling of cultivars and curing processes. J Chromatogr A 2020; 1626:461361. [PMID: 32797840 DOI: 10.1016/j.chroma.2020.461361] [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: 03/25/2020] [Revised: 06/01/2020] [Accepted: 06/19/2020] [Indexed: 10/24/2022]
Abstract
The alkaloid enantiomers are well-known to have different physiological and pharmacological effects, and to play an important role in enantioselectivity metabolism with enzymes catalysis in tobacco plants. Here, we developed an improved method for simultaneous and high-precision determination of the individual enantiomers of nornicotine, anatabine and anabasine in four tobacco matrices, based on an achiral gas chromatography-nitrogen phosphorus detector (GCNPD) with commonly available Rtx-200 column using (1S)-(-)-camphanic chloride derivatization. The method development consists of the optimization of extraction and derivatization, screening of achiral column, analysis of the fragmentation mechanisms and evaluation of matrix effect (ME). Under the optimized experimental conditions, the current method exhibited excellent detection capability for the alkaloid enantiomers, with coefficients of determination (R2) > 0.9989 and normality test of residuals P > 0.05 in linear regression parameters. The ME can be neglected for the camphanic derivatives. The limit of detection (LOD) and limit of quantitation (LOQ) ranged from 0.087 to 0.24 μg g - 1 and 0.29 to 0.81 μg g - 1, respectively. The recoveries and within-laboratory relative standard deviations (RSDR) were 94.3%~104.2% and 0.51%~3.89%, respectively. The developed method was successfully applied to determine the enantiomeric profiling of cultivars and curing processes. Tobacco cultivars had a significant impact on the nornicotine, anatabine, anabasine concentration and enantiomeric fraction (EF) of (R)-nornicotine, whereas the only significant change induced by the curing processes was an increase in the EF of (R)-anabasine.
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Affiliation(s)
- Kai Cai
- Guizhou Academy of Tobacco Science, Guiyang 550081, China; College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Huina Zhao
- Guizhou Academy of Tobacco Science, Guiyang 550081, China
| | - Runsheng Yin
- State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 55081, China
| | - Yechun Lin
- Guizhou Academy of Tobacco Science, Guiyang 550081, China
| | - Bo Lei
- Guizhou Academy of Tobacco Science, Guiyang 550081, China
| | - Anping Wang
- Key Laboratory for Information System of Mountainous Area and Protection of Ecological, Environment of Guizhou Province, Guizhou Normal University, Guiyang, Guizhou 550025, China
| | - Wenjie Pan
- Guizhou Academy of Tobacco Science, Guiyang 550081, China
| | - Bin Cai
- Haikou Cigar Research Institute, Hainan Provincial Branch of China National Tobacco Corporation, Haikou 571100, China
| | - Weichang Gao
- Guizhou Academy of Tobacco Science, Guiyang 550081, China.
| | - Feng Wang
- Guizhou Academy of Tobacco Science, Guiyang 550081, China.
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Ji H, Wu Y, Fannin F, Bush L. Determination of tobacco alkaloid enantiomers using reversed phase UPLC/MS/MS. Heliyon 2019; 5:e01719. [PMID: 31193304 PMCID: PMC6525314 DOI: 10.1016/j.heliyon.2019.e01719] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 04/17/2019] [Accepted: 05/09/2019] [Indexed: 11/12/2022] Open
Abstract
Nʹ-Nitrosonornicotine (NNN), a carcinogenic tobacco-specific Nʹ-nitrosamine (TSNA), is on the FDA list of harmful and potentially harmful constituents (HPHCs). Nornicotine, a product of the demethylation of nicotine, is the immediate alkaloid precursor for NNN formation. Nicotine, nornicotine and NNN are optically active. The accumulation of the isomers of nicotine, nornicotine, and NNN impacts their biological activity. In this paper, we report the determination of tobacco alkaloid enantiomers (including nicotine, nornicotine, anabasine, and anatabine) in samples of different tobacco lines using a reversed phase ultra-performance liquid chromatography-tandem mass spectrometer (UPLC/MS/MS) method. Current method demonstates excellent detection capability for all alkaloid enantiomers, with correlation coefficients (r2) > 0.996 within their linear dynamic ranges. The limit of detection (LOD) and limit of quantitation (LOQ) of all analytes are less than 10 ng/mL and 30 ng/mL, respectively. In addition, their recovery and coefficient of variation (CV%) are within 100–115% and 0.2–3.7%, respectively. The method validated in this paper is simple, fast, and sensitive for the quantification of alkaloid enantiomers in tobacco leaf and has been applied to investigations of tobacco alkaloid enantiomer ratios in different tobacco lines and tobacco products.
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Affiliation(s)
- Huihua Ji
- Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY 40546, USA
| | - Ying Wu
- Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, KY 40546, USA
| | - Franklin Fannin
- Plant and Soil Science Department, University of Kentucky, Lexington, KY 40546, USA
| | - Lowell Bush
- Plant and Soil Science Department, University of Kentucky, Lexington, KY 40546, USA
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Pan D, Sun M, Wang Y, Lv P, Wu X, Li QX, Cao H, Hua R. Characterization of Nicotine Catabolism through a Novel Pyrrolidine Pathway in Pseudomonas sp. S-1. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:7393-7401. [PMID: 29932673 DOI: 10.1021/acs.jafc.8b01868] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nicotine is a major toxic alkaloid in wastes generated from tobacco production and cigarette manufacturing. In the present work, a nicotine-degrading bacterial strain was isolated from tobacco powdery waste. The isolate was identified as Pseudomonas sp. S-1 based on morphology, physiology, and 16S rRNA gene sequence. Suitable conditions of isolate S-1 for nicotine degradation were pH 7.0 and 30 °C. Catabolic intermediates of nicotine were isolated with preparative-HPLC and characterized with LC-HRMS and NMR. The catabolic pathways of nicotine were involved in dehydrogenation, oxidation, hydrolysis, and hydroxylation. Interestingly, nicotine catabolism in strain S-1 undergoes a new pyrrolidine pathway that differs from the other three catabolic pathways in bacterial species. This work sheds light on catabolic diversity of nicotine and heteroaromatics.
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Affiliation(s)
- Dandan Pan
- College of Resources and Environment , Anhui Agricultural University , Key Laboratory of Agri-Food Safety of Anhui Province , Hefei 230036 , China
| | - Mengmeng Sun
- College of Resources and Environment , Anhui Agricultural University , Key Laboratory of Agri-Food Safety of Anhui Province , Hefei 230036 , China
| | - Yawen Wang
- College of Resources and Environment , Anhui Agricultural University , Key Laboratory of Agri-Food Safety of Anhui Province , Hefei 230036 , China
| | - Pei Lv
- College of Resources and Environment , Anhui Agricultural University , Key Laboratory of Agri-Food Safety of Anhui Province , Hefei 230036 , China
| | - Xiangwei Wu
- College of Resources and Environment , Anhui Agricultural University , Key Laboratory of Agri-Food Safety of Anhui Province , Hefei 230036 , China
| | - Qing X Li
- Department of Molecular Biosciences and Bioengineering , University of Hawaii at Manoa , 1955 East-West Road , Honolulu , Hawaii 96822 , United States
| | - Haiqun Cao
- College of Resources and Environment , Anhui Agricultural University , Key Laboratory of Agri-Food Safety of Anhui Province , Hefei 230036 , China
| | - Rimao Hua
- College of Resources and Environment , Anhui Agricultural University , Key Laboratory of Agri-Food Safety of Anhui Province , Hefei 230036 , China
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Conversion of nornicotine to 6-hydroxy-nornicotine and 6-hydroxy-myosmine by Shinella sp. strain HZN7. Appl Microbiol Biotechnol 2016; 100:10019-10029. [PMID: 27568381 DOI: 10.1007/s00253-016-7805-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/05/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022]
Abstract
Nornicotine is a natural alkaloid produced by plants in the genus Nicotiana and is structurally related to nicotine. Importantly, nornicotine is the direct precursor of tobacco-specific nitrosamine N'-nitrosonornicotine, which is a highly potent human carcinogen. Microbial detoxification and degradation of nicotine have been well characterized; however, until now, there has been no information on the molecular mechanism of nornicotine degradation. In this study, we demonstrate the transformation of nornicotine by the nicotine-degrading strain Shinella sp. HZN7. Three transformation products were identified as 6-hydroxy-nornicotine, 6-hydroxy-myosmine, and 6-hydroxy-pseudooxy-nornicotine by UV spectroscopy, high-resolution mass spectrometry, nuclear magnetic resonance, and Fourier transform-infrared spectroscopy analyses. The two-component nicotine dehydrogenase genes nctA1 and nctA2 were cloned, and their product, NctA, was confirmed to be responsible for the conversion of nornicotine into 6-hydroxy-nornicotine as well as nicotine into 6-hydroxy-nicotine. The 6-hydroxy-nicotine oxidase, NctB, catalyzed the oxidation of 6-hydroxy-nornicotine to 6-hydroxy-myosmine, and it spontaneously hydrolyzed into 6-hydroxy-pseudooxy-nornicotine. However, 6-hydroxy-pseudooxy-nornicotine could not be further degraded by strain HZN7. This study demonstrated that nornicotine is partially transformed by strain HZN7 via nicotine degradation pathway.
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Cai B, Jack AM, Lewis RS, Dewey RE, Bush LP. (R)-nicotine biosynthesis, metabolism and translocation in tobacco as determined by nicotine demethylase mutants. PHYTOCHEMISTRY 2013; 95:188-96. [PMID: 23849545 DOI: 10.1016/j.phytochem.2013.06.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 05/13/2013] [Accepted: 06/11/2013] [Indexed: 06/02/2023]
Abstract
Nicotine is a chiral compound and consequently exists as two enantiomers. Since (R)-nicotine consists of less than 0.5% of total nicotine pool in tobacco, few investigations relating to (R)-nicotine have been reported. However, previous studies of nicotine demethylases suggested there was substantial amount of (R)-nicotine at synthesis in the tobacco plant. In this study, the accumulation and translocation of (R)-nicotine in tobacco was analyzed. The accumulation of nicotine and its demethylation product the nornicotine enantiomers, were investigated in different tobacco plant parts and at different growth and post-harvest stages. Scion/rootstock grafts were used to separate the contributions of roots (source) from leaves (sink) to the final accumulation of nicotine and nornicotine in leaf tissue. The results indicate that 4% of nicotine is in the (R) form at synthesis in the root. After the majority of (R)-nicotine is selectively demethylated by CYP82E4, CYP82E5v2 and CYP82E10 in the root, nicotine and nornicotine are translocated to leaf, where more nicotine becomes demethylated. Depending on the CYP82E4 activity in senescing leaf, constant low (R)-nicotine remains in the tobacco leaf and variable nornicotine composition is produced. These results confirmed the enantioselectivity of three nicotine demethylases in planta, could be used to predict the changes of nicotine and nornicotine composition, and may facilitate demethylase discovery in the future.
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Affiliation(s)
- Bin Cai
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546-0312, United States
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Dewey RE, Xie J. Molecular genetics of alkaloid biosynthesis in Nicotiana tabacum. PHYTOCHEMISTRY 2013; 94:10-27. [PMID: 23953973 DOI: 10.1016/j.phytochem.2013.06.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 05/28/2013] [Accepted: 05/30/2013] [Indexed: 05/18/2023]
Abstract
Alkaloids represent an extensive group of nitrogen-containing secondary metabolites that are widely distributed throughout the plant kingdom. The pyridine alkaloids of tobacco (Nicotiana tabacum L.) have been the subject of particularly intensive investigation, driven largely due to the widespread use of tobacco products by society and the role that nicotine (16) (see Fig. 1) plays as the primary compound responsible for making the consumption of these products both pleasurable and addictive. In a typical commercial tobacco plant, nicotine (16) comprises about 90% of the total alkaloid pool, with the alkaloids nornicotine (17) (a demethylated derivative of nicotine), anatabine (15) and anabasine (5) making up most of the remainder. Advances in molecular biology have led to the characterization of the majority of the genes encoding the enzymes directly responsible the biosynthesis of nicotine (16) and nornicotine (17), while notable gaps remain within the anatabine (15) and anabasine (5) biosynthetic pathways. Several of the genes involved in the transcriptional regulation and transport of nicotine (16) have also been elucidated. Investigations of the molecular genetics of tobacco alkaloids have not only provided plant biologists with insights into the mechanisms underlying the synthesis and accumulation of this important class of plant alkaloids, they have also yielded tools and strategies for modifying the tobacco alkaloid composition in a manner that can result in changing the levels of nicotine (16) within the leaf, or reducing the levels of a potent carcinogenic tobacco-specific nitrosamine (TSNA). This review summarizes recent advances in our understanding of the molecular genetics of alkaloid biosynthesis in tobacco, and discusses the potential for applying information accrued from these studies toward efforts designed to help mitigate some of the negative health consequences associated with the use of tobacco products.
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Affiliation(s)
- Ralph E Dewey
- Department of Crop Science, North Carolina State University, Box 8009, Raleigh, NC 27695, USA.
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