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Abstract
The widely distributed, essential redox factor pyrroloquinoline quinone (PQQ, methoxatin) (1) was discovered in the mid-1960s. The breadth and depth of its biological effects are steadily being revealed, and understanding its biosynthesis at the genomic level is a continuing process. In this review, aspects of the chemistry, biology, biosynthesis, and commercial production of 1 at the gene level, and some applications, are presented from discovery through to mid-2021.
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Affiliation(s)
- Geoffrey A Cordell
- Natural Products Inc., Evanston, Illinois 60202, United States.,Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
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2
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Shiojima Y, Takahashi M, Takahashi R, Moriyama H, Bagchi D, Bagchi M, Akanuma M. Effect of Dietary Pyrroloquinoline Quinone Disodium Salt on Cognitive Function in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study. J Am Coll Nutr 2021; 41:796-809. [PMID: 34415830 DOI: 10.1080/07315724.2021.1962770] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
BACKGROUND Cognitive dysfunctions are increasing alarmingly around the world, and researchers are exploring preventive measures for improving brain performance. Pyrroloquinoline quinone (PQQ), a naturally occurring coenzyme in foods, exhibits potent antioxidant activity, and improves diverse functions which include mitochondrial activation, growth, repair, protection of nerve cells by increased expression of nerve growth factor (NGF) and NGF receptors; and suppression of fibril formation and aggregation of amyloid β. OBJECTIVE This randomized, double-blind, placebo-controlled, parallel-group clinical investigation (RCT) evaluated the efficacy and safety of PQQ disodium salt powder (mnemoPQQ®) for improved cognitive function after 12 weeks of supplementation in healthy Japanese male and female (age 40 to <80 Y). METHODS 64 healthy subjects were randomly assigned to receive either mnemoPQQ® (PQQ disodium salt: 21.5 mg/day) or a placebo over a period of 12 weeks. The efficacy of mnemoPQQ® on cognitive performance (memory, attention, judgment, and cognitive flexibility) was examined using Cognitrax as the primary outcome (primary endpoint), and forgetfulness questionnaire (DECO: Deterioration Cognitive Observee) and Mini-Mental State Examination-Japanese (MMSE-J) as the secondary outcome (secondary endpoint). RESULTS A total of 58 subjects (placebo = 31; Age = 70.91 ± 3.06 Y; mnemoPQQ® group = 27; Age = 72.10 ± 3.77 Y) completed the study over a period of 12 weeks of supplementation. Significant improvements were observed on the Cognitrax's cognitive function domain score on "composite memory", "verbal memory", "reaction time", "complex attention", "cognitive flexibility", "executive function", and "motor speed" in the mnemoPQQ® group as compared to the placebo group. The DECO and the MMSE-J scores were also significantly improved in the mnemoPQQ® group. No adverse events were observed. CONCLUSIONS Study demonstrates that supplementation of PQQ disodium salt is useful in improving memory, attention, judgment, and cognitive function, in middle-aged to elderly population, who feel they have become more forgetful because of aging.
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Affiliation(s)
| | - Megumi Takahashi
- Ryusendo Co., Ltd., R&D, Toshima-ku, Tokyo, Japan.,Laboratory of Ultrasound Theranostics, Faculty of Pharma Sciences, Teikyo University, Tokyo, Japan
| | - Ryohei Takahashi
- Ryusendo Co., Ltd., R&D, Toshima-ku, Tokyo, Japan.,Laboratory of Ultrasound Theranostics, Faculty of Pharma Sciences, Teikyo University, Tokyo, Japan
| | | | - Debasis Bagchi
- College of Pharmacy and Health Sciences, Texas Southern University, Houston, TX, USA
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3
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Hwang P, Willoughby DS. Mechanisms Behind Pyrroloquinoline Quinone Supplementation on Skeletal Muscle Mitochondrial Biogenesis: Possible Synergistic Effects with Exercise. J Am Coll Nutr 2018; 37:738-748. [DOI: 10.1080/07315724.2018.1461146] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Paul Hwang
- Department of Health, Human Performance, and Recreation, Exercise and Biochemical Nutrition Laboratory, Baylor University, Waco, Texas, USA
| | - Darryn S. Willoughby
- Department of Health, Human Performance, and Recreation, Exercise and Biochemical Nutrition Laboratory, Baylor University, Waco, Texas, USA
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4
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Turck D, Bresson JL, Burlingame B, Dean T, Fairweather-Tait S, Heinonen M, Hirsch-Ernst KI, Mangelsdorf I, McArdle HJ, Naska A, Neuhäuser-Berthold M, Nowicka G, Pentieva K, Sanz Y, Siani A, Sjödin A, Stern M, Tomé D, Vinceti M, Willatts P, Engel KH, Marchelli R, Pöting A, Poulsen M, Schlatter JR, de Sesmaisons A, Van Loveren H. Safety of pyrroloquinoline quinone disodium salt as a novel food pursuant to Regulation (EC) No 258/97. EFSA J 2017; 15:e05058. [PMID: 32625350 PMCID: PMC7010138 DOI: 10.2903/j.efsa.2017.5058] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) was asked to deliver an opinion on pyrroloquinoline quinone disodium salt (PQQ), trade name BioPQQ™, as a novel food pursuant to Regulation (EC) No 258/97. PQQ is produced by fermentation using Hyphomicrobium denitrificans CK-275 and purification process. PQQ has a minimum purity of 99.0%. The information provided on the composition, specifications, batch-to-batch variability, stability and production process of PQQ is sufficient and does not raise safety concerns. The applicant intends to market PQQ for use in food supplements for healthy adults, except pregnant and lactating women, at a maximum proposed level of consumption of 20 mg/day (corresponding to 0.29 mg/kg bw per day for a 70-kg person). The proposed level of consumption is at least 250 times higher than the estimated background intake of PQQ occurring naturally in foods. Information on the absorption, distribution, metabolism and excretion of PQQ in animals and humans is limited. Considering the no-observed-adverse-effect-level (NOAEL) of 100 mg/kg bw per day from a 90-day repeated dose oral toxicity study with BioPQQ™, and the maximum proposed level of consumption, the Panel concludes that the margin of exposure (of 344) is sufficient. The Panel concludes that the novel food, pyrroloquinoline quinone disodium salt (BioPQQ™), is safe under the intended conditions of use as specified by the applicant.
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Akagawa M, Nakano M, Ikemoto K. Recent progress in studies on the health benefits of pyrroloquinoline quinone. Biosci Biotechnol Biochem 2016; 80:13-22. [DOI: 10.1080/09168451.2015.1062715] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Abstract
Pyrroloquinoline quinone (PQQ), an aromatic tricyclic o-quinone, was identified initially as a redox cofactor for bacterial dehydrogenases. Although PQQ is not biosynthesized in mammals, trace amounts of PQQ have been found in human and rat tissues because of its wide distribution in dietary sources. Importantly, nutritional studies in rodents have revealed that PQQ deficiency exhibits diverse systemic responses, including growth impairment, immune dysfunction, and abnormal reproductive performance. Although PQQ is not currently classified as a vitamin, PQQ has been implicated as an important nutrient in mammals. In recent years, PQQ has been receiving much attention owing to its physiological importance and pharmacological effects. In this article, we review the potential health benefits of PQQ with a focus on its growth-promoting activity, anti-diabetic effect, anti-oxidative action, and neuroprotective function. Additionally, we provide an update of its basic pharmacokinetics and safety information in oral ingestion.
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Affiliation(s)
- Mitsugu Akagawa
- Department of Biological Chemistry, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Naka-ku, Sakai, Japan
| | - Masahiko Nakano
- Niigata Research Laboratory, Mitsubishi Gas Chemical Co., Inc., Niigata, Japan
| | - Kazuto Ikemoto
- Niigata Research Laboratory, Mitsubishi Gas Chemical Co., Inc., Niigata, Japan
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Acute and subchronic toxicity studies of pyrroloquinoline quinone (PQQ) disodium salt (BioPQQ™) in rats. Regul Toxicol Pharmacol 2014; 70:107-21. [DOI: 10.1016/j.yrtph.2014.06.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 06/23/2014] [Accepted: 06/24/2014] [Indexed: 11/23/2022]
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Ge X, Wang W, Du B, Wang J, Xiong X, Zhang W. Multiple pqqA genes respond differently to environment and one contributes dominantly to pyrroloquinoline quinone synthesis. J Basic Microbiol 2013; 55:312-23. [PMID: 23828377 DOI: 10.1002/jobm.201300037] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Accepted: 06/01/2013] [Indexed: 11/11/2022]
Abstract
Pyrroloquinoline quinone is the third redox cofactor after nicotinamide and flavin in bacteria, and its biosynthesis pathway comprise five steps initiated from a precursor peptide PqqA coded by pqqA gene. Methylovorus sp. MP688 is equipped with five copies of pqqA genes. Herein, the transcription of pqqA genes under different conditions by real-time quantitative PCR and β-galactosidase reporter genes are reported. Multiple pqqA genes were proved to play significant roles and contribute differently in PQQ synthesis. pqqA1, pqqA2, and pqqA4 were determined to be dominantly transcribed over the others, and correspondingly absence of any of the three genes caused a decrease in PQQ synthesis. Notably, pqqA was up-regulated in low pH and limited oxygen environment, and it is pqqA2 promoter that could be induced when bacteria were transferred from pH 7.0 to pH 5.5. Deletion analysis revealed a region within pqqA2 promoter inhibiting transcription. PQQ concentration was increased by overexpression of pqq genes under control of truncated pqqA2 promoter. The results not only imply there exist negative transcriptional regulators for pqqA2 but also provide us a new approach to achieve higher PQQ production by deleting the target binding sequence.
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Affiliation(s)
- Xin Ge
- Laboratory of Microorganism Engineering, Beijing Institute of Biotechnology, Beijing, China
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Kimura K, Takada M, Ishii T, Tsuji-Naito K, Akagawa M. Pyrroloquinoline quinone stimulates epithelial cell proliferation by activating epidermal growth factor receptor through redox cycling. Free Radic Biol Med 2012; 53:1239-51. [PMID: 22824864 DOI: 10.1016/j.freeradbiomed.2012.07.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 07/02/2012] [Accepted: 07/16/2012] [Indexed: 01/08/2023]
Abstract
Pyrroloquinoline quinone (PQQ), a redox cofactor for bacterial dehydrogenases, has been implicated to be an important nutrient in mammals functioning as a potent growth factor. However, the underlying molecular mechanisms have not been elucidated. The present study revealed that PQQ induces the activation (tyrosine autophosphorylation) of epidermal growth factor receptor (EGFR) and its downstream signaling in a ligand-independent manner, leading to increased cellular proliferation in an epithelial cell line A431. PQQ inhibited protein tyrosine phosphatase 1B (PTP1B), which negatively regulates the EGFR signaling by tyrosine dephosphorylation, to oxidatively modify the catalytic cysteine through its redox cycling activity to generate H(2)O(2). PQQ-inducible intracellular ROS production and EGFR activation were significantly suppressed by the pre-treatment with antioxidants. The intracellular redox state regulates the EGFR signaling through the redox-sensitive catalytic cysteine of PTP1B and modulates cell proliferation. Our data suggest that PQQ may stimulate epithelial cell proliferation by activating EGFR by oxidation and subsequent inactivation of PTP1B via its redox cycling. Our results provide novel insight into the mechanisms by which PQQ may function as a growth factor to contribute to mammalian growth.
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Affiliation(s)
- Kazuki Kimura
- Department of Biological Chemistry, Division of Applied Life Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai 599-8531, Japan
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Identification of transcriptional networks responding to pyrroloquinoline quinone dietary supplementation and their influence on thioredoxin expression, and the JAK/STAT and MAPK pathways. Biochem J 2010; 429:515-26. [PMID: 20491655 PMCID: PMC2907713 DOI: 10.1042/bj20091649] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PQQ (pyrroloquinoline quinone) improves energy utilization and reproductive performance when added to rodent diets devoid of PQQ. In the present paper we describe changes in gene expression patterns and transcriptional networks that respond to dietary PQQ restriction or pharmacological administration. Rats were fed diets either deficient in PQQ (PQQ−) or supplemented with PQQ (approx. 6 nmol of PQQ/g of food; PQQ+). In addition, groups of rats were either repleted by administering PQQ to PQQ− rats (1.5 mg of PQQ intraperitoneal/kg of body weight at 12 h intervals for 36 h; PQQ−/+) or partially depleted by feeding the PQQ− diet to PQQ+ rats for 48 h (PQQ+/−). RNA extracted from liver and a Codelink® UniSet Rat I Bioarray system were used to assess gene transcript expression. Of the approx. 10000 rat sequences and control probes analysed, 238 were altered at the P<0.01 level by feeding on the PQQ− diet for 10 weeks. Short-term PQQ depletion resulted in changes in 438 transcripts (P<0.01). PQQ repletion reversed the changes in transcript expression caused by PQQ deficiency and resulted in an alteration of 847 of the total transcripts examined (P<0.01). Genes important for cellular stress (e.g. thioredoxin), mitochondriogenesis, cell signalling [JAK (Janus kinase)/STAT (signal transducer and activator of transcription) and MAPK (mitogen-activated protein kinase) pathways] and transport were most affected. qRT-PCR (quantitative real-time PCR) and functional assays aided in validating such processes as principal targets. Collectively, the results provide a mechanistic basis for previous functional observations associated with PQQ deficiency or PQQ administered in pharmacological amounts.
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Noji N, Nakamura T, Kitahata N, Taguchi K, Kudo T, Yoshida S, Tsujimoto M, Sugiyama T, Asami T. Simple and sensitive method for pyrroloquinoline quinone (PQQ) analysis in various foods using liquid chromatography/electrospray-ionization tandem mass spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:7258-63. [PMID: 17685628 DOI: 10.1021/jf070483r] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Pyrroloquinoline quinone (PQQ) is believed to be an important factor for mammalian growth and development and has, therefore, been declared a vitamin by some researchers. However, this issue remains controversial, and from a nutritional viewpoint, accurate determination of PQQ levels in a variety of foods is very important. Here, we describe a simple, highly sensitive, and highly selective method for quantitative analysis of PQQ. Liquid foods or aqueous extracts of solid foods were analyzed using high-performance liquid chromatography (HPLC) combined with electrospray-ionization (ESI) tandem mass spectrometry (MS/MS). (15)N-labeled PQQ was added to the samples as an internal standard. Quantitative analyses of PQQ were performed by multiple reaction monitoring (MRM) with LC/MS/MS. Free PQQ was detected in almost all food samples in the range 0.19-7.02 ng per g fresh weight (for solid foods) or per mL (liquid foods). This method will enable the rapid and simple determination of PQQ levels in many samples.
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Affiliation(s)
- Natsumi Noji
- Graduate School of Agriculture, Meiji University, DRI, RIKEN, PSC, RIKEN, Japan
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He K, Nukada H, Urakami T, Murphy MP. Antioxidant and pro-oxidant properties of pyrroloquinoline quinone (PQQ): implications for its function in biological systems. Biochem Pharmacol 2003; 65:67-74. [PMID: 12473380 DOI: 10.1016/s0006-2952(02)01453-3] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Pyrroloquinoline quinone (PQQ) is a novel redox cofactor recently found in human milk. It has been reported to function as an essential nutrient, antioxidant and redox modulator in cell culture experiments and in animal models of human diseases. As mitochondria are particularly susceptible to oxidative damage we studied the antioxidant properties of PQQ in isolated rat liver mitochondria. PQQ was an effective antioxidant protecting mitochondria against oxidative stress-induced lipid peroxidation, protein carbonyl formation and inactivation of the mitochondrial respiratory chain. In contrast, PQQ caused extensive cell death to cells in culture. This surprising effect was inhibited by catalase, and was shown to be due to the generation of hydrogen peroxide during the autoxidation of PQQ in culture medium. We conclude that the reactivities of PQQ are dependent on its environment and that it can act as an antioxidant or a pro-oxidant in different biological systems.
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Affiliation(s)
- Kai He
- Department of Medical and Surgical Sciences, Dunedin School of Medicine, University of Otago, P.O. Box 56, Dunedin, New Zealand
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12
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Abstract
Pyrroloquinoline quinone (PQQ), otherwise known as methoxatin, is a water-soluble, redox-cycling orthoquinone that was initially isolated from cultures of methylotropic bacteria. It has been found to be a cofactor of some bacterial alcohol dehydrogenases, and is present in many animal tissues. It may be a novel vitamin because it has been shown to be essential for normal growth and development. The redox-cycling ability of PQQ enables it to scavenge or generate superoxide. When fed to animals as a supplement, PQQ prevents oxidative changes that would ordinarily occur. It has been reported to inhibit glutamate decarboxylase activity and protect against N-methyl-D-aspartate (NMDA) receptor-mediated neurotoxicity in the brain. It appears that in the whole animal, however, PQQ does not cross the blood-brain barrier. Furthermore, it increases nerve growth factor (NGF) synthesis in mouse astroglial cells, but has to be bound to glycine to penetrate and exert this effect in whole brain. It may therefore be regarded as a "Janus faced" molecule, with its potential for a therapeutic role in the brain still in question.
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Affiliation(s)
- A Bishop
- Department of Molecular and Cellular Toxicology, Harvard School of Public Health, Boston, MA, USA
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McIntire WS. Newly discovered redox cofactors: possible nutritional, medical, and pharmacological relevance to higher animals. Annu Rev Nutr 1998; 18:145-77. [PMID: 9706222 DOI: 10.1146/annurev.nutr.18.1.145] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Research spurred by the discovery of pyrroloquinoline quinone (PPQ) in 1979 led to the discovery of four additional oxidation-reduction (redox) cofactors, all of which result from transmogrification of amino acyl side chains in respective enzymes. These cofactors are (a) topa quinone in copper-containing amine oxidases, enzymes found in nearly all forms of life, including human; (b) lysyl topa quinone of the copper protein lysyl oxidase, an enzyme required for proper cross-linking of collagen and elastin; (c) tryptophan tryptophylquinone of alkylamine dehydrogenases from gram-negative soil bacteria; and (d) the copper-complexed cysteinyltyrosyl radical of fungal galactose oxidase. Originally, PQQ was thought to be a covalently bound cofactor in numerous enzymes from eukaryotes and prokaryotes. Today, PQQ is only found as a noncovalent cofactor in bacterial enzymes. The ubiquity of PQQ in the environment and its steady accessibility in the human diet has raised questions concerning its role as a vitamin, or an essential or helpful nutrient. The relevance to nutrition, medicine, and pharmacology of PQQ, topa quinone, lysyl topa quinone, tryptophan trytophylquinone, the galactose oxidase cofactor, and the enzymes harboring these cofactors are discussed in this review.
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Affiliation(s)
- W S McIntire
- Department of Veterans Affairs Medical Center, San Francisco, California 94121, USA.
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Misset-Smits M, Oltshoorn AJ, Dewanti A, Duine JA. Production, assay, and occurrence of pyrroloquinoline quinone. Methods Enzymol 1997; 280:89-98. [PMID: 9211309 DOI: 10.1016/s0076-6879(97)80105-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- M Misset-Smits
- Department of Microbiology and Enzymology, Delft University of Technology, The Netherlands
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Suzuki O, Kumazawa T. Gas chromatographic-mass spectrometric analysis of pyrroloquinoline quinone. Methods Enzymol 1997; 280:150-8. [PMID: 9211311 DOI: 10.1016/s0076-6879(97)80107-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- O Suzuki
- Department of Legal Medicine, Hamamatsu University School of Medicine, Japan
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Kumazawa T, Sato K, Seno H, Ishii A, Suzuki O. Levels of pyrroloquinoline quinone in various foods. Biochem J 1995; 307 ( Pt 2):331-3. [PMID: 7733865 PMCID: PMC1136652 DOI: 10.1042/bj3070331] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The levels of free pyrroloquinoline quinone (PQQ) in various foods were examined by the use of gas chromatography-mass spectrometry. PQQ was extracted from the samples, after addition of [U-13C]PQQ as internal standard, with n-butanol and Sep-Pak C18 cartridges. After derivatization of PQQ with phenyltrimethylammonium hydroxide, molecular peaks at m/z 448 and 462 were used for detection of PQQ and [U-13C]PQQ respectively, by selected ion monitoring. Free PQQ could be detected in every sample in the range 3.7-61 ng/g or ng/ml. Since its levels in human tissues and body fluids are 5-10 times lower than those found in foods, it is probable that PQQ existing in human tissues is derived, at least partly, from the diet.
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Affiliation(s)
- T Kumazawa
- Department of Legal Medicine, Showa University School of Medicine, Tokyo, Japan
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