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Árpád Könczöl, Kata Rendes, Miklós Dékány, Judit Müller, Eszter Riethmüller, György Tibor Balogh
The linkage between the central nervous system availability and neuropharmacological activity of the constituents of Ginkgo biloba L. extracts (GBE) is still incomplete. In this study, the in vitro blood-brain barrier (BBB) permeability profile of the standardised GBE was investigated by the parallel artificial membrane permeability assay (PAMPA). Biomarkers, such as terpene trilactones, flavonoid aglycones and ginkgotoxin exerted moderate or good BBB-permeability potential (BBB+), while glycosides and biflavones were predicted as unable to pass the BBB...
November 30, 2016: Journal of Pharmaceutical and Biomedical Analysis
Irina Steiner, Gernot Brauers, Oliver Temme, Thomas Daldrup
We present the determination of the alkaloid hordenine and its forensic relevance as a qualitative and quantitative marker for beer consumption. A simple, rapid and sensitive ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) method for the determination of hordenine in human serum samples was developed and validated. The application was tested with serum samples after enzymatic cleavage. After addition of the synthesized internal standard hordenine-D 4, a liquid-liquid extraction with dichloromethane and diethyl ether was performed...
March 2016: Analytical and Bioanalytical Chemistry
Ashton D Lesiak, Robert B Cody, Masaaki Ubukata, Rabi A Musah
We demonstrate the utility of direct analysis in real time ionization coupled with high resolution time-of-flight mass spectrometry (DART-HRTOFMS) in revealing the adulteration of commercially available Sceletium tortuosum, a mind-altering plant-based drug commonly known as Kanna. Accurate masses consistent with alkaloids previously isolated from S. tortuosum plant material enabled identification of the products as Kanna, and in-source collision-induced dissociation (CID) confirmed the presence of one of these alkaloids, hordenine, while simultaneously revealing the presence of an adulterant...
March 2016: Forensic Science International
Carine Viana, Gabriela M Zemolin, Larissa S Müller, Thaís R Dal Molin, Helena Seiffert, Leandro M de Carvalho
Methyl-xanthines and adrenergic stimulants, such as caffeine and synephrine, are commonly added to food supplements due to their stimulating and thermogenic effects. In addition, the abusive consumption of food supplements with ergogenic and aesthetic purposes has been observed worldwide. This work describes the study of caffeine, p-synephrine, hordenine, octopamine, tyramine, ephedrine and salicin as stimulants in dietary supplements marketed in Brazil for weight loss and physical fitness claims. A total of 94 different products were acquired from 30 Brazilian websites...
2016: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
Nícolas de Castro Campos Pinto, Ana Paula do Nascimento Duque, Natália Ramos Pacheco, Renata de Freitas Mendes, Erick Vicente da Silva Motta, Paula Maria Quaglio Bellozi, Antônia Ribeiro, Marcos José Salvador, Elita Scio
CONTEXT: Pereskia aculeata Miller (Cactaceae) is a cactus distributed from south to northeast of Brazil, where its leaves are commonly used as a vegetable, in skin wound healing, and to treat inflammation. OBJECTIVES: The objective of this study was to perform the chemical characterization and to evaluate the antinociceptive activity of the hydromethanolic fraction obtained from the methanol extract of P. aculeata leaves. MATERIALS AND METHODS: Chemical characterization was performed by UPLC-MS analysis...
2015: Pharmaceutical Biology
Jianshe Ma, Shuanghu Wang, Xueli Huang, Peiwu Geng, Congcong Wen, Yunfang Zhou, Linsheng Yu, Xianqin Wang
Hordenine is an active compound found in several foods, herbs and beer. In this work, a sensitive and selective UPLC-MS/MS method for determination of hordenine in rat plasma was developed. After addition of caulophylline as internal standard (IS), protein precipitation by acetonitrile-methanol (9:1, v/v) was used as sample preparation. Chromatographic separation was achieved on a UPLC BEH HILIC (2.1 mm × 100 mm, 1.7 μm) with acetonitrile (containing 10mM ammonium formate) and water (containing 0.1% formic acid and 10 mM ammonium formate) as mobile phase with gradient elution...
2015: Journal of Pharmaceutical and Biomedical Analysis
Shuanghu Wang, Haiya Wu, Xueli Huang, Peiwu Geng, Congcong Wen, Jianshe Ma, Yunfang Zhou, Xianqin Wang
In this work, a sensitive and selective UPLC-MS/MS method for determination of N-methylcytisine in rat plasma is developed. After addition of hordenine as an internal standard (IS), protein precipitation by acetonitrile-methanol (9:1, v/v) was used to prepare samples. Chromatographic separation was achieved on a UPLC BEH HILIC (2.1 mm×100mm, 1.7μm) with acetonitrile (containing 10mM ammonium formate) and water (containing 0.1% formic acid and 10mM ammonium formate) as the mobile phase with gradient elution...
May 15, 2015: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Yonggang Chen, Junhua Meng, Jili Zou, Jing An
Hordenine is an active compound found in several foods, herbs and beer. In this work, a novel sorbent was fabricated for selective solid-phase extraction (SPE) of hordenine in biological samples. The organic polymer sorbent was synthesized in one step in the plastic barrel of a syringe by a pre-polymerization solution consisting of methacrylic acid (MAA), 4-vinylphenylboronic acid (VB) and ethylene glycol dimethacrylate (EGDMA). The conditions for preparation were optimized to generate a poly(MAA-VB-EGMDA) monolith with good permeability...
June 2015: Biomedical Chromatography: BMC
Amélie Beury-Cirou, Mélanie Tannières, Corinne Minard, Laurent Soulère, Tsiry Rasamiravaka, Robert H Dodd, Yves Queneau, Yves Dessaux, Catherine Guillou, Olivier M Vandeputte, Denis Faure
N-acylhomoserine lactone (AHL)-mediated quorum-sensing (QS) regulates virulence functions in plant and animal pathogens such as Agrobacterium tumefaciens and Pseudomonas aeruginosa. A chemolibrary of more than 3500 compounds was screened using two bacterial AHL-biosensors to identify QS-inhibitors (QSIs). The purity and structure of 15 QSIs selected through this screening were verified using HPLC MS/MS tools and their activity tested on the A. tumefaciens and P. aeruginosa bacterial models. The IC50 value of the identified QSIs ranged from 2...
2013: PloS One
Frank Musshoff, Lidia Hottmann, Cornelius Hess, Burkhard Madea
The appearance of dangerous and insufficiently studied designer drugs has increased substantially within the last few years. Mixtures containing centrally active compounds are often declared as "bath salt", "incense", "plant food", "bong cleaners" and are marketed in head shops and on the Internet. As the majority of the ingredients of such products are not subject to regulations of the German Narcotics Law (Betäubungsmittelgesetz, BtMG), the vendors and consumers mistake the sale of such products for legal...
September 2013: Archiv Für Kriminologie
E Meyer
Hordenine is biosynthesized in young roots of barley by subsequent N-methylation of tyramine. It was shown that two distinct enzymes are responsible for these methylation reactions. They differed in their pH-optimum, their stability in dependence of the pH-value, and were partially resolved by DEAE-chromatography. More than 200-fold purification and almost complete separation were achieved by elution of the enzymes from an affinity column which was prepared by coupling S-adenosylhomocysteine to aminohexyl-Sepharose 4 B...
December 1982: Plant Cell Reports
A H Hoult, J V Lovett
A method was devised for the extraction and quantification of hordenine and gramine from barley (Hordeum vulgare) tissue using HPLC techniques. Quantification was by peak area, the relationship between peak area and concentration of authentic standards being linear for both hordenine and gramine. Significant differences in the ability of three lines of barley to produce hordenine and gramine were detected using this method.
October 1993: Journal of Chemical Ecology
D L Liu, J V Lovett
The release of alkaloids by barley was quantified by HPLC. Hordenine was released from the roots of barley in a hydroponic system for up to 60 days. The amount reached a maximum, 2μg/plant/day, at 36 days, then declined. Effects on white mustard by hordenine and gramine included reduction of radicle length and apparent reduction in health and vigor of radicle tips. Transmission electron microscopic examination of white mustard radicle tips exposed to hordenine and gramine showed damage to cell walls, increase in both size and number of vacuoles, autophagy, and disorganization of organelles...
October 1993: Journal of Chemical Ecology
J V Lovett, A H Hoult, O Christen
Forty-three lines of barley, including ancestral (wild), landraces, Middle Eastern lines, and modern cultivars, were grown under two different sets of environmental conditions. Hordenine production in barley roots was determined at the one-leaf stage by HPLC analysis and, in two lines only, over a period of 35 days. Forty-two of the 43 lines produced significant amounts of hordenine, although there was no variation among groups. Middle Eastern lines had the highest production with 327 µg/g on a dry weight basis...
August 1994: Journal of Chemical Ecology
Sang-Cheol Kim, Jin-Hyunk Lee, Moo-Han Kim, Jung-A Lee, Yum Beom Kim, Eunsun Jung, Young-Soo Kim, Jongsung Lee, Deokhoon Park
Melanin plays an important role protecting skin against ultraviolet light injury. However, increased production and accumulation of melanin results in a large number of skin disorders. Here, we identified hordenine as an active compound from germinated barley (Hordeum vulgare L.) and investigated the effects of hordenine on melanogenesis and its mechanisms of action in human epidermal melanocytes. We measured melanin content, tyrosinase activity, expression of melanogenesis-related proteins, and cAMP production...
November 1, 2013: Food Chemistry
Carine Viana, Gabriela M Zemolin, Fernanda O Lima, Leandro M de Carvalho, Carla B G Bottoli, Renata Pereira Limberger
A reverse-phase (RP)-HPLC method is reported for determining L-tyrosine, p-octopamine, synephrine, tyramine and hordenine as chemical markers of the species Citrus aurantium in raw material, dry extracts and phytotherapeutic herbal formulations. Using RP-HPLC with diode array detection (DAD) and gradient elution, the amines were determined in 12 different products from different Brazilian states labelled as containing C. aurantium. The presence of the amines was confirmed by mass spectrometry using electrospray ionisation (ESI-MS/MS)...
2013: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
J R H Archer, P I Dargan, S Hudson, D M Wood
AIM: Analysis of urine samples collected across a city centre, for the detection of novel psychoactive substances (NPS). DESIGN: Cross-sectional study of anonymized urine samples used for the analysis of classical recreational drugs, NPS and metabolites. METHODS: Pooled urine samples collected from portable stand-alone four-person urinals across a city centre were analysed using full-scan accurate-mass high-resolution liquid chromatography coupled to tandem mass spectrometry...
February 2013: QJM: Monthly Journal of the Association of Physicians
Mario Thevis, Hans Geyer, Gerd Sigmund, Wilhelm Schänzer
Manipulation of urine specimens provided by elite athletes for doping control purposes has been reported several times in the past, and in most of these cases urine substitution was eventually proven. Recent findings of suspected and substantiated manipulation have outlined the complexity and diversity of tampering options, sample appearance alterations resulting from non-manipulative influence, and the analytical challenges arising from these scenarios. Using state-of-the-art mass spectrometric and immunological doping control and forensic chemistry methodologies, four unusual findings were observed...
January 5, 2012: Journal of Pharmaceutical and Biomedical Analysis
Strahil Berkov, Jaume Bastida, Borjana Sidjimova, Francesc Viladomat, Carles Codina
Seventy alkaloids of galanthamine, lycorine, homolycorine, tazettine, haemanthamine, narciclasine, and tyramine types were detected by GC/MS in 25 Galanthus elwesii and seven Galanthus nivalis populations, collected from different locations in Bulgaria. Intraspecies diversity in the alkaloid profiles regarding the main alkaloid types (chemotypes) was observed. Tyramine-type protoalkaloids (namely, hordenine and its derivatives) were dominant in 19 populations of G. elwesii. In other populations of G. elwesii, the plants accumulated mainly homolycorine-, lycorine-, and galanthamine-type alkaloids...
January 2011: Chemistry & Biodiversity
Daopeng Tan, Ying Chen, Lili Ji, Guixin Chou, Zhengtao Wang
OBJECTIVE: To investigate the alkaloids from Senecio scandens. METHOD: Compounds were isolated with silica gel and Sephadex LH-20 column chromatography and their structures were determined by spectral analysis and chemical evidence. The hepatic cytotoxicity of isolated compounds was tested by MTT method in vitro. RESULT: Six alkaloids were obtained and identified as adonifoline (1), 7-angeloylturneforcidine (2), hordenine (3), 1, 3, 6, 6-tetramethyl-5, 6, 7, 8-tetrahydro-isoquinolin-8-one (4), 4-(pyrrolidin-2-one) -phenyl acetic acid (5), (4-pyrrolidinophenyl) acetic acid (6)...
October 2010: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
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