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1.
J Ethnopharmacol ; 278: 114202, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33991640

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Griffonia simplicifolia D.C (Baill.) (Fabaceae) seeds are unusually high (6-20% wet weight) in 5-HTP (5-Hydroxytryptophan), a serotonin precursor widely used to treat depression. Consequently, this species is regarded as a herbal "Prozac®". Contemporary use as an anti-depressant contrasts with traditional uses for insecticides, arachnicides, fodder, dyes, mordants and chewing-sticks. G. simplicifolia seeds are wild-harvested for the export trade. Over the past 15 years, use of 5-HTP extracted from G. simplicifolia in cosmetics has added to global demand. Wild populations in West Africa are the sole commercial source of G. simplicifolia seed. AIMS OF THE STUDY: Were to (i) assess the scale of the global trade in G. simplicifolia seeds and (ii) produce a synthesis of the challenges facing sustainable harvest of G. simplicifolia. MATERIALS AND APPROACH: Firstly, we analysed global trade data for G. simplicifolia, taking into account historical trends over the past 40 years. Secondly, we reviewed published studies on the distribution, population biology and harvest impacts of wild G. simplicifolia populations. RESULTS AND CONCLUSION: s: Wild G. simplicifolia populations have been the focus of commercial harvest of their pods (for seeds) for international trade from West Africa for almost 50 years. In the late 1980's, when Ghana exported 75-80 metric tonnes (MT) of G. simplicifolia seed to Europe, this species was already Ghana's main medicinal plant export. Currently, 5 West African countries export G. simplicifolia seeds (Cote d'Ivoire, Ghana, Liberia, Nigeria and Togo). Although in the 1980's, most seed exports were to Europe, today China is the main importer of G. simplicifolia seed. These seeds are value-added for production of 5-HTP extracts, and then re-exported, particularly to North America (c.48% of exports). The low habitat specificity and vigorous re-sprouting of G. simplicifolia after cutting, plus its occurrence in forest reserves and national parks confer some resilience on wild populations. Sustaining future supply chains faces six future challenges, however: (1) Rapid loss of forest habitats; (2) Declining populations of understorey birds and disruption of G. simplicifolia pollination in this bird pollinated species; (3) Negative effects of introduced invasive plant species (Broussonetia papyrifera, Chromolaena odorata) on G. simplicifolia regeneration; (4) Grazing by livestock and use of G. simplicifolia leaves as forage; (5) The long-term impact of industrial scale seed "predation": Over a 9-year period (2005-2013), G. simplicifolia exports from Ghana totalled at least 5550 metric tonnes (or between 9.1 billion to 13.5 billion seeds). This could affect the long-term population dynamics of this species, which produces a low number of seeds per pod (1-4 seeds) and has short distance (ballistic) seed dispersal; and (6) Destructive harvest methods, when plants are cut to harvest get the seed pods. Improved resource management, monitoring, quality control and careful pricing are important if supply chains from wild stocks are to be maintained. If wild populations decline, then 5-HTP biosynthesis may compete with low G. simplicifolia seed yields, leading to loss of income to West African harvesters and traders.


Assuntos
5-Hidroxitriptofano/isolamento & purificação , Griffonia/química , Extratos Vegetais/provisão & distribuição , 5-Hidroxitriptofano/provisão & distribuição , Animais , Antidepressivos de Segunda Geração/isolamento & purificação , Antidepressivos de Segunda Geração/provisão & distribuição , Comércio/tendências , Conservação dos Recursos Naturais , Florestas , História do Século XX , História do Século XXI , Humanos , Medicina Tradicional/métodos , Extratos Vegetais/química , Sementes
2.
Biosci Biotechnol Biochem ; 83(10): 1800-1806, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31131717

RESUMO

Tyrosinase is the key enzyme that controls melanin formation. We found that a hot water extract of the lyophilized fruiting body of the fungus Lyophyllum decastes inhibited tyrosinase from Agaricus bisporus. The extract was fractionated by ODS column chromatography, and an active compound was obtained by purification through successive preparative HPLC using an ODS and a HILIC column. Using spectroscopic data, the compound was identified to be an uncommon amino acid, 6-hydroxytryptophan. 6-Hydroxy-L-tryptophan and 6-hydroxy-D-tryptophan were prepared through a Fenton reaction from L-tryptophan and D-tryptophan, respectively. The active compound was determined to be 6-hydroxy-L-tryptophan by comparison of their circular dichroism spectra and retention time on HPLC analysis of the Nα-(5-fluoro-2,4-dinitrophenyl)-L-leuciamide derivative with those of 6-hydroxy-L-tryptophan and 6-hydroxy-D-tryptophan. A Lineweaver-Burk plot of the enzyme reaction in the presence of 6-hydroxy-L-tryptophan indicated that this compound was a competitive inhibitor. The IC50 values of 6-hydroxy-L-tryptophan was 0.23 mM.


Assuntos
5-Hidroxitriptofano/isolamento & purificação , Agaricales/metabolismo , Inibidores Enzimáticos/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , 5-Hidroxitriptofano/farmacologia , Cromatografia Líquida de Alta Pressão , Concentração Inibidora 50
3.
PLoS Negl Trop Dis ; 10(12): e0005140, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27941966

RESUMO

Treatment for human African trypanosomiasis is dependent on the species of trypanosome causing the disease and the stage of the disease (stage 1 defined by parasites being present in blood and lymphatics whilst for stage 2, parasites are found beyond the blood-brain barrier in the cerebrospinal fluid (CSF)). Currently, staging relies upon detecting the very low number of parasites or elevated white blood cell numbers in CSF. Improved staging is desirable, as is the elimination of the need for lumbar puncture. Here we use metabolomics to probe samples of CSF, plasma and urine from 40 Angolan patients infected with Trypanosoma brucei gambiense, at different disease stages. Urine samples provided no robust markers indicative of infection or stage of infection due to inherent variability in urine concentrations. Biomarkers in CSF were able to distinguish patients at stage 1 or advanced stage 2 with absolute specificity. Eleven metabolites clearly distinguished the stage in most patients and two of these (neopterin and 5-hydroxytryptophan) showed 100% specificity and sensitivity between our stage 1 and advanced stage 2 samples. Neopterin is an inflammatory biomarker previously shown in CSF of stage 2 but not stage 1 patients. 5-hydroxytryptophan is an important metabolite in the serotonin synthetic pathway, the key pathway in determining somnolence, thus offering a possible link to the eponymous symptoms of "sleeping sickness". Plasma also yielded several biomarkers clearly indicative of the presence (87% sensitivity and 95% specificity) and stage of disease (92% sensitivity and 81% specificity). A logistic regression model including these metabolites showed clear separation of patients being either at stage 1 or advanced stage 2 or indeed diseased (both stages) versus control.


Assuntos
Biomarcadores/análise , Trypanosoma brucei gambiense/metabolismo , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/parasitologia , 5-Hidroxitriptofano/sangue , 5-Hidroxitriptofano/líquido cefalorraquidiano , 5-Hidroxitriptofano/isolamento & purificação , 5-Hidroxitriptofano/urina , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/urina , Barreira Hematoencefálica , Feminino , Humanos , Masculino , Metabolômica/métodos , Neopterina/sangue , Neopterina/líquido cefalorraquidiano , Neopterina/isolamento & purificação , Neopterina/urina , Análise de Regressão , Sensibilidade e Especificidade , Adulto Jovem
4.
Phytomedicine ; 17(12): 987-91, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20359873

RESUMO

At present Griffonia simplicifolia is used in food supplement aimed to treat mood disorders as well as to reduce food intake and body weight. The plant has gained increasing interest for its high content in 5-hydroxy-L-tryptophan (5-HTP) particularly in the seed. The present study was designed to evaluate the influence of a seed extract of the plant, dosed at 25, 50 and 100 mg/kg, on the sexual behavior of ovariectomized hormone-primed rats after acute and subchronic treatment. The single administration of G. simplicifolia significantly reduced lordosis response and increased rejection behavior in female rats treated with the highest dose while it did not influence proceptive behaviors. On the other hand the subchronic administration of the extract significantly reduced proceptivity but not receptivity, and increased rejection behavior. All the tested dosages were able to markedly decrease food intake and body weight after a 9-day treatment. Taken together the present results, possibly ascribed to increased levels of 5-hydroxytryptamine (5-HT) in the brain, suggest a cautious administration of the plant extract owing to its negative influence on female sexual behavior.


Assuntos
5-Hidroxitriptofano/farmacologia , Griffonia/química , Comportamento Sexual Animal/efeitos dos fármacos , 5-Hidroxitriptofano/isolamento & purificação , Animais , Peso Corporal/efeitos dos fármacos , Ingestão de Energia/efeitos dos fármacos , Feminino , Masculino , Ovariectomia , Ratos , Ratos Sprague-Dawley , Sementes
5.
Proc Natl Acad Sci U S A ; 100(7): 3853-7, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12629208

RESUMO

Although analysis strategies exist for probing a diverse array of molecular properties, most of these approaches are not amenable to the study of reaction intermediates and other transient species. Separations in particular can provide detailed information on attributes not readily measured by spectroscopy but typically are performed over time scales much longer than the life span of highly unstable compounds. Here we report the development of an electrophoretic strategy that dramatically extends the practical speed limit for fractionations and demonstrate its utility in examining transient hydroxyindole photoproducts. Fluorescent reaction intermediates are optically generated in femtoliter volumes within a flowing reagent stream and are differentially transported at velocities as large as 1.3 m.s(-1), thereby minimizing band variance and allowing multicomponent reaction mixtures to be resolved over separation paths as short as 9 microm. Analyte migration times and band variances do not deviate significantly from basic theory for separations performed with fields that exceed 0.1 MV.cm(-1), indicating that effects from Joule heating are minor. We demonstrate the feasibility of achieving baseline resolution of a binary mixture in <10 micros, nearly 100-fold faster than previously possible. Application of this approach to the study of a range of short-lived molecules should be feasible.


Assuntos
5-Hidroxitriptofano/isolamento & purificação , Aminas Biogênicas/isolamento & purificação , Eletroforese/métodos , Eletroforese/instrumentação , Desenho de Equipamento , Cinética , Fotoquímica , Serotonina/isolamento & purificação , Fatores de Tempo
6.
Phytochem Anal ; 13(6): 333-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12494751

RESUMO

5-Hydroxytryptophan (1) is a naturally occurring amino acid found in significant levels in seeds of Griffonia simplicifolia and used in the treatment of the numerous effects of serotonin deficiency syndrome. An HPLC method has been developed for the direct assay of 1 in seeds of G. simplicifolia which overcomes the problems associated with previous techniques. By optimising the solvent extraction procedures and the HPLC conditions, levels of 1 could be estimated following a single-step seed extraction. The chromatographic conditions, solvent system and the extraction technique developed make this method relatively simple, fast and efficient. Using the described methods, the highest ever levels of 1 (namely, 20.83% on a fresh weight basis) have been determined in seeds of G. simplicifolia obtained in Ghana.


Assuntos
5-Hidroxitriptofano/química , Griffonia/química , Sementes/química , Serotonina/biossíntese , 5-Hidroxitriptofano/isolamento & purificação , 5-Hidroxitriptofano/metabolismo , Algoritmos , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Sementes/metabolismo
7.
Biomed Chromatogr ; 14(3): 205-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10850626

RESUMO

Tryptophan and its metabolites, 5-hydroxytryptophan, 5-hydroxytryptamine, 5-hydroxyindolacetic acid, as well as dopamine, homovanilic acid and 2,3-dihydroxyphenylacetic acid, were separated on phenyl bound silica gel using isocratic elution with phosphate buffer. The method was successfully transferred to several other phenyl HPLC columns from different manufacturers simply by adjusting the pH of the buffer. The method has been validated by the determination of the level of monoamines in rat hypothalamus.


Assuntos
Monoaminas Biogênicas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Ácido 3,4-Di-Hidroxifenilacético/isolamento & purificação , 5-Hidroxitriptofano/isolamento & purificação , Animais , Dopamina/isolamento & purificação , Ácido Homovanílico/isolamento & purificação , Ácido Hidroxi-Indolacético/isolamento & purificação , Hipotálamo/química , Ratos , Serotonina/isolamento & purificação , Triptofano/isolamento & purificação
8.
J Biol Chem ; 268(17): 12544-51, 1993 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7685343

RESUMO

Mouse bone marrow-derived mast cells (BMMC) store and release serotonin whose synthesis is initiated by tryptophan 5-monooxygenase. (6R)-H4biopterin serves as the natural cofactor for this reaction. GTP cyclohydrolase I catalyzes the first and rate-limiting step of its synthesis. In this study we demonstrate that among a panel of growth-promoting cytokines including kit ligand (KL), interleukin 3 (IL-3), IL-4, IL-9, and nerve growth factor, KL selectively enhances the synthesis of H4biopterin through up-regulation of GTP cyclohydrolase I activity to 6.2-fold levels. The activities of the subsequent enzymes 6-pyruvoyl-H4pterin synthase and sepiapterin reductase remain unaffected. The activity of tryptophan 5-monooxygenase was selectively enhanced 4.5-fold by the combination of IL-3 with KL. All other factors could not substitute for KL. The constitutive high activity of aromatic L-amino acid decarboxylase is not different in cells cultured in IL-3 and/or KL. In consequence, the concerted action of IL-3 and KL on the GTP cyclohydrolase I and the tryptophan 5-monooxygenase reaction enhances the production of serotonin to about 20-fold levels. Additionally, KL specifically causes the release of about half of total serotonin produced. Hence, our data demonstrate a novel role of these cytokines for the function of mouse BMMC and provide a coherent view of the regulation of serotonin synthesis in this cell type.


Assuntos
Medula Óssea/enzimologia , GTP Cicloidrolase/metabolismo , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Interleucina-3/farmacologia , Mastócitos/enzimologia , Serotonina/metabolismo , Triptofano Hidroxilase/metabolismo , 5-Hidroxitriptofano/isolamento & purificação , 5-Hidroxitriptofano/metabolismo , Animais , Biopterinas/isolamento & purificação , Biopterinas/metabolismo , Células da Medula Óssea , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Interleucina-4/farmacologia , Cinética , Mastócitos/citologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Biológicos , Proteínas Recombinantes/farmacologia , Serotonina/biossíntese , Serotonina/isolamento & purificação , Fator de Células-Tronco
9.
Biochemistry ; 29(13): 3349-54, 1990 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-2334696

RESUMO

This paper describes a procedure for the synthesis and application of a citalopram-derived affinity resin in purifying the 5HT-reuptake system from human blood platelets. A two-step scheme has been developed for partial purification, based on wheat germ agglutinin-lectin (WGA) affinity and citalopram affinity chromatographies. Upon solubilization of the carrier with 1% digitonin, a 50-70-fold increase in specific [3H]imipramine binding activity with a 70% recovery could be accomplished through WGA-lectin chromatography. The WGA pool was then subjected to affinity chromatography on citalopram-agarose. At least 90% of the binding capacity adsorbed to the column. Specific elution using 10 microM citalopram resulted in a 22% recovery of binding activity. A 10,000-fold overall purification was obtained by using this two-step procedure. Analysis of the fractions on SDS-PAGE after 125I labeling revealed specific elution of 78- and 55-kDa proteins concomitant with the appearance of [3H]imipramine binding activity. The pharmacological profile of the partially purified reuptake system correlated well with that derived from the crude membrane-bound reuptake system, suggesting a copurification of the 5HT binding activity and [3H]imipramine binding activity.


Assuntos
5-Hidroxitriptofano/isolamento & purificação , Plaquetas/análise , Citalopram , Fenômenos Químicos , Química , Cromatografia de Afinidade/métodos , Humanos , Solubilidade
10.
Antibiot Khimioter ; 33(1): 16-22, 1988 Jan.
Artigo em Russo | MEDLINE | ID: mdl-3259864

RESUMO

The process of asymmetric deacylation of an acetyl derivative of 5-benzyl hydroxytryptophan racemate in the presence of native microbial aminoacylase was studied. The effect of pH, temperature, concentration of the enzyme and substrate were investigated. Conditions for preparation and isolation of individual amino acids were defined by optimization of N-Ac-DU-5-BOT hydrolysis.


Assuntos
5-Hidroxitriptofano/análogos & derivados , 5-Hidroxitriptofano/isolamento & purificação , Amidoidrolases/farmacologia , Triptofano/análogos & derivados , Acilação , Fermentação , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Cinética , Análise de Regressão , Solubilidade , Estereoisomerismo , Temperatura , Triptofano/isolamento & purificação
11.
Acta Pharmacol Toxicol (Copenh) ; 46(3): 235-40, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6767340

RESUMO

Elution of GABA has been included in the method for separation of biogenic amines on small Dowex 50W columns described by Atack & Magnusson (1978). After extraction with perchloric acid and neutralization to pH 3.0, the sample is passed through the column. 5-HIAA might thereafter be eluted as described by Lindqvist (1971). After washes with water and 8 ml of a 0.025 M sodium citrate buffer pH 4.5, GABA is eluted in 3 ml of a 0.05 M sodium citrate buffer pH 5.3-5.4. The elution of tryptophane and the above mentioned amines can thereafter be performed. The recovery of GABA from the column is 100%. Silica thin-layer chromatography of the GABA eluate gives only one ninhydrine positive spot with a Rf value identical to GABA standard. When the GABA eluate from a whole brain and spinal cord is run on an automatic amino acid analyser, only one peak is detectable, eluted in the same position as GABA standard. Fluorescence analysis of the GABA eluate gives similar values if a( ninhydrine, b) acetylacetone plus formaldehyde or c) fluorescamine is used to form the flurophore. The GABA values are identical whether the samples reacted with ninhydrine are diluted with water or copper tartrate. The GABA concentrations found in some parts of the rat brain are of the same order of magnitude as reported by other authors.


Assuntos
Aminas Biogênicas/isolamento & purificação , Ácido gama-Aminobutírico/isolamento & purificação , 5-Hidroxitriptofano/isolamento & purificação , Animais , Química Encefálica , Cromatografia por Troca Iônica , Masculino , Norepinefrina/isolamento & purificação , Ratos , Extratos de Tecidos/análise , Triptofano/isolamento & purificação , beta-Alanina/isolamento & purificação , Ácido gama-Aminobutírico/análise
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