21 research outputs found
An industry consensus study on an HPLC fluorescence method for the determination of (±)-catechin and (±)-epicatechin in cocoa and chocolate products
<p>Abstract</p> <p>Background</p> <p>This manuscript describes the results of an HPLC study for the determination of the flavan-3-ol monomers, (±)-catechin and (±)-epicatechin, in cocoa and plain dark and milk chocolate products. The study was performed under the auspices of the National Confectioners Association (NCA) and involved the analysis of a series of samples by laboratories of five member companies using a common method.</p> <p>Methodology</p> <p>The method reported in this paper uses reversed phase HPLC with fluorescence detection to analyze (±)-epicatechin and (±)-catechin extracted with an acidic solvent from defatted cocoa and chocolate. In addition to a variety of cocoa and chocolate products, the sample set included a blind duplicate used to assess method reproducibility. All data were subjected to statistical analysis with outliers eliminated from the data set.</p> <p>Results</p> <p>The percent coefficient of variation (%CV) of the sample set ranged from approximately 7 to 15%.</p> <p>Conclusions</p> <p>Further experimental details are described in the body of the manuscript and the results indicate the method is suitable for the determination of (±)-catechin and (±)-epicatechin in cocoa and chocolate products and represents the first collaborative study of this HPLC method for these compounds in these matrices.</p
A quantitative synthesis of the medicinal ethnobotany of the Malinké of Mali and the Asháninka of Peru, with a new theoretical framework
<p>Abstract</p> <p>Background</p> <p>Although ethnomedically and taxonomically guided searches for new medicinal plants can improve the percentage of plants found containing active compounds when compared to random sampling, ethnobotany has fulfilled little of its promise in the last few decades to deliver a bounty of new, laboratory-proven medicinal plants and compounds. It is quite difficult to test, isolate, and elucidate the structure and mechanism of compounds from the plethora of new medicinal plant uses described each year with limited laboratory time and resources and the high cost of clinical trials of new drug candidates.</p> <p>Methods</p> <p>A new quantitative theoretical framework of mathematical formulas called "relational efficacy" is proposed that should narrow down this search for new plant-derived medicines based on the hypothesis that closely related plants used to treat closely related diseases in distantly related cultures have a higher probability of being effective because they are more likely to be independent discoveries of similar plant compounds and disease mechanisms. A prerequisite to this hypothesis, the idea that empirical testing in traditional medicine will lead to choosing similar medicinal plants and therefore the medicinal flora of two distant cultures will prove to be more similar than their general flora, is tested using resampling statistics on cross-cultural field data of the plants used by the MalinkĂ© of Mali and the Asháninka of Peru to treat the diseases malaria, African sleeping sickness, Chagas' disease, leishmaniasis, diabetes, eczema, asthma, and uterine fibroids.</p> <p>Results</p> <p>In this case, the similarity of the medicinal floras is found to be significantly greater than the similarity of the general floras, but only when the diseases in question are grouped into the categories of parasitic and autoimmune diseases.</p> <p>Conclusion</p> <p>If the central theoretical framework of this hypothesis is shown to be true, it will allow the synthesis of medicinal plant information from around the world to pinpoint the species with the highest potential efficacy to take into the laboratory and analyze further, ultimately saving much field and laboratory time and resources.</p> <p><b>Spanish abstract</b></p> <p>Las bĂşsquedas que utilizan la etnomedicina y la taxonomĂa para descubrir nuevas plantas medicinales, pueden aumentar la probabilidad de Ă©xito de encontrar compuestos quĂmicos activos en plantas, en comparaciĂłn con las bĂşsquedas aleatorias. A pesar de lo anterior, en las Ăşltimas dĂ©cadas, la etnobotánica no ha cumplido con las expectativas de proveer numerosas plantas medicinales y quĂmicos nuevos una vez examinados en el laboratorio. Cada año se describen una plĂ©tora de plantas medicinales y sus usos, sin embargo las limitaciones de tiempo y recursos en los laboratorios, unidos al alto coste de los ensayos clĂnicos de las drogas potenciales, hacen muy difĂcil probar, aislar, y elucidar la estructura y el mecanismo de los compuestos de estas plantas. Se propone un nuevo marco teĂłrico cuantitativo cuyo fin es focalizar la bĂşsqueda de nueva plantas medicinales. Este marco teĂłrico está basado en la hipĂłtesis que las plantas cercanamente relacionadas, usadas para tratar enfermedades cercanamente relacionadas en culturas distantemente relacionadas, tienen una eficacia potencial más alta, debido a que es más probable que estos hallazgos sean descubrimientos independientes de compuestos quĂmicos similares. Parte de esta hipĂłtesis, que las escogencias racionales se hacen para elegir plantas medicinales similares y que la flora medicinal de dos culturas distantes es más similar que su flora general, se probĂł usando mĂ©todos estadĂsticos de remuestreo con datos de campo de la comunidad MalinkĂ© de MalĂ y de la Asháninka de PerĂş, y las enfermedades de paludismo, enfermedad africana del sueño, enfermedad de Chagas, leishmania, diabetes, eczema, asma, y fibromas uterinos. Se encontrĂł, en este caso, que la similitud de las floras medicinales es significativamente mayor a la similitud de las floras generales, solamente cuando las enfermedades analizadas se agruparon en las categorĂas de enfermedades parasitarias y enfermedades autoinmunes. Si se demostrara que las otras partes de esta hipĂłtesis son ciertas, se podrĂa sintetizar la informaciĂłn sobre plantas medicinales alrededor del mundo, para establecer asĂ las plantas potencialmente más eficaces para llevarlas al laboratorio y analizarlas más profundamente.</p> <p><b>French abstract</b></p> <p>Par rapport aux recherches menĂ©es de façon alĂ©atoire, les recherches effectuĂ©es par des critères ethnobotaniques et taxonomiques ont de meilleures chances Ă dĂ©couvrir de nouvelles plantes mĂ©dicinales Ă produit chimique actifs. Pendant les dernières dĂ©cennies pourtant, l'ethnobotanique a rĂ©alisĂ© peu de ces promesses Ă rĂ©vĂ©ler un grand nombre de plantes mĂ©dicinales et de nouveaux produits chimiques, testĂ©s au laboratoire. Avec les ressources limitĂ©es pour la recherche au laboratoire et le coĂ»t Ă©levĂ© des Ă©preuves cliniques pour trouver de nouveaux candidats aux mĂ©dicaments, il est difficile d'Ă©tudier, d'isoler et d'Ă©lucider la structure et le mĂ©canisme des produits chimiques de chacune des nombreuses plantes mĂ©dicinales (et les utilisations de ces plantes) dĂ©crites chaque annĂ©e. Nous proposons une nouvelle technique thĂ©orique et quantitative pour prĂ©ciser la recherche de nouvelles plantes mĂ©dicinales; elle est basĂ©e sur l'hypothèse que les plantes Ă©troitement apparentĂ©es, employĂ©es pour traiter les maladies Ă©troitement apparentĂ©es dans les cultures très Ă©loignĂ©es les unes des autres, ont une potentialitĂ© d'efficacitĂ© supĂ©rieure parce qu'elles reprĂ©sentent la dĂ©couverte indĂ©pendante des propriĂ©tĂ©s chimiques semblables des plantes. Une partie de cette hypothèse-qui dĂ©montre que la sĂ©lection des plantes mĂ©dicinales semblables est un choix rationnel et qu'il y a davantage de ressemblance dans la flore mĂ©dicinale de deux cultures Ă©loignĂ©es que dans leur flore gĂ©nĂ©rale-est examinĂ©e par un re-Ă©chantillonnage des donnĂ©es de recherches effectuĂ©es parmi les MalinkĂ© au Mali et les Asháninka au PĂ©rou, en particulier sur la malaria, la maladie africaine du sommeil, la maladie de Chagas, la leishmania, le diabète, l'eczĂ©ma, l'asthme et les fibromes utĂ©rins. Dans ces cas prĂ©cis, la similitude de la flore mĂ©dicinale s'avère sensiblement plus grande que la similitude de la flore gĂ©nĂ©rale, mais seulement quand les maladies en question sont regroupĂ©es ensemble comme maladies parasitaires et auto-immunitaires. Si cette hypothèse est prouvĂ©e, elle permettra la synthèse des informations recueillies sur les plantes mĂ©dicinales du monde entier pour en sĂ©lectionner de façon plus prĂ©cise celles qui sont les plus efficaces et qui mĂ©ritent analyse plus approfondie au laboratoire.</p> <p><b>Asháninka abstract</b></p> <p>Aayiantyarori iròpero aavintane, ontzimatye ancovacovatero ayotero ovaqueraripaye incashi iyoyetziri ashaninka, ayotzityaro aajatzi iyotane viracocha paitachari "quimica" ancantero aaca oshintsinka inchashipaye. Atziri yotacotzirori cametsa, ishtoriajacotzirori iyotane ashaninkapaye te iroñà rantero maaroni ocaratzi yamenacotaqueri laboratorioki. Aaviantyarori cametsa, ayotacotero aavintarontsiyetatsiri osamani antzimaventero ishtoriatacotaro, aajatzi osheki opinata ampinaventero aparopaye inchashi, acoviriqui ayotacotero, osaretsikipaye. Tzimatsi ovaquerari quenquishiriantsitatsiri ero opinata osheki ashitoriatacotero aparopaye inchashi, asampiyetatyrey pashinipaye atziri saicatsiri intaina puitarika inchasshi yavintari, ajatzirica oshiyaro ayotzi aaca, quemetachari atziri saikatsiri nampitsiki malinke aajatzi ishiyari ashaninka saicatsiri peruki, tzimatsi inchashi aajatzi yaavintari osheki okamètsatzi aririka anteri mantsiyarentsi icantaitziri ompetarentsi catsirentsi, pochokirentsi, patsarontsi(matatsi) ashipetate maaroni, ampochavathate, ancainikentsite, oncatsithakite tsinani. Aririka añaker aajatzi ahiyaro inchashi yaavintayetari pashinipaye atziri intainasatzi irdotake ahitoriatacoperoteri anĂ ashityard aavintarontsi ovamairiri shithanentsi, onĂ shitaavintarontsi tzicaacoventairi ero antane mantsiyarentsi. Omanperotatyarica iròperotzi avintarontsi, oshitovake laboratorioki aritaque iyoitanaquero maaroni quipatsiki iroperori avintarontsi.</p