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Espectro químico de compuestos orgánicos volátiles de miel de pote de Erica Melipona favosa (Fabricius, 1798) de la Península de Paraguana, estado Falcón, Venezuela
No full textErica Melipona favosa (Fabricius, 1798) is a stingless bee living in the plains and coastal areas of Venezuela. Thirteen honey samples were collected by suction from sealed honey pots of a Melipona favosa meliponary from Guacurebo, Santa Ana piedmont of Paraguana Peninsula, Falcon state, Venezuela. The volatile organic compounds (VOCs) were analyzed using head space-solid phase micro extraction/gas chromatography/mass spectrometry HS-SPME/GC-MS and recorded areas. The abundance of 97 VOCs was organized according to the diversity of their chemical classes: 11 acids, 19 alcohols, 11 aldehydes, 30 esters, 5 ketones, 4 monoterpenes, 4 oxides, 2 sesquiterpenes, 2 others, and 9 unknown compounds. The most abundant VOC was acetic acid from 137.86 to 764.72. Surprisingly, lactic acid was not detected because it is not volatile. Ethyl acetate (3.60 to 63.60) and ethyl lactate (1.52 to 32.73) were the most abundant esters. Ethanol varied from 10.56 to 91.60, and the phenylethyl alcohol varied from 2.09 to 25.03. Half VOCs, 47/97 compounds were present in all pot-honey and 50/97 were variable not ubiquitous VOCs. Esterifications are important in the Melipona favosa honey volatilome, with 30/97 chemical compounds, and their functions a challenge to be explainedLa Erica Melipona favosa (Fabricius, 1798) es una abeja sin aguijón que habita en las llanuras y zonas costeras de Venezuela. Se recolectaron por succión 13 muestras de miel de potes sellados en un meliponario de Melipona favosa de Guacurebo, piedemonte del Cerro Santa Ana de la Península de Paraguaná, estado Falcón, Venezuela. Los compuestos orgánicos volátiles (COV) se analizaron mediante microextracción en fase sólida/cromatografía de gases/espectrometría de masas HS-espacio de cabeza. SPME/GC-MS y áreas registradas. La abundancia de 97 COV se organizó según la diversidad de sus clases químicas: 11 ácidos, 19 alcoholes, 11 aldehídos, 30 ésteres, 5 cetonas, 4 monoterpenos, 4 óxidos, 2 sesquiterpenos, 2 otros y 9 compuestos desconocidos. El COV más abundante fue el ácido acético de 137,86 a 764,72. Sorprendentemente, no se detectó ácido láctico porque no es volátil. El acetato de etilo (3,60 a 63,60) y el lactato de etilo (1,52 a 32,73) fueron los ésteres más abundantes. El etanol varió de 10,56 a 91,60 y el alcohol feniletílico varió de 2,09 a 25,03. La mitad de los COV, 47/97 compuestos estaban presentes en todas las mieles y 50/97 eran COVs variables no ubicuos. Las esterificaciones son importantes en el volatiloma de la miel de Melipona favosa, con 30/97 compuestos químicos, y sus funciones son un desafío por explica
El reservorio de ácido acético en el cerumen de potes de miel vacíos de Tetragonisca angustula se esterificó parcialmente con alcoholes formando los acetatos correspondientes
No full textSix plant resin-beeswax-based materials of the Venezuelan Angelita Tetragonisca angustula (Latreille, 1811) were collected from a nest in Merida: Entrance tube, involucrum of the brood, pillars by storage pots, empty honey pots, plant resin deposit, and indoor cover propolis. The abundance of volatile organic compounds (VOC) was studied by head space-solid phase microextraction (HS-SPME) and gas chromatography coupled to mass spectrometry (GC-MS). The cerumen of empty honey pots was a reservoir of acetic acid that esterified with alcohols into acetates. Methyl acetate was found only in the entrance tube, with isopropyl acetate, and 3-methyl-butyl acetate. A set of acetates characterized the empty honey pots: Ethyl acetate, isopropyl acetate, 3-methyl-butyl acetate, ethyl benzene acetate, and 2-phenetyl acetate. Ethyl acetate was the most abundant ester formed with the ethyl groups of the ethyl alcohol and the acetic acid in the cerumen of empty honey pots (32.63) and the plant resin deposit (17.21), and varied between 2.69 and 4.50 in other nest materials. Ethanol was the most abundant alcohol in the cerumen of empty honey pots (17.61) and the plant resin deposit (10.85) compared to lower values (2.47-6.43) in the involucrum, pillars, and propolis from the indoor cover. The highest abundance of acetic acid (108.79) possibly originated by acetic acid bacteria and alcohols originated by fermentation in the cerumen pots explain the formation of the acetates. The VOC profiles may have compounds of botanical, entomological, and microbial originSe recolectaron seis materiales a base de resina vegetal y cera de abejas de la Angelita Tetragonisca angustula (Latreille, 1811) de un nido en Mérida: tubo de entrada, involucro de la cría, pilares de los potes de almacenamiento, potes de miel vacíos, depósito de resina vegetal y propóleos interno de la tapa. La abundancia de compuestos orgánicos volátiles (COV) se estudió mediante micro extracción en fase sólidaespacio de cabeza (HS-SPME) y cromatografía de gases acoplada a espectrometría de masas (GC-MS). El cerumen de los potes de miel vacíos tiene una reserva de ácido acético que se esterifica con alcoholes formando acetatos. Se encontró acetato de metilo sólo en el tubo de entrada, junto con acetato de isopropilo y acetato de 3-metil-butilo. Un conjunto de acetatos caracterizó los potes de miel vacíos: acetato de etilo, acetato de isopropilo, acetato de 3-metil-butilo, acetato de etilbenceno y acetato de 2-fenetilo. El acetato de etilo fue el éster más abundante formado con los grupos etilo del alcohol etílico y el ácido acético en el cerumen de los potes de miel vacíos (32,63) y del depósito de resina vegetal (17,21), y varió entre 2,69 y 4,50 en otros materiales del nido. El etanol fue el alcohol más abundante en el cerumen de los potes de miel vacíos (17,61) y el depósito de resina vegetal (10,85) en comparación con valores más bajos (2,47-6,43) en el involucro, pilares y propóleos de la tapa interna. La mayor abundancia de ácido acético (108,79) posiblemente está originada por bacterias acéticas y los alcoholes originados por la fermentación en el cerumen de los potes, lo cual explica la formación de los acetatos. Los perfiles de COV pueden tener compuestos de origen botánico, entomológico y microbian
Perfil de volátiles por CG-EM de una miel de Erica Melipona favosa que huele a clavo de olor es producida en la Península de Paraguaná, estado Falcón, Venezuela
No full textMelipona favosa (Fabricius, 1798) was the first stingless bee described as Apis favosa by the Danish zoologist Johan Christian Fabricius, who proposed the basis for modern insect classification since the 18th century. The Melipona Illiger, 1806 genus was described later. A sample of Erica M. favosa honey with a distinctive clove smell was collected between Moruy and Guacurebo, in a meliponary at the foothills of Santa Ana hill, Falcon Municipality, Falcon state, Venezuela. Until El Niño in 1999 only peninsular Erica honey was produced before the arrival of Africanized bees. The abundance of volatile organic compounds (VOCs) of this honey was studied in triplicates by head space-solid phase microextraction (HS-SPME) and gas chromatography coupled to mass spectrometry (GCMS). A set of 63 VOCs were detected consisting of 14 acids, 13 alcohols, 6 aldehydes, 10 esters, 7 ketones, 2 monoterpenes, 4 oxides, and 7 unknown compounds. The most abundant were cis linalool oxide, trans linalool oxide, and acetic acid. The VOC that smells like clove was not identified. It is clearly not eugenol, but may be an unknown compound from another plant. It is ruled out that it is contamination, but here is a documented case study: In pasteurized orange juice, the formation of the clove-like odorant 5-vinylguaiacol originated after residues of the cleaning agent peracetic acid reacted with the natural orange flavonoid hesperidin after heatingMelipona favosa (Fabricius, 1798) fue la primera abeja sin aguijón descrita como Apis favosa por el zoólogo danés Johan Christian Fabricius, quien propuso las bases para la clasificación moderna de insectos desde el siglo XVIII. El género Melipona Illiger, 1806 se describió más tarde. Una muestra de miel de Erica Melipona favosa con un particular olor a clavo de olor fue recolectada entre Moruy y Guacurebo, en un meliponario al pie de la sierra de Santa Ana, Municipio Falcón, estado Falcón, Venezuela. Hasta El Niño de 1999 sólo se producía miel de Erica peninsular hasta la llegada de las abejas africanizadas. La abundancia de compuestos orgánicos volátiles (COVs) de esta miel se estudió por triplicado mediante espacio de cabezamicro extracción en fase sólida (EC-MEFS) y cromatografía de gases acoplada a espectrometría de masas (GC-EM). Se detectó un conjunto de 63 COVs conformado por 14 ácidos, 13 alcoholes, 6 aldehídos, 10 ésteres, 7 cetonas, 2 monoterpenos, 4 óxidos, y 7 compuestos desconocidos. Los más abundantes fueron el óxido de cis linalol, el óxido de trans linalol y el ácido acético. No se indentificó el COV que huele a clavo de olor. Claramente, no es eugenol, pero puede ser un compuesto desconocido de otra planta. Se descarta que sea contaminación, pero a continuación un caso documentado: En el jugo de naranja pasteurizado, la formación del 5-vinilguaiacol que huele a clavo de olor se originó cuando los residuos del agente limpiador ácido peracético reaccionaron con el flavonoide natural de la naranja hesperidin
First record of Zombrus bicolor (Enderlein) (Hymenoptera, Braconidae, Doryctinae) in\ua0Western\ua0Europe
No full textVolume: 219Start Page: 87End Page: 9
Volátiles del polen de abejas sin aguijón, bioactividad y descripción bibliométrica del polen de pote de abejas sin aguijón e inyección directa en lavor de alimentos
No full textPot-pollen has nutraceutical properties for bees and humans. This bibliometric review detected the first documented information on chemical composition of stingless bee pollen was in 2000, with further research on antibacterial, antioxidant, anticancer, antidiabetic, anti-inflammatory, leishmanicidal, and nutritional actions. Reviewed pot-pollen volatile richness was compared for Australian Austroplebeia australis (Friese, 1898) (27), Tetragonula carbonaria (Smith, 1854) (31), and Tetragonula hogkingsi (Cockerell, 1929) (28), and the Venezuelan Tetragonisca angustula (Latreille, 1811) (95). Bioactivity and olfactory attributes of the most abundant volatile organic compounds (VOCs) were reviewed Bibliometric analyses were planned for two unrelated topics in the literature for potential scientific advances. Most prolific authors, institutions, countries, funding sponsors, and sources engaged to disseminate original research and reviews on pot-pollen (2014 –2023) and direct injection food flavor (1976 –2023) were ranked by the Scopus database. Selected metrics and plots were visualized using Bibliometrix - R package. Scientific insights between an ancient fermented pot-pollen and powerful bioanalytical techniquesfor fermented products should attract interest of research teams for joint projects –including perhaps a book about Direct injection on pot-pollen flavor–El polen de pote tiene propiedades nutracéuticas para las abejas y los humanos. Esta revisión bibliométrica detectó el primer documento sobre composición química del polen de abeja sin aguijón en el año 2000, con acciones antibacterianas, antioxidantes, anticancerígenas, antidiabéticas, antiinflamatorias, leishmanicidas y nutricionales. La riqueza de volátiles del polen se comparó para las Austroplebeia australis (Friese, 1898) (27), Tetragonula carbonaria (Smith, 1854) (31) y Tetragonula hogkingsi (Cockerell, 1929) (28) australianas, y la Tetragonisca angustula (Latreille, 1811) venezolana (95). Se revisaron la bioactividad y los atributos olfativos de los compuestos orgánicos volátiles (COVs) más abundantes. Los análisis bibliométricos para dos temas no relacionados en la literatura representan un posible avance científico. La base de datos Scopus clasificó a los autores, instituciones, países, patrocinadores de financiación y fuentes más prolíficos comprometidos para difundir investigaciones y revisiones originales sobre el polen (2014 –2023) y el sabor de los alimentos por inyección directa (1976–2023). Las métricas y gráficos seleccionados se visualizaron utilizando el paquete Bibliometrix - R. La comprensión científica entre un antiguo polen fermentado y una poderosa técnica bioanalítica para productos fermentados debería atraer el interés de los equipos de investigación para proyectos conjuntos –incluyendo quizás un libro sobre la Inyección directa y para flavor de polen de pot
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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