Studies of the biological and therapeutic effects of argentine stingless bee propolis

Meliponids are native bees of the Americas, characterized by having no sting (ANSA). Some live in the Yunga forests of northern Argentina, a place rich in a diversity of this type of bees of which at least thirty-three species may be found. Propolis is a resinous substance that bees collect from plants exudates. Chemical composition and functional properties vary according to the flora of the place where the hives are. They have been valued by humans for their biological properties for centuries. This study is aimed at investigating the antinociceptive, antioxidant and anti-biofilm activities of propolis from the stingless bees Tetragonisca fiebrigi Schwarz and Scaptotrigona jujuyensis Schrottky found in Estación Experimental Agropecuaria Famaillá of INTA, Tucumán, Argentina. Analgesic activity of the extracts was estimated against acetic acid induced writhing, tail immersion method and formalin test. Antioxidant capacity was evaluated using DPPH free radical scavenging and β-carotene bleaching assays. Propolis anti biofilm activity was tested on Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATTC 6538P bacteria. Phytochemical constituents were obtained using standard chemical methods. The propolis alcoholic extracts of the studied species possess antinociceptive activity at both central and peripheral levels as demonstrated by the three algesia tests used. Both propolis extracts were effective antioxidants in DPPH and β-carotene linoleic acid model systems. S. jujuyensis propolis tested at all doses against S. aureus and P. aeruginosa presented a selective biofilm inhibition unrelated to bacterial growth inhibition, thus achieving a reduction in pathogenicity. The chemical studies revealed the presence of sterols, triterpenes, catechins, coumarins, flavonoids, phenols, tannins and anthocyanidins. Chemical composition observed in the T.fiebrigi and S. jujuyensis propolis, suggest that those responsible for the activity would be chemical compounds of a non-phenolic nature. Our data indicate that geopropolis is a natural source of bioactive substances with promising beneficial properties for human health. Isolation and identification of compounds responsible for the pharmacological activities displayed by propolis has started.Fil: Brodkiewicz, Ivana Yanina. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Farmacoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Marcinkevicius, Karenina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Reynoso Marcos. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Farmacoquímica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Salomon Virginia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Maldonado Luis. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Vera, Nancy Roxana. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Farmacoquímica; Argentin

Differentiation of argentine propolis from different species of bees and geographical origins by UV spectroscopy and chemometric analysis

Bees collect vegetal resins that they mix with their wax and mechanical impurities to elaborate propolis, whose chemical composition is complex and variable depending on botanical/geographical origin, type of bee, time of year when it was produced and function in the hive. The presence of compounds that absorb UV radiation, such as those of the phenolic type: acids, esters, flavonoids and chalcones, largely responsible for their antioxidant, antimicrobial and anti-inflammatory biological activity has been reported. The objective of the present work was to establish if it was possible to differentiate Argentine propolis using UV spectroscopy and chemometric analysis, in the following cases: a) Propolis elaborated by three different species of bees (Apis mellifera, Tetragonisca fiebrigi, Scaptotrigona jujuyensis) of the same geographical origin, and b) Propolis produced by a species of bee (Apis mellifera) of four different geographical origins. UV spectrograms were performed in the 190 to 420 nm range for all the samples followed by analysis of principal components, hierarchical clusters and linear discriminants. The results showed that Argentine propolis could be differentiated in the two cases studied, and that A.mellifera, T, fiebrigi and S. jujuyensis would not use the same plant species to produce them.Fil: Maldonado, Luis María. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Marcinkevicius, Karenina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Borelli, Romina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Gennari, Gerardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Salomón, Virginia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; ArgentinaFil: Vera, Nancy. Universidad Nacional de Tucuman. Facultad de Bioquímica, Química y Farmacia. Instituto de Farmacia. Cátedra de Farmacoquímica; ArgentinaFil: Borelli, Valeria Soledad. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Chaco-Formosa. Estación Experimental Agropecuaria Las Breñas; Argentin

Minimization of the mapping error using coordinate descent

Visualization harnesses the perceptual capabilities of humans to provide the visual insight into data. Structure preserving projection methods can be used for multidimensional data visualization. The goal of this paper is to suggest and examine the projection error minimization strategies that would allow getting a better and less distorted projection. The classic algorithm for Sammon’s projection and two new its modifications are examined. All the algorithms are oriented to minimize the projection error because even a slight reduction in the projection error changes the distribution of points on a plane essentially. The conclusions are made on the results of experiments on artificial and real data sets

Optofluidic lab-on-a-chip for rapid algae population screening

The rapid identification of algae species is not only of practical importance when monitoring unwanted adverse effects such as eutrophication, but also when assessing the water quality of watersheds. Here, we demonstrate a lab-on-a-chip that functions as a compact robust tool for the fast screening, real-time monitoring, and initial classification of algae. The water-algae sample, flowing in a microfluidic channel, is side-illuminated by an integrated subsurface waveguide. The waveguide is curved to improve the device sensitivity. The changes in the transmitted optical signal are monitored using a quadrant-cell photo-detector. The signal-wavelets from the different quadrants are used to qualitatively distinguish different families of algae. The channel and waveguide are fabricated out of a monolithic fused-silica substrate using a femtosecond laser-writing process combined with chemical etching. This proof-of-concept device paves the way for more elaborate femtosecond laser-based optofluidic micro-instruments incorporating waveguide networks designed for the real-time field analysis of cells and microorganisms

Inhibited carrier transfer in ensembles of isolated quantum dots

We report significant differences in the temperature-dependent and time-resolved photoluminescence (PL) from low and high surface density InxGa1-xAs/GaAs quantum dots (QDs). QD's in high densities are found to exhibit an Arrhenius dependence of the PL intensity, while low-density (isolated) QD's display more complex temperature-dependent behavior. The PL temperature dependence of high density QD samples is attributed to carrier thermal emission and recapture into neighboring QD's. Conversely, in low density QD samples, thermal transfer of carriers between neighboring QD's plays no significant role in the PL temperature dependence. The efficiency of carrier transfer into isolated dots is found to be limited by the rate of carrier transport in the InxGa1-xAs wetting layer. These interpretations are consistent with time-resolved PL measurements of carrier transfer times in low and high density QD's. [S0163-1829(99)04748-7]

Generalized solitary waves in nonintegrable KdV equations

The generalization of the classical Korteweg-de-Vries (KdV) solitary wave solution is presented in this paper. The amplitude and the propagation speed of generalized KdV solitary waves vary in time. Generating partial differential equations and conditions of existence of the generalized KdV solitary waves are derived using the inverse balancing method. Computational experiments illustrate the variety of new solitary solutions and their generating equations

Physicochemical and melissopalynological profiles of Citrus limon honey from Tucumán-Argentina. Hesperidin as a suitable marker of floral origin

Geographical Indications (GI) are tools used to add value, protect and recognize the differentiated quality of a product as a consequence of environmental and territorial influence. The objective of this work was to determine physicochemical, melissopalynological and sugar profiles plus chemical markers of Citrus limon monofloral honey produced in Tucumán-Argentina, to the development of the GI “Lemon blossom honey from Tucumán”. Samples harvested between August and October 2016, 2017 and 2018 were analyzed. It was established that in addition to Citrus limon, the most frequent pollen species was Salix type. This honey is very light in color (≤ 30 mm Pfund), slightly acidic (≤ 20 meq.kg-1), with moisture values from 15 to 19 g/100g, low diastatic activity (≤ 27 Gothe units), HMF (≤ 3.0 mg.kg-1) and electrical conductivity (≤ 0.32 mS.cm-1). Color inversely correlates with the amount of Citrus limon pollen. The sugar profile showed a higher fructose content than glucose, sucrose and maltose, and intermediate tendency towards crystallization. Hesperidin was easily detected and quantified in all samples. The content of methyl anthranilate was much lower than the international reference for citrus honeys and also, was not detected in some samples. Hence, should be a complementary indicator and hesperidin could be used instead as a chemical marker of genuineness.Las Indicaciones Geográficas (IG) son herramientas utilizadas para agregar valor y para proteger y reconocer la calidad diferencial de un producto como consecuencia de la influencia ambiental y territorial. El objetivo de este trabajo consistió en determinar los perfiles físicoquímicos, melisopalinológicos y de azúcares, además de marcadores químicos de mieles monoflorales de Citrus limon producidas en Tucumán-Argentina, para el desarrollo de la IG “Miel de azahar de limón de Tucumán”. Se analizaron muestras cosechadas entre agosto y octubre de 2016, 2017 y 2018. Se estableció que además de Citrus limon, la especie de polen más frecuente fue la del tipo Salix. Esta miel es de color muy claro (≤ 30 mm Pfund), ligeramente ácida (≤ 20 meq.kg-1), con valores de humedad de 15 a 19 g/100 g, baja actividad diastásica (≤ 27 unidades Gothe), HMF (≤ 3,0 mg.kg-1) y conductividad eléctrica (≤ 0,32 mS.cm-1). El color se correlaciona inversamente con la cantidad de polen de Citrus limon. El perfil de azúcares mostró mayor contenido de fructosa que glucosa, sacarosa y maltosa, y una tendencia intermedia a la cristalización. La hesperidina se detectó y cuantificó fácilmente en todas las muestras. El contenido de metil antranilato fue mucho menor que la referencia internacional para mieles de cítricos y además, no se detectó en algunas muestras. Por lo tanto, debería ser un indicador complementario y la hesperidina podría usarse en su lugar como un marcador químico de autenticidad.EEA FamailláFil: Maldonado, Luis Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Marcinkevicius, Karenina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Marcinkevicius, Karenina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Salomon, Virginia María. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Sanchez, A.C. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas; ArgentinaFil: Sanchez, A.C. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecorregiones Andinas; Argentina.Fil: Alvarez, Alejandro Raul. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Lupo, Liliana Concepción. Universidad Nacional de Jujuy. Instituto de Ecorregiones Andinas; ArgentinaFil: Lupo, Liliana Concepción. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecorregiones Andinas; Argentina.Fil: Bedascarrasbure, Enrique Luciano. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro de Investigación de Agroindustria. Programa Nacional Apícola (PROAPI); Argentin

STUDIES OF THE BIOLOGICAL AND THERAPEUTIC EFFECTS OF ARGENTINE STINGLESS BEE PROPOLIS

Meliponids are native bees of the Americas, characterized by having no sting (ANSA). Some live in the Yunga forests of northern Argentina, a place rich in a diversity of this type of bees of which at least thirty-three species may be found. Propolis is a resinous substance that bees collect from plants exudates. Chemical composition and functional properties vary according to the flora of the place where the hives are. They have been valued by humans for their biological properties for centuries. This study is aimed at investigating the antinociceptive, antioxidant and anti-biofilm activities of propolis from the stingless bees Tetragonisca fiebrigi Schwarz and Scaptotrigona jujuyensis Schrottky found in Estación Experimental Agropecuaria Famaillá of INTA, Tucumán, Argentina. Analgesic activity of the extracts was estimated against acetic acid induced writhing, tail immersion method and formalin test. Antioxidant capacity was evaluated using DPPH free radical scavenging and β-carotene bleaching assays. Propolis anti biofilm activity was tested on Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATTC 6538P bacteria. Phytochemical constituents were obtained using standard chemical methods. The propolis alcoholic extracts of the studied species possess antinociceptive activity at both central and peripheral levels as demonstrated by the three algesia tests used. Both propolis extracts were effective antioxidants in DPPH and β-carotene linoleic acid model systems. S. jujuyensis propolis tested at all doses against S. aureus and P. aeruginosa presented a selective biofilm inhibition unrelated to bacterial growth inhibition, thus achieving a reduction in pathogenicity. The chemical studies revealed the presence of sterols, triterpenes, catechins, coumarins, flavonoids, phenols, tannins and anthocyanidins. Chemical composition observed in the T.fiebrigi and S. jujuyensis propolis, suggest that those responsible for the activity would be chemical compounds of a non-phenolic nature. Our data indicate that geopropolis is a natural source of bioactive substances with promising beneficial properties for human health. Isolation and identification of compounds responsible for the pharmacological activities displayed by propolis has started. &nbsp