Microencapsulación mediante secado por atomización a partir de un extracto de los cálices de Hibiscus sabdariffa L / Microencapsulation by spray drying from an extract of the calyces of Hibiscus sabdariffa L / Microencapsulação por secagem por pulverização a partir de um extrato dos cálices de Hibiscus sabdariffa L

Resumen La investigación tuvo como objetivo definir las mejores condiciones de extracción asistida por ultrasonido de los cálices de H. sabdariffa L. y la obtención de polvos microencapsulados, mediante secado por aspersión. Los extractos fueron analizados, considerando como variables: disolvente (agua y agua/etanol) y la relación temperatura/tiempo de extracción (25 °C/60 min y 60 °C/30 min). Para el secado se evaluaron las variables temperatura de entrada (150 °C; 190 °C) y la mezcla de encapsulantes goma arábiga (G) y maltodextrina (MD) (G40/ MD60; G60/MD40). Los parámetros utilizados para el análisis fueron: rendimiento, pH, °Bx, composición química (fenoles y antocianinas totales, CLAE-EM) y capacidad antioxidante (DPPH). La mejor condición para la extracción de polifenoles resultó ser con agua:etanol (80:20), a 60 °C y durante 30 min. Se identificó la presencia de ácidos fenólicos, glicósidos de flavonoles y las antocianinas (delfinidina-3-sambubiósido y cianidina-3-sambubiósido), como las señales de mayor intensidad. Con el secado por atomización a 150°Cy con G60/MD40, se logró el mayor contenido de fenoles totales y antocianinas, sin embargo, la capacidad antioxidante se favoreció a 150 °C y con G40/MD60. Las micropartículas obtenidas podrían valorarse como materia prima para la elaboración de fitofármacos o alimentos funcionales, considerando su fácil manipulación, posible estabilidad y su valor antioxidante.

Abstract The objective of the research was to define the best conditions for ultrasound-assisted extraction of H. sabdariffa L. calyces, and to obtain microencapsulated powders, by spray drying. The extracts were analyzed, considering as variables: extracting solvent (water and water/ethanol) and the temperature /extraction time ratio (25 °C/ 60 min and 60 °C/30 min). Inlet air temperature (150 °C; 190 °C) and the mixture of gum arabic (G) and maltodextrin (MD) as encapsulating agents (G40/MD60; G60/MD40) were the variables studied. The parameters used for the analysis were: yield, pH, °Bx, chemical composition (phenols and total anthocyanins, HPLC-MS), and antioxidant capacity (DPPH). The best polyphenols extraction conditions were water:ethanol (80:20), at 60 °C for 30 min. The presence of phenolic acids, flavonol glycosides, and anthocyanins (delphinidin-3-sambubioside and cyanidin-3-sambubioside) were identified as the signals of highest intensity. Inlet air temperature at 150 °C and G60/MD40 allowed the highest total phenols and anthocyanins content. However, the antioxidant capacity was better at 150 °C and G40/MD60. The microparticle obtained could be used as an ingredient for the preparation of phytopharmaceuticals or functional foods, considering their easy handling, and antioxidant capacity.

Resumo O objetivo da pesquisa foi definir as melhores condições para a extração assistida por ultrassom de H. sabdariffa L. calyces e obter pós microencapsulados, por meio de secagem por pulverização. Os extratos foram analisados considerando-se variáveis: menstruação (água e água/etanol) e a razão temperatura/tempo de extração (25 °C/60 min e 60°C/30 min). Para a secagem, os variais foram avaliados: temperatura de entrada (150 °C; 190 °C) e mistura dos encapsulantes goma arábica (G) e maltodextrina (MD) (G40/ MD60; G60/MD40). Os parâmetros utilizados para a análise foram: rendimento, pH, °Bx, composição química (fenóis e antocianinas totais, HPLC-MS) e capacidade antioxidante (DPPH). A melhor condição de extração acabou com a água: etanol (80:20), a 60 °C e por 30 min. A presença de ácidos fenólicos, flavonol glicosídeos e antocianinas (delfinidin-3-sambubiosídeo e cianidin-3-sambubiosídeo) foram identificados como sinais de maior intensidade. Com a secagem por pulverização a 150°Ce com G60/MD40, foi atingido o maior teor de fenóis e antocianinas totais, no entanto, a capacidade antioxidante foi favorecida a 150 °C e com G40/MD60. As microcápsulas obtidas podem ser utilizadas como matéria-prima na preparação de fitofarmacêuticos ou alimentos funcionais, considerando seu fácil manuseio, possível estabilidade e seu valor antioxidante.

Chemical profile and anti-leishmanial activity of three Ecuadorian propolis samples from Quito, Guayaquil and Cotacachi regions.

Three propolis samples were collected from different regions of Ecuador (Quito, Guayaquil and Cotacachi) and their methanolic extracts were prepared. Preliminary information supplied by TLC and NMR data, allowed us to define two main types of propolis: Cotacachi propoli sample (CPS), rich in flavonoids and Quito and Guayaquil samples (QPS and GPS) containing triterpenic alcohols and acetyl triterpenes as the main constituents. Two different approaches based on RP-HPLC preparative procedure and NMR structural determination (CPS) and GC-MS analysis (QPS and GPS) were successfully used for the chemical characterization of their major compounds. All three propolis extracts were able to inhibit Leishmania amazonensis growth but propolis sample rich in flavonoids was the most active (IC50=17.1±1.7µg/mL). In the literature this is the first study on propolis from Ecuador.

Estudio farmacognóstico preliminar de tallo y raíz de la especie Moringa Oleífera lam cosechada en Machala / Preliminary pharmacognostic study of the stem and root of the species Moringa Oleifera lam grown in Machala

Introducción: la composición química de las especies vegetales está sujeta a cambios, dependiendo, entre otros factores, de la localización geográfica. Moringa oleífera Lam., que crece en Machala, Ecuador, puede diferir de especies de otras regiones geográficas. Objetivo: realizar un estudio farmacognóstico preliminar del tallo y raíz (corteza y pulpa) de la planta M. oleífera cultivada en las áreas de la Unidad Académica de Ciencias Agropecuarias, de la Universidad Técnica de Machala. Métodos: se desarrolla el control de la calidad de la droga cruda según la metodología establecida por la Organización Mundial de la Salud, mediante determinación de la humedad residual, el porciento de cenizas y el porciento de sustancias solubles en el tallo y la raíz. Se cuantificaron algunos metales mediante espectrometría de emisión óptica con plasma acoplado inductivamente. El estudio químico preliminar se efectuó a través de ensayos de tamizaje fitoquímico y mediante cromatografía en capa delgada. Resultados: la humedad residual para ambos órganos y los valores de cenizas obtenidos para la raíz se encuentran dentro de los límites establecidos. Las cenizas totales para el tallo resultaron elevadas. La determinación de metales descartó la presencia de metales tóxicos en los órganos...(AU)

Introduction: The chemical composition of plant species is subject to changes which depend, among other factors, on their geographic location. The Moringa oleifera Lam. growing in Machala, Ecuador, may differ from species from other geographic regions. Objective: Conduct a preliminary pharmacognostic study of the stem and root (bark and pulp) of the plant M. oleifera grown in areas from the Agricultural Sciences Academic Unit of the Technical University of Machala. Methods: Quality control was performed of the crude drug following the methodology set up by the World Health Organization to determine residual humidity, percentage of ashes and percentage of soluble substances in the stem and the root. Several metals were quantified by inductively coupled plasma atomic emission spectroscopy. The preliminary chemical study was conducted by phytochemical screening testing and thin layer chromatography. Results: Both the residual humidity for both organs and the ash values obtained for the root are within the limits established. Total ashes for the stem were high. Metal determination discarded the presence of toxic metals in the organs studied. Values for soluble substances awarded a greater extraction capacity to water. Phytochemical screening pointed to the presence of triterpenes and steroids, reducing sugars, alkaloids, flavonoids, amino acids and saponins in root extracts. The stem was found to also contain catechins, mucilages and phenolic compounds, but not flavonoids. Thin layer chromatography pointed to the presence of alkaloids derived from phenyl methylamine. Conclusions: The study made it possible to set up crude drug quality parameters for the study species, make preliminary suggestions about similarities between the chemical composition of the plant analyzed and other plants of different geographic origin, and verify the absence of toxic metals in the organs studied(AU)

Estudio farmacognóstico preliminar de tallo y raíz de la especie Moringa Oleífera lam cosechada en Machala / Preliminary pharmacognostic study of the stem and root of the species Moringa Oleifera lam grown in Machala

Introducción: la composición química de las especies vegetales está sujeta a cambios, dependiendo, entre otros factores, de la localización geográfica. Moringa oleífera Lam., que crece en Machala, Ecuador, puede diferir de especies de otras regiones geográficas. Objetivo: realizar un estudio farmacognóstico preliminar del tallo y raíz (corteza y pulpa) de la planta M. oleífera cultivada en las áreas de la Unidad Académica de Ciencias Agropecuarias, de la Universidad Técnica de Machala. Métodos: se desarrolla el control de la calidad de la droga cruda según la metodología establecida por la Organización Mundial de la Salud, mediante determinación de la humedad residual, el porciento de cenizas y el porciento de sustancias solubles en el tallo y la raíz. Se cuantificaron algunos metales mediante espectrometría de emisión óptica con plasma acoplado inductivamente. El estudio químico preliminar se efectuó a través de ensayos de tamizaje fitoquímico y mediante cromatografía en capa delgada. Resultados: la humedad residual para ambos órganos y los valores de cenizas obtenidos para la raíz se encuentran dentro de los límites establecidos. Las cenizas totales para el tallo resultaron elevadas. La determinación de metales descartó la presencia de metales tóxicos en los órganos estudiados. Los valores de sustancias solubles indicaron mayor poder extractivo para el agua. La evaluación mediante tamizaje fitoquímico sugirió triterpenos y esteroides, azúcares reductores, alcaloides, flavonoides, aminoácidos y saponinas, en los extractos de la raíz. En el tallo se detectaron, además, catequinas, mucílagos y compuestos fenólicos, no así flavonoides. La cromatografía en capa delgada sugirió la existencia de alcaloides derivados de la fenilmetilamina. Conclusiones: el estudio permitió establecer parámetros de calidad de la droga cruda para la especie estudiada; sugerir, en principio, semejanzas en composición química de la planta analizada con otras de orígenes geográficos diferentes, y comprobar la ausencia de metales tóxicos en los órganos estudiados(AU)

Introduction: The chemical composition of plant species is subject to changes which depend, among other factors, on their geographic location. The Moringa oleifera Lam. growing in Machala, Ecuador, may differ from species from other geographic regions. Objective: Conduct a preliminary pharmacognostic study of the stem and root (bark and pulp) of the plant M. oleifera grown in areas from the Agricultural Sciences Academic Unit of the Technical University of Machala. Methods: Quality control was performed of the crude drug following the methodology set up by the World Health Organization to determine residual humidity, percentage of ashes and percentage of soluble substances in the stem and the root. Several metals were quantified by inductively coupled plasma atomic emission spectroscopy. The preliminary chemical study was conducted by phytochemical screening testing and thin layer chromatography. Results: Both the residual humidity for both organs and the ash values obtained for the root are within the limits established. Total ashes for the stem were high. Metal determination discarded the presence of toxic metals in the organs studied. Values for soluble substances awarded a greater extraction capacity to water. Phytochemical screening pointed to the presence of triterpenes and steroids, reducing sugars, alkaloids, flavonoids, amino acids and saponins in root extracts. The stem was found to also contain catechins, mucilages and phenolic compounds, but not flavonoids. Thin layer chromatography pointed to the presence of alkaloids derived from phenyl methylamine. Conclusions: The study made it possible to set up crude drug quality parameters for the study species, make preliminary suggestions about similarities between the chemical composition of the plant analyzed and other plants of different geographic origin, and verify the absence of toxic metals in the organs studied(AU)

In vitro antimicrobial assessment of Cuban propolis extracts

Propolis is a resinous mixture of different plant exudates collected by honeybees. Currently, propolis is widely used as a food supplement and in folk medicine. We have evaluated 20 Cuban propolis extracts of different chemical types, brown (BCP), red and yellow (YCP), with respect to their in vitro antibacterial, antifungal and antiprotozoal properties. The extracts inhibited the growth of Staphylococcus aureus and Trichophyton rubrum at low µg/mL concentrations, whereas they were not active against Escherichia coli and Candida albicans. The major activity of the extracts was found against the protozoa Leishmania, Trypanosoma and Plasmodium, although cytotoxicity against MRC-5 cells was also observed. The BCP-3, YCP-39 and YCP-60 extracts showed the highest activity against P. falciparum, with 50% of microbial growth (IC50) values of 0.2 µg/mL. A positive correlation between the biological activity and the chemical composition was observed for YCP extracts. The most promising antimicrobial activity corresponds to YCP subtype B, which contains acetyl triterpenes as the main constituents. The present in vitro study highlights the potential of propolis against protozoa, but further research is needed to increase selectivity towards the parasite. The observed chemical composition-activity relationship of propolis can contribute to the identification of the active principles and standardisation of this bee product.

In vitro antimicrobial assessment of Cuban propolis extracts.

Propolis is a resinous mixture of different plant exudates collected by honeybees. Currently, propolis is widely used as a food supplement and in folk medicine. We have evaluated 20 Cuban propolis extracts of different chemical types, brown (BCP), red and yellow (YCP), with respect to their in vitro antibacterial, antifungal and antiprotozoal properties. The extracts inhibited the growth of Staphylococcus aureus and Trichophyton rubrum at low µg/mL concentrations, whereas they were not active against Escherichia coli and Candida albicans. The major activity of the extracts was found against the protozoa Leishmania, Trypanosoma and Plasmodium, although cytotoxicity against MRC-5 cells was also observed. The BCP-3, YCP-39 and YCP-60 extracts showed the highest activity against P. falciparum, with 50% of microbial growth (IC50) values of 0.2 µg/mL. A positive correlation between the biological activity and the chemical composition was observed for YCP extracts. The most promising antimicrobial activity corresponds to YCP subtype B, which contains acetyl triterpenes as the main constituents. The present in vitro study highlights the potential of propolis against protozoa, but further research is needed to increase selectivity towards the parasite. The observed chemical composition-activity relationship of propolis can contribute to the identification of the active principles and standardisation of this bee product.

Activity of Cuban propolis extracts on Leishmania amazonensis and Trichomonas vaginalis.

In this paper we analyzed the antiprotozoal effects of eighteen Cuban propolis extracts (brown, red and yellow type) collected in different geographic areas, using Leishmania amazonensis (as a model of intracellular protozoa) and Trichomonas vaginalis (as a model of extracellular protozoa). All evaluated propolis extracts caused inhibitory effect on intracellular amastigotes of L. amazonensis. However, cytotoxicity on peritoneal macrophages from BALB/c mice was observed. Only five samples decreased the viability of T. vaginalis trophozoites at concentrations lower than 10 microg/mL. No correlation between the type of propolis and antiprotozoal activity was found. Cuban propolis extracts demonstrated activity against both intracellular and extracellular protozoa model, as well as the potentialities of propolis as a natural source to obtain new antiprotozoal agents.

Studies on the constituents of yellow Cuban propolis: GC-MS determination of triterpenoids and flavonoids.

In this study, on the basis of the information supplied by NMR and HPLC-PDA data, we reported a quali-quantitative GC-MS study of 19 yellow Cuban propolis (YCP) samples collected in different regions of Cuba. The profiles of YCP samples allowed us to define two main types of YCP directly related to their secondary metabolite classes: type A, rich in triterpenic alcohols and with the presence of polymethoxylated flavonoids as minor constituents, and type B, containing acetyl triterpenes as the main constituents. For the first time, triterpenoids belonging to oleanane, lupane, ursane, and lanostane skeletons were reported as major compounds in propolis. Also, the presence of polymethoxylated flavones or flavanones was found for the first time in propolis.

Chemical constituents of red Mexican propolis.

Chemical investigation of a red-type Mexican propolis sample has led to the isolation of three new compounds, 1-(3',4'-dihydroxy-2'-methoxyphenyl)-3-(phenyl)propane (1), (Z)-1-(2'-methoxy-4',5'-dihydroxyphenyl)-2-(3-phenyl)propene (2) and 3-hydroxy-5,6-dimethoxyflavan (3), together with seven known flavanones, isoflavans, and pterocarpans. Structural determination, was accomplished by spectroscopic analysis, particularly 2D NMR and ESI-MS/MS techniques. The present study appears to be the first report on the occurrence of isoflavonoids in Mexican propolis. In addition, the presence of compounds with a 1,3-diarylpropane and 1,3-diarylpropene carbon skeleton were found for the first time in propolis. Isolated compounds 1-10 indicated the possible relation between red Mexican propolis and the genus Dalbergia.

GC-MS determination of isoflavonoids in seven red Cuban propolis samples.

In the present study, the phenolic composition analysis of seven red varieties of propolis, collected in different regions of Cuba, was evaluated by gas chromatography/mass spectrometry (GC-MS). Seventeen compounds were identified in all samples by the interpretation of their mass spectra. This appears to be the first report on the GC-MS analysis of isoflavonoids in the propolis. The results confirmed the presence of the main isoflavonoids isolated previously and suggested the general structure for the other five isoflavonoids. Vestitol, 7-O-methylvestitol, and medicarpin were present in high amounts in all propolis samples analyzed. This result indicates that propolis samples rich in isoflavonoids are not exclusively found in Pinar del Rio province and proves that GC-MS technique is a useful and alternative tool for the chemical analysis of tropical red propolis.

Isoflavonoids isolated from Cuban propolis.

Chemical investigation of a red-type Cuban propolis sample has led to the isolation of 11 isoflavonoids (2 isoflavones, 3 isoflavans, and 6 pterocarpans), together with gallic acid, isoliquiritigenin, and (-)-liquiritigenin. Structural determination, including the absolute stereochemistry, was accomplished by spectroscopic analysis, particularly CD and 2D NMR techniques. The fragmentation behavior of pterocarpans was studied by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) using an ion-trap analyzer, and a generalized fragmentation pathway, useful in the identification and structural characterization of pterocarpans, is proposed. Isoflavonoids are reported for the first time from propolis samples.

Protective effect of gossypitrin on carbon tetrachloride-induced in vivo hepatotoxicity.

Carbon tetrachloride (CCl4) is a known environmental biohazard, which induces lipid peroxidation (LPO) and oxidative damage in rat liver. In this study, the hepatoprotective effect of Gossypitrin, a flavonoid extracted from Hibiscus elatus S.W, was investigated against the CCl4-induced in vivo hepatotoxicity. The levels of malondialdehyde (MDA) were assayed as an index of LPO and the levels of catalase (CAT) activity as a biomarker of oxidative damage. Leakage of aspartate aminotransferase (ALT) and lactate dehydrogenase (LDH), liver weight/body weight ratio as well as morphological parameters were used as signs of hepatotoxicity. CCl4 (1 ml/kg), intraperitoneally injected into rats, caused increased MDA production and CAT activity, and also a significant ALT and LDH leakage as compared to levels of these constituents in the control group. Changes in morphology, including steatosis, cells forming balloon cells and necrosis were evaluated in the hepatotoxin-induced damage. Treatment of rats with Gossypitrin (3.98, 5.97 and 8.95 mg/kg) 2 h before and 2 h after CCl4 injection, protected hepatocytes against cell injury induced by CCl4 and its efficacy as an antioxidant was similar to vitamin E (used as a reference antioxidant). These results are consistent with the conclusion that the toxicity of CCl4 is due to LPO and the generation of reactive oxygen species (ROS), and that Gossypitrin's protective effects relate to its direct radical scavenging ability and other antioxidative processes induced by its structure.

Estudio fitoquímico de la especie Hibiscus elatus SW / Phytochemical study of Hibiscus elatus SW

Se realizó un estudio fitoquímico preliminar de la especie Hibiscus elatus S.W. Se practicó un tamizaje fitoquímico sobre material seco y fresco, en el que se obtuvieron resultados positivos para mucílagos, sustancias reductoras, antocianinas, aminoácidos, taninos y flavonoides. Se determinó que las antocianinas se afectan durante el proceso de secado. Para la realización del estudio químico se maceró el material vegetal con 4 menstruos (fracciones A, B, C y D). A partir de las fracciones A y B se aisló el producto HE1, el cual se analizó por espectroscopia ultravioleta, infrarroja, de resonancia magnética nuclear protónica, de carbono 13, mediante uso de técnicas especiales y por espectrometría de masas, lo que permitió identificarlo como el flavonoide gossypitrina. La fracción C se sometió a un fraccionamiento según el método de absorción-desorción sobre silicagel, lo que permitió la detección de rutina y quercetina. Los flavonoides identificados se reportan por primera vez para la especie

Estudio fitoquímico de la especie Hibiscus elatus S.W / Phytochemical study of Hibiscus elatus S.W

Se realizó un estudio fitoquímico preliminar de la especie Hibiscus elatus S.W. Se practicó un tamizaje fitoquímico sobre material seco y fresco, en el que se obtuvieron resultados positivos para mucílagos, sustancias reductoras, antocianinas, aminoácidos, taninos y flavonoides. Se determinó que las antocianinas se afectan durante el proceso de secado. Para la realización del estudio químico se maceró el material vegetal con 4 menstruos (fracciones A, B, C y D). A partir de las fracciones A y B se aisló el producto HE1, el cual se analizó por espectroscopia ultravioleta, infrarroja, de resonancia magnética nuclear protónica, de carbono 13, mediante uso de técnicas especiales y por espectrometría de masas, lo que permitió identificarlo como el flavonoide gossypitrina. La fracción C se sometió a un fraccionamiento según el método de absorción-desorción sobre silicagel, lo que permitió la detección de rutina y quercetina. Los flavonoides identificados se reportan por primera vez para la especie (AU)