LC-MS/MS analysis of neonicotinoid insecticides: Residue findings in chilean honeys / LC-MS/MS análises de inseticidas neonicotinoides: Resíduos encontrados em méis chilenos

ABSTRACT Neonicotinoids are a relatively new generation of insecticides that have been used for control of pests such as aphids, leafhoppers and whiteflies. This paper presents for the first time a determination of residues of four neonicotinoid insecticides (acetamiprid, thiamethoxam, thiacloprid and imidacloprid) in Chilean honey using QuEChERS extraction and UHPLC-MS/MS analysis. The limits of detection and quantification found for all analytes ranging from 0.34 to 1.43 μg kg-1 and from 0.30 to 4.76 μg kg-1, respectively. The extraction using QuEChERS method provided recoveries over 79% and the precision showed coefficient of variation lower than 20%. These data are in agreement with the international criteria that recommend general recovery limits of 70 - 120%. Of the 16 samples analyzed, in three honey samples neonicotinoids pesticides were detected. These three samples were collected from the same geographical area (Rengo). Fruit and grain production characterize the province of Rengo. The analysis of the botanical origin of these honeys showed the absence of pollen grains of crops and the majority presence of pollen grains of weeds such as Medicago sativa, Galega officinalis and Brassica rapa, which could be associated with crops. Although the residue levels found were low, the results also confirm the actual occurrence of a transfer of neonicotinoid insecticides from exposed honeybees into honey.

RESUMO Os neonicotinóides são uma geração relativamente nova de inseticidas que tem sido utilizado para o controle de pragas, como pulgões, cigarrinhas e moscas brancas. Este artigo apresenta pela primeira vez a determinação de resíduos de quatro inseticidas neonicotinóides (acetamiprida, tiametoxam, tiaclopride e imidaclopride) em méis chilenos empregando para extração o método QuEChERS seguido de UHPLC-MS/MS. Foram encontrados limites de detecção e quantificação aceitáveis para todos os analitos variando de 0,34 a 1,43 μg kg-1 e de 0,30 a 4,76 μg kg-1, respectivamente. A extração usando o método QuEChERS proporcionou uma recuperação maior que 79% e a precisão do método não excedeu um coeficiente de variação de 20%. Esses dados estão de acordo com os critérios internacionais que recomendam limites gerais de recuperação de 70 - 120%. Das 16 amostras de mel analisadas foram detectados pesticidas neonicotinoides em três delas. Essas três amostras foram coletadas na mesma área geográfica (Rengo), a qual se caracteriza pela produção de grãos e frutas. A análise da origem botânica desses méis mostrou a ausência de grãos de pólen de espécies cultivadas nesta zona, porém mostrou uma presença majoritária de grãos de pólen de ervas daninhas, como Medicago sativa, Galega officinalis e Brassica rapa, as quais podem estar associadas a estes cultivos. Embora os níveis de resíduos neonicotinoides encontrados neste estudo são baixos, os resultados confirmam a ocorrência atual de uma transferência destes inseticidas ao mel das de abelhas expostas.

Comparison of volatile compounds in Retanilla trinervia [Gillies & Hook] Hook & Arn honeys from central Chile / Comparación de compuestos volátiles en mieles de Retanilla trinervia[Gillies & Hook] Hook & Arn de Chile Central

The search for chemical markers for determining honey authenticity as a complementary tool for melissopalynological method is an important issue in the study of honeys from different botanical origins. The objective of this study was to determine the volatile compounds in tevo (Retanilla trinervia [Gillies & Hook] Hook & Arn [Fam. Rhamnaceae]) honey as one of the most relevant honeys from central Chile. For the identification and quantification of volatile compounds, Solid-Phase Microextraction and Gas Chromatography with Mass Spectrometry (SPME-GC-MS) was performed. A total of 28 out of 103 volatile compounds were found common to the five tevo honeys analyzed. Nevertheless, these compounds are common in unifloral honey of different floral sources from other countries. These results represent the first record in the identification of volatile compounds in tevo honey and would indicate that tevo honey does not present specific volatile compounds that allow its clear differentiation from other unifloral honey.

La búsqueda de marcadores químicos para determinar la autenticidad de la miel como una herramienta complementaria al análisis melisopalinológico es un tema importante en el estudio de las mieles de diferentes orígenes botánicos. El objetivo de este estudio fue determinar los compuestos volátiles en miel de tevo (Retanilla trinervia [Gillies & Hook] Hook & Arn [Fam. Rhamnaceae]), una de las mieles más relevantes de Chile Central. La identificación y cuantificación de compuestos volátiles se llevó a cabo mediante Microextracción en Fase Sólida y Cromatografía de Gases con Espectrometría de Masas (SPME-CG-MS). Un total de 28 de los 103 compuestos volátiles identificados en las cinco mieles de tevo analizadas se encontraron en común para ellas. Sin embargo, estos compuestos son comunes en la miel monofloral de diferentes fuentes florales de otros países. Estos resultados representan los primeros avances en la identificación de compuestos volátiles en la miel de tevo e indicarían que la miel de tevo no presenta compuestos volátiles específicos que permitan su clara diferenciación respecto a otras mieles monoflorales.

Actividad antioxidante y antimicrobiana de mieles monoflorales de plantas nativas chilenas / Antioxidant and antimicrobial activity of unifloral honeys of plants native to Chile

Chile has a great diversity of endemic and native species which gives floral origin to honey. Due the diversity of unifloral and multifloral honey previously identified it would be necessary to have information about the antioxidant content and biological activity. The objective of this study was to determine total phenols, antioxidant activity (DPPH and FRAP methods) and biological activity of unifloral honeys of native plants from Chile. For this purpose 59 beehoneys of different geographical origin were analyzed by melisopallinological method to determine the pollen present. Antimicrobial activity was tested against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pyogenes determining minimal bactericidal concentration (MBC). Results indicate that Chilean native honeys showed significant differences in their antioxidant as well as biological activity, which depends on the botanical and geographical origin, and it can be associated with polyphenol content.

Chile presenta una gran diversidad de especies vegetales endémicas y nativas que pueden dar origen a mieles producidas por Apis mellifera. En base a la diversidad de mieles poliflorales y monoflorales que han sido identificadas anteriormente en Chile, se propuso estudiar la actividad antioxidante y biológica para controlar el crecimiento de microorganismos patógenos. El objetivo de este estudio fue determinar el contenido de fenoles totales, actividad antioxidante (Métodos de FRAP y DPPH) y la actividad antibacteriana de mieles monoflorales de plantas nativas chilenas. Se utilizaron 59 mieles de diferente origen geográfico para determinar su origen botánico, mediante análisis melisopalinológico. La actividad antibactariana se evaluó contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus y Streptococcus pyogenes, determinando la concentración mínima bactericida (CMB). Los resultados indicaron que las mieles nativas de Chile muestran diferencias significativas tanto en la actividad antioxidante como en la actividad contra patógenos, la que depende del origen botánico y geográfico, pudiendo estar asociada al contenido de polifenoles.

Phenolic profiles of nectar and honey of Quillaja saponaria Mol. (Quillajaceae) as potential chemical markers

Quillaja saponaria Mol. (Quillajaceae) is one of the most important melliferous species in Chile, mainly as a source of monofloral honey. Honey made by A. mellifera presents biological activity against pathogens and antioxidant capacity associated with the presence of phenolic compounds deriving from the nectar, as a result of bee honey foraging. The aim of this study was to identify and quantify the phenolic compounds from the floral nectar of Q. saponaria and the honey made in apiaries in the central zone, and compare the composition of the chromatographic profiles of nectar and honey to known phenolic compounds. The results obtained by HPLC-DAD (high-performance liquid chromatography with diode-array detection) showed a similar profile of phenolic compounds, in which gallic acid, myricetin, rutin, quercetin and naringenin were identified. The phenolic compounds detected could be used as a reference for future studies for determining potential chemical markers of this honey, complementing the present identification of honeys by determining their botanical origin. The identification of bioindicators of the floral origins for honey of this species could provide added value to honey commercialization by certifying the botanical origin of their chemical features and biological attributes.

Chemical and botanical characterization of Chilean propolis and biological activity on cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus

Propolis is a non-toxic natural substance with multiple pharmacological properties including anticancer, antioxidant, fungicidal, antibacterial, antiviral, and anti-inflammatory among others. The aim of this study was to determine the chemical and botanical characterization of Chilean propolis samples and to evaluate their biological activity against the cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus. Twenty propolis samples were obtained from beekeeping producers from the central and southern regions of Chile. The botanical profile was determined by palynological analysis. Total phenolic contents were determined using colorimetric assays. Reverse phase HPLC and HPLC-MS were used to determine the chemical composition. The minimum inhibitory concentration (MIC) was determined on S. mutans and S. sobrinus. All propolis samples were dominated by structures from native plant species. The characterization by HPLC/MS, evidenced the presence of quercetin, myricetin, kaempferol, rutine, pinocembrin, coumaric acid, caffeic acid and caffeic acid phenethyl ester, that have already been described in these propolis with conventional HPLC. Although all propolis samples inhibited the mutans streptococci growth, it was observed a wide spectrum of action (MIC 0.90 to 8.22 µgmL-1). Given that results it becomes increasingly evident the need of standardization procedures, where we combine both the determination of botanical and the chemical characterization of the extracts. Research conducted to date, describes a promising effectiveness of propolis in the prevention of caries and other diseases of the oral cavity, making it necessary to develop studies to identify and understand the therapeutic targets or mechanisms of molecular action of the various compounds present on them.

Biological applications of honeys produced by Apis mellifera

Honey is a natural product with many attributes that are useful for humans. The consumption of honey is increasing because of its beneficial biological properties, including antioxidant and antibacterial activities. Even though honey is produced worldwide, many variants of this product have not been studied and their biological potential for alternative uses has not been evaluated. Because of its varied endemic native flora, Chile produces several types of honey. It is likely that these apian products have important biological properties inherited from specific floral sources, but it is absolutely necessary to conduct further chemical analyses to identify and characterize these biological attributes. Sadly, the potential antimicrobial and antitumor activities of Chilean honeys remain unproven at the present time. Further studies are needed to identify these attributes. In addition, the impact of human activities on the natural production of honey by bees should be considered. The use of honey as an environmental marker of pollution should also be considered, and care must be taken to diminish the effect of industry and human procedures on natural environments.

Honey is a natural product with many attributes useful for human beings. Nowadays, the consumption of honey is increasing due to its described biological properties such as antioxidant and antibacterial activities. However, honey is produced around the world and there still are many samples of this product that have not been studied or characterized in terms of their biological potential or alternative uses. Chile produces several kinds of honey, owing to the presence of a diverse endemic native flora. These bee products appear to have important biological properties inherited from specific floral sources, but further chemical analyses directed to determine the presence of biological attributes are absolutely necessary. Sadly, many potential effects against bacteria, fungi or antitumor or antiviral activities remain unknown at the present time. Further studies may reveal those attributes in the future. Another fact to be considered is the human activities that may affect the natural production of honey by bees. Despite the limited usefulness of honeys as environmental markers of pollution, they warn that industrial and human procedures should aim to decrease their impact on natural environments.

Comunicación acerca de la Red Internacional de Enfermería en Salud Infantil (RED ENSI) / Communication about the International Child Health Nursing (RED ENSI)

La Red de enfermeras de salud infantil en las Américas fue lanzada en 2006 sobre la base de anteriores colaboraciones de un grupo de enfermeras en Latinoamérica para estudiar las necesidades de fortalecimiento de los programas de enfermería de pediatría en la región. Esta red proporciona un modelo para promover la colaboración y comunicación entre las enfermeras de los diferentes países para mejorar la práctica de la enfermería pediátrica. Los objetivos iniciales de la Red fueron elaborados para compartir conocimientos y experiencias relacionadas con la enfermería de salud infantil en las Américas y promover la incorporación de las directrices relacionadas con la Estrategia de la Atención Integrada de las Enfermedades Prevalentes de la infancia (AIEPI) en los programas de enfermería en toda la región. Esta red de colaboración demuestra el poder de la enfermería que trabaja en forma concertada para aprovechar sus puntos fuertes y aumentar la capacidad de las enfermeras y los trabajadores de la salud para abordar las prioridades sanitarias mundiales relacionadas con la salud de los niños(AU)

The Network of Child Health Nurses in the Americas was launched in 2006 building on earlier collaboration of a group of nurses in Latin America to study the needs for strengthening pediatric nursing curricula in the region. This Network provides a model for promoting collaboration and communication between nurses of different countries to improve pediatric nursing practice. The initial goals of the Network are to share knowledge and experience related to child health nursing in the Americas and to promote incorporation of guidelines related to the Integrated Management of Childhood Illnesses (IMCI) in nursing curricula throughout the region. This collaborative network demonstrates the power of nursing working in a concerted way to build on its strengths and increase the capacity of nurses and health care workers to address global health priorities related to children's health care(AU)

El propóleos reduce la esteatosis hepática inducida por dieta en ratones / Propolis decrease diet-induced hepatic steatosis in mice

El hígado graso no alcohólico (HGNA), comprende un amplio espectro de lesiones, que van desde esteatosis hepática, hasta cirrosis y carcinoma hepatocelular, siendo sus principales factores de riesgo los desordenes asociados a síndrome metabólico (SM). El propóleos, sustancias resinosa elaborada por Apis mellifera para la protección de la colmena, ha demostrado un efecto hepatoprotector, así el objetivo de esta investigación fue evaluar el efecto de un propóleos chileno sobre el desarrollo de esteatosis hepática no alcohólica en ratones C57BL/6J sometidos a una dieta aterogénica tipo Paigen. Veintiocho ratones (C57BL/6J), divididos en: 1, dieta balanceada (CH); 2, dieta hipercolesterolémica (HC); 3, dieta HC + 10 mg/kg/día de propóleos (BP); 4, dieta HC + 40 mg/kg/día de propóleos (AP). Después de 16 semanas, se determinó la concentración de glucosa, colesterol total, triglicéridos y los niveles de alanina aminotransferasa (ALAT). El tejido hepático fue fijado en una solución de formalina tamponada al 10 por ciento para, posteriormente, ser incluido en paraplast y teñido con Hematoxilina-Eosina y fragmanetos congelados a -30C fijados en formalina teñidos con tinción Oil red O. No existieron diferencias en la concentración de glucosa ni triglicéridos, a diferencia del colesterol total, entre el grupo alimentado con dieta balanceada (CH) y los alimentados con la dieta aterogénica D12336 (HC, BP y AP). De la misma forma se observó que existen diferencias en los niveles de actividad de ALAT entre los grupos estudiados, destacando su reducción en los grupos suplementados con propóleos (BP y AP). De forma concordante, la histoarquitectura del grupo HC, mostró esteatosis simple y focos de infiltrado leucocitario en el lobulillo hepático, observándose una disminución gradual de las alteraciones en los grupos de BP y AP. En conclusión, el propóleos chileno estudiado disminuye la esteatosis hepática inducida por la dieta aterogénica tipo Paigen en ratones C57BL/6J, sin embargo, los mecanismos implicados en esta actividad hepatoprotectora tienen que ser identificados.

Nonalcoholic fatty liver disease (NAFLD) covers a wide spectrum of injuries ranging from simple steatosis to cirrhosis and hepatocellular carcinoma. Its main risk factors are disorders associated with metabolic syndrome (MS). Propolis, a resinous substance produced by Apis mellifera to protect is hive, has demonstrated a hepatoprotective effect. Thus, the aim of this study was to evaluate the effect of Chilean propolis on development of nonalcoholic hepatic steatosis in C57BL/6J mice exposed to Paigen atherogenic diet. Twenty eight mice C57BL/6J were divided four groups: 1, balanced diet (CH); 2, hypercholesterolemic diet (HD); 3, HD diet supplemented with 10 mg/kg/day of propolis (LP); 4, HD diet supplemented with 40 mg/kg/day of propolis (HP). After 16 weeks of treatment was determined glucose, total cholesterol and triglycerides concentrations and alanine aminotransferase (ALT) activity. The liver tissue was fixed in 10 percent buffered formalin solution, embedded in paraplast and stained with hematoxylin-eosin. No differences was detected in glucose and triglycerides concentrations, contrasting with total cholesterol levels between group fed with a balanced diet (CH) and feed with atherogenic diet D12336 (HD, LP and HP). In the same way, it was noted differences in ALT activity between groups, standing out the reduction in propolis supplemented groups (LP and HP). Likewise the histoarchitecture of HD group, showed simple steatosis, inflammatory cell infiltration and inflammatory foci in hepatic lobule. This characteristics show a gradual decrease in LP and HP groups. In conclusion, the Chilean propolis analyzed decreases hepatic steatosis induced by atherogenic diet in C57BL/6J mice. However, the involved mechanisms in this hepatoprotective activity must be identified.

Biological properties of the Chilean native moss Sphagnum magellanicum

An ethanol extract prepared from the gametophyte Chilean native moss Sphagnum magellanicum was dried out, weighed and dissolved in distilled water. This extract was then assayed for its antibacterial activity against the G(-) bacteria Azotobacter vinelandii, Erwinia carotovora subsp. carotovora, Enterobacter aerogenes, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Vibrio cholerae, and the G(+) bacteria Staphylococcus aureus subsp. aureus, and Streptococcus type b. The growth of the cultures of E. carotovora subsp. carotovora, and V. cholerae was inhibited at a concentration of 581mg/ml of extract, while the cultures of E. coli, S. typhi and Streptococcus type b were inhibited at a concentration of 1.16 mg/mL of extract. The concentration of phenolic compounds was 4.294 mg/mL; the presence of vanillic, chlorogenic, syringic, caffeic, gallic, 3-4 hydrozybenzoic, p-coumaric and salicylic acids was identified using RP- High Pressure Liquid Chromatography.