Optimal concentration of organic solvents to be used in the broth microdilution method to determine the antimicrobial activity of natural products against Paenibacillus larvae

American Foulbrood (AFB) is a bacterial disease, caused by Paenibacillus larvae, that affects honeybees (Apis mellifera). Alternative strategies to control AFB are based on the treatment of the beehives with antimicrobial natural substances such as extracts, essential oils and/or pure compounds from plants, honey by-products, bacteria and moulds. The broth microdilution method is currently one of the most widely used methods to determine the minimum inhibitory concentration (MIC) of a substance. In this regard, the fact that most natural products, due to their lipophilic nature, must be dissolved in organic solvents or their aqueous mixtures is an issue of major concern because the organic solvent becomes part of the dilution in the incubation medium, and therefore, can interfere with bacterial viability depending on its nature and concentration. A systematic study was carried out to determine by the broth microdilution method the MIC and the maximum non inhibitory concentration (MNIC) against P. larvae of the most common organic solvents used to extract or dissolve natural products, i.e. ethanol, methanol, acetonitrile, n-butanol, dimethylsulfoxide, and acidified hydromethanolic solutions. From the MIC and MNIC for each organic solvent, recommended maximum concentrations in contact with P. larvae were established: DMSO 5% (v/v), acetonitrile 7.5% (v/v), ethanol 7.5% (v/v), methanol 12% (v/v), n-butanol 1% (v/v), and methanol-water-acetic acid (1.25:98.71:0.04, v/v/v).Fil: Cugnata, Noelia Melina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; ArgentinaFil: Guaspari, Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; ArgentinaFil: Pellegrini, María Celeste. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; ArgentinaFil: Fuselli, Sandra Rosa. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; ArgentinaFil: Alonso Salces, Rosa Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentin

Antimicrobial activity of phenolic extract of apple pomace against Paenibacillus larvae and its toxicity on Apis mellifera

Apis mellifera populations are exposed to different biotic and abiotic stressors that affect the bee survival. Paenibacillus larvae, the causative agent of American foulbrood, is one of the most important bacterial pathogens that affect bee health. In some countries, the use of antibiotics is the most common method for prevention and treatment of P. larvae infected colonies. However, this application can increase the risk of occurrence of resistant strains. An ecological alternative is the use of vegetal extracts containing bioactive compounds, such as polyphenols. The aim of this study is to check the antimicrobial activity of phenolic extracts of apple pomace, coming from the cider industry, against P. larvae strains by the broth micro dilution method. Besides, the toxicity of the phenolic extracts on A. mellifera was verified using the complete exposure method. All extracts contain from 715.31 to 11348.16 μg gal/g DW, determined by Folin-Ciocalteu showed antimicrobial activity against P. larvae genotype ERIC I, ranging from 23µg/mL to 150 µg/mL. Toxicity assays of apple pomace extracts on adult bees exhibited a maximum mortality of 18% after 48h. This promising alternative will be used in the future to evaluate its toxicity at field level.Fil: Giménez Martínez, Pablo Darian. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Maggi, Matías Daniel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Instituto de Investigaciones En Sanidad Produccion y Ambiente. - Comision de Investigaciones Cientificas de la Provincia de Buenos Aires. Instituto de Investigaciones En Sanidad Produccion y Ambiente.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Fuselli, Sandra Rosa. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentin

Vibrational Spectroscopy Coupled to a Multivariate Analysis Tiered Approach for Argentinean Honey Provenance Confirmation

In the present work, the provenance discrimination of Argentinian honeys was used as case study to compare the capabilities of three spectroscopic techniques as fast screening platforms for honey authentication purposes. Multifloral honeys were collected among three main honey-producing regions of Argentina over four harvesting seasons. Each sample was fingerprinted by FT-MIR, NIR and FT-Raman spectroscopy. The spectroscopic platforms were compared on the basis of the classification performance achieved under a supervised chemometric approach. Furthermore, low- mid- and high-level data fusion were attempted in order to enhance the classification results. Finally, the best-performing solution underwent to SIMCA modelling with the purpose of reproducing a food authentication scenario. All the developed classification models underwent to a “year-by-year” validation strategy, enabling a sound assessment of their long-term robustness and excluding any issue of model overfitting. Excellent classification scores were achieved by all the technologies and nearly perfect classification was provided by FT-MIR. All the data fusion strategies provided satisfying outcomes, with the mid- and high-level approaches outperforming the low-level data fusion. However, no significant advantage over the FT-MIR alone was obtained. SIMCA modelling of FT-MIR data produced highly sensitive and specific models and an overall prediction ability improvement was achieved when more harvesting seasons were used for the model calibration (86.7% sensitivity and 91.1% specificity). The results obtained in the present work suggested the major potential of FT-MIR for fingerprinting-based honey authentication and demonstrated that accuracy levels that may be commercially useful can be reached. On the other hand, the combination of multiple vibrational spectroscopic fingerprints represents a choice that should be carefully evaluated from a cost/benefit standpoint within the industrial context.Fil: Damiani, Tito. Universita Degli Studi Di Parma. Departamento de Alimentos y Drogas; ItaliaFil: Alonso Salces, Rosa Maria. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aubone, Inés. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Baeten, Vincent. Walloon Agricultural Research Centre; BélgicaFil: Arnould, Quentin. Walloon Agricultural Research Centre; BélgicaFil: Dall'Asta, Chiara. Universita Degli Studi Di Parma. Departamento de Alimentos y Drogas; ItaliaFil: Fuselli, Sandra Rosa. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Fernández Pierna, Juan Antonio. Walloon Agricultural Research Centre; Bélgic

Characterization of Argentinian Honeys Based on their Sugar Profiles and Quality Parameters

The honeys from the Argentinian provinces of Buenos Aires, La Rioja,Catamarca and Misiones were characterised by the sugar profile (fructose, glucose,sucrose, turanose, maltose and erlose) and the physicochemical parameters (freeacidity, pH, electrical conductivity (EC), colour and contents of moisture, ash,total soluble solids and hydroxymethylfurfural (HMF)) used for honey qualitycontrol. Authentic and traceable honey samples (n = 572) collected along fiveharvests were analysed using the official analytical methods. All honeys met thespecifications of the national and/or international standards for the evaluatedparameters, which denoted the blossom origin of most honeys, and confirmedtheir high quality, good maturity and freshness. The influence of the flora andthe pedoclimatic conditions of each phytogeographical region on the physicaland chemical properties of honey allowed its characterization. Thus, BuenosAires produced typical lighter honeys, and Misiones and Catamarca, darker ones.Buenos Aires honeys presented particular lower values of pH, EC, ash, HMF andmaltose, and higher concentrations of erlose. Misiones honeys exhibited highervalues of moisture, free acidity, EC and turanose amounts, and lower contentsof fructose, glucose and total soluble solids. La Rioja honeys showed higherpH and ºBrix values; and Catamarca honeys, higher sucrose contents. To theauthors? knowledge, the sugar profiles and several quality parameters of honeysfrom Misiones and Catamarca are here reported for the first time, as well as anyphysical and chemical data on La Rioja honeys.Fil: Poliero, Aimará Ayelen. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Aubone, Ines. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Amadei Enghelmayer, Marisa. No especifíca;Fil: Rosso, Valeria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Müller, Pablo Fernando. Instituto Nuestra Señora de Itatí. Profesorado en Ciencias Agrarias y Protección Ambiental; ArgentinaFil: Fuselli, Sandra Rosa. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Alonso Salces, Rosa Maria. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; Argentin

Physicochemical Characterization and Sugar Profile of Argentinian Honeys From the Phytogeographic Provinces Paranaense and Pampeana in Misiones

The characterization of honeys from the Biomes and vegetation units of the Phytogeographical Provinces (PP) located in the Province of Misiones (Argentina) was performed by analysis of sugar profile and physicochemical parameters (Free Acidity, pH, Electrical Conductivity (EC), colour and contents of moisture, ash, total soluble solids and hydroxymethylfurfural) used for quality control of honey. The honeys analysed were authentic and traceable, and met the specifications of the national and/or international standards for the evaluated parameters, denoting blossom origin and confirming high quality, maturity and freshness. The influence of biome and Vegetation Units (VU) on physical and chemical parameters of the studied honeys was defined regarding both flora and pedoclimatic conditions. Honeys from VU-27 presented significantly higher contents of fructose, ash and total soluble solids, pH and EC and lower moisture content than those from VU-3. To the authors’ best knowledge, sugar profiles, free acidity and contents of ash and total soluble solids in honeys from the different PPs, vegetation units and Biomes of Misiones are reported for the first time. This study contributes to the classification of honeys from Misiones, helping to increase added value and access new markets.Fil: Poliero, Aimará Ayelen. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Aubone, Ines. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Amadei Enghelmayer, Marisa. No especifíca;Fil: Rosso, Valeria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Müller, P. F.. No especifíca;Fil: Fuselli, Sandra Rosa. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Alonso Salces, Rosa Maria. Universidad Nacional de Mar del Plata. Instituto de Investigaciones En Produccion, Sanidad y Ambiente. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Mar del Plata. Instituto de Investigaciones En Produccion, Sanidad y Ambiente.; Argentin

Tempranillo grape extract in transfersomes: A nanoproduct with antioxidant activity

Polyphenols are gaining increasing interest due to their beneficial properties to human health. Grape pomace, the by-product of wine production, is a source of these bioactive compounds. An extract from Tempranillo grape pomace was obtained and characterized qualitatively and quantitatively. The major components found were anthocyanins, flavan-3-ols, and flavonols. To improve the bioavailability of these compounds, the extract was formulated in phospholipid vesicles, namely transfersomes. Spherical unilamellar vesicles around 100 nm each were obtained. The antioxidant activity of both the extract and the transfersomes was evaluated by using colorimetric assays (i.e., DPPH, FRAP, and Folin–Ciocalteu). The cells’ viability and the antioxidant activity were assessed in keratinocytes. The results showed that the extract and the transfersomes had no cytotoxic effects and exerted remarkable antioxidant activity, which was more evident in a vesicle formulation. These findings highlighted the potential of the Tempranillo grape pomace extract and the efficacy of the incorporation into phospholipid vesicles.Fil: Asensio Regalado, Carlos. Universidad del País Vasco; EspañaFil: Alonso Salces, Rosa Maria. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Gallo, Blanca. Universidad del País Vasco; EspañaFil: Berrueta, Luis A.. Universidad del País Vasco; EspañaFil: Era, Benedetta. Università Degli Studi Di Cagliari.; ItaliaFil: Pintus, Francesca. Università Degli Studi Di Cagliari.; ItaliaFil: Caddeo, Carla. Università Degli Studi Di Cagliari.; Itali

Geographical authentication of virgin olive oil by GC–MS sesquiterpene hydrocarbon fingerprint: Verifying EU and single country label-declaration

According to the last report from the European Union (EU) Food Fraud Network, olive oil tops the list of the most notified products. Current EU regulation states geographical origin as mandatory for virgin olive oils, even though an official analytical method is still lacking. Verifying the compliance of label-declared EU oils should be addressed with the highest priority level. Hence, the present work tackles this issue by developing a classification model (PLS-DA) based on the sesquiterpene hydrocarbon fingerprint of 400 samples obtained by HS-SPME-GC–MS to discriminate between EU and non-EU olive oils, obtaining an 89.6% of correct classification for the external validation (three iterations), with a sensitivity of 0.81 and a specificity of 0.95. Subsequently, multi-class discrimination models for EU and non-EU countries were developed and externally validated (with three different validation sets) with successful results (average of 92.2% of correct classification for EU and 96.0% for non-EU countries).Fil: Quintanilla Casas, Beatriz. Universidad de Barcelona; EspañaFil: Torres Cobos, Berta. Universidad de Barcelona; EspañaFil: Guardiola, Francesc. Universidad de Barcelona; EspañaFil: Servili, Maurizio. Università di Perugia; ItaliaFil: Alonso Salces, Rosa Maria. Universidad Nacional de Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Producción, Sanidad y Ambiente; ArgentinaFil: Valli, Enrico. Università di Bologna; ItaliaFil: Bendini, Alessandra. Università di Bologna; ItaliaFil: Gallina Toschi, Tullia. Università di Bologna; ItaliaFil: Vichi, Stefania. Universidad de Barcelona; EspañaFil: Tres, Alba. Universidad de Barcelona; Españ

1H–NMR fingerprinting and supervised pattern recognition to evaluate the stability of virgin olive oil during storage

Metabolomic fingerprinting of virgin olive oil (VOO) by 1H NMR spectroscopy was used to study its stability during storage simulating normal shelf life conditions during its commercialization. A representative set of VOOs covering the full range of possible chemical compositions were exposed to light (500 lux for 12 h/day) at 25 °C for 12 months or stored in the dark at 25 °C, 30 °C and 35 °C for 24 months. Multivariate data analysis of the 1H NMR spectra of the oil samples provided classification models to evaluate VOO freshness and to verify the light exposure of the VOO during storage, as well as regression models to determine VOO storage time and tentatively the best before date of a fresh VOO. These predictive models disclosed the chemical compounds responsible for the compositional changes in VOO due to hydrolytic and oxidative degradation taking place during its storage, and confirmed that light and increasing temperature enhance these processes. The presence of characteristic resonances of hydroperoxides (primary oxidation products) and the decrease of 1H signals assigned to phenolic compounds, mainly secoiridoid derivatives, and other minor compounds such as fatty acids, squalene and native (E)-2-hexenal present in fresh VOO revealed its oxidative degradation. Further, the emergence of low intensity 1H signals of saturated aldehydes meant that the secondary oxidation process has started at a low rate and yield. Moreover, the decrease of the 1H signals of triacylglycerides and sn-1,2-diacylglycerides, and the increase of sn-1,3-diacylglycerides indicated that hydrolytic degradation of VOO and diacylglyceride isomerisation was occurring. 1H NMR fingerprint of VOO together with pattern recognition techniques afford relevant information to assess the quality of VOOs taking into consideration legal, sensory and health-promoting aspects.Fil: Alonso Salces, Rosa Maria. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Gallo, Blanca. Universidad del País Vasco; EspañaFil: Collado, María Isabel. Universidad del País Vasco; EspañaFil: Sasía Arriba, Andrea. Universidad del País Vasco; EspañaFil: Viacava, Gabriela Elena. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: García González, Diego Luis. Universidad Pablo de Olavide; EspañaFil: Gallina Toschi, Tullia. Universidad de Bologna; ItaliaFil: Servili, Maurizio. Università di Perugia; ItaliaFil: Berrueta, Luis Ángel. Universidad del País Vasco; Españ

Valutazione della stabilità dell'ollio d'oliva vergine in conservazione mediante profilo 1H-NMR e chemiometria

La qualità dell'ollio vergine di oliva (VOO) è correlata alla sue proprietà sensoriali e nutrizionali, alla stabilità ossidativa e alla sua conservazione. L'ossidazione del VOO porta alla formazione di sostanze sgradevoli, alla degradazione dei suoi antiossidanti bioattivi e all'accumulo di composti di degradazione, causando la persita delle sua qualità sensoriali e salutari, del suo valore economico e dell'accettazione da parte dei consumatori. La resistenza del VOO all'ossidazione dipende dalla sua composizione chimica e dalla sua esposizione a fattori pro-ossidante come ossigeno, luce e temperatura. La stabilità del VOO durante la conservazione è stata studiata mediante un approccio metabolomico non mirato basato sull'impronta digitale 1H-NMR e sul riconoscimento del modello che simula le normali condizioni di conservazione durante la sua commercializzazione.Fil: Alonso Salces, Rosa Maria. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Gallo, Blanca. Universidad del País Vasco; EspañaFil: Poliero, Aimará Ayelen. Universidad Nacional de Mar del Plata; ArgentinaFil: Viacava, Gabriela Elena. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química. Grupo de Investigación en Ingeniería en Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: García González, Diego Luis. Instituto de la Grasa; España. Consejo Superior de Investigaciones Científicas; EspañaFil: Gallina Toschi, Tullia. Universidad de Bologna; ItaliaFil: Servili, Maurizio. Università di Perugia; ItaliaFil: Berrueta, Luis Angel. Universidad del País Vasco; Españ

FISCALIS Project Group - Analysis and Characterisation of Alcoholic Products (ACAP)

The purpose of the ACAP working group (composed of JRC, TAXUD and 11 Member States Custom Laboratories) was to provide scientific support for the resolution of the issue of divergent classifications of alcoholic beverages for excise duties, whether by providing objective criteria for classification, or providing sound scientific information for revision of legislation. In particular, there is a need for analytical methods allowing for the differentiation between "fermented" and "distilled" ("non-fermented") beverages and for the detection of ethanol addition. At present there is no commonly agreed solution of these problems which has resulted in the Customs Laboratories of the Member States developing their own particular approaches to deal with these issues. This can lead to divergent classification between Member States and consequent problems both for administrations and the trade. Two complementary pathways of investigation have been examined in this study: NMR fingerprinting and "classical analysis", both handled by multivariate data analysis. It is the findings of this study that it is likely to be extremely difficult or even impossible to create workable ¿general¿ models based on analytical methods. Unfortunately, the difficulties are the greatest precisely with those categories that are the most problematic for excise classification purposes. Even if an analytical model was eventually developed it is likely to need to be an extremely complex mechanism in order to take account of the broad range of beverages, and diverse chemical characteristics, of products that fall within the problem categories ("other fermented beverages" etc.). On the issue of 'added alcohol' the findings reinforce that is not plausible to ascertain the amounts by a scientific study of the finished product only. The case-to-case approach to classification applied by Member States remains therefore the only possible approach in the context of the current legislation.JRC.I.5-Physical and chemical exposure