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We evaluated the insecticide activities of aqueous extracts of five species of plants from the Ecuadorian Amazon (Deguelia utilis (ACSm.) AMGAZEVEDO (Leguminosae: Papilionoideae), Xanthosoma purpuratum K. Krause (Alismatales: Araceae), Clibadium sp. (Asteracea: Asterales), Witheringia solanacea L'Hér (Solanales: Solanaceae), and Dieffenbachia costata H. Karst. ex Schott (Alismatales: Araceae)) plus Cymbopogon citratus Stapf. (Poales: Poaceae) under laboratory, open-field conditions in Plutella xylostella L. (diamondback moth), and semifield conditions in Brevicoryne brassicae L. Tap water was used as a negative control, and synthetic insecticides were used as positive controls. In a laboratory bioassay, aqueous extracts of D. utilis resulted in P. xylostella larval mortality. In contrast to chlorpyrifos, all botanicals were oviposition deterrents. All extracts except Clibadium sp. decreased leaf consumption by P. xylostella larvae. In semifield experiments, D. utilis, Clibadium sp., D. costata, and X. purpuratum initially controlled the population of B. brassicae, but 7 d after application, all botanicals except the D. utilis lost their ability to control the pest. In field experiments on broccoli crops in both dry and rainy seasons, the extracts did not control the abundance of P. xylostella, where as a mixture of two insecticides (chlorpyrifos + lambda cyhalothrin) did. These results show some incongruences from laboratory to semifield and field conditions, indicating that more studies, including the identification of the chemicals responsible for the biological activity, its stability, and the effects of chemotypes on insecticidal activity, are needed to understand the potential of these plant species as botanical insecticides.

Background: Allyl isothiocyanate is an excellent antimicrobial compound that has been applied in the development of active food packaging materials in the last years. However, the high volatility of this compound could prevent a lasting effect over time. In order to avoid this problem, cyclodextrin inclusion complexes have been proposed as an alternative, being beta-cyclodextrin (β-CD) as the main candidate. In addition, β-CD could act as a relative humidity-responsive nanoparticle. In this regard, the aim of this study was to develop inclusion complexes based on β-CD and AITC as relative humidity-responsive agents, which can be used in the design of active food packaging materials.Methods: Two different β-CD:AITC inclusion complexes (2:1 and 1:1 molar ratios) were obtained by the co-precipitation method. Entrapment efficiency was determined by gas chromatography, while inclusion complexes were characterized through thermal, structural, and physicochemical techniques. Antifungal capacity of inclusion complexes was determined in a headspace system. Furthermore, the AITC release from inclusion complexes to headspace at different percentages of relative humidity was evaluated by gas chromatography, and this behavior was related with molecular dynamic studies.Key Findings and Conclusions: The entrapment efficiency of inclusion complexes was over to 60%. Two coexisting structures were proposed for inclusion complexes through spectroscopic analyses and molecular dynamic simulation. The water sorption capacity of inclusion complexes depended on relative humidity, and they exhibited a strong fungicide activity against Botrytis cinerea. Furthermore, the AITC release to headspace occurred in three stages, which were related with changes in β-CD conformational structure by water sorption and the presence of the different coexisting structures. In addition, a strong influence of relative humidity on AITC release was evidenced. These findings demonstrate that β-CD:AITC inclusion complexes could be used as potential antifungal agents for the design of food packaging materials, whose activity would be able to respond to relative humidity changes.

Nowadays, polymeric materials are widely used in the development of food packages. However, as food products with a greater safety and longer durability are required, packaging research area has been focused on the production of functional materials able to reach such further protection. The incorporation of natural and synthetics active compounds into the polymeric materials by traditional techniques has been the main used strategy, surging thus the research area of active food packaging. Furthermore, the latest science advances provide promising technologies for developing packaging materials, such as the electrospinning. This technique has allowed obtaining ultrathin electrospun mats based on micro- and/or nanofibers that have been proposed as novel active materials able to be applied as wrapper films, sachets and bags during the food packaging. In this chapter, the description of electrospinning, the effect of their principal parameters during the development of active food packaging materials as well as their current applications on different foodstuffs are presented.

Eugenol (EUG) is the principal component of clove essential oil. It has demonstrated excellent antifungal properties against B. cinerea, one of the most important fungus in the fresh fruit decay. However, this substance is highly volatile, thermolabile and the direct contact with a food induce undesirable changes in the organoleptic properties. For this reason, the application of EUG represents a big challenger and its encapsulation through inclusion complexes formation with β-cyclodextrin (β-CD) is presented as a solution. In this way, the aim of this work was to develop, characterize and assess the antifungal capacity of inclusion complexes β-CD:EUG. For this, co-precipitation was used as method of inclusion complexes synthesis. The quantity of entrapped EUG was determined by gaseous chromatography. The inclusion complexes were characterized by thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR). Moreover, the antifungal activity was probed in a headspace system. Results showed that the EUG entrapped quantity was of 68,5 mg/g inclusion complexes. Furthermore, the characteristic peaks of EUG did not appear in inclusion complexes TGA thermogram and FTIR spectrum which confirm the effective compound encapsulation. Finally, inclusion complexes inhibited the growing of A. cinerea at 53% and avoided the fungal sporulation. These findings suggest that the β- CD:EUG inclusion complexes are suitable to use in the storage and transportation of fresh fruits to prevent their deterioration. Keywords: Botrytis cinerea, fresh fruits, headspace. Resumen El eugenol (EUG) es el principal componente del aceite esencial de clavo de olor. Éste ha destacado por su efectivo control de Botrytis cinerea, uno de los hongos más importantes que provoca la pudrición de frutas frescas. Sin embargo, esta sustancia es altamente volátil, termolábil y provoca cambios desagradables en las propiedades organolépticas del alimento si está en contacto directo con el mismo, por lo que su aplicación presenta un gran desafío. Ante esto, se propone su encapsulación a través de la formación de complejos de inclusión con β-ciclodextrina (β-CD). En este sentido, el objetivo de la presente investigación fue desarrollar, caracterizar y evaluar la capacidad antifúngica de complejos de inclusión β-CD:EUG. Éstos se sintetizaron mediante el método de co-precipitación, y la cantidad de EUG atrapada en la β-CD fue cuantificada por cromatografía de gases. Los complejos de inclusión se caracterizaron a través de análisis termogravimétrico (TGA) y espectroscospía infrarroja con transformada de Fourier (FTIR). Además, su actividad antifúngica se evaluó en un sistema de espacio de cabeza. Los resultados mostraron que la cantidad de EUG atrapada fue de 68,5 mg/g de complejo de inclusión. Además, en su termograma TGA y espectro FTIR no se observaron los picos característicos del EUG, confirmando la efectiva encapsulación del compuesto. Finalmente, los complejos de inclusión inhibieron el 53% del crecimiento de B. cinerea y evitaron su esporulación. Estos resultados permiten sugerir el uso de complejos de inclusión β-CD:EUG en el almacenamiento y transporte de frutas frescas para prevenir su deterioro. Palabras clave: Botrytis cinerea, frutas frescas, espacio de cabeza.

En los últimos años, el desarrollo de nanocompósitos poliméricos se plantea como una interesante alternativa para el diseño de nuevos materiales para el envasado activo de alimentos. A pesar de esto, existe constante preocupación relacionada a la migración de los componentes activos incorporados en el material ya que, un material de envasado destinado a entrar en contacto con un alimento debe presentar valores de migración bajo los límites establecidos en regulaciones internacionales. En este sentido, el objetivo del presente trabajo fue evaluar la migración del surfactante bromuro de cetilpiridinio (CPB) desde nanocompósitos activos de polietileno de baja densidad y montmorillonita modificada con CPB, hacia un simulante graso de alimentos (etanol 95 %). El seguimiento de la migración del componente se realizó a través de la medición de la conductividad eléctrica del simulante en contacto con los nanocompósitos. Se determinó que la presencia del 3,0 % de organoarcilla permite una mayor migración del CPB debido a la presencia del surfactante libre en la matriz y al hinchamiento de la organoarcilla superficial por hidratación. Además, se observó que la migración es prolongada en el tiempo y está por debajo de los límites permitidos por la legislación estadounidense, lo que permitiría la generación de materiales novedosos que podrían ser empleados en el diseño de envases activos de alimentos. In the last years, the development of polymeric nanocomposites is presented as an interesting alternative for the design of new materials for active food packaging. Despite this, there are concerns regarding the migration of the components incorporated in the material since a packaging material intended to come into contact with food must have migration values under the limits established in international regulations. In this sense, the aim in this work was to evaluate the migration of the surfactant cetylpyridinium bromide (CPB) from active nanocomposites of low density polyethylene and motmorillonite modified with CPB to a fatty food simulant (ethanol 95 %). The migration of the component was followed by fat simulant electrical conductivity measurements during the contact with the nanocomposites. It was determined that materials with 3,0 % of organoclay allowed a higher migration of CPB due to the presence of free surfactant in the matrix and swelling of the superficial organoclay. In addition, it was observed that the migration is prolonged in time and it is below the limits allowed by US legislation, which would enable the generation of novel materials that could be used in the design of active food packaging. Palabras clave: surfactante, conductividad eléctrica, polietileno de baja densidad, organoarcilla, envase activo de alimentos. Keywords: surfactant, electrical conductivity, low density polyethylene, organoclay, food active packaging.