Reduced graphene oxide-based nanometal-composite containing copper and silver nanoparticles protect tomato and pepper against Xanthomonas euvesicatoria infection

Xanthomonas euvesicatoria (Xe) is of the genera Xanthomonas, which causes a bacterial spot disease that affects tomato and pepper plants, resulting in significant economic losses. Commonly used bactericides lead to pathogen resistance, environmental contamination and a current risk to human health. Herein, a nanocomposite consisting of Cu and Ag loaded onto reduced graphene oxide (rGO) was synthesized, characterized and tested. After confirmation of the antibacterial properties in vitro, nanocomposites at concentrations of 50 and 500 µg mL MINUS SIGN 1 were applied to protect tomato and pepper plants under controlled greenhouse conditions. The tomato and pepper plants indicated significantly lower disease severity when treated with the nanocomposite (15.6 and 16.7%, respectively) than when treated with the commercial copper-based bactericide Kocide(R) 2000. The nanocomposite was demonstrated as a high-efficiency biocide and has the potential for crop disease management with no phytotoxic effect.O

Wayusa: Biochemical Characteristics and Specific Cultural Aspects of its Use

Durante la investigación nos enfocamos en la determinación de la actividad antioxidante y el contenido total de polifenoles en la wayusa. La descripción de los métodos aplicados se presenta en este capítulo. La wayusa, desde el punto de vista ancestral, para el pueblo shuar, se caracteriza por ser una bebida energizante que es ingerida en horas de la madrugada y en ayunas, con el fi n de purifi car el organismo y proveerlo de energía durante todo el día. Esta tradición aún se mantiene pese a los cambios que ha vivido el territorio shuar, entre los que fi guran la expansión agrícola y ganadera. La wayusa es considerada una planta medicinal que según relatos de chamanes cuando se toma dicha infusión a primeras horas de la mañana, brinda protección contra los peligros de la selva, y a las mujeres les provee de fertilidad. Una parte del ritual consiste en contar los sueños de los participantes y poder descifrar su interpretación por medio de la bebida de la wayusa. Hoy en día, se puede apreciar cómo algunas comunidades shuar, tratan de reivindicar su tradición oral y su conocimiento ancestral por medio de la revalorización de wayusa que es parte de su identidad.During the research we focused on the determination of the antioxidant activity and the total content of polyphenols in wayusa. The description of the applied methods is presented in this chapter. Wayusa, from the ancestral point of view, for the Shuar people, is characterized by being an energizing drink that is ingested in the early morning and on an empty stomach, in order to purify the body and provide it with energy throughout the day. This tradition is still maintained despite the changes that the Shuar territory has undergone, among which are agricultural and livestock expansion. Wayusa is considered a medicinal plant that according to shamans' accounts, when ingested in the early morning hours, provides protection against the dangers of the jungle, and provides women with fertility. A part of wayusa ritual consists of counting the dreams of the participants and being able to decipher their interpretation by means of the drink. Currently, it is possible to see how some Shuar communities try to claim their oral tradition and ancestral knowledge through the revaluation of wayusa that is part of their identity.Published Versio

Wayusa: Biochemical Characteristics and Specific Cultural Aspects of its Use

Durante la investigación nos enfocamos en la determinación de la actividad antioxidante y el contenido total de polifenoles en la wayusa. La descripción de los métodos aplicados se presenta en este capítulo. La wayusa, desde el punto de vista ancestral, para el pueblo shuar, se caracteriza por ser una bebida energizante que es ingerida en horas de la madrugada y en ayunas, con el fi n de purifi car el organismo y proveerlo de energía durante todo el día. Esta tradición aún se mantiene pese a los cambios que ha vivido el territorio shuar, entre los que fi guran la expansión agrícola y ganadera. La wayusa es considerada una planta medicinal que según relatos de chamanes cuando se toma dicha infusión a primeras horas de la mañana, brinda protección contra los peligros de la selva, y a las mujeres les provee de fertilidad. Una parte del ritual consiste en contar los sueños de los participantes y poder descifrar su interpretación por medio de la bebida de la wayusa. Hoy en día, se puede apreciar cómo algunas comunidades shuar, tratan de reivindicar su tradición oral y su conocimiento ancestral por medio de la revalorización de wayusa que es parte de su identidad.During the research we focused on the determination of the antioxidant activity and the total content of polyphenols in wayusa. The description of the applied methods is presented in this chapter. Wayusa, from the ancestral point of view, for the Shuar people, is characterized by being an energizing drink that is ingested in the early morning and on an empty stomach, in order to purify the body and provide it with energy throughout the day. This tradition is still maintained despite the changes that the Shuar territory has undergone, among which are agricultural and livestock expansion. Wayusa is considered a medicinal plant that according to shamans' accounts, when ingested in the early morning hours, provides protection against the dangers of the jungle, and provides women with fertility. A part of wayusa ritual consists of counting the dreams of the participants and being able to decipher their interpretation by means of the drink. Currently, it is possible to see how some Shuar communities try to claim their oral tradition and ancestral knowledge through the revaluation of wayusa that is part of their identity.Published Versio

Smart bactericide based on reduced graphene oxide decorated with copper and zinc nanoparticles

Abstract Graphene oxide (GO) synthesised by modified Tour’s method was decorated with copper and zinc nanoparticles (NPs) and simultaneously reduced by sodium borohydride to obtain a nanocomposite of reduced GO with copper and zinc NPs (rGO–Cu–Zn). The nanocomposite rGO–Cu–Zn was characterised by transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The rGO–Cu–Zn was tested against Xanthomonas euvesicatoria (X. euvesicatoria), which attacks tomatoes and causes bacterial spots (BSs), and compared with the commercial product Champion 50 WG. Total bacterial growth inhibition was observed for the 1% rGO–Cu–Zn, whereas Champion 50 WG at the same concentration inhibited but did not eradicate all the bacterial colonies. To evaluate the negative effect of the rGO–Cu–Zn on the molecular level, the expression of the genes associated with the action of abiotic and biotic stress factors was analysed. Gene expression in the plants treated with 10% rGO–Cu–Zn did not exhibit a noticeable increase. Graphical Abstrac