The necessary replacement of fish meal with other protein source in diets of commercially important fish has prompted the study of the effect of the inclusion of different vegetable proteins sources on growth performance and on the gastro-intestinal tract. Currently, soybean meal is the primary protein source as a fish meal replacement because of its low price and high availability. Likewise, it is been documented that the ingestion of soybean meal by several fish species, such as salmonids and carp, triggers a type of intestinal inflammation called enteritis. In this paper, we analyzed the effects of the ingestion of soybean meal and two of its components, soy protein and soy saponin, on zebrafish to establish the basis for using zebrafish larvae as a model for fish nutrition. We took advantage of the existence of different transgenic lines, which allowed us to perform in vivo analysis. Our results indicated that larvae that were feed with soybean meal developed a clear intestinal inflammation as early as two day after beginning the diet. Moreover, we determined that is not the soy protein present in the diet but the soy saponin that is primarily responsible for triggering the immune response. These findings support the use of zebrafish screening assays to identify novel ingredients that would to improved current fish diets or would formulate new ones.

Fungi are the primary infectious agents in plants causing significant economic losses in agroindustry. Traditionally, these pathogens have been treated with different synthetic fungicides such as hydroxianilides, anilinopyrimidines, and azoles, to name a few. However, the indiscriminate use of these chemicals has increased fungi resistance in plants. Natural products have been researched as a control, and an alternative to these synthetic fungicides since they are not harmful to health and contribute to the environment caring. This review describes plants extracts, essential oils, and active compounds or secondary metabolites as antifungal agents both, in vitro and in vivo. Active compounds have been recently described as the best candidates for the control of phytopathogenic fungi. When metabolized by plants, these compounds concentrations rely on the environmental conditions and pathogens incidence. However, one issue regarding the direct application of these preformed compounds in plants touch upon their low persistence in the environment, and their even lower bioavailability than synthetic fungicides. Hence the challenge is to develop useful formulations based on natural products to increase the compounds solubility facilitating thus their application in the field while maintaining their properties.

Fungi are the primary infectious agents in plants causing significant economic losses in agroindustry. Traditionally, these pathogens have been treated with different synthetic fungicides such as hydroxianilides, anilinopyrimidines, and azoles, to name a few. However, the indiscriminate use of these chemicals has increased fungi resistance in plants. Natural products have been researched as a control, and an alternative to these synthetic fungicides since they are not harmful to health and contribute to the environment caring. This review describes plants extracts, essential oils, and active compounds or secondary metabolites as antifungal agents both, in vitro and in vivo. Active compounds have been recently described as the best candidates for the control of phytopathogenic fungi. When metabolized by plants, these compounds concentrations rely on the environmental conditions and pathogens incidence. However, one issue regarding the direct application of these preformed compounds in plants touch upon their low persistence in the environment, and their even lower bioavailability than synthetic fungicides. Hence the challenge is to develop useful formulations based on natural products to increase the compounds solubility facilitating thus their application in the field while maintaining their properties.

Fungi are the primary infectious agents in plants causing significant economic losses in agroindustry. Traditionally, these pathogens have been treated with different synthetic fungicides such as hydroxianilides, anilinopyrimidines, and azoles, to name a few.However, the indiscriminate use of these chemicals has increased fungi resistance in plants. Natural products have been researched as a control, and an alternative to these synthetic fungicides since they are not harmful to health and contribute to the environment caring. This review describes plants extracts, essential oils, and active compounds or secondary metabolites as antifungal agents both, in vitro and in vivo. Active compounds have been recently described as the best candidates for the control of phytopathogenic fungi. When metabolized by plants, these compounds concentrations rely on the environmental conditions and pathogens incidence. However, one issue regarding the direct application of these preformed compounds in plants touch upon their low persistence in the environment, and their even lower bioavailability than synthetic fungicides. Hence the challenge is to develop useful formulations based on natural products to increase the compounds solubility facilitating thus their application in the field while maintaining their properties.PeerJ Preprints | https://doi.org/10.7287/peerj.preprints.26664v1 | CC BY 4.0 Open Access |

RESUMEN.El presente trabajo describe protocolo sobre la aplicación del desinfectante Buffodine® y un mix de antibacterianos para obtener alevines axénicos de trucha arcoíris (Oncorhynchus mykiss). Este protocolo permitió obtener y mantener alevines axénicos de trucha por un período de 26 días. Este período permite aplicaciones como ensayos con organismos gnotobióticos, una herramienta fundamental en los estudios para el entendimiento de la interacción bacteria-hospedero o parásito-hospedero. Palabras clave: Oncorhynchus mykiss, gnotobiótico, axénico, alevín, desinfectante, antibacteriano.Protocol for obtaining rainbow trout (Oncorhynchus mykiss) axenic fingerlings ABSTRACT. In this paper a protocol based on the application of Buffodine® disinfectant and a mix of antibacterials for obtaining rainbow trout (Oncorhynchus mykiss) axenic fingerlings is described. This allowed to obtain and maintain axenic trout fingerlings for a period of 26 days. This time allow to achieve a gnotobiotic organism, a fundamental tool in studies of the understanding bacteria-host interaction or host-parasite interaction. Keywords: Oncorhynchus mykiss, gnotobiotic, axenic, fingerling, disinfectant, antibacterial.Las investigaciones en organismos gnotobióticos (composición bacteriana conocida), buscan demostrar la influencia que pueden ejercer las bacterias de la microbiota sobre el hospedero en varios aspectos como inmunidad, nutrición, entre otros (Husebye, 1997;Rawls et al., 2004;Bates et al., 2006;Swaim et al., 2006;Pham et al., 2008;Nayak, 2010;Forberg et al., 2012;Situmorang et al., 2014). Previo al trabajo con organismos gnotobióticos, es necesario la obtención de un organismo axénico (libre de microorganismos); esta estrategia es útil para esclarecer el mecanismo de interacción que se genera entre la bacteria y el hospedero, a nivel celular y molecular, y así comprender una serie de procesos a nivel in vivo (Bates et al., 2006;Smith et al., 2007;Pham et al., 2008;Forberg et al., 2011;Situmorang et al., 2014).Uno de los primeros grupos de investigación en obtener peces axénicos fue el de Rawls et al. (2004), quienes observaron que la microbiota intestinal en monoasociación con el pez cebra (Danio rerio) axénico, influía en la regulación de la expresión significativa en __________________ Corresponding editor: Patricio Dantagnan aproximadamente 212 genes, relacionados con la estimulación de la proliferación epitelial, del metabolismo de nutrientes y la respuesta inmune innata a nivel intestinal, indicando que la interacción que se genere con el hospedero es dependiente del tipo de bacteria que lo colonice. Bates et al. (2006), observaron la importancia que ejerce la microbiota intestinal en el desarrollo y función del tracto digestivo. Estos autores determinaron en peces cebra (D. rerio) axénicos, que la ausencia de bacterias de la microbiota intestinal en el hospedero, disminuía la actividad de la enzima fosfatasa alcalina (enzima asociada con la detoxificación bacterial por la endotoxina lipopolisacárido, para controlar la inflam...