ABSTRACT
ß-glucans are glucose polymers (polysaccharides) of high molecular weight naturally present in the cell wall of various living organisms such as bacteria, yeasts, fungus and plants (mainly cereals like barley and oat). ß-glucans are GRAS and are currently used as texturing agents by the food industry. Furthermore, scientific evidence suggest that, depending on their physicochemical structure and source, their intake would be associated with health promoting effect such as the decrease of plasma cholesterol and the improvement of the glycemic index of the ß-glucan-containing foodstuffs. Accordingly, a health claim related with the intake of cereal ß-glucans and plasma cholesterol improvement has been accepted by the FDA in U.S.A. and by the EFSA in the E.U. For this reason, ß-glucans are increasingly used in the world for the development of functional foods. However, the effect of yeast ß-glucans on immune system stimulation is still discussed.
Los ß-glucanos son polímeros de glucosa (polisacáridos) de elevado peso molecular que se encuentran en forma natural en la pared celular de diversos organismos vivos como bacterias, levaduras, hongos y plantas (cereales como avena y cebada). Los ß-glucanos son inocuos y actualmente son utilizados por las empresas de alimentos como agentes texturizantes. Además, antecedentes científicos sugieren que, dependiendo de su estructura fisicoquímica y de su origen, su consumo se asociaría a efectos beneficiosos para la salud del ser humano como la disminución de la concentración plasmática de colesterol total y la reducción del índice glicémico de los alimentos que lo incluyen. Un mensaje de salud sobre consumo de ß-glucanos de cereales y disminución del colesterol ha sido aceptado tanto por la FDA de EE.UU. como por la EFSA de la U.E. Por esta razón los ß-glucanos están siendo utilizados cada vez más para el desarrollo de alimentos funcionales en varios países del mundo. Sin embargo, el efecto de los ß-glucanos de levadura sobre la estimulación de la respuesta inmune aún está en discusión.
Subject(s)
Humans , Blood Glucose , Food Industry , Cholesterol , Health , beta-Glucans , Food , Impacts of Polution on HealthABSTRACT
The rainbow trout (Oncorhynchus mykiss) is one of most significant model in fish immunology, as well as a key species in European aquaculture. Two well-known Novirhabdoviruses, the viral haemorrhagic septicemia virus (VHSV) and the infectious hematopoietic necrosis virus (IHNV) cause serious damage in fish farms and represent a significant threat for aquaculture in a number of countries. A significant variability of resistance to these infections - intra- and inter-populations - has been described in rainbow trout. This genetic variability is not only relevant for the selection of fish naturally resistant to these viruses, but also for the dissection of the mechanisms of fish antiviral immunity. The methods used to analyze the genetic bases of the trout resistance to VHSV, and primary results are reported here from the identification of a major QTL to the impact of type I interferons.
