RESUMEN
The global expansion in aquaculture production implies an emerging need of suitable and sustainable protein sources. Currently, the fish feed industry is dependent on high-quality protein sources of marine and plant origin. Yeast derived from processing of low-value and non-food lignocellulosic biomass is a potential sustainable source of protein in fish diets. Following enzymatic hydrolysis, the hexose and pentose sugars of lignocellulosic substrates and supplementary nutrients can be converted into protein-rich yeast biomass by fermentation. Studies have shown that yeasts such as Saccharomyces cerevisiae, Candida utilis and Kluyveromyces marxianus have favourable amino acid composition and excellent properties as protein sources in diets for fish, including carnivorous species such as Atlantic salmon and rainbow trout. Suitable downstream processing of the biomass to disrupt cell walls is required to secure high nutrient digestibility. A number of studies have shown various immunological and health benefits from feeding fish low levels of yeast and yeast-derived cell wall fractions. This review summarises current literature on the potential of yeast from lignocellulosic biomass as an alternative protein source for the aquaculture industry. It is concluded that further research and development within yeast production can be important to secure the future sustainability and economic viability of intensive aquaculture. © 2016 Society of Chemical Industry.
Asunto(s)
Alimentación Animal/análisis , Acuicultura , Peces/crecimiento & desarrollo , Abastecimiento de Alimentos , Proteínas Fúngicas/administración & dosificación , Salud Global , Levaduras/aislamiento & purificación , Aminoácidos/análisis , Alimentación Animal/economía , Animales , Acuicultura/economía , Acuicultura/tendencias , Biomasa , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/tendencias , Producción de Cultivos/economía , Digestión , Fermentación , Peces/metabolismo , Abastecimiento de Alimentos/economía , Agricultura Forestal/economía , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/química , Proteínas Fúngicas/economía , Humanos , Residuos Industriales/análisis , Residuos Industriales/economía , Lignina/química , Lignina/aislamiento & purificación , Lignina/metabolismo , Desnutrición/economía , Desnutrición/prevención & control , Ciclo del Nitrógeno , Levaduras/química , Levaduras/crecimiento & desarrollo , Levaduras/metabolismoRESUMEN
Test panels comprised of uncoated, copper coated and silicone coated 7/8'' (22 mm) mesh knitted nylon net were evaluated to compare their properties and the effectiveness to prevent biofouling. This paper describes test procedures that were developed to quantify the performance in terms of antifouling, cleanability, drag and cost. The copper treatment was the most effective at controlling fouling, however, the silicone treated nets were the easiest to clean. The drag forces on the net were a function of twine diameter, twine roughness and fouling. After immersion, the uncoated nets had the most drag followed by the silicone and copper treatments. The cost of applying silicone to nets is high; however, improved formulations may provide a non-toxic alternative to control fouling.