Yeast derived from lignocellulosic biomass as a sustainable feed resource for use in aquaculture

Abstract

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.

Marine macroalgae as sources of protein and bioactive compounds in feed for monogastric animals

“…[76][77][78] This implies that macroalgal carbohydrates wileyonlinelibrary.com/jsfa can be used as alternative carbon sources in fermentation processes to replace conventional carbohydrate sources like simple sugars. The chemical composition of the macroalgal biomass is complementary to lignocellulosic biomass, 79 which may facilitate yeast production by cofermentation in a biorefinery approach. The macroalgae can supply essential nutrients like nitrogen and minerals that are lacking in lignocellulosic biomass.…”

Multi‐strain yeast fraction product supplementation can alleviate weaning stress and improve performance and health of piglets raised under low sanitary conditions

“…Yeast supplementation favors the digestibility of crude protein . However, some animals may have difficulties digesting intact yeast cells, but the removal of the cell wall enhances the yeast extract's digestibility …”

“…31 However, some animals may have difficulties digesting intact yeast cells, but the removal of the cell wall enhances the yeast extract's digestibility. 32 A study by Shen et al 10 reported that supplementation of yeast culture in diets to weanling piglets improved total tract digestibility of DM, CP, and GE. Nochta et al 33 also reported that supplementation of a mannan-containing feed additive led to higher ileal digestibility of nutrients, particularly indispensable amino acids.…”

Candida utilis yeast as a functional protein source for Atlantic salmon (Salmo salar L.): Local intestinal tissue and plasma proteome responses

“…Microbial ingredients have proven to be high quality protein sources with the ability to mitigate the negative effects of plant-derived proteins [11]. Microbial ingredients such as yeast and bacteria contain bioactive compounds with immunemodulating properties that improve the changes caused by SBM [12-14].…”