Isolation and characterization of yeasts from fermented apple bagasse as additives for ruminant feeding

Abstract

Solid-state fermentation can be used to produce feeds for ruminants, which can provide an enriched population of yeasts to improve ruminal fermentation. Fermentation of apple bagasse was performed to obtain a yeast-rich product, with the objective of isolating, identifying, and characterizing yeast strains and testing their capability to enhance in vitro ruminal fermentation of fibrous feeds. Yeasts were isolated from apple bagasse fermented under in vitro conditions, using rumen liquor obtained from cannulated cows and alfalfa as a fibrous substrate. A total of 16 new yeast strains were isolated and identified by biochemical and molecular methods. The strains were designated Levazot, followed by the isolate number. Their fermentative capacity was assessed using an in vitro gas production method. Strain Levazot 15 (Candida norvegensis) showed the greatest increase in gas production (p < 0.05) compared with the yeast-free control and positively affected in vitro ruminal fermentation parameters of alfalfa and oat straw. Based on these results, it was concluded that the Levazot 15 yeast strain could be potentially used as an additive for ruminants consuming high-fiber diets. However, further studies of effects of these additives on rumen digestion, metabolism, and productive performance of ruminants are required.

Apple bagasse as a substrate for the propagation of Patagonian wine yeast biomass

“…Apple bagasse is an agricultural by‐product, rich in soluble carbohydrates that can be utilized for fermentative process promoting the growth of micro‐organisms (Castillo‐Castillo et al . ). However, there is no register in literature for the use of red apple bagasse as a substrate for yeast fermentation in batch or fed‐batch processes , except for studies on cashew apple bagasse applied for filamentous fungi solid state fermentation (Rodriguez et al .…”

“…In the last years, increased attention has been given to fruit industry residues for its abundant availability and cheap renewable feedstock for the production of valueadded compounds (Zhu et al 2015;Santos Felix et al 2018). Apple bagasse is an agricultural by-product, rich in soluble carbohydrates that can be utilized for fermentative process promoting the growth of micro-organisms (Castillo-Castillo et al 2016). However, there is no register in literature for the use of red apple bagasse as a substrate for yeast fermentation in batch or fed-batch processes, except for studies on cashew apple bagasse applied for filamentous fungi solid state fermentation (Rodriguez et al 2008), yeasts ethanol and biohydrogen production (Pacheco et al 2010;Silva et al 2018) or fermented apple bagasse for ruminant feeding (Castillo-Castillo et al 2016).…”

“…Apple bagasse is an agricultural by-product, rich in soluble carbohydrates that can be utilized for fermentative process promoting the growth of micro-organisms (Castillo-Castillo et al 2016). However, there is no register in literature for the use of red apple bagasse as a substrate for yeast fermentation in batch or fed-batch processes, except for studies on cashew apple bagasse applied for filamentous fungi solid state fermentation (Rodriguez et al 2008), yeasts ethanol and biohydrogen production (Pacheco et al 2010;Silva et al 2018) or fermented apple bagasse for ruminant feeding (Castillo-Castillo et al 2016). For this reason, our objective was to characterize a culture medium based on red apple bagasse and to test its use for the biomass production of indigenous yeasts of Comahue region belonging to the species S. cerevisiae and P. kudriavzevii, with proven aptitude for oenological use (del M onaco et al 2014a,b, 2016).…”

Composting of laying hen manure with the addition of a yeast probiotic

“…No Salmonella was noticeable by day 23 of fermentation in the three treatments. The elimination of Salmonella in the treatments with 7.5% and 15% of yeast after day 7 of fermentation could be related to the fact that yeast is a product rich in organic acids such as lactic acid and acetic acid (Castillo-Castillo et al 2016), which under certain conditions induce cell death (Ludovico et al 2001). The increase in these metabolites possibly inhibited the growth of this and other microorganisms present in the fermentation medium generating an antagonistic environment for undesirable putrefactive and pathogenic bacteria (Ludovico et al 2001).…”

“…Sheffield et al (2014) added three types of microorganisms to chicken manure (Saccharomyces cerevisiae; Rhodopseudomonas palustris and Lactobacillus casei) and found total reduction of Salmonella typhimurium at 9 days post-inoculation. The yeast (Candida norvegensis) containing the probiotic under study was isolated and identified by Castillo-Castillo et al (2016) which demonstrated a favourable effect as a non-Saccaromyces yeast on some fermentative parameters. Therefore, the objective of the present investigation was to evaluate the addition of the yeast probiotic at different concentrations (0%, 7.5% and 15%) and fermentation durations (0, 7 and 23 days), on hen manure silage to reduce its pathogenic microbiological load and thus make it more suitable for consumption by domestic animals.…”