Evaluation of a Yeast Hydrolysate from a Novel Strain of Saccharomyces cerevisiae for Mycotoxin Mitigation using In Vitro and In Vivo Models

Mycotoxicoses in animals are caused by exposure to mycotoxin-contaminated feeds. Disease risk is managed using dietary adsorbing agents which reduce oral bioavailability. The objective of this work was to evaluate the efficacy of three selected yeast products as mycotoxin binders using in vitro and in vivo models. Their capacity to adsorb deoxynivalenol (DON), zearalenone (ZEA), and ochratoxin A (OTA) was evaluated using an in vitro model designed to simulate the pH conditions during gastric passage in a monogastric animal. Results showed that only one product, an enzymatic yeast hydrolysate (YHY) of a novel strain Saccharomyces cerevisiae, adsorbed about 45% of DON in solution. Next, we determined the effect of YHY on oral absorption of a DON, ZEA, and OTA mixture using a toxicokinetic model in swine. Toxicokinetic modeling of the plasma concentration-time profiles of DON, OTA, and zearalenone-glucuronide (ZEA-GlcA) showed that YHY tended to reduce the maximal plasma concentration of OTA by 17%. YHY did not reduce oral bioavailability of OTA, DON, and ZEA-GlcA. Within the context of this experiment, and despite some positive indications from both the in vitro and in vivo models employed, we conclude that the YHY prototype was not an effective agent for multiple mycotoxin adsorption.

PSXVI-1 Effect of dietary poppy seed meal supplementation on growth performance, nutrient digestibility, fecal microbiota, and blood profile in growing-finishing pigs

Yeast products are extensively used as additives in livestock feed to improve their growth performance and intestinal health. A total of 90 crossbred finishing pigs were allocated to one of three treatments according to their BW and sex (2 barrows and 2 gilts) with 6 replicates per treatment and 5 pigs per pen for eight weeks. The dietary treatments were CON -basal diet, CON + 0.05% yeast hydrolysate (YH), CON + 0.1% YH. The yeast hydrolysate supplement used in this study was commercially prepared in the name of CALMORIN. The active ingredients of YH were 40% of crude protein, 3.5% of nucleotides, 23% of β-glucans,4.9% glutamic acid, and 15% of mannan-oligosaccharides. Data were subjected to the statistical analysis as a complete randomized design using the GLM procedures of SAS and the pen was used as the experimental unit. Linear and quadratic polynomial contrasts were performed to determine the effects yeast in the diet with P < 0.05 indicating significance. Dietary inclusion of YH supplement linearly increased (P < 0.05) body weight and average daily gain of pigs at wk 4,8, and overall trail period (respectively). Moreover, apparent total digestibility of dry matter, nitrogen, and energy showed linear (P < 0.05) improvement in pigs fed graded level of YH supplementation. Also, the inclusion of YH supplementation linearly increased (P < 0.05) the fecal microbial lactobacillus population. Furthermore, during the end of the trial, pigs fed YH tended to linearly increase (P < 0.05) backfat thickness and lean meat percentage and linearly reduce drip loss (P > 0.05) from meat sample on day 3 and 5 of storage. In conclusion the growth performance, nutrient digestibility, lactobacillus count, and meat quality of finishing pigs were positively enhanced by yeast hydrolysate supplement in the diet.

Impact of yeast hydrolysate (Saccharomyces cerevisiae) supplementation on the growth performance, nutrient digestibility, fecal microflora, noxious gas emission, blood profile, and meat quality of finishing pigs

A total of 90 finishing pigs (52 ±1.46kg) were randomly assigned to 1 of 3 dietary treatments as: TRT1- (CON (basal diet)), TRT-2 (CON + 0.05% yeast hydrolysate (YH)), TRT3 – (CON + 0.1% YH) for 8 weeks trial. Each treatment had 6 replications and 5 (3 gilts and 2 barrow) pigs pen. In weeks 4 and 8, YH supplement linearly increased (P < 0.05) body weight. Moreover, average daily gain was also linearly increased (P < 0.05) with YH supplementation in week 4 and the overall trial period. At the end of the trial, apparent total tract digestibility of dry matter, nitrogen, and gross energy was linearly increased in pigs fed YH supplementation. In addition, fecal lactobacillus counts, IGF-1 concentration, and the lean meat percentage was linearly increased by YH supplementation. Also, YH supplementation elicited a linear reduction on drip loss during days 3, 5, and 7. In summary, dietary yeast hydrolysate supplement positively enhanced the growth performance, nutrient digestibility, lactobacillus count and reduce the drip loss traits of finishing pig. Thus, we infer that the application 0.1% S. cerevisiae yeast hydrolysate can enhance the growth efficiency of finishing pigs.

Characterization of Komagataeibacter Isolate Reveals New Prospects on Waste Stream Valorization for Bacterial Cellulose Production

Komagataeibacter spp. have been used for the bioconversion of industrial wastes and lignocellulosic hydrolysates to bacterial cellulose (BC). Recently studies have demonstrated the capacity of Komagataeibacter spp. in the biotransformation of inhibitors found in lignocellulosic hydrolysates, aromatic lignin-derived monomers (LDMs) and acetate. In general, detoxification and BC synthesis from lignocellulosic inhibitors requires a carbon flow from acetyl-coA towards tricarboxylic acid and gluconeogenesis, respectively. However, the related molecular aspects have not yet been identified in Komagataeibacter spp. In this study, we isolated a cellulose producing bacteria capable of synthesizing BC in a minimal medium containing crude glycerol, a by-product from biodiesel production process. The isolate, affiliated to Komagataeibacter genus, synthesized cellulose in minimal medium containing glucose (3.3&plusmn;0.3 g/L), pure glycerol (2.2&plusmn;0.1 g/L) and crude glycerol (2.1&plusmn;0.1 g/L). Genome assembly and annotation identified four copies of bacterial cellulose synthase operon and genes for redirecting the carbon from central metabolic pathway to gluconeogenesis. According to the genome annotations, a BC production route from acetyl-CoA, a central metabolic intermediate, was hypothesized and was validated using acetate. We identified that when K. rhaeticus ENS9b was grown in minimal medium supplemented with acetate, BC production was not observed. However, in presence of readily utilizable substrate, such as spent yeast hydrolysate, acetate supplementation improved BC synthesis.