Co-production of amino acid-rich xylooligosaccharide and single-cell protein from paper mulberry by autohydrolysis and fermentation technologies

Background Autohydrolysis is an extensively investigated pretreatment method due to its environmental friendliness. During autohydrolysis, most xylan from hemicellulose can be converted into xylooligosaccharides (XOS), and cellulose in the autohydrolyzed residues can be transformed into glucose after enzymatic hydrolysis. Both of these are value-added biochemicals in the biorefining process. In this work, paper mulberry (PM), which contains abundant protein, was utilized as a raw material to coproduce XOS and single-cell protein (SCP) through autohydrolysis and fermentation technologies. Results The results showed that 8.3 g of XOS and 1.8 g of amino acids could be recovered in the autohydrolysate (based on 100 g raw material) after autohydrolysis (170 °C, 1 h). Moreover, 5.7 g of low-DP XOS along with 1.8 g of amino acids could be further obtained from the autohydrolysate after hydrolysis with endo-β-1-4-xylanase. In addition, 20.1 g of fermentable monosaccharides was recovered after hydrolyzing the autohydrolyzed PM with cellulase, which can be used to produce 4.8 g of SCP after fermentation with Candida utilis. Conclusion As a valuable application of PM, a novel process is proposed to coproduce amino acid-rich XOS and SCP through autohydrolysis. The carbohydrate of PM is effectively converted to high value-added products.

The Effects of Fermentation of Low or High Tannin Fava Bean-Based Diets on Glucose Response, Cardiovascular Function, and Fecal Bile Acid Excretion during a 28-Day Feeding Period in Dogs: Comparison with Commercial Diets with Normal vs. High Protein

We have shown that feeding dogs fava bean (FB)-based diets for 7 days is safe and FB flour fermentation with Candida utilis has the potential to decrease FB anti-nutritional factors. In the present study, the effects of 28-day feeding of 4 different FB-based test dog foods containing moderate protein (~27% dry matter (DM)) were compared with two commercial diets with normal protein (NP, grain-containing, ~31% DM protein) or high protein (HP, grain-free, ~41% DM protein). Health parameters were investigated in beagles fed the NP or HP diets or using a randomized, crossover, 2 × 2 Latin square design of the FB diets: unfermented high-tannin (UF-HT), fermented high-tannin (FM-HT), unfermented low-tannin (UF-LT), and fermented low-tannin (FM-LT). The results showed that fermentation increased glucose tolerance, increased red blood cell numbers and increased systolic blood pressure, but decreased flow-mediated vasodilation. Taken together, the overall effect of fermentation appears to be beneficial and improved FB nutritional value. Most interesting, even though the HP diet was grain-free, the diet did contain added taurine, and no adverse effects on cardiac function were observed, while glucose tolerance was impaired compared to NP-fed dogs. In summary, this study did not find evidence of adverse cardiac effects of pulses in ‘grain-free’ diets, at least not in the relatively resistant beagle breed over a 28-day period. More importantly, fermentation with C. utilis shows promise to enhance health benefits of pulses such as FB in dog food.

Candida utilis: a rare cause of septicemia in children

Candida utilis is an emerging fungal pathogen in blood. The main aim of this study was to describe the prevalence, methods of speciation and antifungal susceptibility of Candida utilis at a tertiary care centre. Methods. This was a retrospective study carried out at a tertiary care centre in South India. Over a period of 1 year, three Candida utilis were isolated from blood culture identified by MALDI–TOF MS Version 3.2 and were confirmed by ITS sequencing. Susceptibility testing was carried out by micro broth dilution. Results. All three patients had a common risk factor of prolonged ICU stay but the source of infection could not be identified. Candida utilis isolates were identified by MALDI–TOF and confirmed by ITS sequencing. They were pansusceptible to all tested antifungal drugs. Among these, two patients who were treated in hospital had good clinical outcome and response to antifungal drugs. A third patient was lost to follow up. Conclusion. Candida utilis was predominantly seen between 0–3 month olds. Conventional methods of speciation were unable to identify C. utilis to species level. Rapid identification was done by MALDI–TOF MS and confirmed by sequencing. Rapid identification leads to prompt treatment and favours a good clinical outcome.

PSIII-4 Nutritional evaluation of yeast biomass from candida utilis as a protein source in cat diets

Yeast products have found much favor within companion animal nutrition. A recently developed proprietary process has introduced an enhanced yeast biomass from Candida utilis (merchandised as SylPro®) into the animal food marketplace. Candida utilis has been shown to be a valuable protein in canine, swine and aquaculture diets; however, no previous research has evaluated its use in feline diets. Therefore, the current objective was to determine the nutrient digestibility of diets containing SylPro® yeast biomass (SYL) as the primary protein source relative to soybean meal (SOY), pea protein concentrate (PEA), and chicken meal (CKN) fed to cats. Apparent total tract digestibility (ATTD) of diets were estimated using Titanium dioxide as an indigestible marker. The DM ATTD for SYL was lower (P < 0.0001) than CKN (86.39 vs. 87.43%, respectively) but similar to both SOY (85.66%) and PEA (86.54%). The OM ATTD of SYL, SOY, and PEA were not different (P < 0.0001) and were each lower than CKN (average of 89.60 vs. 91.16%, respectively). The CP ATTD for SYL (89.9%) was not different from the other three treatments (P = 0.0200). Crude fat ATTD of SYL was lower (92.52%; P < 0.0001) than all treatments with PEA being greatest (94.82%) and CKN and SOY intermediate (average of 93.84%). The SYL and CKN had higher TDF ATTD (average of 66.20%; P < 0.0001) relative to PEA and SOY (average of 49.79%). The GE ATTD of SYL was lower than CKN (90.18 vs. 90.97%, respectively; P = 0.0154) but similar to both SOY (90.18%) and PEA (90.30%). In conclusion, all diets were highly digestible but CKN preformed the best. The SYL diet was similar to CKN for ATTD of CP and TDF. The SYL diet was also similar to both SOY and PEA for ATTD of DM, OM, CP and GE.

Effects of Dietary Yucca Schidigera Extract and Oral Candida utilis on Growth Performance and Intestinal Health of Weaned Piglets

Weaning piglets experienced the transformation from breast milk to solid feed and present the proliferation of pathogens, the presence of diarrhea, poor growth performance and even death. Plant extracts and probiotics have certain potential in improving animal growth performance, antioxidant capacity and immune function. The purpose of this study was to explore the effects of dietary yucca schidigera extract (YSE) and oral Candida utilis (CU) on growth performance and intestinal health weaned piglets. According to a 2 × 2 factorial design with the main factors being CU (orally administered 1 mL of 0.85% saline with or without CU; fed basal diet with or without 120 mg/kg YSE), forty 28 d healthy weaned piglets were randomly allocated into four groups of 10 barrows each: (1) piglets fed basal diet and orally administered 1 mL of 0.85% saline (CON); (2) piglets fed basal diet and orally administered 1 mL 1 × 109 cfu/mL C. utilis in 0.85% saline (CU); (3) piglets fed the basal diet containing YSE (120 mg/kg) and orally administered 1 mL of 0.85% saline (YSE); (4) Piglets fed the basal diet containing 120 mg/kg YSE and 1 mL 1 × 109 cfu/mL C. utilis in 0.85% saline (YSE+CU). This study lasted 28 days and evaluated the effects of dietary YSE and oral CU on growth performance, immunity, antioxidant function, ileal morphology, and intestinal microflora in weaned piglets. Dietary YSE increased ADG, the spleen and lymph node indexes, serum GLU, BUN, T-SOD, T-AOC, CAT concentrations, ileal villus height and villus height/crypt depth, jejunal occludin, and β-definsin-2 concentrations and ileal occludin concentration in weaned piglets (P < 0.05); decreased the diarrhea rate and mortality, rectal pH and urine pH, the BUN and MDA concentrations, crypt depth (P < 0.05); improved the diversity of cecal microflora. Orally CU increased ADG, and ADFI, the T-SOD, T-AOC, and CAT activity, ileal villus height, villus height/crypt depth, jejunum occludin, and β-definsin-2 concentrations (P < 0.05); reduced the diarrhea rate and mortality, urine pH, the BUN and MDA concentrations, crypt depth (P < 0.05); improved the diversity of cecal microflora. Dietary YSE and orally CU increased the T-SOD, T-AOC, and CAT activity, villus height/crypt depth, jejunal occludin concentration; reduced the diarrhea rate of weaned piglets by 28%, gastric pH, ileal pH, cecal pH and urine pH, MDA, crypt depth; improved the diversity of cecal microflora. YSE and CU could improve the growth performance, reduce the diarrhea rate, improve intestinal health, and increase the diversity and abundance of cecal microflora in weaned piglets and expected to be used as antibiotics alternative feed additives in the production of weaned piglets.

A Comparative Study on the Biodegradation of 17β-Estradiol by Candida utilis CU-2 and Lactobacillus casei LC-1

The release and fate of estrogens have attracted more and more public attention. Biodegradation is an important method for estrogen removal from the environment. However, few comparative studies concentrated on the degradation of 17β-estradiol (E2) by fungi and bacteria. In this study, the removal efficiencies of E2 by fungi (Candida utilis CU-2) and bacteria (Lactobacillus casei LC-1) were investigated through influencing factors, kinetics, and biodegradation pathways. The results demonstrated that both C. utilis CU-2 and L. casei LC-1 have the same degradation efficiency, and they can effectively degrade E2 (10 μM) with nearly 97% degradation efficiency. However, the biodegradation efficiency of the two strains only reached 20% when E2 was used as a sole carbon source, while it increased to 97% with 1.2 g/L sucrose, glucose, or sodium acetate supply, indicating the occurrence of co-metabolism. In addition, the results indicated that 35°C and 0.6 g/L sucrose favored the degradation. However, the addition of excessive carbon sucrose (10 g/L) significantly inhibited the biodegradation of E2. Besides, the degradation of E2 with ~0–10 g/L sucrose as co-substrate followed the first-order kinetics well. Through intermediate products analysis, 12 degradation products were identified, and they were mainly produced via hydroxylation and methylation, among others, among which C14H22O4 (m/z:[M + H]+ = 255) was detected as the product with the smallest amount of carbon in this study. Based on the detected products and previous studies, five biodegradation pathways were proposed. To our knowledge, there are few reports about the comparisons of E2 removal between fungi and bacteria. Moreover, the results confirmed that the strain CU-2 and the strain LC-1 may have similar degradation characteristics and metabolic mechanisms in the degradation of E2. This study may provide a promising bio-treatment method with low energy consumption for E2 removal from aqueous environments and help in understanding their biodegradation mechanisms.