Pichia pastoris, a methylotrophic yeast, is known to be an efficient host for heterologous proteins production. In this study, a recombinant P. pastoris Y11430 was found better for β-glucosidase activity in comparison with a wild type P. pastoris Y11430 strain, and thereby, subjected to methanol intermittent feed profiling for β-glucosidase production. The results showed that at 72 h of cultivation time, the cultures with 16.67% and 33.33% methanol feeding with constant rate could produce the total dry cell weight of 52.23 and 118.55 g/L, respectively, while the total mutant β-glucosidase activities were 1001.59 and 3259.82 units, respectively. The methanol feeding profile was kept at 33% with three methanol feeding strategies such as constant feed rate, linear feed rate, and exponential feed rate which were used in fed-batch fermentation. At 60 h of cultivation, the highest total mutant β-glucosidase activity was 2971.85 units for exponential feed rate culture. On the other hand, total mutant β-glucosidase activity of the constant feed rate culture and linear feed rate culture were 1682.25 and 1975.43 units, respectively. The kinetic parameters of exponential feed rate culture were specific growth rate on glycerol 0.228/h, specific growth of methanol 0.061/h, maximum total dry cell weight 196.73 g, yield coefficient biomass per methanol ([Formula: see text]) 0.57 gcell/gMeOH, methanol consumption rate ([Formula: see text]) 5.76 gMeOH/h, and enzyme productivity ([Formula: see text]) 75.96 units/h. In conclusion, higher cell mass and β- glucosidase activity were produced under exponential feed rate than constant and linear feed rates.

• Klíčová slova
• Exponential feed rate, Fed-batch fermentation, Methanol feeding profile, Pichia pastoris, β-glucosidase,
• MeSH
• bioreaktory MeSH
• celulasy * metabolismus   MeSH
• fermentace MeSH
• methanol * metabolismus   MeSH
• Pichia metabolismus   MeSH
• rekombinantní proteiny genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• celulasy * MeSH
• methanol * MeSH
• rekombinantní proteiny MeSH

In our experiment, the effects of 5, 10 and 20 mg cadmium per kg dry matter (DM) on protozoan population and rumen fermentation of feed ration consisting of 11.7 g DM of hay and 2.8 g DM of barley (80: 20%) were followed in artificial rumen (Rusitec). The results of the experiment showed that the addition of 5 and 10 mg cadmium per kg DM less significantly (P < 0.05) decreased the digestibility of DM, organic matter and neutral detergent fibre and significantly (P < 0.01) decreased the digestibility of cellulose of feed ration. It is interesting that the addition of 20 mg cadmium per kg DM did not influence these parameters. Although the total gas production showed a tendency of decrease due to the influence of the addition of 5, 10 and 20 mg cadmium/kg DM, methane and CO2 production was not altered. However, cadmium significantly influenced the production of individual volatile fatty acids-VFA's (mmol/day). The addition of 5, 10 and 20 mg cadmium per kg DM significantly increased acetic acid production (by 10-20%) and decreased propionic acid production (by 18-30%). Therefore, the acetate: propionate ratio was significantly increased (from 1.57 to 2.45-2.60) by the addition of cadmium. The production of n-valeric and iso-valeric acids was also significantly decreased in comparison with the control. The decrease of individual VFA's was more significant at the higher amount of cadmium added into the fermentation system. The proportions of individual VFA's in total VFA production expressed in molar % showed a similar character. The changes in the production of individual VFA's due to the influence of the addition of 5, 10 and 20 mg cadmium per kg DM caused a decrease in energetic efficiency of VFA's (P < 0.001) in comparison with the control. The other parameters of rumen fermentation - utilization of glucose, adenosine triphosphate (ATP) production, fermented hexose, fermented amino acids and fermented organic matter (OMF) were not influenced by the cadmium addition. Although the total microbial matter production in effluent and undigested feed (residues) was significantly (P < 0.001) decreased by the addition of 5, 10 and 20 mg cadmium per kg DM, the efficiency of microbial synthesis expressed as YATP and g microbial N/kg OMF was not changed and achieved the values 11.78-12.68 (YATP), 25.56-28.35 (g microbial N/kg OMF), respectively. The total protozoan population was significantly decreased by the cadmium addition mainly as a result of the decrease of infusoria of Entodinium spp.(ABSTRACT TRUNCATED AT 400 WORDS)

• MeSH
• bachor parazitologie   fyziologie   MeSH
• Eukaryota účinky léků   růst a vývoj   MeSH
• fermentace MeSH
• kadmium farmakologie   MeSH
• krmivo pro zvířata MeSH
• ovce parazitologie   fyziologie   MeSH
• techniky in vitro MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• kadmium MeSH

An experiment was conducted with rumen pouch (RUSITEC--Rumen Simulation Technique). In four fermentation vessels (V), percent proportions of hay and barley were as follows: V1--40:60, V2 - 60:40, V3--80:20 and V4--100:0. Every day 5 mg of monensin dissolved in 1 ml 96% ethanol were added to each fermentation vessel. All diets were isonitrogenous, and after an addition of urea the crude protein (CP) content made 13% in each diet. The experiment lasted 12 days: so called steady state period took the first six days when the fermentation conditions were stabilized. Monensin reduced dry matter digestibility, production of total volatile fatty acids, acetic acid, n-butyric and isovaleric acids and acetate: propionate proportion, and it increased the production of propionic and n-valeric acids. The production of methane and CO2 decreased. The higher proportion of hay in diets decreased dry matter digestibility, digestibility of detergent fibre, total and individual volatile fatty acids, CO2, methane energy yield of volatile fatty acids (E), glucose utilization, production of adenosine triphosphate and production of fermented hexoses. The production, utilization and recovery of metabolic hydrogen also decreased. The effectiveness of microbial matter synthesis (YATP = 11.3) was highest during the fermentation of feed containing 60% hay and 40% barley.

• MeSH
• bachor fyziologie   MeSH
• fermentace účinky léků   MeSH
• krmivo pro zvířata * MeSH
• monensin farmakologie   MeSH
• techniky in vitro MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• monensin MeSH

Previous studies indicated an intrinsic relationship between infant diet, intestinal microbiota composition and fermentation activity with a strong focus on the role of breastfeeding on microbiota composition. Yet, microbially formed short-chain fatty acids acetate, propionate and butyrate and other fermentation metabolites such as lactate not only act as substrate for bacterial cross-feeding and as mediators in microbe-host interactions but also confer antimicrobial activity, which has received considerably less attention in the past research. It was the aim of this study to investigate the nutritional-microbial interactions that contribute to the development of infant gut microbiota with a focus on human milk oligosaccharide (HMO) fermentation. Infant fecal microbiota composition, fermentation metabolites and milk composition were analyzed from 69 mother-infant pairs of the Swiss birth cohort Childhood AlleRgy nutrition and Environment (CARE) at three time points depending on breastfeeding status defined at the age of 4 months, using quantitative microbiota profiling, HPLC-RI and 1H-NMR. We conducted in vitro fermentations in the presence of HMO fermentation metabolites and determined the antimicrobial activity of lactate and acetate against major Clostridiaceae and Peptostreptococcaceae representatives. Our data show that fucosyllactose represented 90% of the HMOs present in breast milk at 1- and 3-months post-partum with fecal accumulation of fucose, 1,2-propanediol and lactate indicating fermentation of HMOs that is likely driven by Bifidobacterium. Concurrently, there was a significantly lower absolute abundance of Peptostreptococcaceae in feces of exclusively breastfed infants at 3 months. In vitro, lactate inhibited strains of Peptostreptococcaceae. Taken together, this study not only identified breastfeeding dependent fecal microbiota and metabolite profiles but suggests that HMO-derived fermentation metabolites might exert an inhibitory effect against selected gut microbes.

• Klíčová slova
• Exclusively breastfeeding, HMO fermentation metabolites, Peptostreptococcaceae, gut microbiota, lactate,
• MeSH
• acetáty metabolismus   MeSH
• antiinfekční látky * metabolismus   MeSH
• Clostridiales metabolismus   MeSH
• dítě MeSH
• feces mikrobiologie   MeSH
• fermentace MeSH
• kojenec MeSH
• kojení MeSH
• kyselina mléčná metabolismus   MeSH
• lidé MeSH
• mateřské mléko chemie   MeSH
• oligosacharidy metabolismus   MeSH
• střevní mikroflóra * MeSH
• Check Tag
• dítě MeSH
• kojenec MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• acetáty MeSH
• antiinfekční látky * MeSH
• kyselina mléčná MeSH
• oligosacharidy MeSH

Lactobacilli are commonly used as probiotics in poultry to improve production parameters and to increase chicken resistance to enteric infections. However, lactobacilli do not efficiently colonise the chicken intestinal tract, and also, their anti-infection effect in vivo is sometimes questionable. In this study, we therefore evaluated the potential of a mixture of four Lactobacillus species (L. salivarius, L. reuteri, L. ingluviei and L. alvi) for the protection of chickens against Salmonella Enteritidis infection. Whenever the chickens were inoculated by lactobacilli and S. Enteritidis separately, there was no protective effect of lactobacilli. This means that when lactobacilli and S. Enteritidis are exposed to each other as late as in the crop of chickens, lactobacilli did not influence chicken resistance to S. Enteritidis at all. The only positive effect was recorded when the mixture of lactobacilli and S. Enteritidis was used for the inoculation of feed and the feed was anaerobically fermented for 1 to 5 days. In this case, chickens fed such a diet remained S. Enteritidis negative. In vitro experiments showed that the protective effect was caused by acidification of feed down to pH 4.6 due to lactobacilli fermentation and was associated with S. Enteritidis inactivation. The probiotic effect of lactobacilli was thus expressed in the feed, outside the chicken host.

• Klíčová slova
• Lactobacillus, Salmonella Enteritidis, chicken, feed fermentation, gut microbiota, probiotic,
• Publikační typ
• časopisecké články MeSH

An experiment was made with the Rumen Simulation Technique (Rusitec) in which the fermentation of a mixed ration of hay (12.8 g/d) and bruised barley (3.2 g/d) was compared with the fermentation of the same diet in the presence of 5 mg monensin/d from the USA, CSFR and Bulgaria. The fermentation of the mixed ration was significantly affected by all three kinds of monensin. The digestibility of dry matter (DM) in the rations declined in the presence of monensin from 48% to 40% (tab. I). The digestibility of detergent fibre, cellulose and hemicellulose also declined in the presence of monensin (tab. I). The production of methane decreased (-70%) and CO2 production dropped too, but this decrease could be accounted for by the changes in the production of volatile fatty acids and redistribution of metabolic hydrogen (tab. I). Monensin decreased the production of total volatile fatty acids (-21%), the production of acetic (-35%), n-butyric, n-valeric and isovaleric acids (tab. II) and increased the production of propionic acid (+60%). The production, utilization and recovery of metabolic hydrogen were significantly increased in the presence of all three kinds of monensin (tab. IV). The end products of fermentation were affected by an addition of monensin to the mixed ration. All three kinds of monensin increased energic efficiency of volatile fatty acids, decreased adenosinetriphosphate (ATP) production, the amounts of fermented hexose, organic matter fermented and utilization of glucose (tab. III).(ABSTRACT TRUNCATED AT 250 WORDS)

• MeSH
• bachor fyziologie   MeSH
• biologické modely MeSH
• fermentace účinky léků   MeSH
• krmivo pro zvířata * MeSH
• monensin farmakologie   MeSH
• techniky in vitro MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• monensin MeSH

A batch culture technique was used to evaluate dry matter (DM) digestibility of corn stover (Zea mays L.) and kudzu, Pueraria montana (Lour.) Merr. after solid-state fermentation (SSF) with a white-rot fungus, Pleurotus ostreatus (Jacq. ex Fr.) P. Kumm. Five dietary treatments consisting of mixtures of corn stover (C) and kudzu (K) in varying ratios, (1) 100C:0K, (2) 75C:25K, (3) 50C:50K, (4) 25C:75K, and (5) 0C:100K, were inoculated with P. ostreatus (MBFBL 400) and subjected to SSF for 0, 35, and 77 days. The study was arranged as a 5 × 3 factorial design with 3 replicates. Grass hay was included in the study as a control. Interactions (P < 0.05) between treatments and fermentation time were noted for the fermentation kinetics. Asymptotic gas was the highest (P < 0.05) for 0C:100K and 100C:0K on day 77. Treatment effect (P < 0.001) and treatment × fermentation time interaction (P < 0.001) were noted for in vitro dry matter digestibility (IVDMD). On day 77, treatment 4 had the highest (P < 0.001) IVDMD value, while treatment 1 had the lowest (P < 0.001) IVDMD. There was no difference (P > 0.05) between treatments 3, 5, and control. Numerically, the ranking of their IVDMD values from the highest to the lowest is 4 > 2 > 5 > control >3 > 1. The results show that the treated corn stover and kudzu mixes were comparable with the control, which is good quality hay. This is the first report that demonstrates the potential use of a combined mixture of corn stover and kudzu in ruminant animal feed development.

• MeSH
• biomasa MeSH
• fermentace MeSH
• kinetika MeSH
• krmivo pro zvířata analýza   mikrobiologie   MeSH
• kukuřice setá chemie   mikrobiologie   MeSH
• nutriční hodnota * MeSH
• Pleurotus metabolismus   MeSH
• plyny metabolismus   MeSH
• Pueraria chemie   mikrobiologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• plyny MeSH

In trial with adult wethers and weaned lambs the effect of enzymatic preparation Pektofoetidin G3x (mostly pectinase and cellulase) on rumen fermentation was studied. After 4 weeks of Pektofoetidin G3x application (0.54 g per day and animal) to adult wethers no statistically significant differences in total volatile fatty acids (VFA), acetic acid, propionic acid, butyric acid, ammonia in the rumen contents and urea in blood were determined between control and enzyme treated group. In comparison of fermentation parameters in wethers (mean of 1-3 hours after feeding) and lambs (2-3 hours after feeding) the significant differences in mol % of acetic acid (63.3 in control, 54.6 in experimental group, P less than 0.01), propionic acid (24.6, vs. 31.3, P less than 0.001), acetate: proprionate ratio (2.54, vs. 1.77, P less than 0.01) and in energy efficiency of VFA production (76.0%, vs. 79.1%, P less than 0.001) were determined. These differences between wethers and lambs suggest more intensive fermentation in lambs than in adult sheep. On the basis of these results it is possible to suggest, that in adult animals the efficiency of application of enzymatic preparations is low. In utilization of enzymatic preparations more important role, probably, is that of ruminal ecosystem itself, that, if once fully developed, is perfectly resistant to biotechnological interferences.

• MeSH
• acetáty metabolismus   MeSH
• amoniak metabolismus   MeSH
• bachor metabolismus   MeSH
• butyráty metabolismus   MeSH
• fermentace účinky léků   MeSH
• glykosidhydrolasy farmakologie   MeSH
• koncentrace vodíkových iontů MeSH
• krmivo pro zvířata MeSH
• kyselina octová MeSH
• kyseliny mastné těkavé metabolismus   MeSH
• močovina krev   MeSH
• ovce metabolismus   MeSH
• polygalakturonasa farmakologie   MeSH
• propionáty metabolismus   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• acetáty MeSH
• amoniak MeSH
• butyráty MeSH
• glykosidhydrolasy MeSH
• kyselina octová MeSH
• kyseliny mastné těkavé MeSH
• močovina MeSH
• polygalakturonasa MeSH
• propionáty MeSH

Two groups of bullocks, each consisting of 125 animals, were subjected to a trial to study the effect of monensin (Rumensin premix) administered at doses from 125 to 175 mg per head/day on rumen fermentation and weight gains. For 135 days the animals were given a diet based on green juicy forage with a supplement of chopped straw and concentrate mixture; this mixture contained 20-30% of dried poultry droppings. In the experimental group with monensin, the concentration of total and protein nitrogen and the molar percentage of propionic acid significantly increased (23.7 and 28.5%, respectively, P less than 0.01) and the acetate: propionate ratio decreased four hours after feeding. Further, the energy yield of the production by volatile fatty acids (VFA) significantly increased in the rumen contents (76.89%, 78.64%, respectively, P less than 0.05). The levels of ammonia and non-protein nitrogen were not affected by the addition of monensin. The average daily live weight gains were 713 g in the control group and 800 g in the experimental group; this means that the gains of the experimental animals rose by 12.2%. Monensin had a positive influence on the proportions of the rumen-produced VFA in favour of propionic acid which, in turn, favourably influenced the energy balance of nutrient conversion and efficiency.

• MeSH
• bachor účinky léků   metabolismus   MeSH
• fermentace účinky léků   MeSH
• krmivo pro zvířata * MeSH
• kyseliny mastné těkavé metabolismus   MeSH
• monensin farmakologie   MeSH
• skot fyziologie   MeSH
• tělesná hmotnost účinky léků   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• skot fyziologie   MeSH
• zvířata MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH
• Názvy látek
• kyseliny mastné těkavé MeSH
• monensin MeSH

Wethers were subjected to experiments aimed at studying the possibility of replacing part of bulk fodder by treated beech sawdust and its effect on ruminal fermentation in the case of administration of chopped and unchopped hay. For a period of 24 weeks the animals consumed 1000 g of diet dry matter daily; the diet contained 41.81% of chopped meadow hay, 25.28% of barley, 15.37% of chopped straw, 14.98% of molasses, 1.32% of urea and 1.24% of mineral supplement. In the test group the 15.37% proportion of straw was replaced by sawdust. In the subsequent ten-week period the animals were given the same diets, but the hay was not chopped. On the whole the experiment was performed with two groups with straw and two with sawdust. In the groups with chopped hay the sawdust in the diet increased the molar percentage of acetic acid, reduced the molar percentage of propionic acid (which resulted in an increased acetate: propionate ratio), and reduced the pH value and energy efficiency of the produced volatile fatty acids (VFA). The levels of total VFA were not affected. In the groups fed unchopped (long) hay the diet with 15.37% of sawdust showed a significant increase in total VFA and in the molar percentage of butyric acid as well as in the energy efficiency of VFA in rumen. The acetate: propionate ratio was not changed, probably owing to sufficient production of acetic acid. Although some variability was recorded in the results, it can be stated that treated beech sawdust had no adverse effect on rumen fermentation and that the replacement of part of bulk forage by this sawdust was successful. A relationship was also found between sawdust and the physical form of the bulk fodder contained in the ration.

• MeSH
• bachor fyziologie   MeSH
• dřevo * MeSH
• fermentace MeSH
• krmivo pro zvířata * MeSH
• ovce fyziologie   MeSH
• potravní vláknina * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH