CLASSEN H.L.,University of Saskatchewan |
APAJALAHTI J.,Alimetrics Ltd. |
SVIHUS B.,Norwegian University of Life Sciences |
CHOCT M.,University of New England of Australia
World's Poultry Science Journal | Year: 2016
The importance of the crop is often underestimated in poultry production. In addition to storing ingested feed, it also can impact nutrient digestion by digesta softening and the initial activity of feed (endogenous and exogenous) and microbial enzymes. The crop represents the first major defence against poultry pathogens and zoonotic organisms with well established adaptive and innate immune function, and a lactobacilli dominated microbiota capable of reducing the passage of these organisms further along the digestive tract. However, the potential to improve bird productivity and health, as well as affect meat and egg safety, are influenced by the nature of the diet, and in particular feed entry and extended presence in the crop. This is required to promote lactobacilli fermentation, the production of lactic acid and other volatile fatty acids, and the lowering of crop pH. Management practices such as meal feeding and the use of lighting programs with extended dark periods encourage crop utilisation. Further, the use of feed additives such as prebiotics and probiotics may enhance crop function, which in turn contributes to well-being of the entire digestive tract. A healthy and functional crop, along with other segments of digestive tract, has increased importance in an era of reduced antibiotic use in poultry feeds. Copyright © World's Poultry Science Association2016
Pavsic-Vrtac K.,University of Ljubljana |
Ojanpera S.,Alimetrics Ltd |
Apajalahti J.,Alimetrics Ltd |
Srimpf K.,University of Ljubljana |
Tavcar-Kalcher G.,University of Ljubljana
Food Analytical Methods | Year: 2014
An analytical procedure for the determination of aflatoxin B1 in eggs was introduced and validated in laboratory 1. The method consisted of the extraction of aflatoxin B1 from a sample, purification of the extract with solvents, immunoaffinity column cleanup and the determination by liquid chromatography with post-column bromination and fluorescence detection at λex = 362 nm and λem = 425 nm. The method was transferred to laboratory 2, where it was modified and validated. The limit of detection (LOD) and limit of quantification (LOQ) obtained in laboratory 1 were 2 and 6 ng/kg, respectively, and 2 and 5 ng/kg in laboratory 2, respectively. The repeatability of measurements in laboratory 1, represented by differences between results of duplicate measurements, was 10 ng/kg at the contamination level of 50 ng/kg. At the same concentration level, the standard deviation (sR) and the relative standard deviation (RSDR) for the within-laboratory reproducibility were 5.5 ng/kg and 11 %, respectively, and the measurement uncertainty was ±10 ng/kg. The mean recovery was 70 %. In laboratory 2, the repeatability of measurements at the contamination level of 20 ng/kg, represented by the standard deviation (sR), repeatability (r) and relative standard deviation (RSDR) was 4 ng/kg, 11 ng/kg and 20 %, respectively, and the recovery was 67 %. The results indicate that the procedures are suitable for the determination of aflatoxin B1 in eggs and can be implemented for the routine analysis. Using the procedure validated in laboratory 1, 25 samples from farms in Slovenia were analysed. In none of the analysed samples, aflatoxin B1 was detected. © 2014, Springer Science+Business Media New York.
Aro H.,Mtt Agrifood Research Finland |
Jarvenpaa E.,Mtt Agrifood Research Finland |
Makinen J.,Mtt Agrifood Research Finland |
Lauraeus M.,Alimetrics Ltd |
And 2 more authors.
LWT - Food Science and Technology | Year: 2013
Oats contain ingredients that have potential health-promoting properties. Oat lipids contain several essential fatty acids. The polar lipids in oats include glycolipids and phospholipids, which are typically extracted from oat flakes with polar organic solvents. Supercritical carbon dioxide (SC-CO2) has been proposed as an alternative to organic solvents in the food sector for environmental and safety reasons. SC-CO2 was used in this study without and with ethanol as a co-solvent to isolate the polar lipid fractions from oat flakes with or without heat treatments. The polar lipids were collected as a solution in ethanol and precipitated using SC-CO2 as an antisolvent. The fatty acid compositions of different lipid fractions were determined. The precipitated oat polar lipids were tested as an encapsulative and protective agent of probiotics in a human digestive tract simulation. The protective effects of the oat polar lipids were evaluated by measuring the gas production, microbial activity, acetic and lactic acid production, and pH changes in different test mediums. The results demonstrate that the oat polar lipids are able to protect Bifidobacterium breve in a phosphate buffer, thereby providing a useful stabilization method to improve the shelf life of probiotic products. © 2013 Elsevier Ltd.
Vaara M.,Northern Antibiotics Ltd. |
Vaara M.,University of Helsinki |
Siikanen O.,Alimetrics Ltd. |
Apajalahti J.,Alimetrics Ltd. |
And 7 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2010
Polymyxins are cationic lipopeptides (five cationic charges) and the last resort for the treatment of serious Gram-negative infections caused by multiresistant strains. NAB741 has a cyclic peptide portion identical to that of polymyxin B but carries in the linear peptide portion a threonyl-D-serinyl residue (no cationic charges) instead of the diaminobutyryl-threonyl- diaminobutyryl residue (two cationic charges). At the N terminus of the peptide, NAB741 carries an acetyl group instead of a mixture of methyl octanoyl and methyl heptanoyl residues. NAB741 sensitized Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, and Acinetobacter baumannii to antibiotics against which the intact outer membrane is an effective permeability barrier. When tested by using Etest strips on plates containing increasing concentrations of NAB741, the fractional inhibition concentration index (FICI) of the combination of NAB741 with rifampin ranged from ≤0.111 to 0.158 and that with clarithromycin from ≤0.094 to 0.292. When tested by the checkerboard method, the corresponding FICI values against E. coli ATCC 25922 were ≤0.141 to ≤0.155 with rifampin and 0.094 with clarithromycin. In addition, at 4 μg/ml, NAB741 decreased the MICs of azithromycin, mupirocin, fusidic acid, and vancomycin for E. coli strains and E. cloacae by factors ranging from 8 to 200. A sister peptide, NAB752, carrying a threonyl-aminobutyryl residue as the linear peptide portion, was inactive. Furthermore, NAB741 sensitized E. coli to the bactericidal activity of fresh guinea pig serum. The renal clearance of NAB741 was approximately 400-fold, 16-fold, and 8-fold higher than those measured for colistin, NAB7061, and NAB739, respectively. Copyright © 2010, American Society for Microbiology. All Rights Reserved.
Hang I.,University of Helsinki |
Rinttila T.,Alimetrics Ltd. |
Zentek J.,Free University of Berlin |
Kettunen A.,Alimetrics Ltd. |
And 6 more authors.
BMC Veterinary Research | Year: 2012
Background: Considerable evidence suggests that food impacts both the gastro-intestinal (GI) function and the microbial ecology of the canine GI tract. The aim of this study was to evaluate the influence of high-carbohydrate (HC), high-protein (HP) and dry commercial (DC) diets on the canine colonic microbiota in Beagle dogs. Diets were allocated according to the Graeco-Latin square design. For this purpose, microbial DNA was isolated from faecal samples and separated by density gradient centrifugation, resulting in specific profiling based on the guanine-cytosine content (%G + C). In addition, 16 S rRNA gene amplicons were obtained from the most abundant %G + C peaks and analysed by sequence analysis, producing a total of 720 non-redundant sequences (240 sequences per diet).Results: The DC diet sample showed high abundance of representatives of the orders Clostridiales, Lactobacillales, Coriobacteriales and Bacteroidales. Sequence diversity was highest for DC diet samples and included representatives of the orders Lactobacillales and Bacteroidales, which were not detected in samples from the HP and HC diets. These latter two diets also had reduced levels of representatives of the family Lachnospiraceae, specifically Clostridial cluster XIVa. The HC diet favoured representatives of the order Erysipelotrichales, more specifically the Clostridial cluster XVIII, while the HP diet favoured representatives of the order Fusobacteriales.Conclusions: This study detected Coriobacteriales in dog faeces, possibly due to the non-selective nature of the %G + C profiling method used in combination with sequencing. Moreover, our work demonstrates that the effect of diet on faecal microbiota can be explained based on the metabolic properties of the detected microbial taxa. © 2012 Hang et al.; licensee BioMed Central Ltd.
Susceptibility of carbapenemase-producing strains of Klebsiella pneumoniae and Escherichia coli to the direct antibacterial activity of NAB739 and to the synergistic activity of NAB7061 with rifampicin and clarithromycin
Vaara M.,Northern Antibiotics Ltd |
Vaara M.,University of Helsinki |
Siikanen O.,Alimetrics Ltd |
Apajalahti J.,Alimetrics Ltd |
And 2 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2010
Objectives: To determine the susceptibility of carbapenemase-producing strains of Klebsiella pneumoniae and Escherichia coli to the direct antibacterial activity of NAB739 and to the synergistic activity of NAB7061 with rifampicin and clarithromycin. NAB739 and NAB7061 are novel polymyxin derivatives that lack the cationic charges in the linear peptide portion of polymyxin B and have pharmacokinetic properties different from those of polymyxin B. Methods: MIC determinations were performed by the agar dilution method using CLSI guidelines. Polymyxin B was used as a comparison. Synergism studies measured fractional inhibitory concentration indices (FICIs) by using increasing concentrations of the compounds in Mueller-Hinton agar and Etests™. Results: The MICs of NAB739 for all nine polymyxin-susceptible, carbapenemase-producing strains were identical or very close to those determined for E. coli ATCC 25922, for K. pneumoniae ATCC 13883, as well as for 18 clinical carbapenem-susceptible isolates. At a concentration of 4 mg/L, NAB7061 decreased the MIC of rifampicin and clarithromycin for all carbapenemase strains by factors ranging from 6 to 500. The polymyxin-resistant strain K. pneumoniae CL5762B was sensitized by a factor of 24 to rifampicin (FICI, 0.167) and by a factor of 12 to clarithromycin (FICI, 0.208). Conclusions: Polymyxin-susceptible, carbapenemase-producing strains are as susceptible to NAB739 as are the carbapenem-susceptible clinical isolates. In addition, NAB7061 has notable synergism with rifampicin and clarithromycin against all the carbapenemase-producing strains tested, including the polymyxin-resistant K. pneumoniae strain. © The Author 2010. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.
Rinttila T.,University of Helsinki |
Rinttila T.,Alimetrics Ltd |
Lyra A.,University of Helsinki |
Lyra A.,Danisco |
And 2 more authors.
Gut Pathogens | Year: 2011
Background: Growing amount of scientific evidence suggests that microbes are involved in the pathophysiology of irritable bowel syndrome (IBS). The predominant fecal microbiota composition of IBS subjects has been widely studied with DNA-based techniques but less research has been focused on the intestinal pathogens in this disorder. Here, we optimized a highly sensitive panel of 12 quantitative real-time PCR (qPCR) assays to shed light on the putative presence of intestinal pathogens in IBS sufferers. The panel was used to screen fecal samples from 96 IBS subjects and 23 healthy controls. Results: Fifteen IBS samples (17%) tested positive for Staphylococcus aureus with a thermonuclease (nuc) gene-targeting qPCR assay, whereas none of the healthy controls were positive for S. aureus (p < 0.05). The S. aureus -positive IBS samples were confirmed by sequencing of the PCR amplicons. Clostridium perfringens was detected from IBS and control groups with a similar frequency (13% and 17%, respectively) with -toxin (plc) gene -targeting qPCR assay while none of the samples tested positive for the Cl. perfringens enterotoxin-encoding gene (cpe). Conclusions: The qPCR panel consisting of 12 assays for an extensive set of pathogenic microorganisms provides an efficient alternative to the conventional detection of gastrointestinal pathogens and could accelerate the initiation of targeted antibiotic therapy reducing the risk of post-infectious IBS (PI-IBS). S. aureus has not been previously reported to be associated with the onset of IBS. Although we discovered significant differences in the prevalence of S. aureus between the study groups, its importance in giving rise to IBS symptoms requires further studies. © 2011 Rinttilä et al; licensee BioMed Central Ltd.
Comparison of the sequestering properties of yeast cell wall extract and hydrated sodium calcium aluminosilicate in three in vitro models accounting for the animal physiological bioavailability of zearalenone
Yiannikouris A.,Alltech Inc. |
Kettunen H.,Alimetrics Ltd |
Apajalahti J.,Alimetrics Ltd |
Pennala E.,Alimetrics Ltd |
Moran C.A.,Alltech France
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2013
The sequestration/inactivation of the oestrogenic mycotoxin zearalenone (ZEA) by two adsorbents - yeast cell wall extract (YCW) and hydrated sodium calcium aluminosilicate (HSCAS) - was studied in three laboratory models: (1) an in vitro model was adapted from referenced methods to test for the sequestrant sorption capabilities under buffer conditions at two pH values using liquid chromatography coupled to a fluorescence detector for toxin quantification; (2) a second in vitro model was used to evaluate the sequestrant sorption stability according to pH variations and using 3H-labelled ZEA at low toxin concentration; and (3) an original, ex vivo Ussing chamber model was developed to further understand the transfer of ZEA through intestinal tissue and the impact of each sequestrant on the mycotoxin bioavailability of 3H-labelled ZEA. YCW was a more efficient ZEA adsorbent than HSCAS in all three models, except under very acidic conditions (pH 2.5 or 3.0). The Ussing chamber model offered a novel, ex vivo, alternative method for understanding the effect of sequestrant on the bioavailability of ZEA. The results showed that compared with HSCAS, YCW was more efficient in sequestering ZEA and that it reduced the accumulation of ZEA in the intestinal tissue by 40% (p < 0.001). © 2013 Alltech.
Apajalahti J.,Alimetrics Ltd |
Vienola K.,Alimetrics Ltd
Animal Feed Science and Technology | Year: 2016
The different sections of the broiler chicken intestinal tract are inhabited by specialist microbiota adapted to the physicochemical conditions, host physiology and available nutrients of the specific habitat. The small intestine is dominated by lactic acid bacteria which have complex nutrient requirements resembling those of the chicken host itself. Lactobacilli are unable to synthesise amino acids for their anabolism and are therefore highly dependent on amino acid availability in the growth environment. Thus, in the small intestine there is competition for amino acids between the microbiota and the chicken host. According to rough estimates, lactobacilli in the small intestine may assimilate 3-6% of total dietary amino acids. If the protein is highly digestible and amino acids are largely absorbed in the upper small intestine, where bacterial growth is suppressed, the proportion captured by the host may be higher. Exogenous enzymes which promote protein digestion are also likely to provide a competitive advantage to the chicken, offering less growth potential for amino acid-dependent bacteria.Protein escaping the ileum comprises resistant protein of dietary origin, protein assimilated to intestinal bacteria and endogenous protein synthesised and secreted by the host, the latter synthesised in host tissues from dietary amino acids and thus representing true endogenous protein. Activities of small intestinal bacteria affect the size of the microbial protein fraction and also the production of endogenous proteins originating from mucin, epithelial cells and antibodies.Ileal bypass protein is subject to fermentation by putrefactive bacteria in the caecum. Putrefaction produces many harmful and toxic compounds, which in high concentrations may have adverse effects on chicken growth and performance. The protein fermentation products include amines, indoles, phenols, cresol and ammonia, which can all negatively affect host or cell health. All actions to reduce the amount of ileal bypass protein potentially also reduce production of toxic protein fermentation metabolites in the caecum. Enzymes which facilitate protein digestion in the upper intestine and soluble carbohydrates resistant to ileal digestion both reduce caecal putrefaction. In the distal intestine, saccharolytic fermentation is preferred and putrefaction accelerates only when utilisable carbohydrates are depleted. Soluble oligo- and polysaccharides are produced in situ by non-starch polysaccharide degrading enzymes and can also be added directly to the diet as health-promoting prebiotics. © 2016 Elsevier B.V.
Rinttila T.,Alimetrics Ltd |
Apajalahti J.,Alimetrics Ltd
Journal of Applied Poultry Research | Year: 2013
Microbiota in the intestine of an animal species has evolved together with the host. This coevolution has produced specific host-microbe combinations, called superorganisms, with the best possible fitness in a given environment. Intestinal microbiota has an enormous metabolic potential and it affects both the nutrition and health of the host. The importance of intestinal microbiota for the performance of broiler chickens has been studied for decades. The microbial community structure of the cecum is significantly more complex and less well characterized than that of the crop and small intestine. Culture-independent molecular techniques have recently been introduced to bring fresh insights into the intestinal system of the broiler chicken. As a consequence, there is growing evidence of connection between the apparent metabolizable energy of the diet and microbiota composition in the hindgut of the host. This connection can be due to direct conversion of some dietary components into high-energy metabolites by specialized bacteria. The utilization of such fermentation end products would provide more energy for the host, which could be measured as improved feed conversion efficiency. However, it is also possible that cecal microbial profile is a reflection of feed digestion and nutrient absorption efficiency in the proximal intestine. Disorders in these functions cause excess nutrient bypass to the lower intestine, providing new, easily available substrates for bacteria that could otherwise not compete in that habitat. The 2 causal links described are likely to coexist in real life situations, but their relative dominance warrants further well-designed studies. © 2013 Poultry Science Association, Inc.