Effects of oral administration of different dosages of carvacrol essential oils on intestinal barrier function in broilers.

Essential oils are widely used in the pharmaceutical, food and cosmetic industries, and many plant essential oils have shown that they have positive effects on broilers nutrition. This experiment was conducted to study the effects of orally administered different dosages of carvacrol essential oils on intestinal barrier function in broiler chickens. A total of eighty 28-day-old (1.28 ± 0.15 kg) ROSS 308 broilers were randomly allocated to four groups of 20 replicates each, with one chicken per replicate per cage, and all were fed with the same diet. Four experimental groups were orally administered 0, 200, 300 or 400 µl carvacrol essential oils at 18:00 hr every day during the 2-week experimental period. As a result of which, the gene expression of the occludin, claudin-1, claudin-5, ZO-1 and ZO-2 in intestinal mucosa of small intestine (p < 0.05) and the goblet cell content in small intestine epithelium (p < 0.05) were significantly increased; test subjects with 300 or 400 µl carvacrol essential oils reduced the microbial counts of Salmonella spp. and Escherichia coli in the intestines (p < 0.05); Essential oils administration also significantly increased activity of the sucrase (p < 0.05) and lactase (p < 0.05) in intestinal mucosa. In conclusion, the carvacrol essential oils have positive effects on growth performance and intestinal barriers function of broilers; those effects may be related to the dosage, as administration of 300 or 400 µl was more effective than that of 200 µl.

The anti-aging properties of a human placental hydrolysate combined with dieckol isolated from Ecklonia cava.

BACKGROUNDS: In the present study, we aimed to examine the anti-aging properties of human placental hydrolysate (HPE) and dieckol (DE) from Ecklonia cava against free radical scavenging, muscle hypertrophy-related follistatin mRNA expression, amelioration of cognition-related genes and proteins, inhibition of collagenase-regulating genes, and elastinase activity. METHODS: The anti-aging effects were examined in human fibroblast (CCD986sk), mouse myoblast (C2C12), and neuroblastoma (N2a) cell models, by employing various assays such as 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) scavenging, hydroxyl radical-mediated oxidation, quantitative real-time polymerase chain reaction, enzyme activity, and immunocytochemistry observation. RESULTS: Our results show that HPE combined with DE (HPE:DE) strongly scavenged DPPH radicals and protected proteins against degradation by hydroxyl radical attack. HPE:DE effectively inhibited matrix metalloproteinase-1 expression, protein kinase C alpha expression, and elastinase activity. Furthermore, HPE:DE improved the expression of cognition-related genes (choline acetyltransferase and vesicular acetylcholine transporter). These events may proactively contribute to retard the aging processes and the abrupt physiological changes probably induced by mitochondrial dysfunction with aging. CONCLUSIONS: Based on these findings, we conclude that the combined treatment of HPE:DE may be useful for anti-aging therapy in which the accumulation of oxidative damage is the main driving force.

Fluidized-Bed Granulation of Probiotics-Encapsulated Spray-Dried Skim Milk Powder: Effects of a Fluidizing Aid, Moisture-Activation and Dehydration.

A probiotic powder of poor flowability with high dust content, prepared by spray drying reconstituted skim milk fermented with Lactobacillus rhamnosus GG (LGG), was granulated by fluidized-bed granulation (FBG). The effects of the addition of skim milk powder (SMP) as a fluidizing aid, and of simple moisture-activation with or without dehydration, were investigated with respect to the performance of the FBG process. A fine, poorly fluidizable LGG powder (Geldart Group C) could be fluidized and granulated, with a 4- to 5-fold increase in particle size (d4,3 = 96-141 µm), by mixing with SMP (30-50%), which has larger, fluidizable particles belonging to Geldart Group A. Moisture-activation after the mixing, followed by fluidized-bed dehydration with hot air to remove excess moisture, further improved the FBG; the yield of the granules increased from 42% to 61% and the particle size distribution became much narrower, although the average particle size remained almost the same (d4,3 = 142 µm). These granules showed a popcorn-type structure in scanning electron microscopy images and encapsulated a sufficient level of viable LGG cells (1.6 × 108 CFU g-1). These granules also exhibited much better flowability and dispersibility than the spray-dried LGG powder.

Solid-phase refolding of cyclodextrin glycosyltransferase adsorbed on cation-exchange resin.

Expression with a fusion partner is now a popular scheme to produce a protein of interest because it provides a generic tool for expression and purification. In our previous study, a strong polycationic tail has been harnessed for an efficient purification scheme. Here, the same polycation tail attached to a protein of interest is shown to hold versatility for a solid-phase refolding method that utilizes a charged adsorbent as a supporting material. Cyclodextrin glycosyltransferase (CGTase) fused with 10 lysine residues at the C-terminus (CGTK10ase) retains the ability to bind to a cation exchanger even in a urea-denatured state. When the denatured and adsorbed CGTK10ase is induced to refold, the bound CGTK10ase aggregates little even at a g/L range. The renatured CGTK10ase can also be simply recovered from the solid support by adding high concentration of NaCl. The CGTK10ase refolded on a solid support retains specific enzyme activity virtually identical to that of the native CGTK10ase. Several factors that are important in improving the refolding efficiency are explored. Experimental results indicate that nonspecific electrostatic interactions between the charge of the ion exchanger and the local charge of CGTase other than the polycationic tag should be reduced to obtain higher refolding yield. The solid-phase refolding method utilizing a strong polycationic tag resulted in a remarkable increase in the refolding performance. Taken together with the previous report in which a series of polycations were explored for efficient purification, expression of a target protein fused with a strong polycation provides a straightforward protein preparation scheme.

Characterization of polycationic amino acids fusion systems for ion-exchange purification of cyclodextrin glycosyltransferase from recombinant Escherichia coli.

Fusion proteins with charged polycationic amino acid tails were constructed for the purpose of simple ion-exchange purification with high purity. A number of positively charged lysine and arginine tails were fused to the C-terminus of cyclodextrin glycosyltransferase (CGTase) derived from Bacillus macerans and expressed in Escherichia coli. The ionic binding forces provided by the tails allowed the selective recovery of CGTase from recombinant E. coli cell extracts, while CGTase by itself could not bind to the cation exchanger at neutral pH. The type of amino acids used and the length of the tail directly affected the purification factors. Most intracellular proteins of E. coli adsorbed on the cation exchanger could be removed by washing with 400 mM NaCl solution at pH 7.4, suggesting that a fusion partner suitable for purification purpose should be provided with high binding strength and the maintenance of adsorption by washing with NaCl solution. Among the fusion CGTases constructed, the CGTK10ase containing 10 lysine residues provided sufficiently high binding strength to allow purification to its homogeneity through simple ion-exchange chromatography.

Modulation of guanosine 5'-diphosphate-D-mannose metabolism in recombinant Escherichia coli for production of guanosine 5'-diphosphate-L-fucose.

Guanosine 5'-diphosphate (GDP)-L-fucose, an activated form of a nucleotide sugar, plays an important role in a wide range of biological functions. In this study, the enhancement of GDP-L-fucose production was attempted by supplementation of mannose, which is a potentially better carbon source to be converted into GDP-L-fucose than glucose, and combinatorial overexpression of the genes involved in the biosynthesis of GDP-D-mannose, a precursor of GDP-L-fucose. Supply of a mannose and glucose led to a 1.3-fold-increase in GDP-L-fucose concentration (52.5+/-0.8 mg l(-1)) in a fed-batch fermentation of recombinant E. coli BL21star(DE3) overexpressing the gmd and wcaG genes, compared with the case using glucose as a sole carbon source. A maximum GDP-L-fucose concentration of 170.3+/-2.3 mg l(-1), corresponding to a 4.4-fold enhancement compared with the control strain overexpressing gmd and wcaG genes only, was achieved in a glucose-limited fed-batch fermentation of a recombinant E. coli BL21star(DE3) strain overexpressing manB, manC, gmd and wcaG genes. Further improvement of GDP-L-fucose production was not obtained by additional overexpression of the manA gene.

Leuconostoc citreum HJ-P4 (KACC 91035) regulates immunoglobulin E in an ovalbumin-induced allergy model and induces interleukin-12 through nuclear factor-kappa B and p38/c-Jun N-terminal kinases signaling in macrophages.

Leuconostoc citreum (L. citreum) HJ-P4 (KACC 91035) is one of the major predominant species in kimchi fermentation in Korea. The purpose of the present study was to test the immunomodulatory capacity of L. citreum to modulate the IgE-mediated allergic response and to examine the involvement of NF-kappaB and MAPK in IL-12 production in macrophages. Balb/c mice were sensitized with OVA/alum and oral administration of L. citreum to the mice began before or after the OVA sensitization. Protein and mRNA expression of Th1 cytokines in splenocytes by L. citreum in vitro was measured. The role of NF-kappaB and MAPK such as p38, ERK1/2 and JNK in L. citreum-induced IL-12 was investigated in peritoneal macrophages and RAW264.7 cell lines. L. citreum inhibited the serum levels of total IgE, IgG1 and IgG2a altogether and increased OVA-specific IFN-gamma production in splenocytes from pre- and post-sensitized animals. However, the downregulation of IL-4 and IL-5 production was observed only in the pre-sensitization group. The ability of L. citreum to stimulate IFN-gamma was dependent on its induction of IL-12. NF-kappaB, p38 and JNK were mainly involved in L. citreum-induced IL-12 production. In conclusion, the current study demonstrated that L. citreum is able to regulate serum IgE generation at the induction and effector phases of allergic response through overall control over antibody production and that its involvement of IL-12 production was mediated through NF-kappaB and p38/JNK. Taken together, the use of L. citreum can be useful in preventing the development and progression of IgE production.