• Journal of Dairy Science and Biotechnology
• /
• v.35 no.2
• /
• pp.93-97
• /
• 2017

Linum usitatissimum L. (flaxseed) is emerging as an important functional food ingredient because of its rich contents, namely, ${\alpha}$-linolenic acid (ALA, omega-3 fatty acid), lignans, and fiber, which are potentially beneficial for human health. Furthermore, flax or flaxseed oil has also been incorporated as a functional food ingredient into various foods such as milk, dairy products, and meat products. Flaxseed is known to possess antimicrobial activity in vitro and in vivo, but its growth-stimulating effect on lactic acid bacteria is not clear. Hence, the objective of this study was to determine whether crude flaxseed extract stimulated the growth kefir-isolated lactic acid bacteria in vitro. The result of this study showed that Lactobacillus kefiranofaciens DN1, Lactobacillus brevis KCTC3102, Lactobacillus bulgaricus KCTC3635, and Lactobacillus plantarum KCTC3105 treated with $100{\mu}L$ of crude flaxseed extract showed significantly higher growth than the control treated with $100{\mu}L$ of water (p<0.05). Based on the results of this study, crude flaxseed extract could be used as a growth stimulator for lactic acid bacteria in various food applications, including production of milk and dairy products.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.5
• /
• pp.741-746
• /
• 2005

To investigate the basic information and the possibility of ACE-inhibitory peptides for antihypertension materials, goat's caisin (CN) was hydrolyzed by various proteolytic enzymes and ACE-inhibitory peptides were separated and purified. ACE-inhibition ratios of enzymatic hydrolysates of goat's CN and various characteristics of ACE-inhibitory peptides were determined. ACE-inhibition ratios of goat's CN hydrolysates were shown the highest with 87.84% by pepsin for 48 h. By Sephadex G-25 gel chromatograms, Fraction 3 from goat's CN hydrolysates by pepsin for 48 h was confirmed the highest ACE-inhibition activity. Fraction 3 g and Fraction 3 gh from peptic hydrolysates by RP-HPLC to first and second purification were the highest in ACE-inhibition activity, respectively. The most abundant amino acid was leucine (18.83%) in Fraction 3 gh of ACE-inhibitory peptides after second purification. Amino acid sequence analysis of Fraction 3 gh of ACE-inhibitory peptides was shown that the Ala-Tyr-Phe-Tyr, Pro-Tyr-Tyr and Tyr-Leu. IC$_{50}$ calibrated in peptic hydrolysates at 48 h, Fraction 3, Fraction 3 g and Fraction 3 gh from goat's CN hydrolysates by pepsin for 48 h were 29.89, 3.07, 1.85 and 0.87 g/ml, respectively. Based on the results of this experiment, goat's CN hydrolysates by pepsin were shown to have ACE-inhibitory activity.

• Asian-Australasian Journal of Animal Sciences
• /
• v.26 no.5
• /
• pp.625-629
• /
• 2013

The melanocortin 1 receptor (MC1R) gene is related to the plumage color variations in chicken. Initially, the MC1R gene from 30 individuals was sequenced and nine polymorphisms were obtained. Of these, three and six single nucleotide polymorphisms (SNPs) were confirmed as synonymous and nonsynonymous mutations, respectively. Among these, three selected SNPs were genotyped using the restriction fragment length polymorphism (RFLP) method in 150 individuals from five chicken breeds, which identified the plumage color responding alleles. The neighbor-joining phylogenetic tree using MC1R gene sequences indicated three well-differentiated different plumage pigmentations (eumelanin, pheomelanin and albino). Also, the genotype analyses indicated that the TT, AA and GG genotypes corresponded to the eumelanin, pheomelanin and albino plumage pigmentations at nucleotide positions 69, 376 and 427, respectively. In contrast, high allele frequencies with T, A and G alleles corresponded to black, red/yellow and white plumage color in 69, 376 and 427 nucleotide positions, respectively. Also, amino acids changes at position Asn23Asn, Val126Ile and Thr143Ala were observed in melanin synthesis with identified possible alleles, respectively. In addition, high haplotype frequencies in TGA, CGG and CAA haplotypes were well discriminated based on the plumage pigmentation in chicken breeds. The results obtained in this study can be used for designing proper breeding and conservation strategies for the Korean native chicken breeds, as well as for the developing breed identification markers in chicken.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.10
• /
• pp.1464-1470
• /
• 2017

Objective: This study investigated the effect of fermented biogas residue (FBR) of wheat on the performance, serum biochemical parameters, and meat quality in pigs. Methods: We selected 128 pigs (the mean initial body weight was $40.24{\pm}3.08kg$) and randomly allocated them to 4 groups (1 control group and 3 treatment groups) with 4 replicates per group and 8 pigs per pen in a randomized complete block design based on initial body weight and sex. The control group received a corn-soybean meal-based diet, the treatment group fed diets containing 5%, 10%, and 15% FBR, respectively (abbreviated as FBR5, FBR10, and FBR15, respectively). Every group received equivalent-energy and nitrogen diets. The test lasted 60 days and was divided into early and late stages. Blood and carcass samples were obtained on 60 d. Meat quality was collected from two pigs per pen. Results: During the late stage, the average daily feed intake and average daily gain of the treatment groups was greater than that of the control group (p<0.05). During the entire experiment, the average daily gain of the treatment groups was higher than that of the control group (p<0.05). Fermented biomass residue did not significantly affect serum biochemical parameters or meat quality, but did affect amino acid profiles in pork. The contents of Asp, Arg, Tyr, Phe, Leu, Thr, Ser, Lys, Pro, Ala, essential amino acids, non-essential amino acids, and total amino acids in pork of FBR5 and FBR10 were greater than those of the control group (p<0.05). Conclusion: These combined results suggest that feeding FBR could increase the average daily gain and average daily feed intake in pigs and the content of several flavor-promoting amino acids.

• Asian-Australasian Journal of Animal Sciences
• /
• v.31 no.1
• /
• pp.47-53
• /
• 2018

Objective: The objective of this experiment was to investigate the effects of heat stress on milk protein and blood amino acid profile in dairy cows. Methods: Twelve dairy cows with the similar parity, days in milk and milk yield were randomly divided into two groups with six cows raised in summer and others in autumn, respectively. Constant managerial conditions and diets were maintained during the experiment. Measurements and samples for heat stress and no heat stress were obtained according to the physical alterations of the temperature-humidity index. Results: Results showed that heat stress significantly reduced the milk protein content (p<0.05). Heat stress tended to decrease milk yield (p = 0.09). Furthermore, heat stress decreased dry matter intake, the concentration of blood glucose and insulin, and glutathione peroxidase activity, while increased levels of non-esterified fatty acid and malondialdehyde (p<0.05). Additionally, the concentrations of blood Thr involved in immune response were increased under heat stress (p<0.05). The concentration of blood Ala, Glu, Asp, and Gly, associated with gluconeogenesis, were also increased under heat stress (p<0.05). However, the concentration of blood Lys that promotes milk protein synthesis was decreased under heat stress (p<0.05). Conclusion: In conclusion, this study revealed that more amino acids were required for maintenance but not for milk protein synthesis under heat stress, and the decreased availability of amino acids for milk protein synthesis may be attributed to competition of immune response and gluconeogenesis.

• Reproductive and Developmental Biology
• /
• v.40 no.2
• /
• pp.15-22
• /
• 2016

As a one of unsaturated fatty acid, polyunsaturated fatty acids (PUFAs) have multiple actions: as precursor of prostaglandins (PGs), steroid hormone synthesis and energy production in animal reproduction. PUFAs, which include omega-3 (n-3) and omega-6 (n-6), are derived from the diet and changed by diet, species, breed and season. The plasma membrane of spermatozoa in mammals contain various PUFAs. These composition of PUFAs regulate the membrane fluidity and cause lipid peroxidation via generation of reactive oxygen species (ROS). Induced lipid peroxidation by ROS decreased viability and motility of spermatozoa, and it is reduced by addition of antioxidant and low concentration of PUFAs. Because oocytes of animal have a high lipid components, process of oocyte maturation and embryo development are influenced by PUFAs. In in vitro study, oocyte maturation, embryo development, intracellular cAMP and MAPK activity were increased by treatment of n-3 ${\alpha}$-linolenic acid (ALA) during maturation, whereas n-6 linoleic acid (LA) negatively influenced. Also, inhibition of fatty acid metabolism in oocyte influenced blastocyst formation of cattle. PGs are synthesized from PUFAs and various PUFAs influence PGs via regulation of PG-endoperoxide synthase (PTGS). Steroid hormone synthesis from cholesterol is regulated by expression of steroid acute regulator (StAR) protein and mRNA. Exogenous n-3 and n-6 PUFAs altered sex hormone in animal through stimulate or inhibit StAR activity. Because PUFAs altered PG and steroid hormone synthesis, follicular development was influenced by PUFAs. This effect of unsaturated fatty acid could provide information for improvement of reproductive ability in animals.

• Microbiology and Biotechnology Letters
• /
• v.22 no.5
• /
• pp.507-514
• /
• 1994

Acetyl xylan esterase was produced by E. coli HB101 harboring a recombinant plasmid pKMG6 which contained the estI gene of Bacillus stearothermophilus. The maximum production was observed when the E. coli strain was grown at 37$\circC for 12 hours in the medium containing 0.5% acetyl xylan, 1.0% tryptons, 1.0% sodium chloride, and 0.5% yeast extract. The esterase produced was purified to homogeneity using a combination of ammonium sulfate fractionation, DEAE Sepharose CL-6B ion exchange chromatography and Sephacryl S-200 gel filtration. The native enzyme had an apparent molecular mass of 60 kd and was composed of two identical subunits of 29 kd. The N-terminal amino acid sequence of the polypeptide was Ala-X-Leu-Gln- Ile-Gln-Phe-X-X-Gln. The acetyl esterase displayed a pH optimum of 6.5 and a temperature opti- mum of 45$\circC. The heavy metal ions such as Ag$^{++}$, Hg$^{++}$ and Cu$^{++}$ inhibited nearly completely the activity of the esterase, and no specific metal ion was found to be required for the enzyme activity. The enzyme readily cleaved MAS, $\beta$-D-glucose pentaacetate, $\alpha$-naphthyl acetate, $\rho$-nitrophenyl acetate as well as acetyl xylan, but had no activity on $\rho$-nitrophenyl propionate, $\beta$-nitrophenyl butyrate or $\beta$-nitrophenyl valerate. The Km and Vmax values for MAS were 2.87 mM and 11.55 $\mu$mole/min, respectively. Synergistic behavior was demonstrated with a combination of xylanase and esterase from B. stearothermophilus in hydrolyzing acetyl xylan.

• Journal of Microbiology and Biotechnology
• /
• v.24 no.4
• /
• pp.483-488
• /
• 2014

In order to improve the expression of heat-resistant xylanase XYNB from Aspergillus niger SCTCC 400264, XynB has been cloned into Pichia pastoris secretary vector pPIC9K. The XynB production of recombinant P. pastoris was four times that of E. coli, and the $V_{max}$ and specific activity of XynB reached $2,547.7{\mu}mol/mg$ and 4,757 U/mg, respectively. XynB still had 74% residual enzyme activity after 30 min of heat treatment at $80^{\circ}C$. From the van der Waals force analysis of XYNB (ACN89393 and AAS67299), there is one more oxygen radical in AAS67299 in their catalytic site, indicating that the local cavity is much more free, and it is more optimal for substrate binding, affinity reaction, and proton transfer, etc, and eventually increasing enzyme activity. The H-bonds analysis of XYNB indicated that there are two more H-bonds in the 33rd Ser of XYNB (AAS67299) than in the 33rd Ala(ACN89393 ), and two H-bonds between Ser70 and Asp67.

• Journal of Chitin and Chitosan
• /
• v.23 no.4
• /
• pp.220-227
• /
• 2018

Amyloid plaque is a product of aggregation of ${\beta}$-amyloid peptide ($A{\beta}$) and is an important factor in the pathogenesis of Alzheimer's Disease (AD). $A{\beta}$ is a major component of amyloid plaque and vascular deposits in the AD brain. The enzyme ${\beta}$-secretase is required for the production of $A{\beta}$; thus, prevention of the formation of $A{\beta}$ through the inhibition of ${\beta}$-secretase is a major focus in the study of the treatment of AD. In this study, we investigated ${\beta}$-secretase inhibitory activity of an Arctoscopus japonicus peptide. An Alcalase hydrolysate had the highest ${\beta}$-secretase inhibitory activity. A ${\beta}$-secretase inhibitory activity peptide was separated using ion exchange column chromatography (carboxy-methyl: CM, quaternary methyl ammonium: QMA) and reverse phase high performance liquid chromatography (RP-HPLC) on a C18 column. The $IC_{50}$ value of the purified peptide was $248.2{\pm}1.73{\mu}g/mL$. The ${\beta}$-secretase inhibitory peptide was identified as a six amino acid residue of Gly-Pro-Val-Gly-Ala-Pro (MW: 497.27 Da). In cell viability experiments, the final purified fraction, the carboxy-methyl ion exchange column fraction (CM-F1) showed no significant cytotoxic effect in SH-SY5Y cells at concentrations below $100{\mu}g/mL$ in 24 h. The results of this study suggest that peptides separated from Arctoscopus japonicus may be beneficial as ${\beta}$-secretase inhibitor compounds in functional foods.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.6
• /
• pp.765-773
• /
• 2009

Sterol regulatory element binding factor 1 (SREBF1) and fatty acid synthase (FASN) genes play an important role in the biosynthesis of fatty acids and cholesterol, and in lipid metabolism. This study used polymorphisms in the intron 5 of bovine SREBF1 and in the thioesterase (TE) domain of FASN genes to evaluate their associations with beef fatty acid composition. A previously identified 84-bp indel (L: insertion/long type and S: deletion/short type) of the SREBF1 gene in Korean cattle had significant associations with the concentration of stearic (C18:0), linoleic (C18:2) and polyunsaturated fatty acids (PUFA). The stearic acid concentration was 6.30% lower in the SS than the LL genotype (p<0.05), but the linoleic and PUFA contents were 11.06% and 12.20% higher in SS compared to LL (p<0.05). Based on the sequence analysis, five single nucleotide polymorphisms (SNPs) g.17924G>A, g.18043C>T, g.18440G>A, g.18529G>A and g.18663C>T in the TE domain of the FASN gene were identified among the different cattle breeds studied. Among these, only g.17924 G>A and g.18663C>T SNPs were segregating in the Hanwoo population. The g.17924G>A SNP is a non-synonymous mutation (thr2264ala) and was significantly associated with the contents of palmitic (C16:0) and oleic acid (C18:1). The oleic acid concentration was 3.18% and 2.79% higher in Hanwoo with the GG genotype than the AA and AG genotypes, respectively (p<0.05), whereas the GG genotype had 3.8% and 4.01% lower palmitic acid than in those cattle with genotype AA and AG, respectively (p<0.05). Tissue expression data showed that SREBFI and FASN genes were expressed in a variety of tissues though they were expressed preferentially in different muscle tissues. In conclusion, the 84-bp indel of SREBF1 and g.17924G>A SNP of the FASN gene can be used as DNA markers to select Hanwoo breeding stock for fatty acid composition.