• Food Science and Preservation
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• v.23 no.4
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• pp.502-509
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• 2016

The seasonal appearance and the chemical composition characteristics of cladode of Opuntia humifusa were investigated in this study. The minor (horizontal) and major (vertical) axes, the width, and weight of O. humifusa cladode were compared for its appearance features. Moisture, crude protein, ash, fat, color, dietary fiber, mineral, and amino acids contents were measured for the comparison of their chemical composition characteristics. The cladode of O. humifusa harvested in summer showed higher values of minor and major axis, width, and weight than those harvested in winter. According to the results of Hunter color index, cladode of O. humifusa harvested in summer showed the highest lightness level (Hunter L value). In the meanwhile, cladode of O. humifusa harvested in spring showed the highest Hunter a (redness) and b (yellowness) values. Cladode of O. humifusa harvested in summer had the lowest crude protein and crude fat contents, while it showed the highest crude ash content. The total contents of moisture and dietary fiber were significantly greater than summer-harvested cladode of O. humifusa followed by spring- and winter-harvested cladode of O. humifusa. The major mineral content of all seasonal cladode of O. humifusa was $Ca^{2+}$. Glutamic acid and aspartic acid were the major amino acids in all seasonal samples. Contrary, the contents of total amino acids and free amino acids were the lowest in summer-harvested cladode of O. humifusa. Taken together, it was concluded that the appearance and chemical quality of cladode of O. humifusa was versatile depending on the harvesting season.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.2
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• pp.144-151
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• 1991

Quality stability and utilization of sardine protein concentrates were investigated. pH, water activity and amino-nitrogen contents of autoclaved and boiled products were little changed during the storage of 60 days. Available lysine contents of the both products at the initial stage of storage were 5.58g/16g-N and 5.69g/16g-N, respectively. But the available lysine contents and digestibility of the both products decreased slightly with increasing of storage time. Lipophilic and hydrophilic brown pigment formation of the both products increased during storage of 60 days, but peroxide value(POV) and thiobarbituric acid(TBA) value decreased. Total amino acid contents of the both products were in the range of $88.99{\~}89.90g/16g-N$, and the predominant ones were glutamic acid, aspartic acid, leucine and lysine. From the sensory scores of model snack, it is concluded that the sardine protein concentrate can be used as a source material for snack.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1015-1021
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• 2007

To expand the use of rainbow trout, the preparation of canned rainbow trout was conducted and the characteristics were also examined. Canned boiled rainbow trout was low in moisture, while high in lipid and ash compared to commercial canned salmon. There was no difference in the protein content between two kinds of canned fish. The contents of free amino acid and total amino acid of canned boiled rainbow trout were 330.9 mg/100 g and 18.2 g/100 g, respectively, and the major amino acids were glutamic acid (68.6 mg/100 g) and anserine (124.1 mg/100 g) in free amino acid and glutamic acid (18.0%), aspartic acid (8.6%), lysine (8.4%) and leucine (8.9%) in total amino acid. The mineral contents of canned boiled rainbow trout were 123.3 mg/100 g for potassium, 271.3 mg/100 g for calcium, 40.3 mg/100 g for magnesium, 2.4 mg/100 g for ferrous and 244.3 mg/100 g for phosphorus. The fatty acid composition of canned boiled rainbow trout was the highest (43.7%) in polyenoic acid, followed by monoenoic acid (28.8%) and saturated acid (27.5%) and their main fatty acids were 16:0 (18.4%), l8:1n-9 (20.6%), l8:2n-6 (17.3%) and 22:6n-3 (12.7%), respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.4
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• pp.342-349
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• 1983

This study was undertaken to ascertain food and nutritional evaluating data on the processing of fermented sea cucumber (Stichopus japonicus) entrails. In the experiment, the crude proteolytic enzyme from the entrails tissue of raw and fermented sea cucumber during the days of ripening was extracted. The optimal activity condition for the crude enzyme and the compositional changes of amino acid of the protein and free amino acid in the raw and fermented sample were also investigated. 1. Less than three kinds of proteolytic enzymes that each enzyme has optimal activity condition at pH 3.1 $50^{\circ}C$(A-enzyme), pH 5.7 $50^{\circ}C$(B-enzyme) and pH 7.7 $45^{\circ}C$(C-enzyme), respectively were believed to be exist in the entrails tissue of sea cucumber. 2. A-enzyme and C-enzyme were strongly inhibited with the increase of the salt concentration, and B-enzyme was activated at the 1% salt concentration and was inhibited above the 5% salt concentration. 3. The result of the effect of several salt ions on the proteolytic activity showed that A-enzyme was slightly inhibited in the presence of all salt ions added, B-enzyme was activated in the presence of the all salt ions except $Cu^{2+}$ and C-enzyme was activated in the presence of $Ca^{2+}$ and $Mn^{2+}$, and inhibited by $Cu^{2+}$, $Co^{2+}$ and $Mg^{2+}$. 4. When the effects of the ripening days on the proteolytic activity of the crude enzymes were analysed, the activity of the A-enzyme was slightly weakened with the lapse of the fermentation days, whereas the B-enzyme was not influenced by the fermentation days. 5. In the analysis of amino acid composition of the protein of the samples, the 8 days fermented sea cucumber entrails showed the diminution of all kinds of amino acid. Apparently diminished amino acids were arginine, alanine, glutamic acid, glycine, serine, valine, threonine and lysine etc., and methionine, histidine and isoleucine were slightly decreased. 6. In the analysis of free amino acid composition of the 8 days fermented sample, glutamic acid, aspartic acid, leucine and lysine were rich, while histidine, methionine, proline and tyrosine were poor. The most of free amino acids were increased during the fermentation procedure and especially in lysine, histidine, threonine, glutamic acid, methionine, valine and leucine.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.604-609
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• 1991

Antibiotic MT-497 was purified from the culture broth of Streptomyces nigr$^1H-NMR$ and composition of amino acids, MT-497 was identified as one of the actinornycin antibiotics containing actinocin chromophore and the peptide with threonine, proline, methyl valine, sarcosine and aspartic acid.

• The KIPS Transactions:PartD
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• v.10D no.2
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• pp.261-266
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• 2003

A protein, which is a linear polymer of amino acids, is one of the most important bio-molecules composing biological structures and regulating bio-chemical reactions. Since the characteristics and functions of proteins are determined by their amino acid sequences in principle, protein sequence determination is the starting point of protein function study. This paper proposes a protein sequence prediction method based on data mining techniques, which can overcome the limitation of previous bio-chemical sequencing methods. After applying multiple proteases to acquire overlapped protein fragments, we can identify candidate fragment sequences by comparing fragment mass values with peptide databases. We propose a method to construct multi-partite graph and search maximal paths to determine the protein sequence by assembling proper candidate sequences. In addition, experimental results based on the SWISS-PROT database showing the validity of the proposed method is presented.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.260-266
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• 2002

In this study, chromosomal DNA fragment related to the regulation of phenol metabolism in Ralstonia eutropha JMP 134 was cloned and sequenced. The result has shown that two open reading frames (ORF1 and ORF2) exist on this regulatory region. ORF1, which initiates from 454 bp downstream of the stop codon of the phenol hydroxylase genes, was found to be composed of 501 amino acids. ORF2, whose start codon is overlapped with the stop codon of ORFl, was found to contain 232 amino acids. The comparison of amino acid sequences with other proteins has revealed that ORF1 belongs to the family of NtrC transcriptional activator, whereas ORF2 shares high homology with the family of GntR protein, which is known to be a negative regulator. ORF1 and ORF2 were designated as a putative positive regulator, phlR2 and a negative regulator phlA, respectively. Possible regulatory mechanisms of phenol metabolism in this strain was discussed.

• Korean Journal of Food Science and Technology
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• v.19 no.2
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• pp.89-96
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• 1987

The denaturation mechanism of the protein during heating of myosin and paramyosin extracted from the ordinary muscle of yellowtail (Seriola qrinqueradits) and the adductor muscle of whelk (Neptunea arthritica cuming) were investigated by analyzing the hydrophobicity, solubility, SH group and protein-protein interaction. The free hydrophobic residue of the two proteins were increased by increase of heating temperature up to $65^{\circ}C$ and then decreased for further temperature raise. The protein-protein interaction was proportional to the increment of the free hydrophobic residue. The aggregation of protein was begun from $65^{\circ}C$ with the decrease of the free hydrophobic residues. The results of Arrhenius equation for the data on proteinprotein interaction showed that the denaturation course was made up with multi-steps in the myosin and two-steps in the paramyosin. The number of free hydrophobic residue and SH group, solubility and protein-protein interaction were significantly differed with the denaturation temperature (p<0.01).

• Journal of Life Science
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• v.11 no.5
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• pp.464-469
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• 2001

A gene, dnaK2, encoding a distinct member of the HSP70 family of molecular chaperones is isolated from the halotolerant cyanobactrium Aphanothece halophytica. The dnak2 gene encodes a molecular wight of 68 kDa polypeptide with predicted 616 amino acid residues. The DnaK2 protein has a structural characteristic of bacterial DnaK homologues and shows high similarity to other HSP70/Dank proteins. The danK2 transcripts are hardly detectable at 28$^{\circ}C$ and strongly induced upon heat stress. It is also found that dnaK2 transcript is increased by high-salinity stress even in the absence of heat stress. These results suggest that the DnaK2 protein plays an important role in protecting A. halophytica against damage caused by salt stress at well as heat stress.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.8-12
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• 2005

Some genes, which are involved in the biosynthesis of polysaccharides, could be found by the genome project of Sphingomonas chungbukensis DJ77. In this study, we identified the complete nucleotide sequence of a gene, encoding the glucosyl-isoprenyl phosphate-transferase, which catalyzes the first step in the biochemical pathway for the synthesis of the sphingan type polysaccharide. This gene, named spsB, is initiated by the ATG codon and terminated by the TGA, and its open reading frame consists of 1392 bp, encoding 463 amino acids. The predicted amino acid sequence of this enzyme indicates $50\%$ similarity to SpsB of Sphingomonas spp S88, also produces sphingan, and $48\%$ to GelB of Sphingomonas paucimobilis ATCC 31461.