• Journal of Life Science
• /
• v.27 no.3
• /
• pp.334-338
• /
• 2017

In this study, the nutritional components of Tenebrio molitor, Protaetia brevitarsis, and Allomyrina dichotoma larvae, which have been registered as novel foods, were analyzed and compared to expand the diversity of selection criteria for edible insects. The contents of crude components, amino acids, fatty acids, and minerals were analyzed. According to the results of comparative analysis of edible insects, crude proteins were abundant in all three kinds of insects. The content of crude fat was the highest in T. molitor, and the content of carbohydrate was the highest in A. dichotoma. When comparing the composition of amino acids, total amino acid content and essential amino acids were the highest in T. molitor larvae. In T. molitor and P. brevitarsis larvae, the compositions of fatty acids were similar, with higher amounts of unsaturated fatty acids than in A. dichotoma. In terms of mineral content, A. dichotoma contained the highest amounts of calcium and iron, whereas P. brevitarsis contained the highest amounts of phosphorus and potassium. With these results, it is expected that edible insects could be selected according to nutritional demand. In addition, multiple combinations of edible insects will offer a richer intake of nutrients.

• Journal of Life Science
• /
• v.27 no.11
• /
• pp.1308-1314
• /
• 2017

The Chinese red-headed centipede Scolopendra subspinipes mutilans, a member of the arthropod class Chilopoda, is a traditional medicine used for the treatment of several allergic diseases, such as atopy. S. subspinipes mutilans samples were collected from different regions of South Korea: Sancheong, Gyeongnam; Yeonggwang, Jeonnam and Jeju-do. The nutritional values of the centipedes were analyzed to extend the species' applications. The crude protein and fat contents of all samples were high and ranged from 54.9-55.8% and from 26.8-30.6%, respectively. Essential amino acids were present; lysine was the most common and accounted for 3.4-3.6% of the essential amino acids. Glutamic acid, which assists in improving concentration, memory and other cognitive abilities, was the most common non-essential amino acid at 6.8-7.1%. It had a similar content percentage in all three regions' samples. Additionally, unsaturated fatty acids were present, and oleic acid, which prevents cancer and cardiac disease, was the most common at 41.3-48.6% of each sample. Mercury, a hazardous substance, was detected at a range of 0.08-0.11 mg/kg in all samples; the amount was lower than the standard food allowance. Additionally, no pathogenic microorganisms, such as Escherichia coli and Salmonella spp., were detected. There were no significant differences between the nutritional factors of the S. subspinipes mutilans samples from the three regions. Based on the nutritional analysis, Chinese red-headed centipedes have the potential to be food and medicinal ingredients due to their proteins, essential amino acids, unsaturated fatty acids and nutritive capacities.

• Journal of Microbiology and Biotechnology
• /
• v.2 no.1
• /
• pp.56-65
• /
• 1992

The complete nucleotide sequence of the Bacillus circulans F-2 RSDA gene, coding for raw starch digesting a-amylase (RSDA), has been determined. The RSDA structure gene consists of an open reading frame of 2508 bp. Six bp upstream of the translational start codon of the RSDA is a typical gram-positive Shine-Dalgarno sequence and the RSDA encodes a preprotein of 836 amino acids with an Mr of 96, 727. The gene was expressed from its own regulatory region in E. coli and two putative consensus promoter sequences were identified upstream of a ribosome binding site and an ATG start codon. Confirmation of the nucleotide sequence was obtained and the signal peptide cleavage site was identified by comparing the predicted amino acid sequence with that derived by N-terminal analysis of the purified RSDA. The deduced N-terminal region of the RSDA conforms to the general pattern for the signal peptides of secreted prokaryotic proteins. The complete amino acid sequence was deduced and homology with other enzymes was compared. The results suggested that the Thr-Ser-rich hinge region and the non-catalytic domain are necessary for efficient adsorption onto raw substrates, and the catalytic domain (60 kDa) is necessary for the hydrolysis of substrates, as suggested in previous studies (8, 9).

• Korean Journal of Food Science and Technology
• /
• v.12 no.4
• /
• pp.263-271
• /
• 1980

Detoxified and deallergenized castor bean protein isolate was prepared from defatted castor bean pomace for use in animal feedstuffs and human foods. Succinylation and acetylation of the ${\varepsilon}-amino$ groups of the protein improved markedly the water solubility of the protein at $pH\;7{\sim}8$. The results of the amino acid analysis of the protein isolate revealed that the sulfur-containing amino acids and L-lysine were limiting amino acids and that succinylation and acetylation caused some little loss of the amino acid content. The L-methionine enriched plastein was synthesized from the protein isolate or the acylated protein isolates and DL-methionine ethyl ester by one step process with papain. By this method the extent of incorporation of L-methionine was about 50%. Pepsin hydrolyzed both unmodified and modified protein isolates at the same rate (about 92%). Tryptic hydrolysis, however, was less for the succinylated protein isolates (about 42%) and less for the acetylated protein isolates (about 26%). The protein efficiency ratio of L-methionine enriched protein isolate (about 2.5 weight %) was 90% that of reference casein. The protein efficiency ratio values of succinylated (88%) and acetylated (84%) protein isolate were 55 and 69% of reference casein, respectively.

• The Korean Journal of Physiology and Pharmacology
• /
• v.16 no.5
• /
• pp.355-360
• /
• 2012

A simple, sensitive and reproducible high-performance liquid chromatography (HPLC) method has been validated for determining concentrations of glutamate, glycine, and alanine in human plasma. Proteins in plasma were precipitated with perchloric acid, followed by derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC). Simultaneous analysis of glutamate, glycine, and alanine is achieved using reversed-phase HPLC conditions and ultraviolet detection. Excellent linearity was observed for these three amino acids over their concentration ranges with correlation coefficients (r)>0.999. The intra- and inter-day precision were below 10%. This method utilizes quality control samples and demonstrates excellent plasma recovery and accuracy. The developed method has been successfully applied to measure plasma glutamate, glycine, and alanine in twenty volunteers.

• Journal of Microbiology and Biotechnology
• /
• v.31 no.8
• /
• pp.1175-1182
• /
• 2021

We investigated the effect of bovine lactoferricin (Lfcin-B), a peptide derived from bovine lactoferrin, on activation of intestinal epithelial cells in IEC-6 intestinal cell, and protection against in vivo rotavirus (RV) infection. Treatment with Lfcin-B significantly enhanced the growth of IEC-6 cells and increased their capacity for attachment and spreading in culture plates. Also, Lfcin-B synergistically augmented the binding of IEC-6 cells to laminin, a component of the extracellular matrix (ECM). In the analysis of the intracellular mechanism related to Lfcin-B-induced activation of IEC-6 cells, this peptide upregulated tyrosine-dependent phosphorylation of focal adhesion kinase (FAK) and paxillin, which are intracellular proteins associated with cell adhesion, spreading, and signal transduction during cell activation. An experiment using synthetic peptides with various sequences of amino acids revealed that a sequence of 9 amino acids (FKCRRWQWR) corresponding to 17-25 of the N-terminus of Lfcin-B is responsible for the epithelial cell activation. In an in vivo experiment, treatment with Lfcin-B one day before RV infection effectively prevented RV-induced diarrhea and significantly reduced RV titers in the bowels of infected mice. These results suggest that Lfcin-B plays meaningful roles in the maintenance and repair of intestinal mucosal tissues, as well as in protecting against intestinal infection by RV. Collectively, Lfcin-B is a promising candidate with potential applications in drugs or functional foods beneficial for intestinal health and mucosal immunity.

• BMB Reports
• /
• v.32 no.1
• /
• pp.82-85
• /
• 1999

The movement protein of cucumber mosaic virus (CMV) is required for cell-to-cell movement of viral RNA. The movement of viral RNA occurs through the plant intercellular connection, the plasmodesmata. The viral movement protein was known to be multi-functional. In this work, a series of deletion mutants of CMV movement protein gene were created to identify the functional domains. The mutated movement proteins were produced as inclusion body in E. coli, and purified and renatured. A polyclonal antibody was raised against the CMV-Kor strain (Korean isolate) movement protein expressed in E. coli. The ability of the truncated proteins to bind to ssRNA was assayed by UV cross-linking and gel retardation analyses. The results indicate that the domain between amino acids 118 and 160 of CMV movement protein is essential for ssRNA binding.

• Korean Journal of Environmental Agriculture
• /
• v.25 no.4
• /
• pp.371-381
• /
• 2006

New proteomic techniques have been pioneered extensively in recent years, enabling the high-throughput and systematic analyses of cellular proteins in combination with bioinformatic tools. Furthermore, the development of such novel proteomic techniques facilitates the elucidation of the functions of proteins under stress or disease conditions, resulting in the discovery of biomarkers for responses to environmental stimuli. The ultimate objective of proteomics is targeted toward the entire proteome of life, subcellular localization biochemical activities, and the regulation thereof. Comprehensive analysis strategies of proteomics can be classified into three categories: (i) protein separation via 2-dimensional gel electrophoresis (2-DE) or liquid chromatography (LC), (ii) protein identification via either Edman sequencing or mass spectrometry (MS), and (iii) proteome quantitation. Currently, MS-based proteomics techniques have shifted from qualitative proteome analysis via 2-DE or 2D-LC coupled with off-line matrix assisted laser desorption ionization (MALDI) and on-line electrospray ionization (ESI) MS, respectively, toward quantitative proteome analysis. In vitro quantitative proteomic techniques include differential gel electrophoresis with fluorescence dyes. protein-labeling tagging with isotope-coded affinity tags, and peptide-labeling tagging with isobaric tags for relative and absolute quantitation. In addition, stable isotope-labeled amino acids can be in vivo labeled into live culture cells via metabolic incorporation. MS-based proteomics techniques extend to the detection of the phosphopeptide mapping of biologically crucial proteins, which ale associated with post-translational modification. These complementary proteomic techniques contribute to our current understanding of the manner in which life responds to differing environment.

• Journal of Microbiology
• /
• v.44 no.5
• /
• pp.515-522
• /
• 2006

A cDNA library of Ganoderma lucidum has been constructed using a Zap Express cloning vector. A glyceraldehyde-3-phosphate dehydrogenase gene (gpd) was isolated from this library by hybridization of the recombinant phage clones with a gpd-specific gene probe generated by PCR. By comparison of the cDNA and the genomic DNA sequences, it was found that the complete nucleotide sequence encodes a putative polypeptide chain of 338 amino acids interrupted by 6 introns. The predicted amino acid sequence of this gene shows a high degree of sequence similarity to the GPD proteins from yeast and filamentous fungi. The promoter region contains a CT-rich stretch, two CAAT boxes, and a consensus TATA box. The possibility of using the gpd promoter in the construction of new transformation vectors is discussed.

• Korean Journal of Food Science and Technology
• /
• v.24 no.1
• /
• pp.1-6
• /
• 1992

Changes in protein distributiun, eletrophoretic patterns and amino acid composition were investigated during germination of malting barley. Fractionation of the protein complex in ungerminated malting barley resulted in a higher hordein fraction but less glutelin fraction of the protein complex in ungerminated malting barley resulted in a higher hordein fraction but less glutelin fraction as compared to germinated malting barley. As germination proceeded, NPN, globulin and glutelin fractions continued to increase, accmpanied by decreases in albumin and hordein fractions. The electrophoretic pattern of malting barley proteins showed three bands (molecular weight range of $15,000{\sim}41,000$ daltons) in albumin fraction, five bands ($19,000{\sim}61,000$ daltons) in globulin fraction, five bands ($18,000{\sim}56,000$ daltons) in hordein fraction and tour bands ($20,000{\sim}47,000$ daltons) in glutelin fraction, exhibiting quantitative changes in each fraction during germination. Amino acid analysis showed that glutamic acid, histidine, aspartic acid, serine, glycine, valine, alanine and leucine were major amino acids of proteins in malting barley grains. Glutamic acid increased slightly, but other amino acids showed no definite trend as germination proceeded.