• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.482-491
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• 1992

Experiments were conducted to elucidate the effects of pH change and sodium alginate, gum karaya and gum arabic on the foaming properties of soy protein isolate (SPI). The surface tensions of SPI solution (5%) adding to gums at pH 4.0 and 5.0, near the isoelectric point (pH 4.5) were higher than those at pH 7.0 and 8.0. Specific viscosity of the solutions adding to gums (0.1, 0.2 and 0.3%) at pH 7.0 and 8.0 were $3.6{\sim}51.8$ and $4.0{\sim}51.2$, respectively. In cases of addition of sodium alginates specific viscosity were predominantly increased, while those of gum arabic did not almost increase. Addition of gums reduced the overrun, but it stabilized the foams, especially those of sodium alginates (0.2%) increased the foam stability at pH 5.0, 7.0 and 8.0 by 57, 413 and 315%, respectively. Foaming ability, foam stability and heat stability of the foam were significantly (p<0.05) affected by changing pH. There was a tendency to increase the foaming ability according to the decrease of surface tension. Specific viscosity was also important in foam stability and heat stability.

• Pediatric Infection and Vaccine
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• v.6 no.2
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• pp.219-233
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• 1999

Purpose : Respiratory syncytial virus(RSV) is the major cause of lower respiratory tract infection in infants and young children. This study was performed to analyze antigenic and genetic variation of G protein of subgroup A RSV. Methods : One hundred seventy-nine strains isolated at the Seoul National University Children's Hospital over 8 years-period from 1990 through 1998 were analysed for antigenic and genetic variability. Analysis was made by reactivity with monoclonal antibodies raised against RSV, and by restriction mapping and, for selected strains, nucleotide sequencing following amplification of full sequence of G gene by reverse transcription-polymerase chain reaction. Results : Restriction fragment analysis of the amplified G protein gene revealed 23 restriction patterns, 12 of which included more than 2 isolate, and the most frequent genetic type comprised 30% of the strains. Indirect immunofluorescent staining with monoclonal antibodies revealed 6 antigenic types with one predominant pattern accounting for 91% of the total strains. The most frequent antigenic type had 21 restriction patterns, and some viruses with same restiction pattern had different monoclonal antibody reaction pattern. Nucleotide sequence homology of subgroup A was 91~93% between reference(A2, Long) and Korean isolates, 93~99% among Korean isolates. Maximum-parsimony analysis demonstrated that Korean isolates were distinct from reference strains and subgroup A strains were clustered in 4 groups. Conclusion : The restriction analysis pattern of G protein gene identified greater diversity within subgroup A than was seen with the monoclonal analysis and a variety of antigenic and genetic types of RSV are circulating in Korea which are different from reference strains or strains isolated from other countries.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.436-441
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• 1994

To investigate the lowering effects of in vitro enzymatic hydrolysis by the treatment of chymotrypsin, trypsin, pancreatin, or protease from Aspergillus oryzae on the antigenicity of whey protein isolate (WPI) against rabbit anti ${\alpha}-LA$ antiserum, competitive inhibition ELISA (cELISA) and passive cutaneous anaphylaxis (PCA) test using guinea pig were performed. The results of cELISA showed that the monovalent antigenicity of the whey protein hydrolysates (WPH) to the antiserum was decreased to $10^{-2.5}-10^{-5.5}$ and less by the hydrolysis. The monovalent antigenicity of the WPH hydrolyzed by trypsin, or protease from Asp. nryzae was much lowered by the pretreatment of heat denaturation. The antigenicity of the WPH hydrolyzed by chymotrypsin, trypsin, or pancreatin was much lowered by the pretreatment of pepsin. Especially, the antigenicity of TDP (trypic hydrolysate with pretreatment of heat and pepsin) was found almost to be removed. However, there was not consistency between degree of hydrolysis(DH) and the monovalent antigenicity of the WPH. By the heterologous PCA it was found that all of the PGPH lost the polyvalent antigenicity regardless of the pretreatments although WPI and ${\alpha}-LA$ had the positive high antigenicity. The results suggested that the peptides derived from ${\alpha}-LA$ in WPH could bind specific antibodies but they could not induce allergy. Therefore, it was elucidated that the allergenicity of ${\alpha}-LA$ in whey protein could be destroyed easily by the enzymatic hydrolysis.

• Journal of Aquaculture
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• v.21 no.4
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• pp.325-330
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• 2008

Two different Eelwardsiella tarda isolates, KFE and Edk-2, were obtained from Korea and Japan respectively. On the base of the previous results showing higher pathogenicity of E. tarda KFE compared to that of E. tarda Edk-2 isolate, we tried to determine the differences of antigenicities of these two isolates in loach which is one of the important species in freshwater aquaculture in Korea. Concentration of specific antibody in the serum appeared to be much higher in loach immunized with FKC of E. tarda Edk-2 than those found in loach immunized with FKC of E. tarda KFE. Cross-reaction analysis using agglutination test with normal and antigen-absorbed antisera implied the differences epitopes in the antigens of these E. tarda isolates. For the comparison of bactericidal activity of the produced antibody with different antigens, absorption analysis was performed and confirmed the presence of critical epitopes in the FKC of E. tarda KFE strain. The prophylactic agent, polysaccharide-bound protein (PS-K) injected 1 week before the artificial infection with E. tarda KFE isolates decreased the cumulative mortality in loach and would be on effective method to prevent the occurrence of bacterial infection including E. tarda.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.spc1
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• pp.25-45
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• 1996

Soyfoods have potential roles in the prevention and treatment of chronic diseases, most notably cancer, osteoporosis, and heart disease. There is evidence that carcinogenesis are supressed by isolated soybean derived products in vivo such as a protease inhibitor, phytic acid, saponins and isoflavones. It is believed that supplementation of human diets with soybean products markedly reduces human cancer mortality rates. Especially, recent papers recognize the potential benefit of soybean isoflavone components for reducing the risk of various cancers. Isoflavones exhibit a multitude of medicinal effects that influence cell growth and regulation, which may have potential value in the prevention and treatment of cancer. In addition to potential biological effects, soybean isoflavones have the important physiological functions such as the induction of Bradyrizobium japonicum nod genes and the responses of soybean tissues to infection by Phytophthora megasperma as well as biochemical activities such as antifungal and antibacterial actions. Genistin, daidzin, glycitin and their aglycone (genistein, daidzein, glycitein) are the principal isoflavones found in soybean. Malonyl and acetyl forms have also been detected but they are thermally unstable and are usually transformed during the processing in glucoside form. Most soy products, with the exception of soy sauce, alcohol-extracted soy protein concentrate, and soy protein isolate, have total isoflavone concentrations similar to those in the whole soybean. Soybean-containing diets inhibit mammary tumorigenesis in animal models of breast cancer, therefore, it is possible that dietary isoflavones are an important factor accounting for the lower incidence and mortality from breast cancer. Of the total soybean seed isoflavones, $80\~90\%$ were located in cotyledons, with the remainder in the hypocotyls. The hypocotyls had a higher concentrations of isoflavones on a weight basis compared with cotyledons. Isoflavone contents were influenced by genetics, crop years, and growth locations. The effect of crop year had a greater impact on the isoflavone contents than that of location. The climate condition might be the attribution factor to variation in isoflavone contents. Also, while the isoflavone content of cotyledons exhibited large variations in response to high temperature during seed development, hypocotyls showed high concentration in isoflavone content. So, it is concluded that one of the factors affecting isoflavone content in soybean seeds is temperature during seed development. High temperature, especially in maturity stage, causes lower isoflavone content in soybean seed. It is also suggested that there may exist a different mechanism to maintain isoflavone contents between cotyledon and seed hypocotyls. In a conclusion, soy foods may be able to have a significant beneficial impact on public health.

• Research in Plant Disease
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• v.9 no.3
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• pp.107-115
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• 2003

Chinese yam (Dioscorea opposita cv. Jang-Ma) plants showing necrotic mosaic symptom were collected from their growing fields in Andong, Euisong, Gunwi and Daegu, Korea. Direct negative stainning method by electron microscope showed filamentous particles of about 660 nm in length. Immunosorbent electron microscopy (ISEM) revealed filamentous particles of 660nm decorated with antiserum of Chinese yam necrotic mosaic virus (ChYNMV). The virues purified partially were used to isolate viral RNA as template for RT-PCR to amplify about 1.2 kbp of 3'-terminal region (coat protein, 3'-UTR) with ChYNMV specific and oligo-dT primers. Amino acids sequences of amplified CP genes revealed that the viruses shared 97.9% similarity with ChYNMV (AB044386) wh ich was known as the member of Macluravirus. So the viruses from Chinese yam (D. opposita cv. Jang-Ma) plants were identified as ChYNMV. Comparing the CP amion acid sequences of ChYNMV strains with other macluraviruses such as Cardamon mosaic virus (CdMV), Narcissus latent virus (NLV) and Maclura mosaic virus (MacMV) revealed that N-terminal was the most varialbe region and conserved regions were present within the genus Macluravirus.

• Research in Plant Disease
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• v.20 no.4
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• pp.307-313
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• 2014

In May 2013, an angel's trumpet leaves showing mosaic and malformation symptoms were collected from Suwon city, Gyeonggi-do. An analysis of the collected sample by transmission electron microscopy observation showed filamentous rod particles of 720-800 nm in length. On the basis of the these observations, we performed PCR against three reported Potyviruses (Brugmansia mosaic virus, Colombian datura virus and Brugmansia suaveolens mottle virus), and the sample was positive for BruMV. Pathogenicity and host range test of BruMV was determined by mechanical inoculation. Solanaceae (tobacco, tomato and eggplant) and Amaranthaceae (ground cherry) appeared typical virus symptoms. To determine coat protein of this virus, we designed specific primer pairs, and performed PCR amplification, cloning, and sequencing. Phylogenetic analysis showed that BruMV-SW was most closely related to BruMV isolate SK. Comparison of the BruMV-SW coat protein nucleotide sequences showed 92% to 99% identities to the other BruMV isolates.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1223-1229
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• 2009

To construct a new recombinant strain of Bacillus velezensis that has antifungal and insecticidal activity via the expression of the insecticidal Bacillus thuringiensis crystal protein, a B. thuringiensis expression vector (pHT1K-1Ac) was generated that contained the B. thuringiensis cry1Ac gene under the control of its endogenous promoter in a minimal E. coli-B. thuringiensis shuttle vector (pHT1K). This vector was introduced into a B. velezensis isolate that showed high antifungal activities against several plant diseases, including rice blast (Magnaporthe grisea), rice sheath blight (Rhizotonia solani), tomato gray mold (Botrytis cinerea), tomato late blight (Phytophthora infestans), and wheat leaf rust (Puccinia recondita), by electroporation. The recombinant B. velezensis strain was confirmed by PCR using cry1Ac-specific primers. Additionally, the recombinant strain produced a protein approximately 130 kDa in size and parasporal inclusion bodies similar to B. thuringiensis. The in vivo antifungal activity assay demonstrated that the activity of the recombinant B. velezensis strain was maintained at the same level as that of wild-type B. velezensis. Furthermore, it exhibited high insecticidal activity against a lepidopteran pest, Plutella xylostella, although its activity was lower than that of a recombinant B. thuringiensis strain, whereas wild-type B. velezensis strain did not show any insecticidal activity. These results suggest that this recombinant B. velezensis strain can be used to control harmful insect pests and fungal diseases simultaneously in one crop.

• Applied Biological Chemistry
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• v.22 no.1
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• pp.1-9
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• 1979

The physical and chemical properties of ${\gamma}-conglycinin$ of soybean (Glycine max) were investigated. The soybean protein extracted from soybean meal using 0.2M NaCl solution at pH 4.5 was passed through a Sephadex G-150 column to isolate 7S globulin. ${\gamma}$-Conglycinin was isolated and purified from the 7S globulin with a DEAE Sephadex A-50 column chromatography. The protein preparation was pure on immunoelectrophoresis, polyacrylamide gel electrophoresis and gel isoelectric fouling. It had an isoelectric point at pH 5.4 and contained 16.12% nitrogen, 4.18% mannose and 1.21% glucosamine. Amino acid composition, in general, shaved that ${\gamma}-conglycinin$ contained higher contents of lysine, dicarboxylic acids and ammonia nitrogen, and lower contents of sulfur-containing amino acids and tryptophan. The subunits of ${\gamma}-conglycinin$ were distributed in the range of pH 4.6-5.5. The subunits located in the pH region of 4.6-5.0 and 5.0-5.5 were glycopeptides (molecular weight of 38,000) and simple peptide (MW of 32,000), respectively.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.5
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• pp.698-713
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• 1999

Adherence of Candida albicans(C. albicans) to the surface of a denture is believed to be an initial and essential step in the formation of denture-induced stematitis. Previous studies have provided enormous infomation on the relationship between composition of palatine gland/parotid saliva and upper denture stomatitis. Relatively little information is available on the correlation between lower denture stomatitis and sublingual-submandibular ( SLSM ) saliva. The plaque samples were collected from the two sites($100mm^2$) on the inner surface of lower partial denture corresponding to the stematitis and healthy region of the lower partial dentures of 12 denture stomatitis patients and 6 nor-mal persons who wore lower partial dentures. The samples were plated to isolate C. albicans on a selective Saboraud's dextrose agar plate and the isolates were identified by germ tube test and gram staining. The subjects were divided into group I (stomatitis with C. albican), group II (lesion without C. albicans), group III (no lesion but C. albicans), and group IV (normal and healthy denture wearer). Individual SLSM saliva($20{\mu}g$ of protein) was analyzed by SDS-PAGE (SDS -poly-acrylamide gel electrophoresis) with Coomassie brilliant blue and PAS(Periodic Acid Schinff) stain-ing. The salivary proteins separated in the polyacryamide gels were subjected to immunoblot anaysis using anti-lactoferrin, anti-sIgA, and anti-secretory component of sIgA. In this study using custom made acrylic denture resin beads(5mm in diameter) coated with stimulated individual SLSM saliva, the binding ability of individual C. albicans strains to the beads was observed. Levels of C, albicans adhered to the acrylic resin beads were determined by measuring the optical density of the bound C. albicans to the beads at 580nm. The results showed that a higher number of C. albicans was observed in the lesion site than healthy site. The saliva of group I contained more high molecular weight glycoprotein(mucin, MGI) as compared to group II, III and IV. And lactoferrin and sIgA affected to the binding ability of C. albicans to acylic resin beads. Binding ability of individual C. albicans to the acrylic resin coated with respective individual saliva was found to be greater in group I than the other 3 groups. And when bound cells of C. albicans isolated from individual subject #2 to the saliva coated beads were used binding ability of subject #2 saliva coated beads was founed to be greater than the other sutjects. These results suggested that denture induced stomatitis is related to individual patient's salivary protein composition, especially MG-1. Future studies will be directed toward saliva exam-ination of patients who have general disease and analysis of pellicles formed on prosthesis with respect to oral disease.