• Food Science and Biotechnology
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• v.17 no.4
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• pp.761-765
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• 2008

Bacillus cereus causes two different types of food poisoning syndromes: diarrhea and emesis. The diarrheal syndrome is attributed to various enterotoxins, including nonhemolytic enterotoxin, hemolytic enterotoxin, and enterotoxin-T, whereas the emetic syndrome is caused by the dodecadepsipeptide toxin cereulide. A multiplex polymerase chain reaction (PCR) assay was developed to rapidly detect and identify B. cereus strains. Three primer pairs specific to regions within genes encoding nonhemolytic enterotoxin (nheA), molecular chaperonin (groEL), and cereulide synthetase (ces) were used to identify and differentiate between the enterotoxin-producing and emetic toxin-producing B. cereus strains. The cereulide-producing emetic B. cereus showed 3 PCR products of 325, 405, and 685 bp for the groEL, ces, and nheA genes, respectively, whereas the enterotoxin-producing B. cereus showed 2 PCR products without a ces gene specific DNA fragment. Specific amplifications and differentiations by multiplex PCR assay were obtained using 62 B. cereus strains and 13 strains' of other bacterial species. The detection limit of this assay for enterotoxin-producing strain and emetic toxin-producing strain from pure cultures were $2.4{\times}10^1$ and $6.0{\times}10^2\;CFU/tube$, respectively. These results suggest that our multiplex PCR method may be useful for the rapid detection and differentiation of B. cereus strains in foods.

• The Journal of the Korean Society for Microbiology
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• v.8 no.1
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• pp.27-32
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• 1973

Listeria monocytogenes human infection is a relatively rare disease which usually is meningitis in newborn babies. The organism was isolated from blood cultures of a 52 year old female patient with meningitis. It was considered that the underlying disease, i.e. S.L.E., and the steroid therapy which the patient had been receiving played some role for the Listeria infection. The isolate was showing characteristics of L. monocytogenes, i.e. diphtheroid like morphology, motility with four peritrichous flagella, hemolytic small colonies on blood agar, growth in the presence of 7.5% salt and at 4 C, and inducing monocytosis in an experimentally infected rabbit. Serologically the organism was identified as L. monocytogenes 4b. The isolate was showing susceptibility to many antibiotics tested including ampicillin, penicillin and tetracycline which were the recommended drugs of choice for the treatment of Listeriosis. It is the general opinion that Listeriosis is not so rare as literatures are showing. It is considered that some of the isolate of the organism from clinical specimens are mistakenly discarded due to the fact that the organism shows diphtheroid like morphology and that not many laboratories are able to recognize the organism. Literatures are seen which emphasize more careful examination of gram positive bacilli with diphtheroid like morphology especially when they are isolated from blood or from spinal fluid of patient.

• Journal of fish pathology
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• v.22 no.2
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• pp.115-124
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• 2009

Photobacterium damselae subsp. damselae and 4 Vibrio spp, V. anguillarum, V. splendidus, V. harveyi and V. ordalii, were isolated from the diseased olive flounders, Paralichthys olivaceus. The pathogenicity of the isolates were compared to mortality, blood biochemical contents, such as alanineaminotransferase(ALT), aspatate aminotransferase(AST), and cortisol level, and non-specific immune responses, nitroblue tetrazolium (NBT) reduction of macrophages and lysozyme activities of serum. The mortalities and levels of ALT, AST and cortisol of fishes infected with P. damselae were higher than those of others but significantly low in non-specific immune responses, NBT and lysozyme activities. These results suggest that P. damsela might produce damselysin having high hemolytic and phospholipase activities, correlated with the pathogenicity. P. damsela could also make an obstruction of internal organs, following increasing in the level of ALT and AST, and depression in host immunity caused by induced high levels of cortisol.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.303-314
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• 1992

Experiments were performed on mice to investigate the effect of methionine diets (MET) on the immunotoxicity of ethanol. ICR female mice were divided into 5 groups, Met (Basal (B)+0.19% methionine(M), B+1.71% M and B+5.13%W) and ethanol(4%) were administered ad libitum for 21 days. The mice were evaluated for changes in immune status as measured by antibody titer, Arthus reaction, delayed type hypersensitivity (DTH), rosette forming cell(RFC) and plaque forming cell (PFC) to sheep red blood cells (S-RBC). To investigate the change of the non-specific immune response, the number of leukocytes in peripheral blood and phagocyte activity were measured. The results were summarized as follows: (1) The weight ratios of spleen and thymus to body weight were significantly increased by the B+0.19% M, B+0.57% M and B+1.71% M groups in comparison with control group(B), but B+5.13% M group was significantly decreased. (2) Humoral immune responses were significantly increased by the B+0.19% M and B+0.57% M groups in comparison with control group, but B+5.13% M group was significantly decreased. (3) Cellular immune responses were significantly decreased by the B+1.71% M and B+5.13% M groups in comparison with control group. (4) Phagocyte activities were significantly increased by the B+0.19% M, B+0.57% M and B+1.71% M groups in comparison with control groups, but B+5.13% M group was significantly decreased. (5) The number of circulating leukocyte was significantly increased in the B+0.19% M and B+0.57% M groups in comparison with control group, but B+5.13% M group was significantly decreased.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.291-302
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• 1992

Effects of Zinc chloride on the immune responses were studied in ICR mice. ICR male mice were divided into 5 groups(10 mice/group) and Zinc chloride at doses of 0.3, 1.2, 4.8 and 19.2 mg/kg were orally administered to ICR male mice once a day for three weeks. Mice were sensitized and challenged with sheep red blood cells(S-RBC). The results of this study were summarized as follows; (1) Zinc chloride significantly increased the body weight rate, the weight ratios of spleen and thymus to body weight and the number of circulating leukocyte, but significantly decreased them at the high dose of it, and increased dose-dependently the weight ratio of liver to body weight. (2) Zinc chloride significantly increased hemagglutination titer, Arthus reaction and plaque forming cell related to humoral immunity, but significantly decreased them at the high dose of it. (3) Zinc chloride significantly increased delayed-type hypersensitivity reaction and rosette forming cell related to cellular immunity, but significantly decreased them at the high dose of it. (4) Zinc choride significantly enhanced phagocytic activity, but significantly decreased according to the increase of its dose. These results suggest that high dose of zinc chloride decreased humoral, cellular and non-specific immune responses.

• Archives of Pharmacal Research
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• v.18 no.2
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• pp.84-89
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• 1995

The complexation and physical characteristics of egg phosphatidylcholine (PC) liposome containing amphotericin B(AmB) were investigated through circular dichrosim(CD) spectra, the size distribution, the turbidity change, and the calcein release. CD spectra of AmB-containing egg PC mxture exhibited a positive peak around 330 nm indicative of complexation of AmB and four negative peaks. The positive peak increased up to $2.2{\;}millidegree/{\mu}g$ AmB as AmB contents increased up to 12% (w/w), suggesting that AmB-phospholipid complexation was promoted by the antibiotics. The effective diameter of liposomesa by dynamic light scattering decreased from 450 nm to 220 nm as the amount of AmB in liposomes increased from o to 30% (w/w). The complexation may be responsible for the reduction in size. On the other hand, at around 1 mN deoxycholate (DOC), the reltive turbidities of 5 and 10% (w/w) AmB-containing liposome suspension were less than 1 probably due to the soblubilization of the complex, while those of pure PC liposome suspension were larger than 1 at the same concentration. Deoxycholate-induced release of liposomes, indicating the intercalation of the drug into the bilayers. Therefore, it is concluded that in AmB/eggPC/water system, AmB-phospholipid complexcoexists with AmB-containing liposomes.

• Annals of Laboratory Medicine
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• v.38 no.6
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• pp.599-603
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• 2018

Frequencies of red blood cell (RBC) blood group antigens differ by ethnicity. Since the number of immigrants is increasing in Korea, RBC antigens should be assessed in children/youths with parents of different ethnicities to ensure safe transfusions. We investigated the frequency of RBC antigens, except for ABO and RhD, in 382 children and youths with parents having Korean and non-Korean ethnicities. Subjects were divided into those with ethnically Korean parents (Korean group; N=252) and those with at least one parent of non-Korean ethnicity (non-Korean group; N=130). The 37 RBC antigens were genotyped using the ID CORE XT system (Progenika Biopharma-Grifols, Bizkaia, Spain). The frequencies of the Rh (E, C, e, $hr^S$, and $hr^B$), Duffy ($Fy^a$), MNS ($Mi^a$), and Cartwright ($Yt^b$) antigens differed significantly between the two groups. Eight and 11 subjects in the Korean and non-Korean groups, respectively, exhibited negative expression of high-frequency antigens, whereas 14 subjects in the non-Korean group showed positive expression of low-frequency antigens. The frequency of RBC antigens has altered alongside demographic changes in Korea and might lead to changes in distribution of RBC antibodies that cause acute or delayed hemolytic transfusion reaction.

• Parasites, Hosts and Diseases
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• v.59 no.5
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• pp.447-455
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• 2021

Vivax malaria incidence in Korea is now decreased and showing a low plateau. Nowadays, vivax malaria in Korea is expected to be successfully eliminated with anti-malaria chemotherapy, primaquine, and vector control. The glucose-6-phosphate dehydrogenase (G6PD) deficiency is associated with potential hemolytic anemia after primaquine administration. This inborn disorder has a pivotal polymorphism with genetic variants and is the most prevalent X-chromosome-linked disorder. The prevalence of G6PD deficiency was previously reported negligible in Korea. As the population of multicultural families pertaining marriage immigrants and their adolescents increases, it is necessary to check G6PD deficiency for them prior to primaquine treatment for vivax malaria. The prevalence of G6PD variants and G6PD deficiency in multicultural families was performed in 7 counties and 2 cities of Jeollanam-do (Province), Gyeonggi-do, and Gangwon-do. A total of 733 blood samples of multicultural family participants were subjected to test the phenotypic and genetic G6PD deficiency status using G6PD enzyme activity quantitation kit and PCR-based G6PD genotyping kit. The G6PD phenotypic deficiency was observed in 7.8% of male adolescent participants and 3.2% of materfamilias population. Based on the PCR-based genotyping, we observed total 35 participants carrying the mutated alleles. It is proposed that primaquine prescription should seriously be considered prior to malaria treatment.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.369-374
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• 2021

Brown blotch disease of oyster mushrooms is caused by tolaasin and its analog peptide toxins which are produced by Pseudomonas tolaasii. Tolaasin peptides form pores in the plasma membrane and destroy the fruiting body structure of mushroom. Lysis of red blood cells, hemolysis, can be occurred by cytotoxic activity of tolaasin. The hemolytic activity of tolaasin is inhibited by metal ions, such as Zn²⁺ and Ni²⁺. When Gadolinium ion was added, a biphasic effect was observed on tolaasin-induced hemolysis, an increase in hemolysis at submillimolar concentrations and an inhibition at millimolar concentrations. The mechanism of gadolinium ion-induced inhibition of tolaasin activity may not be similar to those of the inhibitions by other metal ions. Since gadolinium ion has been reported to change a lateral pressure of lipid membrane by binding to the negative charges of membrane lipids, it may not directly work on the tolaasin channel gating, but rather decrease the stability of tolaasin channel by increasing firmness of membrane.

• Journal of Applied Biological Chemistry
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• v.62 no.3
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• pp.257-264
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• 2019

Rice bran is considered a natural source of antioxidants. In this study, rice bran was fermented with lactic acid bacteria to increase its antioxidant activity. Four strains isolated from fermented food, Lactobacillus plantarum MJM60383, Lactococcus lactis subsp. lactis MJM60392, Lactobacillus fermentum MJM60393, and Lactobacillus paracasei MJM60396, were confirmed as safe through stability tests such as safety assessment for biogenic amine production, hemolytic activity, and mucin degradation, and showed high reducing capacity. The antioxidant activity of rice bran fermentation altered by these strains was evaluated using several methods including measurement of $Fe^{2+}$ chelating activity and scavenging activity by 1,1-diphenyl-2-picryl-hydrazil (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and nitric oxide assays. In this study, the total phenolic content and ${\gamma}$-oryzanol were evaluated by high-performance liquid chromatography. Compared to non-fermented rice bran and a commercial product, rice bran fermented with Lactococcus lactis subsp. lactis MJM60392 showed the highest phenolic content (844.13 mg GAE/g). Moreover, the content of ferulic acids, ${\rho}$-coumaric acid, and ${\gamma}$-oryzanol in rice bran increased after fermentation with L. lactis subsp. lactis MJM60392 and L. fermentum MJM60393 compared to other samples. Indeed, the DPPH radical scavenging activity and NO scavenging activity were also found to be high in these fermented rice brans. These results indicated that fermentation with lactic acid bacteria increases the active compound levels and the potent antioxidant activities of rice bran.