• Proceedings of the Botanical Society of Korea Conference
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• pp.88-88
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• 2002

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.924-929
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• 2005

Boiled-water extracts from 101 Korean medicinal plants were tested in vitro for their inhibitory activity against influenza virus type A by means of a modified hemagglutination inhibition test. Thirteen of the 101 extracts exhibited strong anti-influenza virus type A activity at concentrations of less than $780\;{\mu}g/ml$. Out of the above 13 extracts, MW-40 (Chaenomeles speciosa), MW-88 (Citrus junos), and MW-100 (Zingiber officinale) exhibited marked antiviral activity in the concentration range of $0.195\;{\mu}g/ml$ to 100 mg/ml, $0.0487\;{\mu}g/ml$ to 100 mg/ml, and $0.0487\;{\mu}g/ml$ to 100 mg/ml, respectively. The extracts MW-88 and MW-100 were not cytotoxic to red blood cells, whereas MW-40 showed very weak cytotoxicity in the concentration range of 50 mg/ml to 100 mg/ml. Therefore, the present results demonstrate that boiled water extracts of 2 Korean medicinal plants, MW-88 and MW-100, have strong anti-influenza virus type A activity and no cytotoxic effects, and they may inhibit attachment of the virus to the cell and may be used for prophylaxis.

• Korean Journal of Pharmacognosy
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• v.18 no.4
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• pp.216-232
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• 1987

In order to investigate the preventive and therapeutic effects of Herba Houttuyniae, experimental studies on the immune response and histological findings were undertaken. The results of these studies were summarized as follows; Delayed type hypersensitivity and rosette formation rate were significantly increased compared with control group. Hemagglutination, hemolysin titer and NK cell activity were variable, not significantly against the control group. When observed on lung tissue recovery; experimental groups were shown to be significantly recovered as compared with the control group. From these results, it is suggested that Houttuyniae Herba promotes immune response and reduces the recovery time of pneumonitis and lung abscess from the histological viewpoint.

• Korean Journal of Veterinary Research
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• v.20 no.2
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• pp.99-104
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• 1980

The effects of thyroxine (TX) or propylthiouracil (PPT) administration on the antibody forming activity agains t sheep red blood cell (SRBC) and Newcastle disease virus (NDV) were studied by using of hemagglutination and hemagglutination-inhibition techniques. Antibody titers to both SRBC and NDV increased significantly in the TX-treated group, whereas decreased in the PPT-treated group, compared with control. When TX was administered after antigen inoculatioon, antibody forming activity was significantly enhanced, compared with the TX administration before antigen inoculation.

• YAKHAK HOEJI
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• v.46 no.4
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• pp.270-275
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• 2002

The lectin gene from rice was amplified by the polymerase chain reaction. The amplified DNA was inserted into the expression vector pET26b and expressed it as a fusion protein with polyhistidine sequences in Escherichia coli. The recombinant protein was produced by induction with 0.4 mM isopropyl-$\beta$-D-thiogalactopyranoside at 37$^{\circ}C$ and purified by an immobilized metal affinity chromatography. The recombinant protein was found to have lectin activity by the hemagglutination inhibition assay. The hemagglutination activity of the recombinant protein was optimal at pH 4.0-7.0 and was dependent on $Ca^{2+}$ and Mn$^{2+}$.2+/.

• YAKHAK HOEJI
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• v.51 no.4
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• pp.259-263
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• 2007

We previously reported the isolation of a sialic acid-specific lectin eluted from the bark of Maackia fauriei using alkaline buffer on a fetuin-affinity column. Application of a borate-based elution buffer in the present study increased the specific activity of purified lectin from crude protein extract by 2.6-fold, whilst only slightly decreasing the recovery by 1.13%. The biological properties of the lectin eluted with borate buffer were the same as those of the lectin eluted with alkaline buffer such as in terms of the hemagglutination activity, hemagglutination inhibition activity, molecular mass, purity, and cytotoxicity to human breast cancer cells. A prepared biotin-labeled lectin conjugate was used to investigate the binding to various glycoproteins. Our results indicate that eluting with borate buffer is more efficient than using alkaline buffer to isolate the lectin adsorbed in a fetuin-affinity column.

• Journal of Microbiology and Biotechnology
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• v.13 no.6
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• pp.853-858
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• 2003

Helicobacter pylori specifically adhere to host cells through a number of putative receptors and ligands, mainly based on carbohydrate-protein interactions. Polysaccharide fractions isolated from the leaves of Artemisia capillaris showed different inhibitory activities against H. pylori adhesion by using hemagglutination assay. Among these fractions, an acidic polysaccharide fraction FlA showed highly effective inhibitory activity, and its minimum inhibition concentration was 0.63 mg/ml. The inhibition results by the hemagglutination assay were consistent with those obtained by the enzymelinked glycosorbent assay, which was developed by the conjugation of horseradish peroxidase with fetuin, a sialic acid-containing glycoprotein which was specific to H. pylori adhesion. FlA contained the highest carbohydrate content among polysaccharide fractions, and no protein was detectable when further purified by gel filtration FPLC. Sugar composition analysis using GC revealed the highest amount of galacturonic acid among sugars, which suggests that FlA contains essentially acidic polysaccharides. Our data suggest that acidic polysaccharides may play an important role in the inhibition of H. pylori adhesion to host cells.

• The Journal of the Korean Society for Microbiology
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• v.22 no.2
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• pp.147-153
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• 1987

Colonization factor antigen I(CFA I) has been shown to be one of several virulence factors that promote attachment of enterotoxigenic E. coli(ETEC) to small intestinal epithelial cells of humans. The ability of ETEC to produce mannose-resistant hemagglutination(MRHA) of human blood group A has been used to detect CFA I. To determine gastrointestinal carriage in Korean children of E. coli with MRHA and CFA I, 116 strains of E. coli from diarrheal children admitted to Hanyang University Hospital were examined for MRHA of human erythrocytes and the presence of CFA I. Of 45 ETEC strains, 18(40%) gave a positive MRHA($MRHA^+$) and eight(18%) were positive for CFA I(CFA $I^+$). ETEC with CFA I were all heat-stable enterotoxin(ST) producers and two of these strains were of serogroups $O_{25}$. Of 17 classic enteropathogenic E. coli(EPEC), 7(41%) were $MRHA^+$ but all were negative for CFA I(CFA $I^-$). Of 30 enteroadherent E. coli(EAEC) strains, 11(37%) were $MRHA^+$ and one was CFA $I^+$. Of 24 nonpathogenic E. coli, 4(17%) were $MRHA^+$ but all were CFA $I^-$. It was shown that MRHA was common in all strains of E. coli, CFA I was limited only to ST producing ETEC and EAEC; although MRHA is a useful screening procedure, serologic tests seem to be necessary to comfirm CFA I production. CFA I was associated with a lower proportion of ETEC isolates in Korea than has been reported for other locations.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.6
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• pp.863-868
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• 2004

Lectin activities and chemical characteristics of Escherichia coli, Lactobacillus spp. and Bifidobacterium spp. originating from the porcine cecal mucosal layer were studied based on hemagglutination assay (HA) and hemagglutination inhibition assay (HIA). Although all the bacterial strains were able to agglutinate erythrocytes of porcine or rabbit origin, much higher HA titers were consistently observed for Lactobacillus spp. than for E. coli or for Bifidobacterium spp. A remarkable reduction in HA titers occurred by the treatment of E. coli and Lactobacillus spp. with protease or trypsin and of Bifidobacterium spp. with protease, trypsin or periodate. There were no significant effects on the HA titers of the three groups of bacteria after the treatment with lipase. Hemagglutination of E. coli was strongly inhibited by D (+)-mannose and D (+)-galactose; Lactobacillus spp. by $\alpha$-L-rhamnose and methyl-$\beta$-galactopyranoside; Bifidobacterium spp. by D (+)-alactose, $\alpha$-L-rhamnose, $\alpha$-L-fucose, L (+)-arabinose, D (+)-mannose, D (-)-fructose at a relatively low concentration (1.43 to 3.75 mg/ml). These results, combined with the enhanced HA activities of the three bacterial strains by modification of rabbit erythrocytes with neuraminidase and abolished HA activity of E. coli after treatment with $\beta$-galactosidase, indicate that it might be the glycoproteinous substances surrounding the surface of the bacterial cells that are responsible for the adhesions of these microorganisms by recognizing the specific receptors on the red blood cell.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.48-54
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• 1999

Effects of zinc chloride (Zn) on the immune responses of lipopolysaccharide (LPS) were studied by using ICR mice. Mice were divided into 4 groups (10 mice/group), and Zn was given to the mice with i.p. injection at 0.3 mg/kg 5 times a week for 14 days, and 1 hr after Zn administration, LPS was given with i.p. injection at 5 mg/kg twice a week. Mice were immunized and challenged with sheep red blood cells (SRBC). Immunobiological responses were evaluated by humoral, cellular and nonspecific immunity. LPS treatment significantly increased the relative weights of spleen and thymus, hemagglutination titer (HA) and proliferation of splenocytes compared with those in controls, but significantly decreased the body weight gain. Zn treatment significantly increased proliferation of splenocytes and circulating leukocytes compared with those in controls. Combination of Zn and LPS significantly decreased the body weight gain and proliferation of splenocytes compared with those in controls. Combination of Zn and LPS significantly decreased HA and proliferation of splenocytes than in LPS alone. These findings indicate that zinc lowered the humoral immune responses of LPS.