• Food Science and Biotechnology
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• v.14 no.4
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• pp.547-550
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• 2005

Fourteen out of 87 strains of lactic acid bacteria isolated tram Kimchi were found to be resistant against the action of artificial gastric and bile juices. In particular, lactobacilli KM 3, 7, 28, and 37 showed strong resistance and their viable cell counts at the initial stage remained the same even after 3 hours of cultivation in an artificial gastric juice. However, the survival rates of KM 14, 28, and 64 were found to be significantly enhanced in artificial bile juice. Based on the paper disc method, it was evident that isolated lactic acid bacteria showed antibacterial effect against Listeria monocytogenes, Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Vibrio vulnificus, and Salmonella typhimurium. The isolated lactic acid bacteria were identified as Lactobacillus plantarum and Leuconostoc mesenteroides.

• Archives of Pharmacal Research
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• v.27 no.9
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• pp.885-892
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• 2004

Due to the rapidly growing number of resistant strains of bacteria, the search for antibacterial agents with new modes of action will always remain an important and challenging task. Thus, the reaction of 2-substituted or. unsubstituted-4-(4-acetylanilino)-5,6,7,8-terahydrobenzo［b］ thieno［2,3-d］pyrimidine derivatives 1-3 with the hydrazine derivatives, semi and / or thiosemi-carbazides, provided the corresponding hydrazones 4-6 and semi and/or thiosemicarbazones 7-9. Claisen-Schmidt condensation of compounds 1 or 2 with the appropriate aldehyde yielded the chalcones 10, 11 which, when treated with hydroxylamine hydrochloride gave rise to the isoxazoline-containing compounds 12, 13. Furthermore, reacting the respective chalcones 10, 11 with different hydrazines, urea and/or thiourea, furnished compounds 14, 15, 16, and 17 respectively. Representative compounds were tested for their antimicrobial activity against Candida Albicans and certain gram-positive and gram-negative bacteria. Their MICs were then determined. Compound 15e, showed a broad spectrum of activity while most of the other com-pounds showed varying antimicrobial activity.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.47-53
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• 1998

5.7-Dichloro-8-hydroxyquinaldyl-N-ethylcarbamate, one of the carbamate derivative which are generally used as insecticide, was newly synthesized. Its physical properities were determined and chemical structure was indentified by means of I.R., nmr in addition to elemental analysis. The yield of addition, using triethylamine as catalyst, 5.7-dichloro-8-hydroxyquinaldine and isocyanate was better than that of condensation of 5.7-dichloro-8- hydroxyquinaldine with carbamoylchloride. The effect of the cornpond on rabbit's ileum, and antibacterial activity against Staphylococcus aureus, Salmonella typhi, Escherichia coli, and Pseudomonas aeruginosa were examined. It was observed that the dosage over 100 $\mu$g/ml of the compound relaxed rabbit's ileum and the same dosage of the compound inhibited growth of the above strains of bactera.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.79-79
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• 2001

Genotoxic chemotherapeutics are irreversible DNA targeting agents, which can act as anticancer and antiviral drugs. Natural antibacterial and anticancer enediynes function through the formation of free radicals formed by Bergman-type cycloaromatization and being capable of cleavage of DNA strand. They have been focused primarily on the design and syntheses of simple enediyne structures, which can be mimic their mechanistic feature. Recently. I have been reported the possible application of 4'-bromoacetophenone as a simple photoactivatable DNA cleaving agent, which could be readily prepared and exhibit potent and selective DNA cleaving activity. Herein, we further investigated the activity of 4'-bromoacetophenone-pyrrolecarboxamides, which consist of both DNA cleaving element and recognition unit under various conditions in order to get more understanding of the mechanism of the action and find a broad spectrum of application.

• International Journal of Oral Biology
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• v.34 no.2
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• pp.81-86
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• 2009

Baicalin is a flavonoid purified from the medicinal plant Scutellaria baicalensis. It has been reported that baicalin exhibits antibacterial, anti-inflammatory and analgesic effects. The present study was undertaken to determine the underlying cellular mechanisms of baicalin action in preosteoclasts. The effects of this flavonoid on preosteoclasts were determined by measuring osteoclast generation and osteoclast activity in macrophage-colony stimulating factor (M-CSF)-dependent bone marrow cells (MDBMCs) and in co-cultures of MDBMCs and osteoblasts. Osteoclast generation was assayed by measuring the number of tartrateresistant acid phosphatase (TRAP) (+) multinucleated cells after culture. Osteoclast activity was assayed by measuring the area of the resorption pit after culture. We found that osteoclast generation was induced by M-CSF and receptor activator of NF-kB ligand (RANKL), and by the 1.25-dihydroxycholecalciferol in our cultures. Baicalin decreased both osteoclast generation and activity in MDBM cultures and co-cultures indicating that it may inhibit bone resorption.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.416-417
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• 2000

Chitin, a poly $\beta$-(1longrightarrow14)-N-acetyl-D-glucosamine, is best known as a cell wall component of fungi and as a skeletal materials of invertebrates. Chitosan is derived from chitin by deacetylation in the presence of alkali. Chitosan has been developed as new physiological materials since it possesses antibacterial activity, hypocholesterolemic activity and antihypertensive action. However, the actions of chitosan in vivo still remain ambiguous as the physiological functional properties because most animal intestines, especially the human gastrointestinal tract, do not possess enzyme such as chitosanase which directly degrade the $\beta$-glucosidic linkage in chitosan, and consequently the unbroken polymers may be poorly absorbed into the human intestine. Therefore, recent studies as chitosan have attracted interest for chitosan oligosaccharides, because the oligosaccharides process not only water-soluble property but also versatile functional properties such as antitumor activity, immune-enhancing effects, enhancement of protective effects against infection with some pathogens in mice and antimicrobial activity (Kingsnorth et al., 1983, Mori et al., 1997). (omitted)

• Journal of Integrative Natural Science
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• v.1 no.1
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• pp.47-53
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• 2008

In a previous study, we showed that Cecropin A (1-8)-Magainin 2 (1-12) hybrid peptide (CA-MA)'s analogue, Anal P5, exhibit broad-spectrum antimicrobial activity. Anal P5, designed by flexible region (positions 9, 10)-substitution, Lys- (positions 4, 8, 14, 15) and Leu- (positions 5, 6, 12, 13, 16, 17, 20) substitutions, showed an enhanced antimicrobial and antitumor activity without hemolysis. The primary objective of the present study was to gain insight into the relevant mechanisms of antimicrobial activities of Anal P5 by using flow cytometric analysis. Anal P5 exhibits strong antifungal activity in a salt concentration independent manner. In addition, Anal P5 causes significant morphological alterations of the bacterial surfaces as shown by scanning electron microscopy, supporting its antibacterial activity. Its potent antibiotic activity suggests that Anal P5 is an excellent candidate as a lead compound for the development of novel antibiotic agents.

• Proceedings of the KACD Conference
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• 2003.11a
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• pp.560-560
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• 2003

I. Objectives Intracanal medicament with antibacterial action is required to maximize the disinfection of the root canal system. The purpose of this study was to evaluate the efficacy of 2% chlorhexidine digluconate(CHX) and controlled release device(CRD) containing 20% CHX and chitosan coating, compared to calcium hydroxide as intracanal medicament against E. faecalis. II. Materials and Methods One hundred and twenty intact freshly extracted bovine incisors were used and were 0.5% NaOCl. Middle 1/3 portion of roots were sliced into 4mm thick section and cementum was removed using diamond burs and external diameter was approximally 6mm.(omitted)

• Archives of Pharmacal Research
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• v.26 no.8
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• pp.597-600
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• 2003

Silybin has a potent antibacterial activity, more potent than silymarin II, against gram-positive bacteria without hemolytic activity, whereas it has no antimicrobial activity against gram-negative bacteria or fungi. The mode of action of silybin against the gram-positive bacterial cell was examined by investigating the change in plasma membrane dynamics of bacterial cells using 1 ,6-diphenyl-1,3,5-hextriene (DPH) as a membrane probe and by assessing the inhibition of macromolecular synthesis using radiolabeled incorporation assay. The results showed that silybin inhibited RNA and protein synthesis on gram-positive bacteria.

• Korean Journal of Plant Resources
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• v.21 no.6
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• pp.431-434
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• 2008

Dental caries is the destruction of the enamel of teeth by Streptoccus mutans. S. mutans has been isolated from human dental plaque and is associated with the initial development of enamel lesions. We have studied the antibacterial action of the fruit of Callistemon citrin us against a cariogenic bacterium, S. mutans. From the fruit of C. citrinus, piceatannol (3,3',4',5-tetrahydroxystilbene) was isolated by repeated column chromatography with $SiO_2$ and Sephadex LH-20. Its structure was elucidated by instrumental analysis using 1D-NMR, 2D-NMR and EI-MS. This compound was isolated from the fruit of C. citrin us for the first time. The anticarcinogenic activity of this compound was determined by using agar well-diffusion method and minimal inhibition concentration (MIC).