• The Journal of the Korean Society for Microbiology
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• v.21 no.1
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• pp.33-45
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• 1986

On hundred and forty stains of shigella cultures isolated from the twelve hygiene laboratories of cities and provincial general hospital laboratories in 1983 were tested for their resistance to thirteen antimicrobial drugs and their R-plasmid transfer. Antimicrobial drugs were used amikacin, ampicillin, cephalothin, chloramphenicol, gentamicin, kanamycin, nalidixic acid, rifampicin, streptamycin, tetracycline, tobramycin, cefoperazone and piperacillin. All strains were resistant to one or more of thirteen antimicrobial drugs but 94.3% were susceptible to amikacin, gentamicin and tobramycin of total isolated. The most strains commonly found resistance was to chloramphenicol (94%) followed by streptamycin (93%), tetracyline (92%) piperacillin (90%) ampicillin (83%), cefoperazone (42%), nalidixic acid (14%), cephalothin (17%), rifampicin (22%) and kanamycin (6%), sixty percent of strains among 140 were resistance to ampicillin, chloramphenicol, streptomycin, tetracycline at the same time. The transfer of drug resistance by conjugation was tested and ninety four strains (94.3%) were resistant to one or more drugs were found to transfer their drug resistance of E. coli. percentage of transfer frequency by conjugation was one strains (54%), the transfer frequency of drug resistance varied by donor strains and recipients, but not by selecting drugs. Resistance to nalidixic acid was not transferred by conjugation to recipients. Percentage of plasmid curing after the treatment of acriflavine, acridine orange was about 8%. Among strains cured two strains were tested compare original strains with them in biochemical properties in arginine dihydrolase and arabinose fermentation reaction. It was found to growth curves of No.2 shigella flexneri, serotype 1b, and its derivatives cured with acriflavine in $M{\ddot{u}}ller$ Hinton broth medium (pH 7.4, $38^{\circ}C$) by temperature Gradient Biophoto Recorder TN-1120 (Tokyo, Japan).

• Korean Journal of Pharmacognosy
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• v.42 no.2
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• pp.117-126
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• 2011

Twenty-two compounds were isolated from the 70% ethanolic extract of Rehmanniae Radix Preparata (Scrophulariaceae) and their structures were identified as three triterpenoids [oleanolic acid (1), pomonic acid (2) and ursolic acid (5)], an iridoid, catalpol (13), four furan derivatives [5-hydroxymethyl-2-furaldehyde acetate (3), 5-hydroxymethyl-2-furfural (6), 5-hydroxymethyl-2-furancarboxylic acid (7), and 5-(${\alpha}$-D-galactopyranosyloxymethyl)-2-furancarboxaldehyde (15)], three phenethyl alcohol glycosides [darendoside B (14), phenethyl alcohol 2-O-${\beta}$-D-xylopyranosyl(1${\rightarrow}$6)-${\beta}$-D-glucopyranoside (17), and salidroside (19)], four sugar derivatives [L-arabinose (11), raffinose (20), stachyose (21), and mannitol (22)], and seven others [2,5-dihydroxyacetophenone (4), succinic acid (8), daucosterol (9), ${\beta}$-sitosterol (10), adenosine (16), uridine (18) jio-cerebroside (12)]. The chemical structures of these compounds were identified on the basis of spectroscopic methods and comparison with literature values. This is the first report of the triterpenoids oleanolic acid (1), pomonic acid (2), and ursolic acid (5) from the genus Rehmannia, as well as the first report of compounds 5-hydroxymethyl-2-furaldehyde acetate (3), 2,5-dihydroxyacetophenone (4), daucosterol (9), darendoside B (14), 5-(${\alpha}$-D-galactopyranosyloxymethyl)-2-furancarboxaldehyde (15), adenosine (16), phenethyl alcohol 2-O-${\beta}$-D-xylopyranosyl(1${\rightarrow}$6)-${\beta}$-D-glucopyranoside (17), and salidroside (19) from the Rehmanniae Radix Preparata.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.177-177
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• 1993

뇌모세혈관내피세포로 구성된 혈액-뇌관문(BBB)은 tight junction으로 구성되어 있을뿐만 아니라 fenestra가 없는 등 BBB가 가진 특성으로 인해 물질 수송에 장벽역할을 하기 때문에 주로 중추신경계 질환시의 약물요법에 많은 제한이 따른다. 따라서 뇌로의 효율적인 약물 송달방법에 대해 많은 연구가 진행중에 있는데 본 연구에서는 BBB의 hyperosmotic opening법을 이용하여 뇌로 잘 수송되지 않는 약물의 뇌송달 방법에 대해 연구하고자 하였다. 먼저 수용성으로 인해 BBB 에 잘 통과하지 않는 물질로 신장 및 뇌영상 촬영시 사용되는 방사성 의약품이 Tc-DTPA를 이용하여, hyperosmotic opening법에 의한 뇌투과 증가정도를 검토하였으며, 실험방법이 확립됨에 따라 뇌암의 항암요법을 위해 뇌로의 투과가 적은 항암제(5-Fluorouracil, 5-FU)의 뇌송달에 대해 본 방법을 적용하여 검토하였다. 실험동물로는 S.D.계 웅성 랫트를 사용하였으며, 실험방법은 다음과 같이 하였다. 랫트의 좌측 외경동맥(left external carotid artery)에 혈류의 역방향으로 혈관 분지점에서 1-2mm 전까지 PE-50 catheter를 삽입하고, 1.6 molal L－(＋)－ arabinose 고장액(1580mOsm)을 0.12ml/sec의 일정한 속도로 30초간 infusion함으로 BBB를 opening 한 다음, 5분 후에 Tc-DTPA를 대퇴 정맥으로 주사하여 0, 10, 30초, 1, 1.5, 2, 3, 4, 5, 7 및 10분 간격으로 대퇴동맥에 설치한 카테타로부터 혈액을 채취하고 마지막 혈액을 취한 후 즉시 단두하여 뇌를 적출하였다. 채취한 뇌를 액체질소에 담근 후 tissue Tek으로 고정하고 autoradiography를 하기 위한 slice와 농도측정을 위해 필요한 부위를 취한 후 감마카운터로 Tc-DTPA의 brain각 부위별 및 혈장농도를 측정하였다. 뇌조직중 혈액부피의 측정은 Tc-albumin를 이용하여 구하였다. 같은 방법으로 5-FU에 대한 실험도 행하였고, 이때 각 혈장 및 조직중의 5-FU함량은 HPLC로 하였다.

• Korean Journal of Veterinary Service
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• v.26 no.2
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• pp.121-128
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• 2003

This study was carried out to identify and investigate antimicrobial susceptibility for Mannheimuia haemolytical which is responsible for shipping fever. Samples were collected from nasal and lung of 100 adult healthy cattle which are slaughtered in Samsung meat corporation located in Incheon metropolitan city. lung lesion index have been investigated within 0-5 range according to Shewen and Willkie(Can J Vet Res 52:30-36, 1988). Eighty-seven of 100 cattle were under normal condition with 0-1 ranges. A total of 129 strains were collected from blood and tryptic soy agar. Among these strains, 100 strains were identified with Staphylococcus, Streptococcus and enterobacteria containing E coli. Biochemical and fermentation assay of arabinose, trehalose, xylose, mannose, mannitol, lactose and salicin were tested to identify with Mannheimia sp. for 7 strains shown haemolytic activity on blood agar. Five strains were identified with Mannheimia haemolytica and 2 strains were untyped. In seasonal survey, Mannheimia sp recovered from fall to winter(5 of 7) have been highly isolated rather than those from spring to summer(2 of 7). Mannheimiz haemolytica were susceptible to antibacterials tested in this study but more resistant to oxytetracycline and streptomycin.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.526-534
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• 2019

Chlorella gloriosa (Chlorellaceae, Trebouxiophyceae) was isolated from seawater off the coast of the Dokdo Islands in Korea. An axenic culture was established using the streak-plate method on f/2 agar media supplemented with antibiotics, allowing identification of the isolate by morphological, molecular, and physiological analyses. The morphological characteristics observed by light and electron microscopy revealed typical morphologies of C. gloriosa species. The molecular phylogenetic inference drawn from the small-subunit 18S rRNA sequence verified that the microalgal strain belongs to C. gloriosa. Additionally, gas chromatography-mass spectrometry analysis showed that the isolate was rich in nutritionally important omega-3 and -6 polyunsaturated fatty acids and high-performance liquid chromatography analysis revealed that the high-value antioxidants lutein and violaxanthin were biosynthesized as accessory pigments by this microalga, with arabinose, galactose, and glucose as the major monosaccharides. Therefore, in this study, a Korean marine C. gloriosa species was discovered, characterized, and described, and subsequently added to the national culture collection.

• Food Science and Biotechnology
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• v.16 no.6
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• pp.928-934
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• 2007

Physiochemical properties, such as yield and molecular weight distribution of polysaccharide fractions, of polysaccharides in the enzymatic hydrolysates of purslane were investigated and characterized. A higher amount of micro nutrients, such as potassium (9,413 mg/100 g), phosphorus acid (539 mg/100 g), leucine, alanine, lysine, valine, glycine, and isoleucine, was present in whole purslane. The yield of water soluble polysaccharides (WSP) was 0.29, 7.01, and 7.94% when extracted using room temperature water (RTW), hot-water (HW), and hot temperature/high pressure-water (HTPW), respectively, indicating that HW or HTPW extraction may be effective to obtain WSP from purslane. The average ratio of L-arabinose:D-galactose in the WSP was 37:49, 34:37, and 27:29, when extracted using RTW, HW, and HTPW, respectively. These results indicate that water was a suitable extraction solvent for preparation of the arabinogalactan component of whole purslane. A higher yield and total carbohydrate content was obtained by using Viscozyme L instead of Pectinex 5XL during extraction of the WSP, which indicates that enzymatic treatment of purslane may be an effective method to control the Mw of polysaccharides. Finally, it was confirmed that Viscozyme L is a suitable enzyme for the hydrolysis and separation of polysaccharides obtained from purslane.

• Preventive Nutrition and Food Science
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• v.21 no.3
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• pp.245-254
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• 2016

Water-soluble polysaccharides isolated from the rhizome of Polygonatum sibiricum and fractionated using ionexchange chromatography were investigated to determine their structure and immunostimulating activity. Crude and fractions ($F_1$ and $F_2$) consisted of carbohydrates (85.1~88.3%) with proteins (4.51~11.9%) and uronic acid (1.79~7.47%), and included different levels of mannose (62.3~76.3%), glucose (15.2~20.3%), galactose (4.35~15.3%), and arabinose (4.00~7.65%). The crude contained two peaks with molecular weights (Mw) of $151{\times}10^3$ and $31.8{\times}10^3$, but $F_1$ and $F_2$ exhibited one major peak with Mw of $103{\times}10^3$ and $628{\times}10^3$, respectively. Little immunostimulatory activity was observed by the crude; however, $F_1$ and $F_2$ significantly activated RAW264.7 cells to release nitric oxide and various cytokines, suggesting they were potent immunostimulators. The backbone of the most immunostimulating fraction ($F_1$) was ($1{\rightarrow}4$)-manno- and ($1{\rightarrow}4$)-gluco-pyranosyl residues with galactose and glucose attached to O-6 of manno-pyranoside.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.7-12
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• 2010

The biochemical study of sugar uptake in yeasts started five decades ago and led to the early production of abundant kinetic and mechanistic data. However, the first accurate overview of the underlying sugar transporter genes was obtained relatively late, due mainly to the genetic complexity of hexose uptake in the model yeast, Saccharomyces cerevisiae. The genomic era generated in turn a massive amount of information, allowing the identification of a multitude of putative sugar transporter and sensor-encoding genes in yeast genomes, many of which are phylogenetically related. This review aims to briefly summarize our current knowledges on the biochemical and molecular features of the transporters of pentoses in yeasts, when possible establishing links between previous kinetic studies and genomic data currently available. Emphasis is given to recent developments concerning the identification of D-xylose transporter genes, which are thought to be key players in the optimization of S. cerevisiae for bioethanol production from lignocellulose hydrolysates.

• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.267-273
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• 2011

Methyl violet, used extensively in the commercial textile industry and as a biological stain, is a hazardous recalcitrant. Aspergillus sp. strain CB-TKL-1 isolated from a water sample from Tsumoriri Lake, Karzok, Ladakh, India, was found to completely decolorize methyl violet within 24 h when cultured under aerobic conditions at $25^{\circ}C$. The rate of decolorization was determined by monitoring the decrease in the absorbance maxima of the dye by UV-visible spectroscopy. The decolorization of methyl violet was optimal at pH 5.5 and $30^{\circ}C$ when agitated at 200 rpm. Addition of glucose or arabinose (2%) as a carbon source and sodium nitrate or soyapeptone (0.2%) as a nitrogen source enhanced the decolorization ability of the culture. Furthermore, the culture exhibited a maximum decolorization rate of methyl violet after 24 h when the C:N ratio was 10. Nine N-demethylated decolorized products of methyl violet were identified based on UV-visible spectroscopy, Fourier transform infrared (FTIR), and LC-MS analyses. The decolorization of methyl violet at the end of 24 h generated mono-, di-, tri-, tetra-, penta-, and hexa-N-demethylated intermediates of pararosaniline. The variation of the relative absorption peaks in the decolorized sample indicated a linear decrease of hexa-N-demethylated compounds to non-N-demethylated pararosaniline, indicating a stepwise N-demethylation in the decolorization process.

• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.177-183
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• 2013

Bacterial blight, an important and potentially destructive bacterial disease in rice caused by Xanthomonas oryzae pv. oryzae (Xoo), has recently developed resistance to the available antibiotics. In this study, mass spectrometry (MS)-based metabolite profiling and multivariate analysis were employed to investigate the correlation between timedependent metabolite changes and antimicrobial activities against Xoo over the course of Phomopsis longicolla S1B4 fermentation. Metabolites were clearly differentiated based on fermentation time into phase 1 (days 4-8) and phase 2 (days 10-20) in the principal component analysis (PCA) plot. The multivariate statistical analysis showed that the metabolites contributing significantly for phases 1 and 2 were deacetylphomoxanthone B, monodeacetylphomoxanthone B, fusaristatin A, and dicerandrols A, B, and C as identified by liquid chromatography-mass spectrometry (LC-MS), and dimethylglycine, isobutyric acid, pyruvic acid, ribofuranose, galactofuranose, fructose, arabinose, hexitol, myristic acid, and propylstearic acid were identified by gas chromatography-mass spectrometry (GC-MS)-based metabolite profiling. The most significantly different secondary metabolites, especially deacetylphomoxanthone B, monodeacetylphomoxanthone B, and dicerandrol A, B and C, were positively correlated with antibacterial activity against Xoo during fermentation.