• Journal of Microbiology and Biotechnology
• /
• v.18 no.10
• /
• pp.1666-1671
• /
• 2008

The mite-control activities of materials obtained from Pelargonium graveolens oil against Dermatophagoides farinae and D. pteronyssinus were examined using an impregnated fabric disk bioassay and were compared with those shown by commercial benzyl benzoate and N,N-diethyl-m-toluamide (DEET). Purification of the biologically active constituents from P. graveolens oil was done by silica gel chromatography and high performance liquid chromatography. The structures of the active components were analyzed by EI/MS, $^{1}H$-NMR, $^{13}C$-NMR, $^{1}H-^{13}C$ COSY-NMR, and DEPT-NMR spectra, and were identified as geraniol ($C_{10}H_{18}O$, MW 154.25, trans-3,7-dimethyl-2,6-octadien-l-ol) and $\beta$-citronellol ($C_{10}H_{20}O$, MW 156.27, 3,7-dimethyl-6-octen-l-o1). Based on the $LD_{50}$ values, the most toxic compound was geraniol (0.26${\mu}g/cm^{2}$), followed by $\beta$-citronellol (0.28${\mu}g/cm^{2}$), benzyl benzoate (10.03${\mu}g/cm^{2}$), and DEET (37.12${\mu}g/cm^{2}$) against D. farillae. In the case of D. pteronyssinus, geraniol (0.28${\mu}g/cm^{2}$) was the most toxic, followed by $\beta$-citronellol (0.29${\mu}g/cm^{2}$), benzyl benzoate (9.58${\mu}g/cm^{2}$), and DEET (18.23${\mu}g/cm^{2}$). These results suggest that D. farinae and D. pteronyssinus may be controlled more effectively by the application of geraniol and $\beta$-citronellol than benzyl benzoate and DEET. Furthermore, geraniol and $\beta$-citronellol isolated from P. graveolens could be useful for managing populations of D. farinae and D. pterollyssinus.

• Korean Journal of Soil Science and Fertilizer
• /
• v.39 no.4
• /
• pp.195-203
• /
• 2006

An antagonistic strain, Burkholderia MP-1, showed antimicrobial activity against various filamentous plant pathogenic fungi, yeasts and food borne bacteria (Gram-positive and Gram-negative). The nucleotide sequence of the 16S rRNA gene (1491 pb) of strain MP-1 exhibited close similarity (99-100%) with other Burkholderia 16S rRNA genes. Isolation of the antibiotic substances from culture broth was fractionated by ethyl acetate (EtOAc) solvent and EtOAc-soluble acidic fraction. The antibiotic substances were purified through a silica gel, Sephadex LH-20, ODS column chromatography, and high performance liquid chromatography, respectively. Four active substances were identified as phenylacetic acid, hydrocinnamic acid, 4-hydroxyphenylacetic acid and 4-hydroxyphenylacetate methyl ester by gas chromatographic-mass spectrum analysis. The minimum inhibition of concentration (MIC) of each active compound inhibited the growth of the microorganisms tested at 250 to $2500{\mu}g\;ml^{-1}$. The antimicrobial activity of crude acidic fraction at 1 mg of dry weight per 6 mm paper disc was more effective than authentic standard mixture (four active substances were mixed with the same ratio as acidic fraction) over a wide range of bacterial test.

• Journal of Ginseng Research
• /
• v.39 no.3
• /
• pp.221-229
• /
• 2015

Background: Minor ginsenosides, those having low content in ginseng, have higher pharmacological activities. To obtain minor ginsenosides, the biotransformation of American ginseng protopanaxadiol (PPD)-ginsenoside was studied using special ginsenosidase type-I from Aspergillus niger g.848. Methods: DEAE (diethylaminoethyl)-cellulose and polyacrylamide gel electrophoresis were used in enzyme purification, thin-layer chromatography and high performance liquid chromatography (HPLC) were used in enzyme hydrolysis and kinetics; crude enzyme was used in minor ginsenoside preparation from PPD-ginsenoside; the products were separated with silica-gel-column, and recognized by HPLC and NMR (Nuclear Magnetic Resonance). Results: The enzyme molecular weight was 75 kDa; the enzyme firstly hydrolyzed the C-20 position 20-O-${\beta}$-D-Glc of ginsenoside Rb1, then the C-3 position 3-O-${\beta}$-D-Glc with the pathway $Rb1{\rightarrow}Rd{\rightarrow}F2{\rightarrow}C-K$. However, the enzyme firstly hydrolyzed C-3 position 3-O-${\beta}$-D-Glc of ginsenoside Rb2 and Rc, finally hydrolyzed 20-O-L-Ara with the pathway $Rb2{\rightarrow}C-O{\rightarrow}C-Y{\rightarrow}C-K$, and $Rc{\rightarrow}C-Mc1{\rightarrow}C-Mc{\rightarrow}C-K$. According to enzyme kinetics, $K_m$ and $V_{max}$ of Michaelis-Menten equation, the enzyme reaction velocities on ginsenosides were Rb1 > Rb2 > Rc > Rd. However, the pure enzyme yield was only 3.1%, so crude enzyme was used for minor ginsenoside preparation. When the crude enzyme was reacted in 3% American ginseng PPD-ginsenoside (containing Rb1, Rb2, Rc, and Rd) at $45^{\circ}C$ and pH 5.0 for 18 h, the main products were minor ginsenosides C-Mc, C-Y, F2, and C-K; average molar yields were 43.7% for C-Mc from Rc, 42.4% for C-Y from Rb2, and 69.5% for F2 and C-K from Rb1 and Rd. Conclusion: Four monomer minor ginsenosides were successfully produced (at low-cost) from the PPD-ginsenosides using crude enzyme.

• Journal of Life Science
• /
• v.16 no.2 s.75
• /
• pp.328-332
• /
• 2006

The possible presence of inhibitors of pancreatic lipase (tricaylglycerol acylhydrolase EC 3.1.1.3) was screened from Korean traditional edible or medicinal herbs. Among tested herbs, Arecae pericarpium, Mucunae Caulis, Rhus javanica, Thujae orientalis were shown to have strong inhibitory effect against pancreatic lipase. Thujae orientalis was finally selected as a candidate for pancreatic lipase inhibitor. The extract of Thujae orientalis was showed selective inhibition on porcine pancreatic lipase activity. Active inhibitors, TF-1, TF-2, TF-3, were purified from an extract of Thujae orientalis, using chloroform extraction, followed by successive chromatography in silica gel and LH-20 and high performance liquid chromatography (HPLC). The $IC_{50}$ values of TF-1, TF-2, TF-3 and orlistat were 44.7, 98.7, 46.1 and $27.6{\mu}g/ml$, respectively. And also the TF-2 and orlistat were shown to be inhibitory effect on the differentiation of preadipocyte NIH-3T3 L1 cells at a concentration of $10{\mu}g/ml$.

• Korean Journal of Food Science and Technology
• /
• v.52 no.5
• /
• pp.524-528
• /
• 2020

The aim of this study was to enhance the use of wheat bran in lactic acid bacteria (LAB) fermentation. LAB fermentation of wheat bran and the flavor components and amino acids of fermentation products were analyzed using gas chromatography-mass spectrometry (GC/MS) and high-performance liquid chromatography (HPLC). The results showed that total flavor components increased by 93% and 73% in the animal-based LAB mixture (T2) and plant-based LAB mixture (T3), respectively, after fermentation. Among these components, 2,3-butanedione (diacetyl), known for its buttery flavor, was detected at concentrations of 18.44 ng/g (T2) and 16.95 ng/g (T3). Levels of hexanal and nonanal, which causes off-flavor components in wheat bran, dramatically decreased after T2 fermentation; similarly, levels of total free amino acids decreased by 37.6% (T2) and 36.7% (T3) after fermentation. This may explain why some components were bound to volatile compounds during LAB fermentation. These results suggest that LAB-fermented wheat bran is a potential value-added food material.

• Applied Biological Chemistry
• /
• v.46 no.1
• /
• pp.60-65
• /
• 2003

MMP-1 inhibitory compounds were isolated from 120 Korean traditional edible plants. UP- 1 activity significantly increased linearly with increasing UVB dose in normal human foreskin fibroblast HS68 cell, showing maximum activity at approximately 35 $mJ/cm^2$, whereas in HaCaT cell, normal human keratinocyte, no increase was observed. Maximum secretion of MMP-1 after UVB treatment occurred around 36-48 k after treatment. MMP-1 inhibitory compound isolated from cold-water fraction of Cataegus pinnatifida Bunge showed the mort potent activity. The MMP-1 inhibitory compound was deduced as a peptide based on the fact that pronase digestion decreased the activity whereas periodate oxidation did not. The most potent UP- 1-inhibitory protein, CP-2Va-2, showing an activity of 88.5% against MMP-1, was isolated through sequential column chromatography on DEAE-Toyopearl 650C, Butyl-Toyopearl 650M, and Bio-Gel P-30. Molecular weight of CP-2Va-2 determined through high performance liquid chromatography and SDS PACE was 19 and 20 kDa. respectively, signifying a monomeric structure.

• Korean Journal of Soil Science and Fertilizer
• /
• v.38 no.1
• /
• pp.25-31
• /
• 2005

A soil bacterium, Bacillus subtilis HJ927, exhibiting strong antagonistic property against pathogenic fungi was isolated from pepper fields infested with Phytophthora capsici. Pepper plants inoculated with P. capsici revealed severe root mortality while plants co-inoculated with B. subtilis HJ927 and P. capsici showed drastically reduced root mortality. Low molecular weight substances released by B. subtilis HJ927 mediated the plant protective effect. The anti-fungal compounds released by B. subtilis HJ927 were identified as 3-methylbutyric acid, 2-methylbutyric acid, and methyl 2-hydroxy, 3-phenylpropanoate by high-performance liquid chromatography and gas chromatography-mass spectrometry. In addition to these compounds, B. subtilis HJ927 also produced ${\beta}$-1,3-glucanase, a hydrolytic enzyme implicated in antifungal activity.

• Microbiology and Biotechnology Letters
• /
• v.10 no.4
• /
• pp.267-273
• /
• 1982

Among 12 kinds of ginsenosides in ginseng saponin, ginsenoside-Rb$_1$was contained the most abundantly. But ginsenoside-Rd which is similar to ginsenoside-Rb$_1$in structure, was known to be superior to ginsenoside-Rb$_1$pharmaceutically. In order to convert ginsenoside-Rb$_1$into ginsenoside-Rd by microbial enzyme treatment, a Rhizopus sp. was selected among various strais of molds found in rotten ginseng roots. Enzyme was prepared from the extract of wheat bran koji culture by ammonium sulfate precipitation (1.0 sat'd) and succeeding ammonium sulfate fractionation method (0.6-0.9 sat'd). For the purpose of use as substrate, saponins were purified by the several purification steps from alcohol extract of red ginseng roots. We obtained the total saponin which was composed of 36.5% of ginsenoside Rb$_1$, 12.2% of ginsenoside-Rd and other ginsenosides. For increase of ginsenoside-Rb$_1$ component ratio, we also obtained further purified ginsenoside-Rb group saponin containing 54.5% of ginsenoside-Rb$_1$, 1.1% of ginsenoside- Rd and other ginsenosides from purified the total saponin. In the enzymatic reaction system including the total saponin or the ginsenoside-Rb group saponin, we confirmed the specific conversion of ginsenoside-Rb$_1$to ginsenoside-Rd proportionally and no change of any other ginsenoside patterns by thin layer chromatography and high performance liquid chromatography.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.25 no.2
• /
• pp.144-150
• /
• 1992

Paralytic shellfish toxins in mussels Mytilus edulis and dinoflagellate Alexandrium tamarene from Jinhae Bay, south coast of Korea were investigated. The mussels collected in March-April, 1989 showed toxicities of 7.5 MU/g of whole meat(31-88 MU/g of the digestive gland) , and those collected in 1990 showed toxicity level of 1.9-9.9 MU/g of whole meat by the standard mouse bioassay. Analysis of toxins by high performance liquid chromatography revealed the presence of gonyautoxin 1-4$(48-76\%)$ gonyautoxin 8 and epi-gonyautoxin $8(C1-C2,\;14-39\%)$, saxitoxin$(1-10\%)$, neosaxitoxin$(l-7\%)$ and trace amount of decarbamoylgonyautoxin 2 and 3(dcGTX2, dcGTX3) in the mussels of 1989. While, Mussels collected in 1990 contained a significantly larger proportion of neosaxitoxin $(44-50\%)$ than did those of 1989. A. tamarense isolated in April 1989 produced the same toxins in culture with slightly higher proportion of Cl, C2, dcGTX2 and dcGTX3 than in the mussels. The difference was within a range of toxin change during accumulation by shellfish and during sample preparation for analysis. It was thus concluded that the dinoflagellate was the cause of toxins in the mussels.

• Korean Journal of Veterinary Service
• /
• v.31 no.3
• /
• pp.385-395
• /
• 2008

This study was carried out to investigate the residue level of fluoroquinolones in hen's general eggs and specific eggs by microbiological assay method and high performance liquid chromatography (HPLC) method. HPLC separation was carried out by reversed phase chromatography on a Symmetry $C_{18}$ (250${\times}$4.6 mm, $5{\mu}m$ particle size) with a phase composed of distilled water (containing 0.4% triethylamine and phosphoric acid) : Methanol (780 : 220, v/v), pumped isocratically at a flow rate of 1.0ml/min. A fluorescence detector was utilized with an excitation wavelength of 278nm and an emission wavelength of 456nm. The calibration curves were linear $({\gamma}^2{\geq}0.999)$ over a concentration range of $0.025{\sim}0.4{\mu}g/ml$. Average recoveries of the five fluoroquinolones in whole eggs at fortified levels of $0.05{\sim}0.2{\mu}g/g$ were ranged mean $78.1{\sim}91.7%$ and low coefficient of variation was less than 10% for all analysed samples. The limits of detection and limits of quantification for whole eggs were $1.2{\sim}6.0ng/g$ and $2.3{\sim}9.1ng/g$, respectively. Only one hen's general eggfrom chicken farm in Incheon was detected with the residual fluoroquinolones (Microbiological assay method; 1 of 47 general eggs) ; the range of residual concentration enrofloxacin was 0.12ppm. Those in food stores were detected with the residual fluoroquinolones (Microbiological assay method; 4 of 88 general eggs) ; the ranges of residual concentration enrofloxacin were $0.15{\sim}2.2 ppm$, ciprofloxacin $0.01{\sim}0.06ppm$, and hen's specific eggs (40) in food stores were not detected. For the microbiological assay method of fluoroquinolones in hen's eggs, as the results of comparative analysis, the disc diffusion method with E coli may be a little highly detected for the residual fluoroquinolones.