• Korean Journal of Pharmacognosy
• /
• v.11 no.2
• /
• pp.69-74
• /
• 1980

The rhizome of Polygonatum robustum Nakai (Liliaceae) has been used as a crude drug for the purpose of tonic and thirst cure in Korea. The dried rhizomes were extracted with hot ether, then the residue was extracted with hot alcohol. 1) The three kinds of chemical constituents, substance, I, II and III were isolated by silicagel column chromatography from ether and alcohol extracts of the rhizomes. Substance I was confirmed as ${\beta}-sitosterol$, $C_{29}H_{50}O$ by mass and IR spectroscopy. Substance II was identified as stigmasterol by GLC. 2) Substance III was obtained by crystallization from the column chromatography of alcohol fraction. It was suggested as diosgenin based on chemical and spectral discussions. 3) The concentration of blood sugar was significantly decreased in the group administered the ether extract with 20% dextrose and adrenaline in comparison to that of 20% dextrose and adrenaline along.

• Microbiology and Biotechnology Letters
• /
• v.22 no.6
• /
• pp.700-706
• /
• 1994

Lactic acid bacteria in Kimchi fermentation were tested for inhibitory activity against Gram positive bacteria and Gram negative bacteria. The Lactobacillus brevis (KCCM 35464) was found to produce a antimicrobial substance. It showed relatively wide range of inhibition spectrum against gram positive and gram negative bacteria and maintained the inhibitory activity between pH 4.0 and pH 9.0. The antimicrobial substance was obtained in the stationary growth phase and was purified by gel chromatography. The inhibitory effect of the antimicrobial substance on sensitive bacterial strains was determined by filter paper test. The activity of antimicrobial substa- nce was stable at 75$\circ$C. On the basis of its electrophoretic pattern is SDS-PAGE, antimicrobial substance appeared as a single band of 59 KDalton.

• Journal of Food Hygiene and Safety
• /
• v.10 no.4
• /
• pp.225.1-230
• /
• 1995

The ethanol extract from the root bark of Morus alba showed the strongest antimicrobial activity on the growth of almost all the tested microorganisms which were food-borne pathogens and food-related microorganisms. 1) In order to isolate and purify of antimicrobial substance extracted from the root bark of Morus alba, the antimicrobial substance from the ethanol extract which exhibited a strong antimicrobial activity was purified by solvent fractionation, silica gel column chromatography, TLC and HPLC. Among the fractions fractionated by 4 kind of solvents from the ethanol extract, the antimicrobial activity of ethyl acetate fraction had the strongest antimicrobial activity against B. subtilis. Unknown compound were isolated from the ethyl acetate fraction by silica gel column chromatography, TLC and HPLC and the compounds showed strong absorbance at 207, 217 and 285 nm, therefore, it was supposed to be a kinds of aromatic compound.

• YAKHAK HOEJI
• /
• v.30 no.2
• /
• pp.73-78
• /
• 1986

Peucedanum terebinthaceum Fischer (Umbelliferae) known as "Gi Reum Na Mool" in Korea and used for the treatment of cough, phlegm, headache and common cold etc. The substances were isolated from the fruits of Peucedanum terebinthaceum and identified by UV, GLC, IR, NMR, Mass spectra and physico-chemical tests. The steroidal compounds from the fruits were identified as $\beta$-sitosterol (tR 33.01 min.) and stigmasterol (tR 28.87 min.) by GLC. Substance I (colorless prismatic crystal, $C_{19}H_{20}O_5$, mp $110~111^{\circ}$) was identified as decursin which is one of the pyranocoumarin. Hydrolysis of substance I with 5%-potassium hydroxide produced decursinol. Acetylation of decursinot gave its monoacetate, white needles, $C_{16}H_{16}O_5$. Substance II(light yellowish white needle crystal, $C_9H_6O_3$, mp $227~228^{\circ}$) was proved to be umbelliferone. Substance I, decursin, was isolated for the first time from the fruits of Peucedanum spp. (Umbelliferae).

• Proceedings of the Ginseng society Conference
• /
• 1978.09a
• /
• pp.75-77
• /
• 1978

It was found that water extract of Panax ginseng strongly inhibited adrenaline-induced lipolysis in isolated fat cells of rat epididymal adipose tissue. An antilipolytic action of the water extract was easily inactivated by treatment with pronase, suggesting that the active principle might be a protein or a peptide. Experiments were designed to purify the antilipolytic substance, or insulin-like substance, of the water extract. The water extract was dialyzed against disti'led water. The outer dialysate was subjected to DEAE-cellulose column chromatography, gelfuaration on sephadex G-50 column, avicel cellulose column chromatography and phospho-cellulose column chromatography, successively. The finally purified substance gave one spot on thin layer chromatography. The molecular weight was found to be around 1000. Experiments are now in progress to elucidate the structure of this insulin-like peptide.

• The Plant Pathology Journal
• /
• v.17 no.1
• /
• pp.52-56
• /
• 2001

This study was undertaken to separate and identify antifungla substances produced by Gilocladium virens G1, a biocontrol agent used for the control of plant diseases caused by Rhizoctonea solani. The culture of G. virens G1 effectively inhibited the growth of R. solani, Colletotrichum gloeosporioides, and Phytophthora capsici, but less that of Fusarium oxysporum. The n-hexane extract of the G. virens culture, which was used for the purification of responsible substances, strongly inhibited R. solani and C. gloeosporioides, but not P. capsici, although the n-butanol extract was effective on all of the pathogens tested. An antifungal substance was purified using the n-hexane extract by Silica gel column chromatography and HPLC. The substance was examined for purity by HPLC and for nature by UV spectrometry, which differed from known antibiotic compounds such as gliotoxin, viridin and gliovirin. The antifungal substance was very liphophilic based on its solvent-solubility and Rf values on TLC, and more inhibitory to C. gloeosporioides than other fungal pathogens tested.

• Nuclear Engineering and Technology
• /
• v.55 no.5
• /
• pp.1671-1676
• /
• 2023

The influence of adding iodine as a contrast substance to elevate radiation in a tumor is studied using simulation techniques of Monte-Carlo. The study is carried on a brain cancer by adopting an unsophisticated head phantom. The ionizing radiation source is an external beam of x-rays with energy range of a few tens of keV. The expected radiation dose increment due to adding the iodine is investigated by comparing the radiation in the tumor after and before adding the iodine and calculating the ratio between the two doses. Several concentrations of the contrast substance are used to quantify its impact. The change of the dose increment with the source energy is also examined. It is found that the radiation elevation in the tumor tends to saturate with increasing the iodine concentration, and for the studied domain of energies (30 keV-100 keV), the radiation dose enhancement factors (RDEF) for the different iodine concentrations (1%-9%) show peaked curves, with the peak occurring between 60 keV and 70 keV. For the highest concentration studied, 9%, the peak value is almost 7.

• Analytical Science and Technology
• /
• v.17 no.6
• /
• pp.1043-1058
• /
• 2004

• Food Science of Animal Resources
• /
• v.36 no.3
• /
• pp.319-325
• /
• 2016

This study was conducted to determine the residual amount of veterinary drugs such as meloxicam, flunixin, and tulathromycin in animal products (beef, pork, horsemeat, and milk). Veterinary drugs have been widely used in the rearing of livestock to prevent and treat diseases. A total of 152 samples were purchased from markets located in major Korean cities (Seoul, Busan, Incheon, Daegu, Daejeon, Gwangju, Ulsan and Jeju), including Jeju. Veterinary drugs were analyzed by liquid chromatography-tandem mass spectrometry according to the Korean Food Standards Code. The resulting data, which are located within 70-120% of recovery range and less than 20% of relative standard deviations, are in compliance with the criteria of CODEX. A total of five veterinary drugs were detected in 152 samples, giving a detection rate of approximately 3.3%; and no food source violated the guideline values. Our result indicated that most of the veterinary drug residues in animal products were below the maximum residue limits specified in Korea.

• Analytical Science and Technology
• /
• v.32 no.6
• /
• pp.233-242
• /
• 2019

Substance identification is the first step of the REACH registration. It is essential in terms of Classification, Labelling and Packaging (CLP) regulation and because even trace amounts of impurities or additives can affect the classification. In this study, a scheme for the screening, quantification, and interpretation of trace amounts of hazardous inorganic substances is proposed to detect the presence of more than 0.1% hazardous inorganic substances that have been affecting the hazard classification. An exemplary list of hazardous inorganic substances was created from the substances of very high concern (SVHCs) in REACH. Among 201 SVHCs, there were 67 inorganic SVHCs containing at least one or ~2-3 heavy metals, such as As, Cd, Co, Cr, Pb, Sb, and Sn, in their molecular formula. The inorganic SVHCs are listed in excel format with a search function for these heavy metals so that the hazardous inorganic substances, including each heavy metal and the calculated ratio of its atomic weight to molecular weight of the hazardous inorganic substance containing it, can be searched. The case study was conducted to confirm the validity of the established scheme with zinc oxide (ZnO). In a substance that is made of ZnO, Pb was screened by XRF analysis and measured to be 0.04% (w/w) by ICP-OES analysis. After referring to the list, the presence of Pb was interpreted just as an impurity, but not as an impurity relevant for the classification. Future studies are needed to expand on this exemplary list of hazardous inorganic substances using proper regulatory data sources.