• Natural Product Sciences
• /
• v.7 no.4
• /
• pp.120-123
• /
• 2001

To develop systems for economic production of useful essential oil compounds, callus was induced from the seedlings of Agastache rugosa and cultured on MS medium. The volatile oil fraction was extracted from the callus and investigated by mean of GC-MS. The composition of the oil was compared with that of the mother plant. As a result, sixty five compounds including ferruginol were identified in the essential oil fraction. The main component of the oil from the leaves of Agastache rugosa was methyl chavichol (53.6%). Methyl jasmonate and jasmonic acid were added to the culturing cell suspension, separately and the composition of induced oil were compared. The oils from cultured cells treated with jasmonates showed considerably different patterns. Especially, the peak of estragole was found in callus oil after treatment with methyl jasmonate as though the amount was limited to 0.58%. In general, the TIC pattern of GC-MS of the callus oil became more similar to the oil from the leaves after elicitation.

• Macromolecular Research
• /
• v.11 no.2
• /
• pp.87-91
• /
• 2003

Thermal decomposition reactions of polystyrene using a new heating medium were carried out by a batch system at 190-280 $^{\circ}C$ to clarify the manner in which decomposition is initiated. Polystyrene obtained from a commercial source and low molecular weight compounds obtained from the thermal decomposition were analyzed by GC, GPC, IR, $^{13}$ C-NMR and GC-MS. The main chain underwent virtually no change by heat application. Polystyrene underwent decomposition below its molding temperature and the major decomposition products were 2,4,6-triphenyl-1-hexene (trimer), 2,4-diphenyl-1-butene(dimer) and styrene (monomer). Ethylbenzene, propylbenzene, naphthalene, benzaldehyde, biphenyl and 1,3-diphenylpropane were detected as minor products. This paper presents a new method for examining the decomposition of polystyrene at low temperature into volatile low molecular weight compounds.

• 한국약용작물학회:학술대회논문집
• /
• 2010.10a
• /
• pp.430-430
• /
• 2010

In this study ethanol extracts of aerial part of Geranium thunbergii Sieb. et Zucc. was investigated for their ability to inhibit a-glucosidase, and thus was fractionated using two organic solvents, including dichloromethane, ethyl acetate. The ethyl acetate-soluble fraction, which manifested potent enzyme inhibitory properties, was then followed by tracking down the active compound by combining HPLC micro-fractionation to an enzyme assay in 96-well plate. The ${\alpha}$-glucosidase inhibitory activity profile showed that two peaks exhibited potent inhibitory activity, and then the structural analyses of the two peaks were carried out by HPLC-UV-MS. The main ${\alpha}$-glucosidase inhibitory compounds in the ethyl acetate-soluble fractions of ethanol extracts of Geranium thunbergii Sieb. et Zucc. were tentatively identified as geraniin and kaempferol-7-rhamnoside.

• Journal of Ginseng Research
• /
• v.19 no.3
• /
• pp.254-259
• /
• 1995

The content and composition of saponin compounds of Panax species were analyzed according to their species, region and processing type of red and white ginseng. The species employed were Korean-, Chinese-, Japanese red ginsengs, and Korean white ginseng of Panax ginseng, American- and Canadian ginsengs of Panax quinquefolium, and Panax notoinseng. Twelve main saponin components in the ginseng were identified and quantified using TLC and HPLC. All three species had remarkably different content and composition. However, within each species they were similar. Twelve major ginsenosides were determined in P. ginseng, eight in p. quinquefolium, and six in P. notoginseng. Of the components of P ginseng Rf, $Rh_1$, $Rh_2$ and Ra were not detected in P quinquefolium, and $Rb_2$, Rc, Rf, $Rh_2$, Ra and Ro not detected in P. notoinseam. Crude saponin content and protopanaxadiol/protopanaxatriol saponin ratio were compared. They were 4.81~5.24% and 1.27~ 1.45 in p. ginsengs, 7.01~7.25% and 2.12~ 2.15 in p. quinquefolium, 9.80% and 0.99 in P. notoineng. The prosapogenin and sapogenin content were different among the Panax species.

• Journal of Ginseng Research
• /
• v.36 no.1
• /
• pp.1-15
• /
• 2012

The major commercial ginsengs are Panax ginseng Meyer (Korean ginseng), P. quinquifolium L. (American ginseng), and P. notoginseng (Burk.) FH Chen (Notoginseng). P. ginseng is the most commonly used as an adaptogenic agent and has been shown to enhance physical performance, promote vitality, increase resistance to stress and aging, and have immunomodulatory activity. These ginsengs contain saponins, which can be classified as dammarane-type, ocotillol-type and oleanane-type oligoglycosides, and polysaccharides as main constituents. Dammarane ginsenosides are transformed into compounds such as the ginsenosides $Rg_3$, $Rg_5$, and $Rk_1$ by steaming and heating and are metabolized into metabolites such as compound K, ginsenoside $Rh_1$, proto- and panaxatriol by intestinal microflora. These metabolites are nonpolar, pharmacologically active and easily absorbed from the gastrointestinal tract. However, the activities metabolizing these constituents into bioactive compounds differ significantly among individuals because all individuals possess characteristic indigenous strains of intestinal bacteria. To overcome this difference, ginsengs fermented with enzymes or microbes have been developed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.18 no.3
• /
• pp.262-269
• /
• 2006

Formaldehyde and total volatile organic compounds (TVOC) from building materials have been known as main causes of IAQ problem in Newly-Constructed Multi-Family Houses. Because Multi-Family Houses are built in large quantities in a similar manner, inappropriate selection of building materials and method will detrimental affect IAQ. This research aims to identify major causes of Indoor Air Pollutants in Multi-Family Houses, by constructing Mock-Up & One-Room House. As a result, self leveling concrete, door, and furniture construction is a major cause of indoor formaldehyde increase, and tile bond is TVOC, and urethane water proof is Etylbenzene, and Xylene.

• Journal of Microbiology and Biotechnology
• /
• v.22 no.12
• /
• pp.1597-1604
• /
• 2012

Genus Bacillus is a spore-forming bacterium that has unique properties in cell differentiation, allowing the forming of spores in stress conditions and activated in the vegetative cell, with suitable environments occurring during the life cycle acting as a trigger. Their habitat is mainly in soil; thus, many species of Bacillus are associated with plants as well as rhizosphere bacteria and endophytic bacteria. Signal transduction is the principal mechanism of interactions, both within the cell community and with the external environment, which provides the subsequent functions or properties for the cell. The antimicrobial compounds of Bacillus sp. are potentially useful products, which have been used in agriculture for the inhibition of phytopathogens, for the stimulation of plant growth, and in the food industry as probiotics. There are two systems for the synthesis of these substances: nonribosomal synthesis of cyclic lipopeptides (NRPS) and polyketides (PKS). For each group, the structures, properties, and genes of the main products are described. The different compounds described and the way in which they co-exist exhibit the relationship of Bacillus substances to plants, humans, and animals.

• Fire Science and Engineering
• /
• v.8 no.1
• /
• pp.3-8
• /
• 1994

A new test system was established to measure the flame extinguishing concentration of Halon alternatives. The main characteristic of this system is to use the solid paraffin with a wick instead of liquid fuel, such as n-Heptane. Our results showed that the extinguishing concentration of compounds was lower than that of other existing data, but the trend was consistent with others. The flame extinguishing concentration of all tested compounds were not almost effected by gas flow velocity. The system produces good reliable data with a minimum error for measuring the flame extinguishing concentration. Therefore our new system can be utilized as a standard equipment to evaluate Halon alternatives.

• Journal of the Semiconductor & Display Technology
• /
• v.18 no.1
• /
• pp.42-47
• /
• 2019

The four different polymer compounds were manufactured to make cable sheath for ship industry. Two kinds of ethylene-vinyl acetate (EVA) were selected as main matrix polymers for compounding with fire retardant, crosslinking agent, filler, plasticizer, and other additives. The properties of the four compounded materials were investigated with the contents of fire retardant, silane coated aluminum hydroxide (S-ATH). Rheology, Mooney viscosity, and tensile strength increased with S-ATH contents by reinforcing effect. With increasing fire retardant amount, fire resistance increased, but cold resistance didn't show an obvious enhancement due to polar effect of vinyl acetate in EVA.

• Korean Journal of Food Science and Technology
• /
• v.53 no.1
• /
• pp.63-71
• /
• 2021

In this study, a comparative analysis was carried out between the 'Beta Tiny' and 'TY Nonari' cherry tomato cultivars harvested at the pink and red stages. Samples of the red stage were stored at room temperature for 9 days, during which physicochemical qualities, antioxidant compounds, and activities were measured. As cherry tomato ripening and storage progressed, firmness was reduced, whereas the lycopene content increased. Total phenolic content and antioxidant activity showed no significant changes as ripening and storage progressed; however, total flavonoid content of 'Beta Tiny' showed a significant increase (p<0.05). The main polyphenols in the two cultivars were identified as chlorogenic acid, rutin, and (-)-epigallocatechin gallate, among which chlorogenic acid showed a significant decrease (p<0.05) as ripening and storage progressed. A strong correlation was found between total phenolic and flavonoid content (R=0.744), and ABTS radical scavenging activity (R=0.975). Additionally, a negative correlation was shown by lycopene and chlorogenic acid (R= -0.934).