• Journal of Plant Biology
• /
• v.37 no.4
• /
• pp.397-402
• /
• 1994

Possible roles of polyamines in the inhibition of cell elongation in Ranunculus petioles were investigated. Exogenously apoplied polyamines greatly inhibited the auxin-induced petiole growth, while treatment of the tissue with $\alpha$-difluoromethylarginine, the inhibitor of putrescine biosynthesis, further enhanced the growth in the presence of IAA. Inhibitory effect of spermine can also be apparent for fusicoccin-induced elongation, but not for growth induced by a low pH. Spermine also suppressed the ethylene-enhanced growth in the presence of auxin. Using computer-based video digitizer system, the inhibitory effects of spermine on petiole growth were kinetically analyzed. Auxin-induced growth was characterized by an initial and transient growth with a highly elevated rate followed by a steady growth with a slightly reduced rate. Spermine treatment was found to shorten the duration of the initial phase of growth, and to reduce the rates of both the initial and steady growth as well. The latent period for auxin induction was not affected by spermine.

• Journal of Korean Society of Water and Wastewater
• /
• v.11 no.3
• /
• pp.124-130
• /
• 1997

Wastewater containing phenol was treated using Pseudomonas sp. B3 in continuous reactor, reaction characteristics and kinetics according to variation of volumetric loading rate in continuous reactor were studied. The removal efficiencies of phenol were more than 99% at the whole range of experiment, and those of COD were 97% at the volumetric loading rate, $0.96kg/m^3{\cdot}d$ and 88% at $3.0kg/m^3{\cdot}d$, respectively. Kinetics constants of $q_m$, $K_s$, Y and $K_d$ were obtained 0.901 l/d, 0.620mg/l, 0.659 and 0.219 l/d, respectively. As compared with to constants of standard activated sludge process, these constants were remarkably different because of toxicity and inhibition of phenol to microbes. And also, kinetics constants of oxygen utilization, a, and b, were shown 0.384 kg $O_2/kg$ phenol and 0.029 l/d.

• Bulletin of the Korean Chemical Society
• /
• v.21 no.11
• /
• pp.1085-1089
• /
• 2000

The effect of 2-hydroxyacetophenone-aroyl hydrazone derivatives on the inhibition of copper corrosion in 3N nitric acid solution at 303 K was investigated by galvanostatic polarization and thermometric techniques. A significant decrease in the cor rosion rate of copper was observed in the presence of the investigated compounds. The corrosion rate was found to depend on the nature and concentrations of the inhibitors. The degree of surface coverage of the adsorbed inhibitors is determined from polarization measurements, and it was found that the results obey the Frumkin adsorption isotherm. The inhibitors acted as mixed-type inhibitors, but the cathode is more polarized. The relative inhibitive efficiency of these compounds has been explained on the basis of structure dependent electron donor properties of the inhibitors and the nature of the metal-inhibitor interaction at the surface. Also, some thermodynamic data for the adsorption process ( ΔGa* and f ) are calculated and discussed.

• Journal of Photoscience
• /
• v.9 no.2
• /
• pp.158-161
• /
• 2002

UV-B radiation gives harmful effects on plants, such as production of several types of DNA lesions, and growth inhibition. On the other hand, plants have some protective mechanisms, including filtering effect due to accumulation of phenolic compounds in epidermal cells and reactivation of DNA lesions, which are enhanced by UV-B irradiation. We have investigated the mechanism of UV-B effects on plants using cucumber seedlings as plant materials. Cucumber plants were cultivated in an artificially lit growth chamber. Supplemental UV-B irradiation, of which intensity was almost equal to the level of natural sunlight, retarded the growth of first leaves. The growth retardation must result trom the inhibition of cell division and/or cell growth. Microscopical observation of leaf epidermis suggested that the growth retardation might be mainly caused by cell growth inhibition. The retardation was, however, restored within 2 or 3 days after the termination of UV-B irradiation. It is known that UV-B irradiation lowers the activity of photo system II (PS II). In the present experimental conditions, however, UV-B irradiation has little effect on PS II activity as estimated by chlorophyll fluorescence. The stomatal conductance, a major factor determining photosynthetic rate, of first leaves increased during the growth. The increase of stomatal conductance was suppressed by UV-B irradiation and restored by termination of the irradiation. It has not been clear, however, what mechanisms are involved in the suppression of increase of stomatal conductance.

• Korean Journal of Plant Resources
• /
• v.25 no.6
• /
• pp.670-681
• /
• 2012

Herb extracts commercially used in Korea were screened for PPAR-${\gamma}$ agonist test and ${\alpha}$-glucosidase inhibition assay. Total 16 herb plants had a PPAR-${\gamma}$ agonist activity. Specially, Alisma orientale Juz (108.41%), Ephedra sinica (98.22%), Sasa japonica Makino var. purpurascens Nakai (140.68%), Astragalus membranaceus Bunge (106.79%) and Cnidium officinale Makino (113.00%) showed high PPAR-${\gamma}$ agonist activity rate compared with rosiglitazone's (167.46%). And Cornus officinalis S. et Z. (90.3%), Cinnamomum cassia Blume (89.2%), Psoralea corylifolia L. (89.8%), Paeonia japonica (Makino) Miyabe (92.4%) and Paeonia suffruticosa Andr (93.2%), showed high ${\alpha}$-glucosidase inhibition rates. These results support previous reports of the efficacy of Oriental medicinal plants used for diabetes mellitus.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.2
• /
• pp.375-383
• /
• 2000

A mixed culture isolated from petroleum-contaminated soil was enriched on toluene as a sole carbon and energy source, and degradation characteristics of BTEX(Benzene, Toluene, Ethylbenzene, Xylenes) was observed. In the single-substrate experiments, all the BTEX compounds were degraded, and it was degraded as following orders; toluene, benzene, ethylbenzene, and p-xylene. In the degradation experiments of BTEX mixtures, the degradation rate was decreased compared to that in the single substrate experiment and ethylbenzene was degraded faster than benzene. In the experiments of binary-mixtures, various substrate interactions such as inhibition, stimulation, and non-interaction were observed, and ethylbenzene was shown to be most potent inhibitor of BTEX degradation. In the degradation characteristic studies of xylene isomers, m-xylene and p-xylene were degraded as carbon sources, and it was stimulated in the presence of either benzene or toluene. However, degradation of o-xylene was enhanced only in the presence of benzene.

• Journal of the Korean Chemical Society
• /
• v.52 no.2
• /
• pp.124-132
• /
• 2008

effect of some furfural hydrazone derivatives (I -V) as corrosion inhibitors for C-steel in 3M H3PO4 solution in which M indicates mol/l has been studied using weight-loss and galvanostatic polarization techniques. A significant decrease in the corrosion rate of C-steel was observed in the presence of the investigated compounds. This study revealed that, the inhibition efficiency increases with increasing the inhibitor concentration, and the addition of iodide and thiocynate ions enhances it to a considerable extent. The effect of temperature on the corrosion behavior of C-steel was studied in the range from 30-60oC with and without 510-6 M investigated compounds using weight-loss method. Apparent activation corrosion energy (Ea*) and other thermodynamic parameters for the corrosion process were calculated and discussed. The polarization measurements show that the investigated compounds act as mixed-type inhibitors, but the cathode is more polarized when an external current was applied. The adsorption of these compounds on the surface of C-steel in 3M H3PO4 obeys Frumkins adsorption isotherm. The mechanism of inhibition was discussed in the light of the chemical structure of the investigated compounds.

• The Korea Journal of Herbology
• /
• v.20 no.4
• /
• pp.17-26
• /
• 2005

Objectives : Antioxidant, Anticancer and Antibacterial Activities of Naesohwangryntang and its composition oriental medicines. Methods : We were experimented anti-oxidation effect and growth inhibition ability on cancer cells and antibacterial activity on various kinds of bacteria of skin. Results : The results were obtained as follows : Electron donating ability(EDA) of water extract Naesohwangryntang and ethanol extract Naesohwangryntang was 60% and 70% at 1000 ppm concentration. In the test of SOD-like activity, ethanol extract showed more activity with 27.4% in 700 ppm, while water extract was low in 19.6%. Clear zones formed by sample against the human skin-resident microflora indicated that anti-microbial activity of ethanol extract Naesohwangryntang was higher than that of water extract Naesohwangryntang. The growth inhibition rates of each sample on lung-cancer(A549), at 1000 ppm cancer cell was over 40%. The growth inhibition rate of the each sample melanoma-cancer(B16F10, G361), at 1000 ppm was over 80%. Conclusions : The results indicated that, ethanol extract which is superior in its anti-oxidation and antibacterial effect is useful to be applied in cosmetic industry.

• Journal of Pharmacopuncture
• /
• v.22 no.4
• /
• pp.231-238
• /
• 2019

Objectives: Alzheimer's disease (AD), an overwhelming neurodegenerative disease, has deleterious effects on the brain that consequently causes memory loss and language impairment. This study was intended to investigate the neuroprotective activity of the two essential oils (EOs) from Iranian Pistacia khinjuk (PK) leaves and Allium sativum (AS) cloves against β-Amyloid 25-35 (Aβ25-35) induced elevation of cholinesterase enzymes in AD. Methods: The EOs of PK (PKEO) and AS (ASEO) were prepared and analyzed in terms of extraction yield, phenolic content, and cholinergic markers in vitro. Moreover, both were administered orally to adult male Wistar rats at concentrations of 1, 2, and 3%. The inhibitory potential of PKEO and ASEO was compared with Donepezil (0.75 mg/kg) against the high activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Results: PKEO reached an inhibition rate of 83.6% and 81.4% against AChE and BChE, respectively. ASEO had lower anti-cholinesterase activity (65.4% and 31.5% for the inhibition AChE and BChE). PKEO was found to have more phenolic content than ASEO. A significantly positive correlation was observed between the total phenolics and anti-cholinesterase potential. In rats, both EOs decreased the enzyme activity in a concentration-dependent manner. As compared with Donepezil, the significant difference in the AChE and BChE inhibition occurred as rats were treated with PKEO 3% (p < 0.05). Conclusion: It could be concluded that PKEO and ASEO are potent inhibitors of AChE and BChE in rats that hold promise to be used for the treatment of AD.

• Natural Product Sciences
• /
• v.21 no.2
• /
• pp.104-110
• /
• 2015

The activities on the inhibition of NO on LPS-induced RAW 264.7 macrophages were investigated in this work. A simple and sensitive method has been developed and validated for fingerprinting analysis of leaves of Acanthopanax gracilistylus W.W. Smith (AGS). The cytotoxicity and inhibition of NO on LPS-induced RAW 264.7 cells of the extract and triterpenoids were determined. Optimal conditions of HPLC analysis were established as follows. The separation was performed with an ODS-C₁₈ column at $30^{\circ}C$, the detected wavelength was 210 nm, the flow rate was 1 mL/min, and the mobile phase consisted of acetonitrile (0.05% phosphoric acid)-0.05% phosphoric acid solution with gradient elution. Our results showed that impressic acid and acankoreaogenin was more effective on the inhibition of NO than the methanol extract and other compounds. There were seventeen peaks coexisted with similarities above 0.95 and nine lupane-triterpenoids including acankoreaogenin and impressic acid detected and identified. The result of anti-inflammatory activities provides a potential explanation for the use of AGS leaves as a herbal medicine in the treatment of inflammatory diseases. Our results also show that acankoreanogenin and impressic acid may be potentially useful in developing new anti-inflammatory agents. In addition, the fingerprint chromatography clearly illustrated and confirmed the material basis for the anti-inflammatory activities of this plant.