• Mass Spectrometry Letters
• /
• v.4 no.2
• /
• pp.34-37
• /
• 2013

Honokiol and magnolol, the major bioactive neolignans of magnolia officinalis, are the most important constituents of the crude drug prescriptions that are used in the therapy of neuroses and various nervous disorders. There have been limited reports on the effects of neolignoid compounds on human cytochrome P450 activity. Therefore, the inhibitory effects of honokiol and magnolol on seven human cytochrome P450 s were evaluated in human liver microsomes. Honokiol and magnolol showed the most potent inhibition of CYP1A2-mediated phenacetin O-deethylase activity ($IC_{50}$ values of 3.5 and 5.4 mM, respectively) among the seven P450s tested. These in vitro data indicate that neolignan compounds can inhibit the activity of CYP1A2 and suggest that these compounds should be examined for potential pharmacokinetic drug interactions in vivo.

• Korean Journal of Pharmacognosy
• /
• v.28 no.3
• /
• pp.131-137
• /
• 1997

The aqueous and methanolic extracts of 110 crude drugs were screened for hyaluronidase inhibitory activity using a microplate assay. Among them, MeOH extract of 15 crude drugs inhibited more than 80% of hyauluronidase activity at the concentration of 5mg/ml. The active principles of Anemarrhenae Rhizoma, Rhei Rhizoma, Ephedrae Herba, Pteropi Faeces and Ginseng Radix alba were transferred into organic solvents.

• Korean Journal of Pharmacognosy
• /
• v.46 no.1
• /
• pp.1-5
• /
• 2015

In the course of screening tyrosinase inhibitory activity, EtOAc-soluble fraction of Nelumbinis Semen (Seeds of Nelumbo nucifera) showed significant inhibition. Further fractionation of the EtOAc-soluble fraction resulted in 12 compounds, which were identified as 4-(hydroxymethyl)phenol (1), tyrosol (2), 4-(hydroxymethyl)benzaldehyde (3), 4-hydroxybenzoic acid (4), 4-(2-methoxyvinyl)benzene-1,2-diol (5), 2,6-dihydroxybenzoic acid (6), (2R-trans)-2,3-dihydro-3,5,7,8-tetrahydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one (7), (+)-catechin (8), elephantorrhizol (9), (+)-dehydrovomifoliol (10), (-)-boscialin (11) and uridine (12). Compounds 5 and 7 were first reported from this plant. Among the isolated compounds, compound 7 showed strong inhibition on tyrosinase activity with mixed mechanism of competitive and noncompetitive inhibition.

• Archives of Pharmacal Research
• /
• v.21 no.1
• /
• pp.1-5
• /
• 1998

Rebamipide, 2-(4-chlorobenzoylamino)-3-[2(1H)-quinolinone-4-yl]-propionic acid, a novel antipeptic ulcer agent, has been reported to prevent various acute experimental gastric mucosal lesions and to accelerate the healing of chronic ulcers. Therapeutic effect of rebamipide was investigated with regard to the inhibitory effect on xanthine oxidase activity and type conversion of the enzyme which play a profound role in oxygen radicals generation system. Intraperitoneal administration of rebamipide at 60 mg/kg body weight reduced the xanthine oxidase activity, lipid peroxide content in ammonia induced hemorrhagic lesion. These results suggest that the therapeutic effect of rebamipide on gastric mucosal lesion may be in part due to the inhibitory activity of xanthine oxidase and type conversion rate of the enzyme.

• Journal of the Korean Home Economics Association
• /
• v.19 no.2
• /
• pp.183-188
• /
• 1981

This study was conducted to investigate the effects of synthetic antioxidants con the degradation of angiotensin II which is made up of 8 amino acids: Asp-Arg-Val-Try-Ile-Gly-Pro-Phe, by the $\alpha$-chymotrypsin and trypsin. the results obtained were as follow; 1. Dibutyl hydroxytoluene, butyl hydroxyanisole and sodium L-ascorbate showed no inhibitory effect on the activity of $\alpha$-chymotrypsin on the angiotensin II, but ethyl protocathechuate inhibited. its activity at the concentration of 100ppm. However, the angiotension II was gradually degradated by $\alpha$-chymotrypsin after one hour incubation with ethylprotecathechuate. 2. Butyl hydroxyanisole inhibited trypsin activities above 100ppm, but no inhibitory activities was observed by the other antioxidants used in this experiment.

• Journal of Plant Biology
• /
• v.21 no.1_4
• /
• pp.21-27
• /
• 1978

The effect of tannic acid on GAs and cyclic-AMP promoted amylase induction in barley aleurone layers was examined. Of a variety of adenine compounds, only cyclic-AMP and ADP showed significant activity, and these activities were promoted by addition of theophylline to the incubation medium. When aleurone layers of barley endosperm tissues were incubated with GAs in the presence of tannic acid, the amylase activity in the incubation medium was reduced. Cyclic-AMP induced amylase activity was also reduced by additiion of tannic acid. The cyclic-AMP response promoted was more sensitive to tannin inhibition than GAs response. The inhibitory effect of tannic acid shwoed reversibility by addition of higher concentration of GAs or cyclic-AMP. The tannic acid effect on GAs response was also recovered by addition of a higher concentration of cyclic-AMP. Experiment with polyacrylamide disc electrophoresis showed different isozyme patterns according to the additions in the incubation medium. Inhibitory effects of decursinol and coumarin was compared with that of tannic acid. They showed different zymogram patterns.

• Environmental Analysis Health and Toxicology
• /
• v.13 no.3_4
• /
• pp.117-123
• /
• 1998

Paraquat is a useful nonselective herbicide widely used throughout the world. However, accidental or intentional ingestion of the paraquat cause fetal pulmonary injuring. But there is not suitable antidote of paraquat intoxication and therapeutic agents now be used are not effective. So, in this study we intended to evaluate the inhibitory effects of DDB(dimethyl-4,4'dimethoxy-5,6,5',6'-dimethylene dioxyphenyl-2,2'-dicarboxylate) on paraquat toxicity. DDB (100mg/kg) was administered orally to SD rats lhr after paraquat(50mg/kg) injection. After 24 hours, the biochemical parameters of blood and tissues were examined. In paraquat treated groups sGPT, sGOT, BUN, creatinine, MDA and alkaline phosphatase levels in blood and MDA, glucose-6-phosphatase activity in tissues were elevated by 2 to 5 times of normal values. However in schizandrin treated groups, sGPT, sGOT, MDA and alkaline phosphatase activity in blood and MDA and glucose-6-phosphatase activity were significantly decreased to notmal levels but not in biochemical parameters of nephrotoxicity, BUN and creatinine levels. Therefore, we concluded that schizandrin can be used as an antidote of pulmono, hepatotoxicity of paraquat.

• Archives of Pharmacal Research
• /
• v.28 no.2
• /
• pp.169-171
• /
• 2005

The methanolic extract of the aerial parts of Persicaria thunbergii was found to show inhibitory activity on Farnesyl Protein Transferase (FPTase). Bioassay-guided fractionation of the methanolic extract resulted in the isolation of isorhamnetin, as an inhibitor on FPTase. This compound inhibited FPTase activity in a dose-dependent manner, and the $IC_{50}$ value of isorhamnetin was $37.5\;{\mu}M$.

• Archives of Pharmacal Research
• /
• v.19 no.5
• /
• pp.337-341
• /
• 1996

Propolid (bee-glue), known as a folk medicine, is a lipo;hilic material found in honeybee hives. In the present study on the anti-inflammatory effect of Korean propolis, it was extracted with ethanol, and used as a test material. The $LD_{50}$ value with the oral administration of ethanolic extract of Korean propolis (EEKP) was higher than 2g/kg in mice. The oral administration of the propolis extract (100mg/kg) significantly inhibited the development of hind paw edema induced by carrageenin in rats. the oral pretreatment of the propolis extract markedly inhibited the increase in vascular permeability and the number of writhing induced by acetic acetic acid in mice. Propolis extract, 50 and 100 mg/kg p.o. per day for 7 days, produced a significant inhibitory effect on granuloma and exudate formation in rats. This inhibitory effect was enhanced with the concomitant use of prednisolone (2.5 mg/kg). These results suggest that Korean propolis apparently has a strong anti-inflammatory activity.

• Archives of Pharmacal Research
• /
• v.29 no.1
• /
• pp.64-66
• /
• 2006

The methanolic extract of the aerial parts of Centipeda minima was found to show inhibitory activity on farnesyl protein transferase (FPTase). Bioassay-guided fractionation of the methanolic extract resulted in the isolation of 6-O-angeloylprenolin, as an inhibitor on FPTase. This compound inhibited FPTase activity in a dose-dependent manner, and the $IC_{50}$ value of 6-O-angeloylprenolin was 18.8 ${\mu}M$.