• Journal of Microbiology and Biotechnology
• /
• v.8 no.3
• /
• pp.197-202
• /
• 1998

Aliphatic alkenals having 6 to 13 carbons were evaluated for antifungal activity against Saccharomyces cerevisiae. The activity was gradually increased with chain length, e.g., (E)-2-decenal and (E)-2-undecenal exhibited maximum potency, while (E)-2-dodecenal and (E)-2-tridecenal were completely inactive. Alkenals showed increasing inhibitory activity with chain length, as in the case of antifungal activity, towards glucose-induced medium acidification by the plasma membrane $H^+$-ATPase of S. cerevisiae. The group including (E)-2-nonenal, (E)-2-decenal, and (E)-2-undecenal exhibited maximum potency, but the potency of (E)-2-dodecenal and (E)-2-tridecenal demonstrated a sudden drop with respect to the former group. (E)-2-Nonenal revealed dose-responsive inhibition to the medium acidification and inhibited over 90% at a concentration of 1.25 mM ($175.3{\mu}g$/ml). In contrast to (E)-2-undecenal whose inhibitory efficiency increased with incubation time, inhibition by (E)-2-dodecenal was reversed with time. Of the tested alkenals, (E)-2-heptenal and (E)-2-octenal most highly inhibited ATP hydrolytic activity by the plasma membrane $H^+$ ATPase, while (E)-2-heptenal at 10 mM ($1121.8{\mu}g$/ml) showed an inhibitory efficacy of 93.2%.

• Korean Journal of Pharmacognosy
• /
• v.44 no.2
• /
• pp.168-175
• /
• 2013

Aldose reductase (AR) plays a central role in the development of the diabetic complications. Eighty one Korean herbal medicines have been investigated for inhibitory activities on AR. Among them, fourteen herbal medicines exhibited a significant inhibitory activity compared with 3,3-tetramethyleneglutaric acid (TMG) as positive control. Particularly, Xanthium strumarium (fruit, whole plant), Ilex cornuta (stem and leaf), Vitex rotundifolia(stem), Sophora flavescens (whole plant), Platycarya stobilacea (flower) showed two times more potent inhibitory activity than 3,3-tetramethyleneglutaric acid (TMG).

• Korean Journal of Pharmacognosy
• /
• v.45 no.4
• /
• pp.359-365
• /
• 2014

Aldose reductase (AR) is the key enzyme of the polyol pathway in the development of the diabetic complications. Sixty seven Chinese herbal medicines have been investigated for inhibitory activities on AR. Among them, 7 herbal medicines, Buddleja crispa (twigs and leaves), Taiwania flousiana (twigs and leaves), Sloanea hemsleyana (fruits), Euphorbia nemetocypha (whole plants), Photinia glomerata (twigs and leaves), Vitex yunnanensis (twigs and leaves) exhibited a significant inhibitory activity against AR. Particularly, S. hemsleyana and V. yunnanensis showed 1.2-4.5 times more potent inhibitory activity than the positive control, 3,3-tetramethyleneglutaric acid (TMG).

• Applied Biological Chemistry
• /
• v.29 no.2
• /
• pp.207-211
• /
• 1986

Lactic acid bacteria isolated from Kimchi were tested for inhibitory activity against E. coli, Streptococcus faecalis and Lactobacillus bulgaricus. The inhibitory strains appeared most frequently around the middle stage of fermentation during two weeks of observation, and the majority of them were identified as Pediococcus cerevisiae. The agent(s) responsible for the inhibitory activity of P. cerevisiae was inactivated by heat treatment at moderate temperature, but resistant to proteolytic enzymes. The production of the inhibitory compound(s) decreased when the pH of the medium was maintained at about 7 with phosphate buffer.

• Natural Product Sciences
• /
• v.7 no.2
• /
• pp.33-37
• /
• 2001

Methanol extracts of eighty Chinese medicinal plants were investigated for platelet-activating factor (PAF) receptor binding inhibitory activity using rabbit platelet. Extracts of Cratoxylon ligustrinum, Kalimeris indica, Euonymus japonica, Ophiopogon japonicus, Gleditsia sinensis, Clausena lansium, Agave sisalana were found to exhibit significant inhibitory effects. Chloroform partition of the Methanol extract of Kalimeris indica was further fractionated by column chromatography to afford one strong active subfraction with 93.6% inhibition at a concentration of $100{\mu}g/ml$.

• Natural Product Sciences
• /
• v.18 no.1
• /
• pp.22-25
• /
• 2012

Five triterpenoids, epifriedelanol (1), friedelin (2), lupeol (3), ${\beta}$-sitosterol (4), daucosterol (5), and one phenyl propanoids ester, trans-docosanoyl ferulate (6) were isolated from the whole parts of Portulaca oleracea. They were determined using a combination of spectroscopic analyses ($^1H-$, $^{13}C$-NMR, and MS data) and evaluated for their cyclooxygenase inhibitory activity. Compound 6 exhibited inhibitory effect with $IC_{50}$ values of $40.2{\mu}M$ and 1.6 mM on COX-1 and COX-2 activities, respectively.

• Journal of Plant Biology
• /
• v.33 no.4
• /
• pp.309-314
• /
• 1990

Effect of mannose on auxin-induced ethylene production in corn (Zea mays L.) coleoptiles was studied. Auxin induced ethylene production decreased in proportion to mannose concentrations. The inhibitory effect of mannose appeared after 2 h of incubation. Ethylene production was significantly depressed by mannose at high concentration (10-5M-10-4M) of indole acetic acid (IAA), but not at low concentrations (10-8M-10-6M). The inhibition of auxin-induced ethylene production by mannose was specific, since other sugars such as galactose, glucose, sucrose and mannitol did not have an inhibitory effect. In an effort to elucidate mechanisms of mannose the effect on the auxin induced ethylene production, effect of the sugar on ACC synthase activity and ACC induced ethylene production was studied. Mannose failed to inhibit ACC mediated ethylene production, but decreased both the ACC content and ACC synthase activity in the tissue. These results suggest that the inhibitory effect of mannose on auxin induced ethylene production results from suppression of auxin induction of ACC synthase.

• Natural Product Sciences
• /
• v.9 no.1
• /
• pp.34-37
• /
• 2003

We examined methanol extracts prepared from the Korean plants for their inhibitory effects on rat lens aldose reductase (RLAR) activity in vitro. Among 41 plant extracts, the extracts of Lagerstroemia indica, Punica granatum, Eurya japonica, Liquidambar styraciflua, and Vitis coignetiae exhibited highest inhibitory potency, even more potent than tetramethylene glutaric acid (TMG), known as one of typical aldose reductase inhibitors $(IC_{50}\;value,\;0.51\;{\mu}g/ml)$. Especially, the extract of Lagerstroemia indica (Lythraceae), exhibited the most inhibitory potency $(IC_{50}\;value,\;0.069\;{\mu}/ml)$ on RLAR.

• The Korean Journal of Food And Nutrition
• /
• v.5 no.1
• /
• pp.7-12
• /
• 1992

This study was devised to observe the inhibitory effect of 7 kinds PG(PG1, PG2, PG3, PG4, PG5, PG6 and PG7) and of 5 kinds PG4(PG41, PG42, PG43, PG44 and PG45) of the acidic polysaccharide fraction from Korean red ginseng on a lipolytic action of Toxohormone-L. Toxohormone-L is a lipolytic factor, found in ascites fluid. of sarcoma-180 bearing mice and of patients with hepatoma. A substance that inhibited the lipolytic action of toxohormone-L was isolated from red ginseng powder. This substance was an acidic polysaccharides In vitro test showed that the inhibitory effect of PG4 and PG43 fraction of the lipolysis by Toxohormone-L was highest percent among other treatments at concentration of 50, 100, 200, 500 and 1,000ug/ml of reaction mixture. And total inhibitory activity(units) of PG1 and PG4, and PG4 s was highest among other treatments at the same concentration.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1998.11a
• /
• pp.187-187
• /
• 1998

The objective was to verify biological activities of fruit and stem of prickly pear(Opuntia ficus indica L. var, saboten Makino). We have determined inhibitory activities on enzymes, such as dopamine ${\beta}$-hydroxylase(DBH), monoamme oxidase A and B(MAO-A, B), and antioxidant activity, in vitro. We purchased dried stem powder and lyophilized fruit powder of prickly pear from CheJu Island, and prepared the extracts with 80% of methanol. The fruit extract showed stronger inhibitory effects on MAO-A and -B and antioxidant activity compared. to the stem extract, on fractionation with hexane, ethyl acetate, butanol and water. Both the stem and the fruit extracts with ethyl acetate showed stronger enzyme inhibitory and antioxidant activities than other extracts. Now we are isolating active principles from both ethyl acetate extracts.