• Journal of Wetlands Research
• /
• v.19 no.4
• /
• pp.443-450
• /
• 2017

The objective of this study was to isolate algae growth inhibiting microorganism to biologically control Microcystis aeruginosa, which is a harmful cyanobacterium. Various bacterial strains were isolated in this study, and four bacterial strains of M1~M4 exhibited remarkable growth inhibiting activity against M. aeruginosa. Based on the 16S rRNA analysis, the isolated M1~M4 strains were identified, and isolated four strains were rod-type and gram-negative. In particular, as well as respective single strain, co-culture of the isolated M1~M4 strains showed obvious algicidal activity against M. aeruginosa. When mixed four strains were inoculated, about 50% of the chlorophyll a was reduced after two days, about 70% after four days, and about 80% after seven days. From these results mentioned above, the four bacterial strains may contribute to the control of harmful M. aeruginosa.

• Journal of Applied Biological Chemistry
• /
• v.42 no.4
• /
• pp.202-204
• /
• 1999

Methanol extracts of leaves from 15 Pinus species belonging to the family Pinaceae were tested for their in vitro growth-inhibiting activities against 10 bacteria commonly found in the gastrointestinal tracts of human, using impregnated paper disk methods. The inhibitory activities varied with both bacterial strain and Pinus species used. At a concentration of 10 mg/disk, a clear growth inhibition was produced from the extracts of Pinus armandii, P. banksiana, P. bungeana, P. densiflora, P. rigida, and P. thunbergii against Clostridium perfringens, whereas all Pinus samples revealed weak or little growth-inhibiting activity against Escherichia coli, Bacteroides fragilis, and Staphylococcus aureus. At 5 mg/disk, the extracts of P. banksiana and P. thunbergii exhibited potent growth inhibition toward C. perfringens. All the extracts except the one from P. densiflora did not adversely affect growth of Bifidobacterium adolescentis, B. longum, B. bifidum, B. breve, B. animalis, and Lactobacillus casei. The growth-inhibiting activity was more pronounced in C. perfringens, as compared to the lactic acid-producing bacteria. These results may be an indication of at least one of the pharmacological activities of these Pinus species.

• The Korean Journal of Physiology and Pharmacology
• /
• v.2 no.2
• /
• pp.251-260
• /
• 1998

Cromakalim (BRL 34915), known as an airway smooth muscle relaxant, inhibited the releases of mediators in the antigen-induced mast cell activation. It has been suggested that cromakalim, in part, inhibited mediator releases by inhibiting the initial increase of 1,2-diacylglycerol (DAG) produced by the activation of the other phospholipase system which is different from phosphatidylcholine-phospholipase D pathway. The aim of this study is to further examine the inhibitory mechanism of cromakalim on the mediator release in the mast cell activation. Guinea pig lung mast cells were purified by using enzyme digestion and percoll density gradient. In purified mast cells prelabeled with $[^3H]PIP_2$, phospholipase C (PLC) activity was assessed by the production of $[^3H]$insitol phosphates. Protein kinase C (PKC) activity was assessed by measuring the protein phosphorylated from mast cells prelabeled with $[{\gamma}-32P]ATP$, and Phospholipase $A_2\;(PLA_2)$ activity by measuring the lyso-phosphatidylcholine produced from mast cell prelabeled with 1-palmitoyl-2-arachidonyl $phosphatidyl-[^{14}C]choline$. Histamine was assayed by fluorometric analyzer, and leukotrienes by radioimmunoassay. The PLC activity was increased by activation of the passively sensitized mast cells. This increased PLC activity was decreased by cromakalim pretreatment. The PKC activity increased by the activation of the passively sensitized mast cells was decreased by calphostin C, staurosporine and cromakalim, respectively. The $PLA_2$ activity was increased in the activated mast cells. The pretreatment of cromakalim did not significantly decrease $PLA_2$ activity. These data show that cromakalim inhibits histamine release by continuously inhibiting signal transduction processes which is mediated via PLC pathway during mast cell activation, but that cromakalim does not affect $PLA_2$ activity related to leukotriene release.

• Research in Plant Disease
• /
• v.26 no.2
• /
• pp.61-71
• /
• 2020

With 32 fungicides, it was examined the inhibitory effects on the mycelial growth of Alternaria dauci KACC42997 causing Alternaria leaf blight of carrot. Showing the results of the agar dilution method, the fungicides belonging to C2, C5, G1, E2, and E3 group were excellent in inhibiting mycelial growth. Protective fungicides belonging to M group, except for iminoctadine tris-albesilate, and pyraclostrobin belonging to C3 group were effective in inhibiting spore germination of pathogens. The fungicides included into C2 group inhibiting succinate dehydrogenase activity and the G1 group inhibiting demethylase activity showed the excellent inhibitory effect on mycelial growth but the inhibitory effect of spore germination was very low. However, fluazinam belonging to C5 group was excellent in inhibiting spore germination as well as mycelial growth. Especially, when 100 ㎍/ml of fluxapyroxad belonging to the C2 group was treated, 47.1% of spore formation was inhibited on the medium. In comparison of the resistance factors of 3 fungicide groups, as G, C, and E group, in populations of A. dauci isolates collected from Gumi, Pyeongchang, and Jeju, resistance factor in the population of Jeju was the lowest. However, two isolates resistant to fludioxonil belonging to E2 group were found in the isolate group of Pyeongchang, and both showed cross-resistance to iprodione and procymidone.

• Applied Biological Chemistry
• /
• v.34 no.3
• /
• pp.287-294
• /
• 1991

The relationships between the quantitative structure of benzotriazoles and their post-emergence growth inhibiting activity$(pI_{50})$ against Oryzae sativa L. and Echinochloa crus-galli were investigated using a generalized quantitative structure activity relationships (QSAR). According to the QSAR analysis, the free radical parameter $(E_R)$ is a very important factor and the growth inhibiting activity values showed parabolic relation to $E_R$ parameter of para-substituents(X). The activity of (3) was superior to those of (4) and (3b) is selected as the most highly effective compound. The optimal values of $E_R$ parameter of the growth inhibiting activity aganist E.crus-galli are $E_R(3)=0.52\;and\;E_R(4)=0.15$, respectively. From the result of molecular design, the substituents(X) of electron withdrawing properties and $E_R$ parameter of optimal value(0.52) were most desirable for high activity of the benzotriazoles. And in view of this, benzotriazoles may also be effective in blocking the photosynthetic electron transfer.

• Korean Journal of Pharmacognosy
• /
• v.40 no.2
• /
• pp.83-88
• /
• 2009

Bone is continuously remodeled by osteoblasts and osteoclasts. Osteoclasts play an important role in bone metabolism by resorbing the bone matrix. Thus, the compounds inhibiting osteoclasts can improve bone diseases such as osteoporosis. The methanol extracts of 159 herbal medicines were screened for the inhibitory activity against differentiation of osteoclasts. Among the tested extracts, Achuranthis Radix and Corydalis Tuber showed relatively strong inhibitory activity against differentiation of osteoclasts, whereas they have no significant effect on proliferation of osteoclasts.

• Microbiology and Biotechnology Letters
• /
• v.25 no.3
• /
• pp.293-297
• /
• 1997

To develope natural food preservatives of pine needle (Pinus densiflora Seib et Zucc.) extract, pine needle sap, ethanol and ether extracts were prepared for investigation of antimicrobial activities against food-related bacteria and yeasts. All extracts exhibited growth inhibiting activities for most of microorganisms tested. However, in general, growth inhibiting activities were higher in ethanol extract than in sap or ether extract. Minimum inhibitory concentrations (MIC) of ethanol extract for Lactobacillus casei, Pseudomonas aeruginosa or Escherchia coli were as low as 0.1 mg/ml, whereas MIC of sap or ether extract for most bacteria and yeasts were 0.25-0.8mg/ml, indicating that the ethanol extract showed the antimicrobial activity by 2.5 $\sim$8 times higher than the sap and ether extract. The antimicrobial activity of the ethanol extract was reduced by heating or alkali treatment. Moreover, growth of Pseudomonas aeruginosa was completely inhibited within 24 hours by the addition of at least 50ppm of ethanol extract. These findings suggest that pine needle, specially the ethanol extrat may play a role for natural food preservatives.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.10
• /
• pp.1585-1590
• /
• 2007

Although a number of melanogenesis inhibitors have recently been reported and used as cosmetic additives, none is completely satisfactory, leaving a need for novel skin-depigmenting agents. Thus, to develop a novel skin depigmenting agent from natural sources, the inhibition of melanogenesis by Chinese plants was evaluated. A methanolic extract of Nigella glandulifera Freyn was found to inhibit the melanin synthesis of murine B16F10 melanoma cells by 43.7% and exhibited a low cytotoxicity (8.1%) at a concentration of $100\;{\mu}g/ml$. Thus, to identify the melanogenesis-inhibiting mechanism, the inhibitory activity towards tyrosinase, the key enzyme of melanogenesis, was further evaluated, and the results showed inhibitory effects on the activity of intracellular tyrosinase yet not on mushroom tyrosinase. Finally, to isolate the compounds with a hypopigmenting capability, activity-guided isolation was performed, and Dioctyl phthalate identified as inhibiting melanogenesis.

• Journal of Haehwa Medicine
• /
• v.10 no.1
• /
• pp.109-114
• /
• 2001

To evaluate the antitumor activity of Paridis Rhizoma(PR), studies were done experimentally. The results were obtained as follows: 1. In cytotoxicity against MCF-7, SK-OV-3, HCT15, concentration inhibiting cell growth up to below 50% of control was recognized at $100-200{\mu}g/m{\ell}$ of PR and also against A549, XF498 was recognized at $50-100{\mu}g/m{\ell}$. 2. In Inhibitory effect on activity of DNA topoisomerase I, the $IC_{50}$ was shown $50-100{\mu}g/m{\ell}$ of PR. 3. The concentration inhibiting adhesion of A549 and SK-OV-3 to complex extracellular matrix up to below 50% of control was recognized at $10-100{\mu}g/m{\ell}$ of PR. 4. The T/C% was 137.9 in PR-treated group in S-180 bearing ICR mice. From above results it was concluded that PR could be usefully applied for the prevention and treatment of cancer.

• Journal of Haehwa Medicine
• /
• v.8 no.1
• /
• pp.131-146
• /
• 1999

To evaluate the antitumor activity of Kamisagoonjatang(KST), Kami-jihwangtang (KJT) and Kamigoonjajihwangtang(KKJT), studies were done experimentally. The results were obtained as follows: 1. In cytotoxicity against B16-F10, HT1080, SNU, and L1210, con-centration inhibiting cell growth up to below 50% of control was recognized at $10^{-3}g/ml$ of KKJT. 2. In cytotoxicity against A549, SK-OV-3, XF498 and HCT15, concentration inhibiting cell growth up to below 30% of control was over $400{\mu}g/ml$ of KKJT only and also over $200{\mu}g/ml$ against SK-MEL-2. 3. In Inhibitory effect on activity of DNA topoisomerase I, the $IC_{50}$ was shown $200-400{\mu}g/m{\ell}$, of KST, over $400{\mu}g/m{\ell}$ of KJT and $100-200{\mu}g/m{\ell}$ of KKJT. 4. The T/C% was 122.8 in KJT, 127.4 in KST and 158.4 in KKJ-Ttreated group in S-180 bearing ICR mice. 5. In hematological changes in S-180 bearing ICR mice, numbers of WBC were decreased significantly in KJT and KKJT treated groups as compared with control, whereas those of platelet were increased with no significance in all groups as compared with control. From above results it was concluded that KKJT could be usefully applied for the prevention and treatment of cancer.