• Applied Biological Chemistry
• /
• v.39 no.4
• /
• pp.265-267
• /
• 1996

The methanol extracts of AraIia elata showed antimicrobial activity against bacteria. The antimicrobial active principle was successively purified with solvent fractionation, silica gel adsorption column chromatography, Sephadex LH-20 column chromatography, silica gel partition column chromatography and HPLC. The active substance was isolated by HPLC on $C_{18}$ column with an acetic acid-MeOH system. The active substance was identified as trans-4-hydroxycinnamic acid by MS, $^1H-NMR\;and\;^{13}C-NMR$.

• Microbiology and Biotechnology Letters
• /
• v.3 no.2
• /
• pp.63-68
• /
• 1975

A biological active substance was isolated from the cultured medium of Streptomyces sp. and its biochemical characteristics were investigated. Isolation process of the substance was as follows; the pH of filterate of the cultured medium was adjusted to 3.0 with N-hydrochloric acid and saturated with sodium chloride, then chloroform was added to this filterate in one fifth portions and stirred vigorously. After extracting the active substance with chloroform in 3 stages, the chloroform layer combined and evaporatea after dehydrating with sodium sulfate. The substance was found to be to be toxic to various fresh water fishes; the lethal dose for an average size Pseudorasbora parva T. et. S. was 50ug per ml. In the acidic condition, the toxicity of the substance remained fora long time, while in the alkaline state, the toxicity was decreased very fast. This substance was found to be stable to organic solvents, but labile to heat treatment. The maximal revival time of Pseudorasbora parva T. et. S. was about 20 minutes in 25 ug/ml of the substance solution.

• Microbiology and Biotechnology Letters
• /
• v.14 no.2
• /
• pp.145-153
• /
• 1986

For the inactivation of venoms, the chemical methods are generally applied. In the chemical method many works have been carried out with the chemical reagents and immunological antiserums. However, all inhibitory effect of these chemicals acting on snake venomes may well be due not to the specific, but to the nonspecific inhibitory action. Therefore, it is necessary to separate venom into its compositional active proteins and develop specific inhibitor which acts on the each protein. Until now, there have not been any reports about the substance which acts on snake venom as a specific inhibitor. Recently in 1979, we had actually isolated a specific venom inhibitor(ISV) which has a strong inhibitory activity against the proteinase of snake venom of Colubridae. In our experiments described here, a strain of Aspergillus sp., isolated from soil, was able to produce a biological active substance. The partial crystallized substance had a strong inhibitory activity against hemorrhagic action of snake venom of Colubridae. For the inhibitory action of the sample on the lethality of venom, the substance prevented completely the lethal action of the hemorrhagic factor when they were treated with enough amount of the substance. The edema factor of whole venom of Agristrodon bromohoffi brevicaudus was completely inhibited, but those of HR-I and HR-II of Trimeresurus flavoviridis venom were inhibited about 50%, when they were treated with the substance of half amount of venom. On the other hand, from the result of subcutaneous hemorrhage in a rabbit, it was concluded that two kinds of antihemorrhagic substance might be produced by the strain used in this work.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.45 no.1
• /
• pp.17-21
• /
• 2022

The present study aimed to determine whether a hemolymph prepared from Antheraea yamamai larvae had the same biological activities using a Bombyx mori hemolymph prior to exposure to lipopolysaccharide (LPS) in order to induce an inflammatory response. The effects of the hemolymph were determined using a reverse transcription-quantitative polymerase chain reaction to assess the expression of pro-inflammatory molecules. The A. yamamai hemolymph exerted anti-inflammatory effects on LPS-activated human monocytic leukemia cells via Toll-like receptor (TLR) 4-mediated suppression, similar to the B. mori hemocyte extract. Treatment with the A. yamamai hemolymph significantly suppressed LPS-induced upregulated inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA expression at all tested concentrations compared with the control, similar to the B. mori immune-challenged hemolymph. Finally, the A. yamamai hemolymph, like the B. mori immune-challenged hemolymph, suppressed all of these concentrations in a dose-independent manner. These results demonstrate that the hemolymph of A. yamamai exhibited important biologically active substances. Further in-depth functional studies are required to fully understand the mechanisms underlying the biological activities of wild-type silkworm hemolymphs.

• Microbiology and Biotechnology Letters
• /
• v.6 no.4
• /
• pp.187-196
• /
• 1978

Antimetabolite N-2292 substance, an antagonist of L-aspartic acid and L-glutamic acid was isolated from the fermentation broth of Streptomyces. Taxonomical study on the producing strain made it a related species of Streptomyces albulus judged by cultural characteristics and carbon utilization. N-2292 substance was isolated as amorphous white powder with melting point at 185$^{\circ}C$. From the physicochemical characteristics of the substance, it was peptide like substance. It was active against Gram positive and Gram negative bacteria but negative against yeast and mold in its biological properties. It was reversed by L-Asp and L-Glu on the synthetic medium.

• Microbiology and Biotechnology Letters
• /
• v.3 no.2
• /
• pp.69-72
• /
• 1975

Isolation of the toxic substance which was produced by Streptentyces sp. and it's biorhemical characterestics and toxicity to fishes were reported in the previous paper. The present report includes antibiotic activity of the substance, inhibitory activity of the substance on the succinic dehydrogenase of fishes, and its effect on the blood corpuscles of a rabbit. An evident antibiotic activity of this substance was observed on Candida yeasts, but n$ot^1$on molds or bacteria. The substance inhibited the growth of Candida japonica and C. utilis to the 50％ at the concentrations of 7.5 and 10.2ug per ml, respectively. The activity of succinic dehydrogenase obtained from various organs of Cyprinous carpio L. was also found to be inhibited by this substance. Original activities of the enzymes from tht brain, kidney, and liver, were inhibited by 75.4％, 38.2％, and 26.2％, respectively, but not the enzymes from the heart and spleen. Neither leukopenia nor leukocytosis was detected after the intravenous administration of the substince to the rabbit at the level of 6 mg per 2 kg body weight.

• The Plant Pathology Journal
• /
• v.23 no.3
• /
• pp.180-186
• /
• 2007

The biocontrol agent, Serratia plymuthica A21-4, has been developed for controlling pepper Phytophthora blight. Serratia plymuthica A21-4 strongly inhibits the mycelial growth, zoospore formation, and cyst germination of Phytophthora capsici in vitro. The application of a cell suspension of strain A21-4 to pepper plants in pot experiments and in greenhouse successfully controlled the disease. The bacteria produced a potent antifungal substance which was a key factor in the suppression of Phytophthora capsici. The most active chemical com-pound was isolated and purified by antifungal activity-guided fractionation. The chemical structure was identified as a chlorinated macrolide $(C_{23}H_{31}O_8Cl)$ by spectroscopic (UV, IR, MS, and NMR) data, and was named macrocyclic lactone A21-4. The active compound significantly inhibited the formation of zoosporangia and zoospore and germination of cyst of P. capsici at concentrations lower than $0.0625{\mu}g/ml$. The effective concentrations of the macrocyclic lactone A21-4 for $ED_{50}$ of mycelial growth inhibition were $0.25{\mu}g/ml,\;0.25{\mu}g/ml,\;0.30{\mu}g/ml \;and\;0.75{\mu}g/ml$ against P. capsici, Pythium ultimum, Sclerotinia sclerotiorum and Botrytis cinerea, respectively.

• Microbiology and Biotechnology Letters
• /
• v.15 no.2
• /
• pp.129-134
• /
• 1987

Aspergillus sp. (MK-24) producing a biological active substance that inhibited the venom proteinase activity was isolated from soil. The substance also inhibited the activity of trypsin and coagulation of blood, but did not inhibit papain, $\alpha$-chymotrypsin and pepsin. The substance was partially purified from culture filtrate by precipitaion with acetone, and by chromatography of DEAE-Sepadex A-50 column and Amberlite IRC-50 ion exchange. The inhibitory substance was stable in the wide pH range from 2.0 to 12.0 at 37$^{\circ}C$, but not stable at $65^{\circ}C$ in the alkaline pH. Only 12% of the activity was decreased by the heat treatment at 10$0^{\circ}C$ for two hours. The inhibition on venom proteinase (Agkistrodon bromohoffi brevicaudus) was a mixed type. The inhibitory activity depended on the preincubation time and completely depressed by cupric, zinc and cobalt ions. The inhibition on the venom proteinase was appeared strongly on casein but not on ovalbumin or hemoglobin as a substrate.

• Korean Journal of Agricultural Science
• /
• v.11 no.1
• /
• pp.53-60
• /
• 1984

The followings are the results obtained from the investigation of isolation and cultural conditions of a fungus producing antibiotic from humus, spring soil, paddy, field and etc. 1. Among fungi which were capable of antimicrobial sub stance producing at the $45^{\circ}C$, Strain H-3 was selected as test st rain because of its efficiency in antimicrobial substance producing. 2. Strain H-3 was identified as a Aspergullus fumigatus by the mophological properties. 3. The compositions of optimun media for the production of antimicrobial substance were followed;glucose 20g, $NaNO_3$ 3g, $K_2HPO_4$ 1g, $CaCl_2$ 0.5g, $MgSo_4$ 0.5g, $FeSO_4$ 0.005g. 4. Optimum culture conditions were founded to be pH 5.0, $40^{\circ}C$ respectively. 5. The maximum antimicrobial substance producing obtained in this study was showed 14mm of clear zone after 72 hrs incubation under the optimum conditions. 6. AF-c substance was active against Gram-positive, Gram-negative bacteria, and yeast but not mold in its biological properties.

• Applied Biological Chemistry
• /
• v.41 no.8
• /
• pp.613-615
• /
• 1998

Antithrombotic function of doenjang was investigated using thoroughly desalted aqueous extract. In the presence of the extract, thrombin suffered loss of its fibrin-clotting activity, whose extent increased in a dose-dependent manner. The active substance involved in thrombin inhibition showed a high thermal stability. Results of Sephadex G-25 permeation chromatography indicated that there were at least two soluble thrombin inhibitors in doenjang with different molecular sizes.