• Korean Journal of Microbiology
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• v.33 no.2
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• pp.131-135
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• 1997

Several microorganisms capable of producing protopectinase, which catalyzes dissociation of plant tissue to single cells, were isolated from soils. Crude enzymes prepared from culture supernatants of the strains released potato cells as a single cell from potato tissues. One of the isolated strains showing higher activity of protopectinase was selected and identified as Rhizopus sp. from the morphological characteristics. For preparing single cells from potato tissues, optimum enzyme activity of protopectinase, which was prepared from culture filtrate of Rhizopus sp. R2, was obescrved at $40^{\circ}C$ and pH 4.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.466-471
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• 1996

The survey on the chitinolytic activity of some plants was performed for the purpose of obtaining some reliable and inexpensive sources of chitinase. Rice, soybean for sprouting, kiwi fruit, almond and crude papain were investigated. Rice bran, seed coat of the soybean and the pericarp of kiwi fruit showed a considerable activity, while the bean after the removal of the seed coat, the mixture of rice integument and endosperm, polished rice, and defatted soybean powder didn't have any detectable activity. These crude enzymes have shown to contain both endo- and exochitinase activity. The effects of pH and temperature on the enzyme activity were variable. Furthermore we have observed the chitosanolytic activity from these enzyme Preparations. The rice bran had the highest activity in the enzymatic degradation of chitosan, and seed coat of soybean and the pericarp of kiwi fruit followed. On the basis of the fact that crude papain was not only commercially available but also the most potent in the endochitinase activity and the lowest in the exochitinase activity, we could conclude that crude papain was considered as the most suitable source of the chitinase among plants studied in this paper. In addition, rice bran was worth further investigation from the point of utilizing agricultural by-product.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.304-311
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• 1995

To determine whether chitinolytic enzymes from Chromobacterium violaceum C-61 play an important role in the suppression of Rhizoctonia damping-off, Tn5 insertion mutants deficient in chitinolytic activity (Chi a- mutants) were selected and their chitinolytic and disease suppression were compared with those of the parental strain. Four Chi a- mutants selected from about 2,000 transconjugants did not inhibit mycelial growth of Rhizoctonia solani on nutrient agar-potato dextrose agar (BA-PDA) and their abilities to suppress Rhizoctonia damping-off were much lower than the parental strain. However, population density in the eggplant rhizosphere did not differ significantly between the parental strain and four Chi a- mutants. The crude enzyme of the parental strain inhibited growth of R. solani on NA-PDA and its chitinase activity was much higher than that of Chi a- mutants. But the N,N' -diacetylchitobiase activity between these isolates were not significantly different. The chitinase of Chi a- mutants was defective in 2 isoforms of 52- and 37-kDa among four isoforms of 54-, 52-, 50- and 37-kDa. A Tn5 element was inserted into one site of 10 kb EcoRI fragment of chromosomal DNA in three Chi- mutants, C61-C1, -C2, and -C3. In C61-C4 mutant, a Tn5 element was inserted into two sites of 10 kb and 4.4 kb EcoRI fragments. These results suggest that the chitinase of C. violaceum C-61 play an important role in the suppression of Rhizoctonia damping-off of cucumber and eggplant.

• Applied Biological Chemistry
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• v.14 no.3
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• pp.229-235
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• 1971

Kwanok, Fujisaka #5, Paldal, and Suwon #82 as japonica type and IR-262 and CP-slo as indica type of rice seeds were selected for this experiment among varieties grown in Korea. Activities of crude enzymes extracted from germinating seeds of these varieties on malathion and p-nitrophenyl acetate as substrates, esterase zymograms with 1-naphthyl acetate as substrate, and some observations are summarized as follows: 1. Activities per unit volume of crude enzyme preparations on malathion were in the order of Kwanok>IR-262>Fujisaka #5>CP-slo>Paldal>Suwon #82. 2. Esterase zymograms on agar-gel electrophoretograms exhibited three to four bands two electrodes with little difference among varieties, nevertheless showing a wide and strongly-colored band toward cathode. Suwon #82 has a somewhat different pattern from others. 3. Enzyme activities per milligram protein with p-nitrophenyl acetate as substrate were in the order of CP-slo>IR-262>Paldal>Kwanok>Suwon #82>Fujisaka #5, indicating that activities of indica type are much stronger than those of japonica type, but not in agreement with results with malathion. 4. Malathion did not much inhibit the esterase activity at the concentration of 0.2PPM on electrophoretograms. 5. It is supposed that there is a complex esterase system hydrolyzing malathion and p-nitrophenyl acetate in germinating rice seeds.

• Journal of Life Science
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• v.31 no.12
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• pp.1100-1109
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• 2021

The halophyte Artemisia scoparia is an edible medicinal plant, with insecticidal, anti-inflammatory, anticholesterol, antipyretic, and antibacterial effects. The aim of this study was to assess the inhibitory effect of crude extract and solvent-partitioned fractions obtained from A. scoparia on MMP-2 and MMP-9 activity in phorbol-12-myristate-13-acetate (PMA)-stimulated human fibrosarcoma HT-1080 cells using four different activity tests: gelatin zymography, MMP enzyme-linked immunosorbent assay (ELISA), wound healing assay, reverse transcription-polymerase chain reaction (RT-PCR), and Western blot assay. A. scoparia samples were extracted twice with methylene chloride (MC) and twice with methanol (MeOH). After the MC and MeOH crude extracts were combined, the combined crude extracts showed a significant inhibitory effect against MMP-2 and MMP-9 enzymes. They were then fractionated into n-hexane, 85% (v/v) aqueous methanol (85% (v/v) aq.MeOH), n-butanol, and water according to solvent polarity. Among the four solvent-partitioned fractions, n-hexane and 85% (v/v) aq. MeOH fractions significantly inhibited MMP-2 and MMP-9 activity and cell mobility. In addition, the n-hexane and 85% (v/v) aq.MeOH fractions effectively inhibited MMP-2 and -9 activity in the gelatin zymography and MMP ELISA assay. In the wound healing assay, RT-PCR, and Western blot assay, all solvent-partitioned fractions, except the H₂O fraction, significantly suppressed cell migration, as well as the expression levels of MMP-2 and -9 mRNA and proteins.

• Korean Journal of Plant Tissue Culture
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• v.28 no.6
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• pp.297-304
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• 2001

Scrophularia buergeriana Misrule has been contaminated with various pathogens in condition of field and storage period. This study was carried out for production of multiple stress resistance plant containing disease resistance that CGST gene expressed in transgenic Scrophularia buergeriana Misrule genome. Glutathione S-Transferases (GSTs) detoxify endobiotic and xenobiotic compounds by covalent linking of tripeptide glutathione to hydrophobic substrate. GST enzymes have been identified and characterized in insects, bacteria, and many plant species. A cDNA clone of GST was introduced into Scrophularia buergeriana Miquel by transformation with Agrobacterium tumefaciences. In coporation of the CGST gene into S. buergeriana Misrule was confirmed by PCR analysis of genomic DNA. Influence of exposure to darkness on the regeneration potential and transformation frequence were assessed. The activity of GST in transgenic plants was two times higher than that of non-transgenic plants. As a result of anti-microbe assays, the crude extract protein of transgenic plants showed the antimicrobial effects higher than control plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.468-475
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• 1992

In order to understand more clearly the integration between N-assmilation and C-metabolism in relation to N fertilization, a pot experiment with 5 different level of N fertilization(0, 5, 10, 25, 50 mM NO$_3$$_{[-10]}$ ) was conducted in Manchester, U.K. The peas (Pisum sativum L., cv. Early Onward) were sown in vermiculate (5 cm depth) and cultivated for 6 days under temperature controlled dark room conditions ($25^{\circ}C$). The plants received frequent irrigation with a nutrient solution: it was fertilized every 2 days, 3 times a day at 10h, 13h, 16h respectively. Elevated NO$_3$$^{[-10]}$ concentration, the activity levels of NR, NiR, total GS(crude extract), GS$_2$(plastid) in both root and shoot were increased and reached the peak in 5～25 mM, except NiR specific activity which increased its activity continually until 50 mM NO$_3$$^{[-10]}$ treatment. Total activities of GS (crude extract) in both root and shoot became higher than those of GS$_2$(Plastid), and the activity ratios of total GS in the crude extract and GS$_2$ in the plastids were 3.0 to 4.3 in root, but 3.2 to 10.6 in shoot. It was concluded that the reductants and A TP from OPPP itself should be enough to achieve the high rate of NR, NiR, GS$_1$, GS$_2$ in plant root and shoot for reduction or assimilation of nitrogen, but these enzyme activities might be inhibited by an excess of NO$_3$$^{[-10]}$ influx over the reduction capacity.

• BMB Reports
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• v.36 no.5
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• pp.450-455
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• 2003

Antioxidant enzymes are scavenger reactive-oxygen intermediates and are involved in many cellular defense systems. We previously reported that a crude extract of Garnoderma lucidum, a medicinally potent mushroom, profoundly increased the catalase gene expression and enzyme activities in mouse livers (Park et al., J. Biochem. Mol. Biol. 34. 144-149, 2001). In this study, we elucidated the detailed mechanism whereby G. lucidum stimulates the catalase activity and expression. The major active fraction was isolated from G. lucidum and methyl linoleate was considered the most major component of the fraction. In order to determine whether methyl linoleate increases mRNA and protein synthesis of catalase, Northern and Western blot analyses were performed in vivo with methyl linoleate-treated mouse liver homogenate after feeding methyl linoleate to the mice. Northern and Western blot analyses of the crude liver homogenates in the mice that were administered methyl linoleate revealed that the expression catalase was significantly increased when compared to the untreated controls. In addition, the catalase protein levels and enzymatic activities increased in the mouse liver homogenates. These results suggest that methyl linoleate that is produced by G. lucidum stimulates the catalase expression at the transcription level.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.199-208
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• 1977

Activities of various hydrolytic enzymes produced by three plant pathogenic fungi, Sclerotium rolfsii Sacc., Sclerotinia sclerotiorum (Lieb.) deBary and Helminthosporium sigmoideum var. irregulare Crallery et Tullius, were measured. Activties and amounts of the enzymes in mycelia, cultural filtrates, and sclerotia(except of sclerotia of H. sigmoideum var. irregulare) were estimated at various pH levels in order to find out optimal pH for their enzymatic activities. Enzymes such as cellulase (ex), invertase, xylanase, $\beta-amylase$, polymethylgalacturonase, polygalacturonase, phosphatase and protease were estimated. Culture solution for production of enzymes was prepared by adding of 10g, D-glucose, 1.3g $NH_4NO_3,\; 0.5g\; MgSO_4,\;7H_2O,\; and\; 1.0g\; KH_2PO_4$ into 1 liter of potato decoction plus 2ml of micro element solution consisting of 0.2mg. Fe, 0.2mg Zn, and 0.1mg Mn as the sulphates into 1 liter of distilled water. All tested mycelia and cultural filtrates were obtained from the cultures incubarted in previous solution for ten days at $25^{\circ}C$, and sclerotia were harvested from PDA plates of 3. days old, The crude enzyme solutions were prepared according to the method of Miyazaki etal. Ten days after incubation, activities of Cx produced by Scl. sclerotiorum were higher than those of the other fung and each of Cx from three fungi showed different pH optima, such as S. rolfsii and Scl. schlerotiorum in acid side (around pH 3.0), H. sigmoideum var. irregulare in neutral side (around pH 6.3). Invertase activities of S. rolfsii were 20 times higher than those of the other fungi in all samples. All tested fungi, however, showed no significant difference between the enzymatic activities of their cultural filtrate and mycelia and the activities in sclerotia of S. rolfsii and Scl. sclerotiorum were hardly recognized. There were multiple peaks on the xylanase activity curves of three fungi in terms of pH values. High activities of the xylanase were revealed in sclerotia of S. rolfsii and Scl. sclerotiorum, and in mycelia of H. sigmoideum var. irregulare. The highest activities of $\beta-amylase$ were shown both in mycelia and cultural filtrate of H. sigmoideum var. irregulae among the tested fungi, and their optimal pH was 6.2 in both mycelia and cultural filtrate. In the S. rofsii and Sel. sclerotiorum, however, the activities of cultural filtrates were higher than those of the other fungi, and optimal pH was 3.0 and 6.2 for cultural filtrate and both mycelia and sclerotia, respectively. Activities of PMG were high in cultural filtrates of all tested fungi, especially in Scl. sclerotiorum and H. sigmoideum var. irregulare. Mycelia of themalso showed the considerable activities. Optimal pH for enzymatic activities were variable with thekind of fungi or with the samples measured. The highest activities of PG were presented by mycelia of S. rolfsii and Scl. sclerotiorum. $9.l\mu /min.\; and\; 9.5\mu g/min.$, respectively. Optimal pH for activity of PG in mycelia was around 4.5 in S. rolfsii and around 3.0 in Scl. sclerotiorum. Phosphatase of S. rolfsii and Scl. sclerotiorum was more active in acid side (optimal PH3. 5) and that of H. sigmoideum var. irregulare showed one peak each in acid, neutral and alkaline side. But the highest peak was at pH 9.5. Protease of all tested fungi was more active at pH 10.0, especially that of the cultural filtrate of H. sigmoideum var. irregualre.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1150-1157
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• 2011

Streptomyces sampsonii KK1024 having strong chitinolytic activity was isolated from crab-shell rich soil at Muan, Jeolanamdo. The KK1024 produced chitinase, protease, gelatinase and lipase. When 50% of KK1024 culture broth was treated to juveniles and eggs of root-knot nematode, juvenile mortality at 3 days was 81.67% and egg hatch rate at 5 days was 2.00%. When $183.7{\mu}g\;mL^{-1}$ of crude enzyme produced by KK1024 was treated, juvenile mortality at 3 days was 96.00% and egg hatch rate at 5 days was 5.33%. At 1% of butanol extract from KK1024, juvenile mortality was highest with 90.00% and egg hatch rate was lowest with 0%. The comparison of the effect of KK1024 culture broth with only medium, synthetic fertilizer, and commercial nematicide on tomato growth and nematode infection was examined in pot trials. KK1024 culture broth showed lower number of egg mass and gall in plant, and population of juveniles in soil compared with only medium and synthetic fertilizer treatment, but not in commercial nematicide. However, the highest shoot weight and length was discovered in KK1024 culture broth. These results suggest that Streptomyces sampsonii KK1024 producing lytic enzymes and nematicidal compounds can be one of candidates for biocontrol agents against root-knot nematodes.