• Microbiology and Biotechnology Letters
• /
• v.4 no.4
• /
• pp.138-144
• /
• 1976

five strains of Streptomyces spp. with high Productivity of glucose isomerase (15-30 units/ml) were obtained among 280 microbial strains isolated from 150 soil samples. These strains produced glucose isomerase with xylose as an inducer. These 5 strains were also identified to be different strains of Streptomyces spp.：streptomyces sp. K-14, K-53, K-71, K-77 and K-733. It was found that Streptomyces sp. K-14 produced the highest enzyme activity. The spore chains of these strains were rectiflexible and spore surface was smooth except Steptomyces sp. K-77 and K-733, with spiny surface.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.563-566
• /
• 2000

In order to obtain microbial endochitosanase for enzymatic production of chitooligosaccharides from chitosan, we screened four microbes from soil and selected. Bacillus sp. HSB-21 which showed highest activity. Chitosanase, produced from isolating microbe, was endo-type and molecular mass of the enzyme was estimated as 21,000 by active staining. Its optimum pH and temperature were 5.5 and $50^{\circ}C$, respectively. It was stable in the pH range of 3.0 to 8.0 and up to $40^{\circ}C$. It did not produce chitomonosaccharide and produced chitooligosaccharide ranging from chitobiose to chitooctaose as major end-products from chitosan. The chitosanase from Bacillus sp. HSB-21 can be applicable to enzymatic production of chitooligosaccharide which has high degree of polymerization .

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.4
• /
• pp.328-334
• /
• 2002

A Lindernia dubia (L.) Pennell var. dubia accession from Jeonnam province, Korea was tested for resistance to sulfonylurea (SU) herbicides, imazosulfuron and pyrazosulfuron-ethyl in whole-plant response bioassay. The accession was confirmed resistant to both herbicides. The $GR_{50}$ (herbicide concentration that reduced shoot dry weight by 50%) values of resistant accession were 264 and 19 times higher to imazosulfuron and pyrazosulfuronethyl, respectively, than that of the standard susceptible accession. The surviving resistant L. dubia after pyrazosulfuron-ethyl + molinate application can be controlled by sequential applications of soil-applied herbicides, butachlor, dithiopyr, pyrazolate, and thiobencarb and foliar herbicides, bentazon. Sulfonylurea-based mixtures such as mixtures of azimsulfuron + anilofos, bensulfuron-methyl + oxadiazon, pyrazosulfuron-ethyl + fentrazamide, and pyrazosulfuron-ethyl + anilofos + carfentrazon can also be used to control the surviving resistant L. dubia. However, use of these mixtures should be restricted to a special need basis. Thus, we suggest that sequential applications of non-SU-based mixtures such as butachlor + pyrazolate and MCPB + molinate + simetryne be used to control the surviving resistant L. dubia after SU herbicide applications. Rice yield was reduced 24 % by resistant L. dubia that survived after the pyrazosulfuron-ethyl + molinate application compared with pyrazolate + butachlor in transplanted rice culture. In vitro ALS activity of the resistant biotype was 40 and 30 times more resistant to imazosulfuron and pyrazosulfuron-ethyl, respectively, than the susceptible biotype. Result of in vitro ALS assay that the resistance mechanism of L. dubia to SU herbicides may be due, in part, to an alteration in the target enzyme, ALS.

• Microbiology and Biotechnology Letters
• /
• v.22 no.6
• /
• pp.665-671
• /
• 1994

For the production of pyrogallot from gallic acid, about 100 strains of bacteria capable of assimilating gallic acid as a sole carbon and energy source were isolated from the soil. JH- 004 strain showing the highest activity of gallate decarboxy#lase was selected from them and identi- fied as Erwinia sp. The optimal conditions for the production of pyrogallol from gallic acid were examined. The resting cells of JH-004 cultured in a complex medium containing 0.2%(w/v) gallic acid were prepared after the treatment of the pellet with a freezing and thawing, and used as a enzyme source. The reaction mixtures for the maximal production of pyrogallol were shown to be 6 g/l of resting cells and 15 g/l of gallic acid in 25 mM potassium phosphate buffer. The optimal pH for the reaction was 5.0 and the optimal temperature was 35$\circ$C . Additionally, Triton X-100(0.01%, w/v) was found to be most effective for the production of pyrogallol. Under the above conditions, 10.27 g/l of pyrogallol was produced from 15 g/l of gallic acid after incubation of 35 hrs. This amount of pyrogallol corresponds to a 92.37% yields, based on gallic acid.

• Korean Journal of Microbiology
• /
• v.40 no.3
• /
• pp.211-216
• /
• 2004

A bacterial strain JE-ll found to produce active extracellular phospholipase D (PLD) was selected from the soil isolates. It was identified as Streptomyces somaliensis on the basis of 16S rDNA sequence analysis, morphological and physiological characteristics. The gene (sspld) encoding S. somaliensis PLD was isolated and characterized. The open reading frame was suggested to encode 538 amino acids with a signal peptide of 33 amino acids. The deduced amino acid sequence of the sspld shared a sequence similarity of 70-88％ with PLDs of other Streptomyces sp. so far reported. The PLD converted phosphatidylcholine to phosphatidylglycerol or phosphatidylserine with the yield of 96 to 99％ (㏖/㏖), but did not act on inositol or ethanolamine as a transphosphatidylation donor.

• Microbiology and Biotechnology Letters
• /
• v.19 no.3
• /
• pp.296-302
• /
• 1991

Glucose isomerase producer, which produces 488 U/ml of glucose isomerase activity in 500 ml flask scale, was isolated among 666 isolates of Actinomycetes from pine forest soil samples. The isolate was identified as Streptomyces luteogriseus through the studies about morphology (spiral aerial mycelia), cell wall type (Type I), spore chains (spiral form), pigment formation (gray melanine pigment) & metabolism (sugar utilization etc). The optimum conditions of fermentation were determined in 500 ml flask scale. The enzyme production was reached maximum after 4 days at pH 6.0~8.0 and 27~$30^{\circ}C$ in the medium containing 1.5~3.0% of xylose; 0.5-0.8% of glucose; 0.1% of $MgSO_4.7H_20$; 0.05% of $CoCI_2-6H_20$; 7.5% of corn steep liquor.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.35 no.1
• /
• pp.109-114
• /
• 2006

For the purpose of oligosaccharide production from alginate, the main component in cell walls of brown algae, the alginate degrading bacteria have been screened from the seaweeds and soil. Among the isolated 69 strains, one strain showing the highest degrading activity was selected and identified as Bacillus licheniformis strain. The adequate sodium alginate concentration for growing the Bacillus licheniformis was $2.0\%$. The effective nitrogen source is nutrient broth $(0.1\%)$, and optimum initial pH, NaCl concentration, temperature and incubation time to produce the alginate degrading enzyme were 7.5, $2\%,\;30{\pm}2^{\circ}C$, and 144 hrs, respectively.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.10
• /
• pp.1520-1524
• /
• 2005

Young radishes (YR, yeolmu in Korean) were cultivated in the soil with and without sulfur. Young radish kimchi-general (YR kimchi-G) was prepared with YR commonly cultivated in the soil without sulfur. Young radish kimchl-sulfur (YR kimchi-S) and young radish kimchi-sulfur with lime mortar (YR kimchi-SL) were prepared with the YR cultivated in the soil with sulfur an4 sulfur added lime mortar on it respectively. Antitumor effects of methanol extracts from the YR kimchis were investigated in sarcoma-180 tumor cell transplanted mice. The solid tumor growth was significantly inhibited by the YR kimchi-SL prepared with YR grown in the soil with sulfur (p < 0.05). The treatment of the methanol extracts from YR kimchi-S and -SL increased the glutathione S-transferase activities and glutathione contents in the livers, compared to thlose of YR kimchi-G and the control. One of the antitumor effects by the YR kimchis was due to the increased the glutathione levels and the glutathione S-transferase activity which is phase 2 enzyme. These results also suggested that the antitumor effects of YR kimchi can be enhanced by using YR cultivated differently in the presence of sulfur that can help to produce sulfur-containing compounds in YR.

• Korean Journal of Soil Science and Fertilizer
• /
• v.39 no.1
• /
• pp.15-20
• /
• 2006

Biological control by chitinolytic microorganisms is being evaluated as management options for soilborne diseases. Forty kilograms of chitin compost (CTC) and control compost (CC) were amended on tomato plots ($15m{\times}0.5m$) 7 d before transplanting to evaluate enzymatic activities and the control of Fusarium wilt. Samples were taken on day 1, 3, 5, and 7, the day 1 corresponded to the 66 d after transplanting, the day on which the initial wilting symptoms occurred in plants of CC treated plots. The chitinase activity in soil of CTC was always higher compared to the control. Pathogenesis related (PR) protein (chitinase, ${\beta}$-1, 3-glucanase and peroxidase) activities in tomato roots in CC increased every day and showed marked differences compared to CTC. Wilting symptoms (96 d after transplanting) were reduced by 25% in CTC compared to the control. Protection of tomato plant may be correlated with the high levels of soil enzyme activities resulting from the chitin compost.

• Korean Journal of Environment and Ecology
• /
• v.24 no.4
• /
• pp.426-435
• /
• 2010

The present study attempts to compare the soil chemical characteristics and biological activities (i.e. microbial biomass and soil enzyme activities), and litter decomposition rate of Arundinella hirta and Miscanthus sinensis var. purpurascens) collected from serpentine and non-serpentine sites by litter bag techniques at serpentine and non-serpentine field experiment sites over a 9-month period. The serpentine soil showed higher pH and soil alkaliphosphatase activity, and lower soil dehydrogenase and urease activities than the non-serpentine soil. Microbial biomass-N at the serpentine soil was larger than the non-serpentine soil, although the microbial biomass-C and microbial biomass-N represented no significant difference between serpentine and non-serpentine soil. These results suggest that the larger microbial biomass-N caused the lower C/N in serpentine soil. At the end of the experiment, the litter samples of A. hirta and M. sinensis collected from serpentine soil revealed a 39.8% and 38.5% mass loss, and the litter sample from non-serpentine soil also showed a 41.1% and 41.7% mass loss at the serpentine site. On the other hand, at the non-serpentine site, 42.2%, 37.4%, and 46.8%, 44.8% were respectively shown. These results demonstrate that the litter decomposition rate is more intensely affected by the heavy metal content of leaf litter than soil contamination. Moreover, the litter collected from the serpentine soil had a lower C/N, whereas the litter decomposition rate was slower than the litter from the non-serpentine soil, because the heavy metal inhibition activities on the litter decomposition process were more conspicuous than the effect of litter qualities such as C/N ratio or lignin/N. The nutrient element content in the decomposing litter was gradually leached out, but heavy metals and Mg were accumulated in the decaying litter. This phenomenon was conspicuous at the serpentine site during the process of decomposition.