• Microbiology and Biotechnology Letters
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• v.37 no.3
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• pp.219-225
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• 2009

A bacterial strain, JE-34, producing a high concentration of red pigment was isolated from a sediment in East China Sea. It was identified as Zooshikella sp. JE-34 based on the 16S rRNA gene sequence analysis. The red pigment was purified by solvent extraction and HPLC was identified as prodigiosin-like compound. Nutritional and cultural conditions were optimized for the production of prodigiosin-like pigment in the flask level. Optimal culture conditions were at initial medium pH $6.0{\sim}7.0$, $30^{\circ}C$ and 4 days incubation. For carbon and, nitrogen sources were soluble starch and malt extract.

• KSBB Journal
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• v.11 no.1
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• pp.37-45
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• 1996

Marine bacterial strain, highly effective agar degrading, was isolated from south sea of Korea and was identified as Pseudomonas sp. This strain was named Halophilic Pseudomonas sp. W7 and accumulated an extracellular agarase which showed a high level of enzyme activity in the presence of agar and agarose. This extracellular agarase was purified by anion-exchange chromatography and gel filtration. Purified agarase showed a single protein band upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis and its molecular weight was estimated to be about 89KDa. The agarase gene was cloned into Escherichia coli JM83 using the plasmid vector pUC19. DNA fragments(3.7, 3.0Kb) of Hind III-digested chromosomal DNA of Pseudomonas sp. W7 was inserted into the Hind III site of pUC19. Selected transformants, E. coli JM83/pSWl 000000and E. coli JM83/pSW3, produced agarase and this agarase was accumulated In the cytoplasmic space.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.878-884
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• 1996

A bacterial strain, designated as Bacillu sp. IJ-3 strain, was shown to produce the extracellular soy protein coagulating enzyme and culture conditions for the production of enzyme by this microbial strain was investigated. The culture medium giving a maximum soy protein coagulating activity was consist of 20%(w/v) soymilk, 2.0%(w/v) glucose, 4.0%(w/v) yeast extract, 5.0%(w/v) polypeptone and 1.0%(w/v) potassium phosphate, monobasic. Initial pH was optimal at 6.0 and the enzyme activity in the culture usually reached a maximal level of fermentation at $35^{\circ}C.$ After the culture medium adjustment where required, enzyme activity was reached maximum at 72 hour of cultivation but this enzyme activity was reduced quickly. It can be assumed that Bacillu sp. IJ-3 strain enzyme has a specificity toward the 75 globulin.

• KSBB Journal
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• v.15 no.6
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• pp.573-577
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• 2000

The optimum fermentation conditions for the production of cellulose by a newly isolated Acetobacter sp. A9 were determined in static cultures. The strain was able to produce cellulose at $25-30^{\circ}C$ with a maximum at $30^{\circ}C$. Cellulose production occurred at pH 6.5-8.0 with a maximum at pH 6.5. The optimal culture medium was found to consists of 1.0% glucose, 1.0% yeast extract, 0.7% polypeptone, 0.15% acetic acid and 0.02% succinic acid. Cellulose production by Acetobacter sp. A9 followed the growth curve. Highest cellulose production, under optimum conditions, was $24.1m^2$, although this strain typically produced only $12.1 g/m^2$ in the basic medium. Cellulose production also depended on the depth and volume of the medium.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.193-195
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• 2016

Korean ginseng (Panax ginseng) possesses various biological and pharmacological properties. Damping-off is a critical disease on ginseng seedlings, which is caused by the fungal pathogens Rhizoctonia solani and Pythium sp.. This disease is generally controlled by the application of fungicides, but also biological control is an efficient and environmentally friendly way to prevent ginseng damping-off. In a previous study, we screened soil-borne bacteria with potential applications as biological control agents for ginseng damping-off and selected the bacterial strain Streptomyces sp. A3265, producing antifungal substances guanidylfungin and methylguanidylfungin. In this study, we investigated control efficacy of Streptomyces sp. A3265 against ginseng damping-off in the field. As a result, the incidence of damping-off was significantly reduced when soaking ginseng seeds in the culture broth of Streptomyces sp. A3265.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.836-840
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• 2011

In order to isolate thermophilic compost-promoting bacteria with high activity of cellulase and xylanase, spent mushroom substrates with sawdust were collected from mushroom cultivation farm, Jinju, Gyeongnam in Korea. Among of the isolates, one strain, designated SJ21 was selected by agar diffusion method. The strain SJ21 was identified as members of the Bacillus lincheniformis by biochemical characteristics using Bacillus ID kit and VITEK 2 system. Comparative 16S rDNA gene sequence analysis showed that strain SJ21 formed a distinct phylogenetic tree within the genus Bacillus and was most closely related to Bacillus subtilis with 16S rDNA gene sequence similarity of 99%. On the basis of its physiological properties, biochemical characteristics and phylogenetic distinctiveness, strain SJ21 was classified within the genus Bacillus, for which the name Bacillus sp. SJ21 is proposed. The cellulase and xylanase activity of Bacillus sp. SJ21 was slightly increased according to bacterial population from exponential phase to stationary phase in growth curve for Bacillus sp. SJ21.

• Journal of Microbiology and Biotechnology
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• v.31 no.3
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• pp.387-397
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• 2021

There is growing interest in the production of microalgae-based, high-value by-products as an emerging green biotechnology. However, a cultivation platform for Oocystis sp. has yet to be established. We therefore examined the effects of bacterial culture additions on the growth and production of valuable compounds of the microalgal strain Oocystis sp. KNUA044, isolated from a locally adapted region in Korea. The strain grew only in the presence of a clear supernatant of Sphingomonas sp. KNU100 culture solution and generated 28.57 mg/l/d of biomass productivity. Protein content (43.9 wt%) was approximately two-fold higher than carbohydrate content (29.4 wt%) and lipid content (13.9 wt%). Oocystis sp. KNUA044 produced the monosaccharide fucose (33 ㎍/mg and 0.94 mg/l/d), reported here for the first time. Fatty acid profiling showed high accumulation (over 60%) of polyunsaturated fatty acids (PUFAs) compared to saturated (29.4%) and monounsaturated fatty acids (9.9%) under the same culture conditions. Of these PUFAs, the algal strain produced the highest concentration of linolenic acid (C18:3 ω3; 40.2%) in the omega-3 family and generated eicosapentaenoic acid (C20:5 ω3; 6.0%), also known as EPA. Based on these results, we suggest that the application of Sphingomonas sp. KNU100 for strain-dependent cultivation of Oocystis sp. KNUA044 holds future promise as a bioprocess capable of increasing algal biomass and high-value bioactive by-products, including fucose and PUFAs such as linolenic acid and EPA.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.442-446
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• 2007

From the rhizoplane and rhizosphere of pepper, tomato, lettuce, pasture, and grass, unsoluble inorganic phosphate solubilizing bacterial strains were isolated using plate base assay on Pikovskaya's medium. Two strains, CL-1 and CL-2, which produced largest halo on plates (indicative of phosphate solubilization)were selected for further studies. Based on these biochemical and 16S rRNA analysis strains CL-1, CL-2 were found to be as species of Pseudomonas sp. and Kluyvera sp., respectively. In broth assay Pseudomonas sp. CL-1 and Kluyvera sp. CL-2 solubilized insoluble phosphate by 193.4 mg and $493.6P\;mg\;L^{-1}$, respectively after $3^{rd}$ day inoculation. These effecient phosphate solubilizing bacteria have a potential to be developed as microbial based fertilizer in future.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.95.2-96
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• 2003

In order to develop a new microbial fungicide for the control of vegetable diseases using endophytic bacteria, a total of 260 bacterial strains were isolated from fresh tissues of 5 plant species. After they were cultured in broth media, their antifungal activities were screened by in vivo bioassays against Botrytis cinerea(tomato gray mold), Pythium ultimum(cucumber damping-off), Phytopkhora infestans(tomato late blight), Colletotrichum orbiculare(cucumber anthracnose), and Blumeria graminis f. sp. hordei(barley powdery mildew). As the results of screening, 38 bacterial strains showed potent antifungal activities against at least one of 5 plant pathogens. A bacterial strain EB072 displayed potent disease control activities against 3 plant diseases. Among the bacterial strains with a potent antifungal activity against cucunlber anthracnose, three bacterial strains, EB054, EB151 and EB215, also displayed a potent in vitro antifungal activity against C. acutatum, a fungal agent causing pepper anthracnose. A bacterial strain EB215 obtained from roots of cucumber was identified as Burkholderia cepacia based on its physiological and biochemical characteristics and 165 rRNA gene sequence. An antifungal substance was isolated from the liquid cultures of B. cepacia EB215 strain by ethyl acetate partitioning, repeated silica gel column chromatography, and invitro bioassay, Its structural determination is in progress by various instrumental analyses.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1304-1312
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• 2013

The effects of storage period and aerobic deterioration on the bacterial community were examined in Italian ryegrass (IR), guinea grass (GG), and whole-crop maize (WM) silages. Direct-cut forages were stored in a laboratory silo for 3, 7, 14, 28, 56, and 120 d without any additives; live counts, content of fermentation products, and characteristics of the bacterial community were determined. 2,3-Butanediol, acetic acid, and lactic acid were the dominant fermentation products in the IR, GG, and WM silages, respectively. The acetic acid content increased as a result of prolonged ensiling, regardless of the type of silage crop, and the changes were distinctively visible from the beginning of GG ensiling. Pantoea agglomerans, Rahnella aquatilis, and Enterobacter sp. were the major bacteria in the IR silage, indicating that alcoholic fermentation may be due to the activity of enterobacteria. Staphylococcus sciuri and Bacillus pumilus were detected when IR silage was spoiled, whereas between aerobically stable and unstable silages, no differences were seen in the bacterial community at silo opening. Lactococcus lactis was a representative bacterium, although acetic acid was the major fermentation product in the GG silage. Lactobacillus plantarum, Lactobacillus brevis, and Morganella morganii were suggested to be associated with the increase in acetic acid due to prolonged storage. Enterobacter cloacae appeared when the GG silage was spoiled. In the WM silage, no distinctive changes due to prolonged ensiling were seen in the bacterial community. Throughout the ensiling, Weissella paramesenteroides, Weissella confusa, and Klebsiella pneumoniae were present in addition to L. plantarum, L. brevis, and L. lactis. Upon deterioration, Acetobacter pasteurianus, Klebsiella variicola, Enterobacter hormaechei, and Bacillus gibsonii were detected. These results demonstrate the diverse bacterial community that evolves during ensiling and aerobic spoilage of IR, GG, and WM silages.