• Korean Journal of Microbiology
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• v.46 no.4
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• pp.346-351
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• 2010

The purpose of this work was to investigate the characteristics of a biosurfactant-producing bacterium isolated from crude-oil contaminated soils. During the incubation of strain HK-3 with 1% crude-oil, bacterial growth pattern, the amount of biosurfactant production, and pH changes were monitored. In order to examine the effect of supplemented carbons on the production of biosurfactant, cultivation of HK-3 cells in BH media with different carbons (e.g. glucose, dextrose, mannitol, citrate, or acetate) revealed that the production of biosurfactant reached the maximal level at the 72 h incubation with mannitol, which the area of clear zone was measured to approximately 7.64 $cm^2$. Identification test using the BIOLOG system, morphology study based on scanning electron microscopy and the 16S rRNA sequence-based phylogenetic analysis assigned strain HK-3 to a Pseudoalteromonas species, designated as Pseudoalteromonas sp. HK-3 which was registered in GenBank as [FJ477041].

• The Plant Pathology Journal
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• v.27 no.4
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• pp.390-395
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• 2011

Fusarium wilt caused by Fusarium oxysporum has become a serious problem world-wide and relies heavily on chemical fungicides. We selected Pseudomonas sp. NJ134 to develop an effective biocontrol strategy. This strain shows strong antagonistic activity against F. oxysporum. Biochemical analyses of ethyl-acetate extracts of NJ134 culture filtrates showed that 2,4-diacetylphloroglucinol (DAPG) was the major compound inhibiting in vitro growth of F. oxysporum. DAPG production was greatly enhanced in the NJ134 strain by adding mannitol to the growth media, and in vitro antagonistic activity against F. oxysporum increased. Bioformulations developed from growth of NJ134 in sterile bean media with mannitol as the carbon source under plastic bags resulted in effective biocontrol efficacy against Fusarium wilt. The efficacy of the bioformulated product depended on the carbon source and dose. Mannitol amendment in the bean-based formulation showed strong effective biocontrol against tomato Fusarium wilt through increased DAPG levels and a higher cell density compared to that in a glucose-amended formulation. These results suggest that this bioformulated product could be a new effective biocontrol system to control Fusarium wilt in the field.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.529-534
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• 2016

Bioethanol was produced using the separate hydrolysis and fermentation (SHF) method with macroalgal polysaccharides from the seaweed, Undaria pinnatifida as biomass. This study focused on the pretreatment, enzymatic saccharification, and fermentation of yeasts in co-culture. Ethanol fermentation with 14.5% (w/v) seaweed hydrolysate was performed using the yeasts, Saccharomyces cerevisiae KCTC 1126 alone, Pichia angophorae KCTC 17574 alone, and their co-cultures with the yeasts either adapted to mannitol or not. Among the combinations, the co-culture of non-adapted S. cerevisiae and P. angophorae adapted to mannitol showed high bioethanol production of 12.2 g/l and an ethanol yield ($Y_{EtOH}$) of 0.41. Co-culture in the SSF process was employed in this study, to increase the ethanol yields of 35.2% and reduction of 33.3% in fermentation time. These results provide suitable information on ethanol fermentation with marine seaweeds for bioenergy production.

• Korean Journal of Clinical Laboratory Science
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• v.37 no.1
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• pp.27-34
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• 2005

Biochemical characteristics, enterotoxin production and antimicrobial susceptibility were determined for 30 strains of Bacillus cereus isolated from stool specimens of diarrhea patients at an university hospital in Chulabuk-do province. Positive rate for VP reaction and citrate utilization were lower, (33 % and 40 % respectively) while the rates of acid production from mannitol, arabinose, and xylose were higher (17 %, 13 % and 3 % respectively) than those obtained by other investigators. The enterotoxin gene was detected in 18 of 30 isolates (60 %) by PCR, and the toxin was detected from all of the toxin gene-positive isolates by RPLA test. The agar dilution test showed that all isolates were resistant to penicillin G and 73 % were to cephalothin, but all were susceptible to ciprofloxacin, clindamycin, erythromycin, fusidic acid, gentamicin, rifampin, teracycline and vancomycin. We conclude that B. cereus isolates producing acid from mannitol, arabinose and xylose exist, that PCR can be used to detect enterotoxin genes rapidly and accurately, and that this organism is susceptible to various antimicrobial agents though not penicillin G and cephalothin.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.617-620
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• 2004

The present study compares development of rabbit embryos generated using different oocyte activation protocols and reconstructed with embryonic or cumulus cells as nuclear donor. In vivo matured oocytes were collected from New Zealand White rabbits at 16 h after ovulation treatment and were activated at18 h of post-ovulation treatment. The following schemes of oocytes activation were tested: 1) single electric pulse (EP, 3.2 kV/cm, 3${\times}$20 $\mu$s, 0.3 M mannitol)+5 min culture in the presence of 5 mM Ionomycin, 2) single electric pulse (EP, 3.2 kV/cm, (${\times}$20 $\mu$s, 0.3 M mannitol)+1 h culture in the presence of 2 mM 6-DMAP, and 3) three electric pulses 30 min apart. Cleavage rate, percentage of expanded and hatched blastocysts as well as total cell number of blastomeres of parthenogenetic embryos were significantly higher using either EP+6-DMAP or 3${\times}$EP schemes, comparing with EP+Ionomycin. Development rate up to hatched blastocyst stage of cloned rabbit embryos using the EP+6-DMAP for activation of nuclei were 19% for embryonic cell nuclei and 36% for cumulus cell nuclei. The best activation protocol optimalized in this study was the combined treatment "P+6-DMAP" which may be potentially used for nuclear transfer protocol.

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.207-212
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• 1989

Cultural conditions for $\alpha$-D-Glucosidase Inhibitor production from Streptomyces sp. YS-221-B isolated from soil arid identified as Streptomyces flauovirens or a subspecies of it were investigated. When the strain was cultured in a flask containing 2% glucose, 0.3% asparagine, 0.0002% riboflavin, 0.05% $K_2$HPO$_4$, 0.1% MgSO$_4$.7$H_2O$, 0.05% NaCl, pH 8.0 at 3$0^{\circ}C$, maximum production of the inhibitor was obtained after 8-9 days of cultivation. Sugar alcohols such as mannitol, i-inositol, erythritol as carbon sources, asparagine and beef extract as nitrogen sources were favorable for inhibitor production. Among vitamins, riboflavin, p-aminobenzoic acid, pyridoxamine and folic acid promoted the production of inhibitor, but depressed by the addition of hesperidine, and also depressed by cobalt, lithium and ferrous salts.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.219-226
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• 2015

Acetic acid bacteria (AAB) were isolated from vinegar fermented through traditional methods in Namhae county, Gyeongnam, the Republic of Korea. The isolated strains were Gram negative, non-motile, and short-rods. Three selected strains were identified as either Acetobacter pasteurianus or Acetobacter aceti by 16S rRNA gene sequencing. A. pasteurianus NH2 and A. pasteurianus NH6 utilized ethanol, glycerol, D-fructose, D-glucose, D-mannitol, D-sorbitol, L-glutamic acid and Na-acetate. A. aceti NH12 utilized ethanol, n-propanol, glycerol, D-mannitol and Na-acetate. These strains grew best at 30℃ and an initial pH of 3.4. They were tolerant against acetic acid at up to 3% of initial concentration (v/v). The optimum conditions for acetic acid production were 30℃ and pH 3.4, with an initial ethanol concentration of 5%, resulting in an acetic acid concentration of 7.3−7.7%.

• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.132-138
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• 1996

This experiment was carried out to establish a year-round production system of pathogen-free stock through micropropagation in Fritillaria thunbergii as medicinal bulbous plant. The effect of different types of culture method and plant growth regulators, activated charcoal and mannitol on bulblet formation and subsequent growth were investigated. The MS solid medium containing 1. 0 mg/L kinetin and 0. 3 mg/L NAA was effective on bulblet formation and propagation rate compared to liquid and suspension culture. Addition of activated charcoal at 0. 01% to 0. 1% in the medium promoted bulbing of cultured bulblets and shoot formation. Addition of 1% to 2% mainnitol in MS medium was effective on the formation of bulblet and subsequent growth of bulblets compared to control. In addition of inhibitors, $10{\sim}100\;mg/L$ B-9 and Chloromequat had effective to stimulate bulblet growth but their effects were not so much as mannitol treatment. ABA treatment had detrimental effect on survival rate of explant and bulblet formation.

• The Korean Journal of Mycology
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• v.23 no.1 s.72
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• pp.53-60
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• 1995

Nutritional requirements for the growth of Flammulina velutipes were studied. Mannitol, glutamic acid and ammonium nitrate were chosen for the maximum mycelial growth when various carbon and nitrogen sources tested. Optimum C : N ratio for the mycelial growth was 20 : 1. Potassium dihydrogen phosphate was selected among the phosphate sources. Magnesium sulphate and thiamine HCl stimulate mycelial growth. Final compositions of optimized chemically defined medium were 1.5% mannitol, 0.082% $NH_4NO_3$, 0.312% glutamic acid, 0.25% $KH_2PO_4$, 0.06% $MgSO_4{\cdot}7H_2O\;and\;0.3\;{\mu}g/l$ thiamin HCl. This medium not only support mycelial growth but also induce fruit body formation.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.331.1-331.1
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• 2002

Actinomycetes CS0703 has been isolated in soil sample from location in the Jeju province. Korea. and produces alkaline extracellular proteases. To maximize protease production, initial pH of the culture medium was adjusted to 12.0 with NaOH and incubated at $48^{\circ}C$ on a rotary shaking incubator(180rpm). Actinomycetes CS0703 produced high level of protease at late exponential phase when grown in OSYM medium (oatmeal 2.0%. soybean meal 1%. dried yeast 1%. mannitol 1%). (omitted)