• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.311-314
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• 1985

Ganodema lucidum protoplasts were formed by the treatment of Novozym 234. The osmotic stabilizers such as mannitol were effective enough to produce protoplasts up to 10$^{6}$ $m\ell$. For regeneration, however, MgSO$_4$.7$H_2O$ was suitable. When inositol and sucrose were employed as osmotic stablizers, the regeneration ratio reached to 0.26％. Overlay of Streptomycin sulfate added agar was required to prevent bacterial contamination.

• The Korean Journal of Mycology
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• v.23 no.4 s.75
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• pp.305-309
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• 1995

To investigate optimal conditions for the protoplast formation and regeneration of Phanerochaete chrysosporium, preparations of three enzymes were used to liberate protoplasts from its 20 hrs-old mycelium on cellophan membrane covered agar media. Novozym 234 alone with 0.6M sucrose was the most effective for isolation of protoplasts from the mycelium with 3hrs incubation time at $39^{\circ}C$ in shaking condition of 120 rpm. The poly-R medium stabilized with 0.6M mannitol was the best for regeneration of the protoplasts.

• Korean Journal of Pharmacognosy
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• v.24 no.3
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• pp.197-202
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• 1993

Three components, fraxetin-8-glucoside, esculetin-6-glucoside and mannitol, were isolated from the stem bark of Fraxinus chiisanensis var. stenophylla, F. japonica var. intermedia and F. densata. The MeOH extract of the cortex of F. densata had the antiinflammatory activity on the carrageenin-induced paw edema in rat. The MeOH extracts of the cortex of all three Fraxinus spp. have the potent analgesic activity on the HOAc-induced writhing syndrome in mouse and the hepatoprotective activity on the $CCl_4-induced$ fatty liver in rat: protection of ballooning formation and inhibition of sGPT and sGOT increased by $CCl_4$.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.415-418
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• 2000

Productivity of a rice plant is greatly influenced by salt stress. One of the ways to achieve tolerance to salinity is to transfer genes encoding protective enzymes from other organisms, such as microorganisms. The bacterial gene, mtlD, which encodes mannitol-1-phosphate dehydrogenase (Mtl-DH), was introduced to the cytosol of a rice plant by an imbibition technique to overproduce mannitol. The germination and survival rate of the imbibed rice seeds were markedly increased by transferring the mtlD gene when it was delivered in either a pBIN19 or pBmin binary vector. When a polymerase chain reaction was performed with the genomic DNAs of the imbibed rice leaves as a template and with mtlD-specific primers, several lines were shown to contain an exogenous mtlD DNA. However, a reverse transcription (RT)-PCR analysis revealed that not all of them showed an expression of this foreign gene. This paper demonstrates that the growth and germination of rice plants transiently transformed with the bacterial gene, mtlD, are enhanced and these enhancements may have resulted from the experssion of the mtlD gene. The imbibition method empolyed in this study fulfills the requirements for testing the function of such a putative gene in vivo prior to the production of a stable transgenic plant.

• 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.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.49-57
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• 1994

The objective of this study was to determine whether Pz-peptide, an enhancer of hydrophilic solute permeability in the intestine, could elevate the paracellular permeability of the cornea and conjunctiva in the pigmented rabbit. The in vitro penetration of four hydrophilic solutes, mannitol (MW 182), fluorescein (MW 376), FD-4 (FITC-dextran, 4 KDa), and FD-10 (FITC-dextran, 10 KDa) across the pigmented rabbit cornea and conjunctiva was studied either in the presence or absence of 3 mM enhancers. Drug penetration was evaluated using the modified Ussing chamber. The conjunctiva was more permeable than the cornea to all four markers. EDTA and cytochalasin B showed higher effects on marker transport than Pz-peptide, but Pz-peptide elevated the corneal transport of mannitol, fluoresein, and FD-4 by 50%, 26%, and 50%, respectively, without affecting FD-10 transport. Possibly due to the leakier nature of the conjunctiva, 3 mM Pz-peptide elevated the transport of only FD-4 by about 45%, without affecting the transport of other markers. Furthermore, the transport of Pz-peptide itself across the cornea and conjunctiva increased with increasing concentration in the 1-5 mM range, suggesting that Pz-peptide enhanced its own permeability, possibly by elevating paracellular permeability. Effects of ion transport inhibitors on Pz-peptide transport were then investigated. PZ-peptide penetration was not changed by mucosal addition of $10\;{\mu}M$ amiloride or $10\;{\mu}M$ hexamethylene amiloride, inhibiting serosal $Na^{+}$ exit by $100\;{\mu}M$ ouabain, or replacing $Na^{+}$ with choline chloride in the mucosal side buffer. These results seggested that Pz-peptide enhanced the paracellular permeability of rabbit cornea and conjunctiva and further indicate that ion transporters were not involved in the Pz-peptide induced elevation of paracellular marker permeability.

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.315-321
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• 1980

A steady-state kinetic study on a dye-coupled cytoplasmic polyol dehydrogenase from G. melanogenus was carried by the initial velocity measurements in the direction of the polyol oxidation and the product inhibition by D-fructose. For the initial rate experiments, D-mannitol and D-sorbitol were employed as the specific polyol substrates and 2,6-dichlorophenolin-dophenol (DPIP) as the specific cofactor substrate for the enzyme. When the polyol and DPIP were examined by varying one of substrates and by fixing the second, the corresponding reciprocal plots showed the typical parallel pattern. This suggests that the enzyme from G. melanogenus proceeds by a Ping Pong Bi-Bi mechanism in which the polyol may account as the first reactant-in, and the ketose formed as the first product-out, respectively. The product inhibition patterns obtained by D-fructose (one no-inhibition, one non-competitive, and two competitive) may also provide an additional conformatory evidence for the above mechanism. Based on the kinetic parameters obtained, it was also suggested that the rate-limiting step in the direction of polyol oxidation is associated with the release of the ketose from the Enzyme${\cdot}$Polyol complex.

• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.153-157
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• 2001

Protoplasts were isolated from hypocotyls, cotyledons, and young leaves of Chinese cabbage grown under in vitro environmental condition. An enzyme mixture of 1% Cellulysin and 0.5% Macerozyme in combination with 0.4 M mannitol was most effective condition for protoplast isolation. The highest yield of protoplasts, 7.6$\times$10$^{5}$ protoplast/g of fresh weight, was obtained from the treatment of leaves for 12~16 hours at 27~28$^{\circ}C$ with shaking at 30 rpm. The most suitable medium for an initial cell division was K8p basal medium supplemented with 5 mg/L 2,4-D and 2 mg/L kinetin. Within 7~10 days, protoplasts derived from hypocotyl and cotyledon tissues formed cell colonies. When the cells were grown at the size of 8~10 cells, they were embedded into semi-solid medium containing 0.2% agarose. Calli derived from protoplast culture were transferred to the 100 different types of plant regeneration media, but no completely regenerated plants from inbred lines of Chinese cabbage used for this study wore obtained, though frequent rooting took place in several media tested.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.208-214
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• 2009

To avoid ambiguity in counting the number of colony, about 1,500 of colonies grown on B. cereus selective agar plates were grouped into 12 types by morphological difference and then identified by biochemical and 16S rDNA nucleotide sequence. Among them, seven colony types with 11 to 15 mm diameters of halo were identified as B. cereus or B. cereus subsp. cytotoxis. Five mm sized colonies with no halo, which have not been considered as B. cereus according to the manufacturer's manual, were identified as B. cereus. A colony type with double halos of only 6 mm in diameter was also B. cereus. Other three types were proven to be Enterococcus sp., Brevibacillus sp., and B. subtilis, respectively. PCR results showed that only 9 types that are identified as B. cereus strains harbor at least one of B. cereus toxin genes.

• Environmental Analysis Health and Toxicology
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• v.25 no.4
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• pp.295-306
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• 2010

Objectives : This study was undertaken to examine the metabolomic changes due to gender and diurnal variation at sampling time and to identify an appropriate time point for urine sampling in epidemiologic studies using metabolomic profiles. Methods : Urine samples were collected twice a day (morning and afternoon) from 20 healthy Korean adults after fasting for 8 hours. The metabolomic assay was investigated using $^1H$ NMR spectroscopy coupled with the principal components analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The metabolites responsible for differentiation between groups were identified through the loading plot of PLS-DA and quantified using Chenomx NMR Suite with a 600 MHz library. Results : Metabolites responsible for differentiation in gender and sampling time were creatinine, trimethyl anine oxide (TMAO), hippurate, mannitol, citrate and acetoacetate. Dimethylamine showed difference only as a factor of diurnal time. The level of creatinine was higher in men compared to women, and the levels of citrate, TMAO, hippurate, mannitol, and acetoacetate were higher in women compared to men. The levels of creatinine, TMAO, hippurate, dimethylamine and mannitol were higher in the morning rather than the afternoon while those of citrate and acetoacetate were higher in the afternoon rather than the morning. Conclusions : Since urinary metabolomic profiles varied by gender and diurnal cycle, urine sampling should be performed at the same time point for all participants in epidemiologic studies using metabolomic profiles.