• The Journal of Korean Academy of Prosthodontics
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• v.44 no.1
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• pp.124-134
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• 2006

Statement of problem: Streptococcus produces energy and forms extracellular polysaccharides by metabolizing sucrose. Insoluble glucan, a kind of extracellular polysaccharide, is the important material of dental plaque. Fructose affects the metabolism of sucrose. Purpose: The purpose of this study was to evaluate the effect of fructose on the metabolism of sucrose in Streptococcus mutans. Materials and methods: To determine the effect of fructose on the formation of artificial plaque by Streptococcus mutans Ingbritt, S. mutans and fructose were placed in beakers containing M17 broth and sucrose. The wires were hung on frameworks inserted into cork stoppers, and then immersed in each of the beakers. After the incubation with gentle shaking, each wire was weighed. To analyze the effect of fructose on the sucrose metabolism by S. mutans or glucosyltransferase, S. mutans and fructose were placed in M17 broth containing sucrose. After the incubation. the remaining sucrose and polymers were analysed by thin layer chromatography. Results: The following results were obtained; 1. When Streptococcus mutans was cultured in the media containing 3% sucrose for 8 hours, the mean weight of formed artificial plaque on the wires was $124.3{\pm}3.0mg$, whereas being reduced to $20.7{\pm}10.2mg$ in the media added with 3% sucrose and 4% fructose(p<0.05) 2. When the control containing glucose was added with sucrose, the optical density of Streptococcus mutans solution cultured for 24 hours was not increased compared with the control, while being increased by adding with fructose. 3. When Streptococcus mutans was incubated in the media added with sucrose and fructose for 8 hours, the number of viable cells was increased compared with the media added with sucrose. 4. The amount of remained sucrose was increased in Streptococcus mutans culture supernatant of media added with sucrose and fructose than with sucrose only. but the amount of produced insoluble glucan was decreased. 5. The amounts of remained sucrose and produced soluble glucan were increased in the culture of glucosyltransferase-contained media added with sucrose and fructose than with sucrose only, but the amount of produced insoluble glucan was decreased . Conclusion: These results indicated that the sucrose metabolism and the production of insoluble glucan were inhibited in Streptococcus mutans by adding fructose in the media containing sucrose.

• Korean Journal of Plant Tissue Culture
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• v.21 no.2
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• pp.117-121
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• 1994

The optimal level of growth regulator for callus initiation stem explants was BAP 0.1mg/L combined with 2,4-D 1.0 mg/L in Murashige and Skoog (MS) medium supplemented with 30g/L sucrose and 10g/L agar, and that for cell growth was BAP 0.1+2,4-D 0.5 mg/L in MS liquid medium. The regeneration frequency of P. oleracea cells was significantly increased by subjecting the cells to dessication for 1and 2 h up to 83%, respectively, as compared with untreated control showing 61%. Cell viability and survival rate was inhibited by pretreatment of 0.6% NaCl for 2 days, while regeneration ability was not affected by the treatment. Pretreatment of 100g/L sucrose for 2 days markedly stimulated the regeneration of cells up to 81%. These results suggest that in addition to physiological changes, water stress resulted from dessication and high concentration of sucrose and NaCl is closely related to the regeneration of P. oleracea cultured cells.

• Korean Journal of Health Education and Promotion
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• v.7 no.2
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• pp.71-77
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• 1990

Streptococcus mutans 10449 was cultured in sucrose-containing BHI broth with ethyl alcohol of different concentration from 1% to 18%, The pH of culture media was from pH 7.00 to pH 5.00. Tobacco smoke and tobacco extract were also used. Ethyl acohol began to inhibit sucrose fermentation by S. mutans at 2% and completely inhibited it between 9% and 18%. The lower the pH of media was, the stronger the inhibition of ethyl alcohol became. 9% Ethyl alcohol completely inhibited sucrose fermentation by S. mutans below pH 5.50, Inhibition by tobacco extract was obvious, but it did not inhibit the growth of S. mutans also. Therefore, the increase of caries activity in drinkers and smokers could be the result of indirect effect of alcohol and tobacco by oral ecology, behavior, or systematic course, rather than the result of direct effect of alcohol and tobacco to plaque bacteria and their metabolism.

• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.69-74
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• 2000

The medium for erythritol production by Torula sp. in a 500-ml baffled flask was optimized to be 300 g/I sucrose, 10 g/I yeast extract, 3 g/I $KH_2PO_4$, and 10 mg/I $CuSO_4{\cdot}5H_2O{\;}at{\;}34^{\circ}C$ with initial pH of 5.5. Using this optimal medium, erythritol of 166 g/I was obtained after 140 h of cultivation, corresponding to 55.3% of the erythritol yield from sucrose with a productivity of 1.11 g/I/h. Optimal concentrations of carbbon and nitrogen sources in a fermentor were higher than that in a flask due to the higher oxygen supply of the fermentor. Employing the medium containing 300 g/I or 400 g/I sucrose for the determination of optimal C/N ratio, the C/N ratio was found to be more important than the nitrogen concentration for effective erythritol production, The optimal ratio of yeast extract to sucrose (g/g) was 20. The yield and productivity of erythritol were maximal in the medium containing 400 g/I sucrose and 20 g/I yeast extract. when dissolved oxygen in the culture was increased, the cell mass increased but the erythritol production was manimal in the range of 5 to 10% of dissolved oxygen. Under the optimal the rane of 5 to 10% of dissolved oxygen. Under the optimal culture condition of the fermentor, a final erythritol concentration of 200 gI was obtained after 120 h with a yield of 50% and the productivity was 1.67 g/I/h. The yield was the highest among erythritol-producting microorganisms

• Journal of Plant Biotechnology
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• v.6 no.4
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• pp.241-246
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• 2004

The bulb scales and shoot sections ($7\;\cal{mm}\;\times\;15\;\cal{mm}$) of Lilium oriental hybrid 'Casablanca' were cultured to compare bulblet growth in vitro. Shoots were induced from in vitro grown bulbscales on MS medium with $1.0\;\cal{mg/L}\;BA,\;0.5\;\cal{mg/L}$ IAA, and 30 g/L sucrose. The regenerated shoots were cut into shoot sections, and cultured on MS medium with $2.0\;\cal{mg/L}\;BA,\;0.5\;\cal{mg/L}$ IAA and 30 g/L sucrose for shoot proliferation. Culture of shoot sections stimulated bulblet growth significantly than the bulb scales on MS medium with 60 g/L sucrose. However, the bulblets from shoot sections did not reach ideal size to produce stems with several leaves. Therefore, liquid medium was added into the same vessels to stimulate bulblet growth further. After shoot sections were cultured on MS medium with 60 g/L sucrose and 2 g/L activated charcoal for two months in dark, $20\;\cal{ml}$ liquid media containing various concentrations of sucrose and MS salts were added. Two months later, the added liquid medium stimulated bulblet growth remarkably as compared to bulblets grown without added liquid medium. The added $25\;\cal{ml}$ liquid medium containing 120 g/L sucrose and double strength of MS salts were the most effective for growth of in vitro bulblets. More than $94\%$ bulblets produced by this method sprouted stems with several leaves after cold treatment at $5^{\circ}C$ for three months.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.121-126
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• 2006

Saikosaponin productivity was examined in a Bupleurum falcatum L. BFHR2 hairy root culture in response to changes in the sucrose content $(2{\sim}8%)$, nitrogen content $(0{\sim}250mM\;NH_4NO_3)$, phosphate content $(0{\sim}12mM\;NaH_2PO_4)$, and the potassium content $(0{\sim}87.2 mM\; KCl)$ of the culture media. We found that the conditions for maximal saikosaponin production differed from those for optimal root growth. Highest saikosaponin yield was achieved for 8% sucrose, 62mM $NH_4NO_3$ 1.2 mM $NaH_2PO_4$, and 0.5mM KCl.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.74.2-74
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• 2003

Arabidopsis infected with beet curly top virus (BCTV) has the systemic symptoms like stunting of Plant growth, curling of leaves and shoot tips, and callus induction. The regulation of sucrose metabolism by BCTV infection is essential for obtaining the energy source in the process of virus replication and symptom development. Sucrose metabolism-associated gene expression and biochemical enzyme activity were analyzed with the rossette leaves and inflorescencestems of BCTV infected Arabidopsis by the time course of 1, 7, 14, 21 day postinoculation. The expression of invertase and sucrose synthase genes ( encoding sucrose-cleaving enzymes )was increased and reversely the level of Atkin10a ( sucrose non-fermenting gene ) was decreased, resulting by semi-quantitative reverse transcription polymerase chain reaction. The biochemical analysis of invertase and sucrose synthase activity was performed. The activity of neutral invertase in the inflorescence stems was elevated remarkably. The photosynthetic response in the source of sucrose metabolism was consistent with the down-regulation of ribulose 1,5 bisphosphate carboxylase gene, and lower activity than mock-inoculated plants. The levels of genes pertaining to the cell cycle, hormone, and biotic stress-related pathway showed an increase or a decrease dependent on viral symptoms. Therefore, sucrose sensing by BCTV infection can regulate the expression of sucrose metabolism-related key enzymes such as invertase and Atkin10a, and these gene products might influence to symptom development.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.454-460
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• 2009

Phyllanthus urinaria was an important species in Korea and distributed in all around of Korea. The roots and stems of this plant have been used for natural medicine for the treatment of diabetes, the hepatitis B virus and disturbances of the kidney and urinary bladder. Production of adventitious roots in P. urinaria by in vitro cultures could be used as alternatives materials. Shoot and root segments from P. urinaria seedling were cultured on Murashige and Skoog (MS) medium supplemented with 3.0 mg/L IBA and 30 g/L sucrose. After 4 weeks of culture, the highest induction of adventitious roots was obtained from the shoot part. Frequency of adventitious root formation on medium with various kinds of auxins (IAA, NAA, 2,4-D, and IBA) and various concentrations of IBA (0, 0.1, 0.5, 1.0, 3.0, and 5.0 mg/L) was tested. The maximun induction of adventitious root was obtained on medium with 0.5 mg/L IBA. In liquid culture, growth of root was best on medium supplemented with 30 g/L sucrose. Adventitious roots were cultured in 5 L bioreactor containing 1/2 MS medium supplemented with 0.5 mg/L IBA and 30 g/L sucrose and mass-production of adventitious roots was successfully achieved. These results revealed the first attempt for the production of adventitious roots in P. urinaria.

• BMB Reports
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• v.28 no.2
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• pp.184-190
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• 1995

Functional study of the gap junction channel has been hindered by its inaccessibility in situ. Identification of forms of this channel in artificial membrane has been elusive because of the lack of identifying channel physiology. Connexin32 forms gap junction channels between neighboring cells in rat liver. Connexin32 was affinity-purified using a monoclonal antibody and reconstituted into artificial phospholipid vesicles. The reconstituted connexin32 formed channels through the vesicle membrane that were permeable to sucrose (Stokes radius: $5{\AA}$). The permeability to sucrose was reversibly reduced by acidic pH. In addition, the pH effect on the permeability to sucrose fit well with by the Hill's equation (where, n=2.7 and pK=6.7).

• The Journal of the Korean dental association
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• v.19 no.2 s.141
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• pp.163-166
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• 1981

Sugar consumption has been increased in recent days according to an improvement in living conditions. It is generally accepted that sugar is one of the causes of caries and that diabetes mellitus is closely related to the periodontal diseases. This investigation was designed to gain informations on the influence of overdosage of sugar and/or high blood sugar level on the periodontal tissue. 12 rats weighing about 1.5Kg were divided into 4 groups, control one and 3-day, 7-day, 14-day ones after daily administration of 30-50 gm of sucrose. The results were as follows: 1. Daily adminisration of 30-50 gm of sucrose elevated blood glucose level as much as 10-20 mg% than before. 2. Epithelial keratinization was gradually conspicuous to the dosage of sucrose. 3. The severity of inflammatory infiltration was also increased to the dosage of sucrose. 4. Inflammatory infiltration was encountered in marginal gingiva more than other periodontal tissue.