• KSBB Journal
• /
• v.15 no.1
• /
• pp.27-34
• /
• 2000

A marine bacterium having a high oil-degrading activity was isolated form the oil-polluted southern sea of Korea, and was identified as Pseudomonas aeruginosa and was named Pseudomonas aeruginosa BYK-2. The optimal tmeperatur, culture time, pH and NaCl concentration for biosurfactant production and cell growth showed $25^{\circ}C$, 48h, 7.0 and 0%(w/v), respectively. After cultivation at $25^{\circ}C$, 180 rpm in 250 mL erlenmeyer flask for 7days, 1%(w/v) arabian light crude oil and bunker C oil which are considered to be hardly degradable compounds were degraded 92.1%(w/w) and 76%(w/w) respectively. And then, cell adherence was measured on various carbon sources. The cell adherence indicated over 80% on hydrocarbons(arabian light crude oil, kuwait curde oil, bunker C oil, n-paraffine, n-hexadecane, n-tetradecane) as carbon sources. Lecithin among fatty acids(oleic acid, olive oil, lecithin) showed highest cell adherence of 91.5%. The cell adherence of sugars(arabinose, trehalose, dextrose, galactose, lactose, fructose, maltose, sorbitol, sucrose) observed to be less than 70% except for arabinose, galactose, sorbitol and sucrose.

• Journal of Food Hygiene and Safety
• /
• v.37 no.5
• /
• pp.332-338
• /
• 2022

Cereal grains are the dietary staple in many countries, including the Republic of Korea. These grains are usually consumed cooked. Korean grown raw and cooked brown non-glutinous rice (BNR), white non-glutinous rice (WNR), oats, and barley were analyzed to assess the effects of cooking on dietary fiber and free sugar content. The largest decrease in total dietary fiber (TDF) after cooking was observed in barley (11.62±1.26 to 2.96± 0.90 g/100 g), and the smallest decrease was observed in oats (8.1±0.34 to 8.1±0.32 g/100 g). Soluble dietary fiber decreased in oats (3.35±0.94 to 1.25±0.03 g/100 g) while insoluble dietary fiber increased (4.76±0.78 to 6.90±0.30 g/100 g) after cooking. TDF content was not changed. Of the six free sugars routinely assessed, only sucrose was detected in BNR and WNR. Sucrose decreased by about 0.6 g/100 g in BNR, and was not detected in WNR, after cooking. Fructose, sucrose, and raffinose were detected in oats (0.08, 0.83, and 0.19 g/100 g) and barley (0.09, 0.58, and 0.22 g/100 g) Maltose was also detected in barley (0.09 g/100 g). Total sugar content decreased in every cereal grain sample after cooking. This research reveals that dietary fiber and free sugar content can be reduced by cooking cereal grains.

• Journal of Plant Biology
• /
• v.36 no.3
• /
• pp.211-218
• /
• 1993

Plant regeneration was accomplished from protoplast culture of rice (Oryza sativa L. cv. Taebaeg). Embryogenic callus was induced from mature seed on MS medium containing 5 mM proline, 2.5 mg/L 2,4-D, 30 g/L sucrose in the dark at 28$^{\circ}C$ and used to establish embryogenic cell suspension culture. Suspension cells were subcultured every one week in N6 medium supplemented with 5 mM proline, 200 mg/L casein hydrolysate, 2.5 mg/L 2,4-D and amino acids of AA medium. Suspension cultures were composed of cells that were densely cytoplasmic, potentially embryogenic and were at least maintained for more than 6 months in liquid medium. Protoplasts were isolated from fast-growing suspension culture cells and cultured in a slightly modified KpR medium by mixed nurse culture. Isolated protoplasts began to divide within 5~7 days and thereafter, protoplast-derived calli were sequentially transferred to callus proliferating medium that soft agar MS medium contained 2 mg/L 2,4-D and produced distinct embryogenic cells. Microcolonies were then transferred to solid medium which consisted of MS medium containing 5 mg/L kinetin, 1 mg/L NAA, 1 mg/L ABA, 30 g/L sucrose and 10 g/L sorbitol under fluorescent light. Mulitple shoots of 4~5 per callus emerged and were transferred to hormone-free MS medium for root initiation. Thereafter, The plantlets were transferred to pots of soil to mature in the culture room.

• Applied Biological Chemistry
• /
• v.40 no.1
• /
• pp.34-38
• /
• 1997

For the effective production of functional oligosaccharides(DP 3-5) from inulin in chicory extracts, the acid hydrolysis and enzymatic endo-inulinase reaction were compared. Acid hydrolysis was unfavorable ; the content of oligosacharides in total sugar increased to 26.0% for 12 min at $55^{\circ}C$ and 24.6% at 6 min at $65^{\circ}C$ and showed little change for 30 min. The content of high DP(DP 6) decreased from 83.5 to 49.5% and 23.0% for 30 min, repectively. Glucose, fructose and sucrose increased to 24.6% and 50.3%, respectively. Hydrolysis of chicory extracts with purified endo-inulinase from Arthrobacter sp. S37 was carried out at $40^{\circ}C$ and pH 7.5 for 44 hrs. The content of high DP($DP{\geq}6$) in total sugar decreased from 83.5 to 23.0% and that of inulobiose(F2) and DP 3-5 increased to 66.1%. Glucose, fructose and sucrose were not produced. The hydrolysis of chicory extracts without DP 1 and DP 2 with crude or with purified enzyme were also carried out. In contrast to the hydrolysate of crude enzyme, that of purified endo-inulinase did not contain glucose, fructose, sucrose, F2 and 1-kestose(GF2). The content of oligosaccharides in the hydrolysate of the purified endo-inulinase were 79.2%, composed mainly of inulotriose(F3), inulotetraose(F4) and inulopentaose(F5), which shows that the enzymatic hydrolysis using purified endo-inulinase from Arthrobacter sp. S37 is the best method for oligosaccharides production from inulin in chicory extracts.

• Applied Chemistry for Engineering
• /
• v.2 no.1
• /
• pp.64-69
• /
• 1991

A lipid containing a 1, 2-dithiolane group was synthesized, and polymerized vesicle was prepared from the vesicle of this lipid by ring-opening polymerization. Reaction rate of the polymerization was monitored by UV absorption, and the results showed that it followed the first order kinetics and the rate constant $3.84{\times}10^{-2}min^{-1}$. Permeation rate of sucrose through the polymerized vesicle was $4.7{\times}10^{-8}cm\;hr^{-1}$, which is 1.5 times lower than that of monomeric analog.

• Journal of Plant Biotechnology
• /
• v.44 no.3
• /
• pp.325-329
• /
• 2017

A micropropagation method via callus for Ranunculus kazusensis Makino, an endangered species, was established. When stem segments were cultured on MS media supplemented with 1.0 mg/L IAA, NAA, IBA and 2,4-D, the highest frequency of callus induction was achieved on MS medium supplemented with 1.0 mg/L NAA. Multiple shoot per explant was obtained, the MS medium containing 1.0 mg/L BA and 0.5 mg/L NAA. Additionally, effect of activated charcoal (AC) and sucrose on shoot growth in in vitro culture were examined. The most suitable conditions for shoot growth after 4 weeks of culture were the MS medium with AC and sucrose. This in vitro propagation protocol will be valuable for conservation and mass propagation of this endangered plant.

• Korean Journal of Plant Resources
• /
• v.12 no.2
• /
• pp.107-119
• /
• 1999

In this study, the induction regeneration of callus from immature embryo in trifoliata orange (Poncirus trifoliata RAFIN.) were accomplished. The embryogenic calli were induced from the immature embryo derived from seed when the calli were irradiated for 16hr at about 2,000 Lux in $\frac{1}{2}$ MS medium supplemented with 3% sucrose, and 44.4$\mu$M BA. Regeneration to whole plants was the most successful in MS medium containing 5.0$\mu$M BA. The yellowish callus was developed at 2 to 3 weeks of culture and the callus was changed from yellow to green at 5 to 6 weeks culture. In vitro regeneration was directly induced from embryogenic callus in MS medium containing 3% sucrose and 5.0$\mu$M BA. Multishoot was formed at 16 weeks culture. Moreover, when the root-formed plantlet was transplanted to soil, they grew to a whole plant. The compact cultured-cells were observed by light microscope after 4 weeks of cultivation and the embryogenic clumps were formed about the 5 weeks. At the same time, the neighboring cells were liquefied. In addition, differentiation of leaf and stem from the callus was observed after 12 weeks. The developed oil sacs and the profacicular cambium of the immature leaf were observed after 18 weeks. Therefore, we can see the considerable changes of cell arrangements according to the developmental stages of calli from trifoliata orange.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.11
• /
• pp.1606-1610
• /
• 2002

The dynamics of fermentation were studied with Italian ryegrass ensiled in the laboratory silos. The silos were kept in the room set at 25$^{\circ}C$, and then were opened on 0.5, 1, 2, 3, 5, 7 and 14 days after ensiling, respectively. The samples were taken from three silos at each sampling time for chemical analyses. Mono-and disaccharides composition was determined for glucose, fructose and sucrose by high performance liquid chromatography. The Italian ryegrass silage succeeded to achieve lactate type fermentation; high values of lactic acid (85.83 g/kg) and lactic acid/acetic acid at the end of ensiling (14 day), low values of pH (3.74), acetic acid (5.38 g/kg), ethanol (19.20 g/kg) and $NH_3-N/Total\;N$ (75.84 g/kg), no or only small amounts of butyric acid, valeric acid and propionic acid. The fermentation dynamics showed a fast and large pH decrease caused by a fast and large production of lactic acid during the first 5 days. Mono-and disaccharides composition largely decreased within initial 0.5 day (12 h) of ensiling. Sucrose disappeared rapidly within initial 0.5 day of ensiling, and fructose and glucose contents showed an initial rise during ensiling, and then decreased gradually. These indicated that the enzymes of plant tissue were active within 2 days of ensiling, which caused the initial rise in fructose and glucose from the hydrolysis of sucrose and fructans. After 5 days of ensilage, glucose was consumed completely, suggesting that glucose was the first fermentation substrate. After 2 days of ensiling, sum amounts of lactic acid and remaining mono-and disaccharides proved to be larger than the quantity of mono-and disaccharides in the initial grass. From the facts mentioned above, it was suggested that considerable amounts of lactic acid were produced from some other substrate such as fructans than initial mono-and disaccharides.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.9
• /
• pp.1321-1327
• /
• 2011

The microorganism producing an invertase (E.C. 3.2.1.26) was isolated from wine and tentatively identified as Saccharomyces cerevisiae by cellular fatty acid analysis. The invertase was purified to homogeneity by ammonium sulfate precipitant, dialysis, ion-exchange chromatography on DEAE-Sephadex A-50, and gel chromatography on Sephadex G-200 from the culture supernatant of Saccharomyces cerevisiae JS59. The specific activity and the purification fold of the purified invertase were 7620.9 unit/mg protein and 13.9, respectively. The molecular weight of the purified invertase was estimated to be 38.5 kDa by SDS-PAGE. The optimum pH and temperature for the invertase activity were pH 5 and $55^{\circ}C$, respectively. The invertase activity was relatively stable at pH 4~6 and temperature $55^{\circ}C$. The activity of invertase was inhibited by $Ag^{2+}$ and $Hg^{2+}$, but on the contrary, activated by $Co^{2+}$ and $Mn^{2+}$. Michaelis constant ($K_m$) for invertase reaction in sucrose solution was 11.5 mM. TLC analysis of the products produced in sucrose solution during invertase reaction showed the progressive presence of glucose and fructose in accordance with sucrose hydrolysis.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.2
• /
• pp.210-216
• /
• 2008

Leuconostoc mesenteroides SM isolated from a raw carrot was used for the fermentation of carrot juice (CJ). Lactic acid fermentation of CJ was performed at $25^{\circ}C$ for 24 hr with $0{\sim}20%$ sucrose concentration, resulting in the production of mucilage. The fermented CJ showed the complete conversion of sugar into dextran after fermentation for 24 hr in the presence of sucrose below 15% concentration. With 15% sucrose, the fermented CJ had pH 3.8, 0.9% acidity, consistency index of $3.5\;Pa{\cdot}s^n$. After cold storage for 3 weeks, fermented CJ showed slight increase in acidity and relatively constant value in pH; however, the consistency index, red color value and viable cell counts were slightly decreased for 3 weeks. The ${\beta}-carotene$ content in CJ was drastically decreased by lactic acid fermentation for 24 hr, indicating $72\;{\mu}g/mL$ as compared to $142\;{\mu}g/mL$. The fermented CJ had improved body texture, red color and stability without sedimentation.