• Korean Journal of Microbiology
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• v.23 no.2
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• pp.90-100
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• 1985

The present study was designed to investigate cellular regulation of phosphate metabolism between catabolically repressed and derepressed states in yeast (Saccharomyces uvarum). The activities of various phospatases and the contents of phosphate compounds were detected according to the culture phase and various phosphate concentrations. As the results, Saccharomyces uvarum derepressed many phosphate metabolizing enzymes such as alkaline phosphatase, acid phosphatase and ATPase more than ten fold simultaneously during catabolic repression (phospgate and sugar starvation). At the same state, the amounts of orthophosphate, nucleotidic labile phosphate and acid soluble polypgosphate were increased, compared to basal levels of normally cultivated cells. $Mg^{++}-stimulated$ type among all phospatases was appeared to have most of the enzyme activity. It could be postulated that $K^+ -stimulated$ alkaline phosphatase was directly or indirectly correlated with the synthesis of acid insoluble polyphosphate $Mg^{++}-stimulated$ phosphatase with the degradation of polyphosphates. In case of cultivation in the medium supplemented with sugar and phosphate (catabolic derepression), phospgatase activities except for alkaline phosphatase were decreased rapidly through the progressive batch culture, After 12 hrs culture, at early exponential phase, the cellular accumulation of acid insoluble polyphosphate increased about 5 fold, compared to those of the starved cells. Under catabolic repression, it could be postulated that intracellular phosphate metabolism was regulated by derepressions of phosphatases. The function of polyphosphate system was shown to compensate the ATP/ADP system as phosphate donor and energy source especially during catabolic repression.

• Korean journal of food and cookery science
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• v.23 no.3 s.99
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• pp.314-320
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• 2007

The objective of this study was to investigate the effect of grain size on the physicochemical properties of rice porridge. Here, the grain size of the rice was classified as whole grain, half grain, and flour by traditional Korean cooking methods. The viscosity of the rice flour porridge was highest for the among the three different grain size porridges. In the amylographs, the increase in viscosity for the whole grain porridge was higher than that of the rice flour porridge during cooling. The soluble solid and reducing sugar contents of the rice porridges increased according to the rice grain size, while the blue value decreased. The SDI (starch digestion index) increased according to the rice grain size. The RDS (rapidly digestible starch) was highest while the SDS (slowly digestible starch) the lowest in the rice flour porridge. The morphologies of the rice porridges were examined by SEM and showed a smoother surface and more exudated gelatinized granules in the rice flour than in the whole grain rice porridge. In conclusion, rice porridges made from the smallest possible grain size such as flour may be helpful for people with weaker digestive systems such as infants, the elderly, and hospital patients.

• Herbal Formula Science
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• v.24 no.4
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• pp.301-309
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• 2016

Objective : The main objective of the study is to measure the satisfaction of patients with the Bojungikgi-tang Soft Extract, which is a herbal medicine in a new dosage form. Methods : Data were collected from 23 patients at Dongshin University Sunchun Korean Medicine Hospital through survey questionnaires. Results : A total of 23 patients were included in the study to know their satisfaction level towards the Bojungikgi-tang Soft Extract. It was found that most of the respondents were satisfied with the Bojungikgi-tang Soft Extract regarding its effectiveness, taste, convenience, price, and transportability in comparison to existing dosage forms. Conclusion : The study showed that most patients were more satisfied with the new drug dosage form than traditional forms and in needs of diversify of herbal medicine dosage forms.

• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1184-1192
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• 2011

A bacterial isolate (strain JS-2) characterized as Bacillus sp. was challenged with high concentrations of toxic selenite ions. The microbe was found to transform the toxic, soluble, colorless selenite (${SeO_3}^{2-}$) oxyions to nontoxic, insoluble, red elemental selenium ($Se^0$). This process of biotransformation was accompanied by cytoplasmic and surface accumulation of electron dense selenium ($Se^0$) granules, as revealed in electron micrographs. The cells grown in the presence of selenite oxyions secreted large quantities of extracellular polymeric substances (EPS). There were quantitative and qualitative differences in the cell wall fatty acids of the culture grown in the presence of selenite ions. The relative percentage of total saturated fatty acid and cyclic fatty acid increased significantly, whereas the amount of total unsaturated fatty acids decreased when the cells were exposed to selenite stress. All these physiological adaptive responses evidently indicate a potentially important role of cell wall fatty acids and extracellular polymeric substances in determining bacterial adaptation towards selenite-induced toxicity, which thereby explains the remarkable competitiveness and ability of this microbe to survive the environmental stress.

• Membrane and Water Treatment
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• v.15 no.1
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• pp.1-9
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• 2024

Biological nutrient removal is gaining increasing attention in wastewater treatment plants; however, it is adversely affected by low temperatures. This study examined temperature effects on nutrient removal and morphological stability of the granular and denitrifying phosphorus accumulating organisms (PAO and DPAO, respectively) using sequencing batch reactors (SBRs) at 5, 10, and 20 ℃. Lab-scale SBRs were continuously operated using anaerobic-anoxic and anaerobic-oxic cycles to develop the PAO and DPAO granules for 230 d. Sludge granulation in the two SBRs was observed after approximately 200 d. The average removal efficiency of soluble chemical oxygen demand (SCOD) and PO₄^3--P remained >90% throughout, even when the temperature dropped to 5 ℃. The average removal efficiency of NO₃^--N remained >80% consistently in DPAO SBR. However, nitrification drastically decreased at 10 ℃. Hence, the removal efficiency of NH₄⁺-N was decreased from 99.1% to 54.5% in PAO SBR. Owing to the increased oxygen penetration depth at low temperatures, the influence on nitrification rates was limited. The granule in DPAO and PAO SBR was observed to be unstable and disintegrated at 10 ℃. In conclusion, morphological characteristics showed that changed conversion rates at low temperatures in aerobic granular sludge altered both nutrient removal efficiencies and granule formation.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.42-47
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• 2016

The purpose of this study was to evaluate the quality characteristics in different types of Omija (Schizandra chinensis Baillon) powder tea. Raw Omija was prepared in three ways: 1) freeze-dried powder of whole Omija (FD), 2) freeze-dried powder of pressed Omija juice (PF), and 3) granules of pressed Omija juice (PG). Dried Omija was extracted and prepared in three ways: 4) freeze-dried powder (EF), 5) granules (EG), and 6) spray-dried powder (ES). The total soluble solid contents and turbidity were higher in PG, EG, and ES than those in other samples. $L^*$ value, pH, and reducing sugar contents were higher in PG and EG than those in other samples. Finally, $a^*$ value, $b^*$ value, total phenolic compounds contents, antioxidant activities, total anthocyanin contents, and schizandrin contents were lower in PG and EG than those in other samples. These results show that FD, PF, EF, and ES are more effective in outstanding redness and antioxidant activities compared to other Omija powder products.

• Applied Biological Chemistry
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• v.41 no.7
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• pp.516-521
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• 1998

Solubility patterns and gelatinization properties of two waxy rice starches, Sinsunchalbyeo and Hwasunchalbyeo, were investigated. Shapes of all starch granules were round and polygonal, and their X-ray diffraction patterns were all A type. Amylose content and water binding capacity of Sinsunchalbyeo were similar to those of Hwasunchalbyeo. The swelling powers and solubilities of two starches were increased with increasing temperature in range of $65{\sim}95^{\circ}C$, and those of Hwasunchalbyeo was higher. Iodine affinities of soluble fractions in Sinsunchalbyeo starch were higher than those in Hwasunchalbyeo at the same temperature and both were increased with increasing temperature. λmax of soluble fraction of Sinsunchalbyeo starch was highest at $75^{\circ}C$ of heating temperature. The transmittance of starch suspensions were increased rapidly at $60{\sim}65^{\circ}C$. By Rapid Visco Analyzer, initial gelatinization temperature of Sinsunchalbyeo was $67.2^{\circ}C$, and that of Hwasunchalbyeo was $68.2^{\circ}C$. In DSC analysis, onset temperature for gelatinization of Sinsunchalbyeo and Hwasunchalbyeo were $61.3^{\circ}C\;and\;62.9^{\circ}C$, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.55-59
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• 1984

An organic compound fertilizer was manufactured using wet oxidation human waste as principal source of phosphorus and organic matter. The waste was treated with sulfuric and glutamic acids to increase the available and water-soluble $P_2O_5$ contents. The treatment of 0.1 N sulfuric acid with 24 hours curing was best way in recovering the maximum percentage of $P_2O_5$ originally in the waste. The particle size distribution of trial product varied considerably in the amount of glutamic acid used for granulation. The number of relatively large fertilizer particles was increased as the amount of glutamic acid was increased. The granule crushing strength was generally high in large granules in which 12.5 weight percent of glutamic acid were used for granulation. The trial product showed high moisture absorption due to its porous structure and chemical makeup.

• Journal of Powder Materials
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• v.9 no.6
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• pp.441-448
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• 2002

Dispersions of non-soluble ceramic particles in a metallic matrix can enhance the strength and heat resistance of materials. With the advent of mechanical alloying it became possible to put the theoretical concept into practice by incorporating very fine particles in a flirty uniform distribution into often oxidation- and corrosion- resistant metal matrices. e.g. superalloys. The present paper will give an overview about the mechanical alloying technique as a dry, high energy ball milling process for producing composite metal powders with a fine controlled microstructure. The common way is milling of a mixture of metallic and nonmetallic powders (e.g. oxides. carbides, nitrides, borides) in a high energy ball mill. The heavy mechanical deformation during milling causes also fracture of the ceramic particles to be distributed homogeneously by further milling. The mechanisms of the process are described. To obtain a homogeneous distribution of nano-sized dispersoids in a more ductile matrix (e.g. aluminium-or copper based alloys) a reaction milling is suitable. Dispersoid can be formed in a solid state reaction by introducing materials that react with the matrix either during milling or during a subsequent heat treatment. The pre-conditions for obtaining high quality materials, which require a homogeneous distribution of small dis-persoids, are: milling behaviour of the ductile phase (Al, Cu) will be improved by the additives (e.g. graphite), homogeneous introduction of the additives into the granules is possible and the additive reacts with the matrix or an alloying element to form hard particles that are inert with respect to the matrix also at elevated temperatures. The mechanism of the in-situ formation of dispersoids is described using copper-based alloys as an example. A comparison between the in-situ formation of dispersoids (TiC) in the copper matrix and the milling of Cu-TiC mixtures is given with respect to the microstructure and properties, obtained.

• Korean Journal of Animal Reproduction
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• v.17 no.3
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• pp.183-191
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• 1993

These experiments were carried out to investigate whether the enzyme is involved in zona hardening during normal activatin of the oocytes by sperm, and demonstrate peroxidase activity during in vitro fertilization of oocytes treated with peroxidase inhibitors(250 $\mu$M phenylhydrazine, 28mM sodium sulfite, 350mM glycine ethyl ester and 50mM sodium azide) and tyrosine analogue(12.5mM tyramine). Also, zona soluble properties of the ovarian oocytes incubated for 0, 5, 10 and 15 hr in the presence of pheylhydrazine or tyramine were studied by using $\alpha$-chymotrypsin. The results obtained from these experiments were summarized as follows ; 1. The rates of fertilizatin in control oocytes and oocytes treated with phenylhydrazine or tyramine were 69.8%, 62.3% and 88.2%, respectively. However in vitro fertilization in oocytes treated with three different peroxidase inhibitors, sodium sulfite, glycine ethyl ester and sodium azide, were not induced. The oocytes treated with phenylhydrazine had no significant effect on in vitro fertilization rate as compared to control. However there was a significantly different in fertilization between tyramine treated group and control group(P<0.01). 2. The zona solubility(t50) of control and fertilized oocytes in culture treated with phenylhydrazine or tyramine were 30.7, 26.0 and 16.3 min., respectively. Phenylhydrazine treated group and tyramine treated group had effect on inhibition of zona hardening as compared to control group. These results suggest that ovoperoxidase is involved in zona hardening during normal activation of the oocytes by sperm. 3. t50 of control oocytes and ovarian oocytes treated with phenylhydrazine or tyramine for 5, 10 and 15 hr in vitro were 14.0, 26.2 and 32.0 min., 14.5, 26.9 and 30.2 min., and 14.0, 24.3 and 31.2 min., respectively. These results suggest that zona hardening in ovarian oocytes matured for various times in vitro cannot be inhibited by peroxidase inhibitors and tyrosine analogue, that the spontaneous zona hardening incultured ovarian oocytes is not caused by the secretory products of cortical granules released during the cortical reaction, ovoperoxidase.