• Journal of Microbiology and Biotechnology
• /
• 제21권2호
• /
• pp.204-211
• /
• 2011

To yield high concentrations of protein expressed by genetically modified Escherichia coli, it is important that the bacterial strains are cultivated to high cell density in industrial bioprocesses. Since the expressed target protein is mostly accumulated inside the E. coli cells, the cellular product formation can be directly correlated to the bacterial biomass concentration. The typical way to determine this concentration is to sample offline. Such manual sampling, however, wastes time and is not efficient for acquiring direct feedback to control a fedbatch fermentation. An E. coli K12-derived strain was cultivated to high cell density in a pressurized stirred bioreactor on a pilot scale, by detecting biomass concentration online using a capacitance probe. This E. coli strain was grown in pure minimal medium using two carbon sources (glucose and glycerol). By applying exponential feeding profiles corresponding to a constant specific growth rate, the E. coli culture grew under carbon-limited conditions to minimize overflow metabolites. A high linearity was found between capacitance and biomass concentration, whereby up to 85 g/L dry cell weight was measured. To validate the viability of the culture, the oxygen transfer rate (OTR) was determined online, yielding maximum values of 0.69 mol/l/h and 0.98mol/l/h by using glucose and glycerol as carbon sources, respectively. Consequently, online monitoring of biomass using a capacitance probe provides direct and fast information about the viable E. coli biomass generated under aerobic fermentation conditions at elevated headspace pressures.

• 대한지역사회영양학회지
• /
• 제4권3호
• /
• pp.412-420
• /
• 1999

The amount and type of dietary protein that effects affect bone mineral loss after menopause and different dietary patterns may influence anthropometric measurements, biochemical values, and bone metabolism. Objective : Our objective was to investigate bone metabolism and chronic disease factors in two different dietary patterns. Design: The sample consisted of 40 lacto-ove-vegetarians(LOV) and 49 omnivores aged from 47 to 85 years in good condition without any medical problems. Results : The average energy intake of LOV was 1414.0kcal and omnivores, 1403.2kcal. The difference between means was not statistically significant. The differences of means of body weight and BMI between the two groups were not significant but the systolic blood pressure of LOV group was significantly lower than omniovores(p<0.05). The values of serum cholesterol(p<0.05) and glucose(p<0.05) of LOV were signifcantly lower than that of omnivores. The serum albumin level(p<0.01) of LOV was lower than it'scounterpart but in a normal range. The intake of crude fiber(p<0.05) of LOV group was significantly higher. The urinary pH of LOV was 7.4 and that of omnivores was 6.3(p<0.001). Plant calcium(p>0.05) and plant iron(p<0.001) had positive correlations with the uninary pH but animal protein(p>0.05) and animal iron(p>0.05) had negative correlations with the urinary pH. The level of urinary biochemical marker of bone resorption, deoxypyridinoline(DPD) of LOV was significantly lower than the other group(p>0.05). The T-scores of bone mineral density for the two sites in the two groups were not significantly different. Conclusions : The DPD level and urinary pH value of LOV were more desirable for the bone metabolism that the omnivores. The diet of LOV had lower risk factors of chronic diseases than the other group.

• Journal of Microbiology and Biotechnology
• /
• 제17권6호
• /
• pp.1010-1017
• /
• 2007

Two alternative pathways for methionine biosynthesis are known in Corynebacterium glutamicum: one involving transsulfuration (mediated by metB and metC) and the other involving direct sulfhydrylation (mediated by metY). In this study, MetB (cystathionine ${\gamma}-synthase$) and MetY (O-acetylhomoserine sulfhydrylase) from C. glutamicum were purified to homogeneity and the biochemical parameters were compared to assess the functional and evolutionary importance of each pathway. The molecular masses of the native MetB and MetY proteins were measured to be approximately 170 and 280 kDa, respectively, showing that MetB was a homotetramer of 40-kDa subunits and MetY was a homohexamer of 45-kDa subunits. The $K_m$ values for the O-acetylhomoserine catalysis effected by MetB and MetY were 3.9 and 6.4 mM, and the maximum catalysis rates were $7.4\;(k_{cat}=21\;S^{-1})\;and\;6.0\;(k_{cat}=28\;S^{-1})\;{\mu}mol\;mg^{-1}\;min^{-1}$, respectively. This suggests that both MetB and MetY can be comparably active in vivo. Nevertheless, the $K_m$ value for sulfide ions by MetY was 8.6mM, which was too high, considering the physiological condition. Moreover, MetB was active at a broad range of temperatures $(30\;and\;65^{\circ}C)$ and pH (6.5 and 10.0), as compared with MetY, which was active in a range from 30 to $45^{\circ}C$ and at pH values from 7.0 to 8.5. In addition, MetY was inhibited by methionine, but MetB was not. These biochemical data may provide insight on the role of the parallel pathways of methionine biosynthesis in C. glutamicum with regard to cell physiology and evolution.

• Asian-Australasian Journal of Animal Sciences
• /
• 제16권12호
• /
• pp.1725-1731
• /
• 2003

Effect of strategically supplemented pregnancy allowance was ascertained during different phases of gestation on the reproductive performance of does. Gravid does (18) were allotted to 3 dietary treatments HH, HL and LH in a completely randomized block design. All does were provided wheat straw ad libitum and supplemented with concentrate mixture at the rate of $20g/kgW^{0.75}$ from 0-60 days post-mating. Subsequently, HH group was given concentrate at the rate of $40g/kgW^{0.75}$ from 61 d post-mating to term. HL group was offered concentrate from 61-90 d post-mating and 121d post mating to term at the rate of $20g/kgW^{0.75}$ and from 91-120 d post-mating at the rate of $40g/kgW^{0.75}$. LH group was provided with concentrate from 61 to 120 d post-mating and 121 to term at the rate of 20 g and $40g/kgW^{0.75}$, respectively. Mean total dry matter and concentrate intake ($g/kgW^{0.75}$) was significantly higher on HH in comparison to comparable intake of HL and LH treatments, however, wheat straw followed the reverse trend. Haematological and biochemical parameters except serum glucose, total serum protein and A:G ratio did not differ significantly among dietary treatments. The gross gain in weight, products of pregnancy at 21 weeks of gestation, pregnant does average daily gain, birth weight of kids and survivability of kids were significantly lower in treatment HL in comparison to comparable values for HH and LH treatments. The net gain in gravid does was significantly higher in treatment HH than the comparable values obtained in HL and LH treatments. The last month of pregnancy was found to be nutritionally most sensitive period of gestation for native goats.

• 한국농림기상학회지
• /
• 제1권1호
• /
• pp.52-59
• /
• 1999

Vegetation canopy plays an important role in $CO_2$/$H_2$O exchange between the biosphere and the atmosphere by controlling leaf stomata. In this study, rice (Oryza sativa L.), a staple crop in Asia was investigated to formulate its single leaf model of photosynthesis and stomatal conductance. Photosynthesis and stomatal conductance were measured with a portable infrared gas analyzer system. Other plant and meteorological variables were also measured. To evaluate empirical constants in this biochemical leaf model, nonlinear least squares technique was used. The maximum catalytic activity of enzyme and the maximum rate of electron transport were $ 100\mu$㏖ $m^{-2}$ $s^{-1}$ and $140 \mu$㏖ m$^{-2}$ s$^{-1}$ (@ 35$^{\circ}C$), respectively. The empirical constants, m and b, associated with stomatal conductance model were 9.7 and $0.06 m^{-2}$ $s^{-1}$ , respectively. On a leaf scale, agreements between the modeled and the measured values of photosynthesis and stomatal conductance were on average within 20%, and the simulation of diurnal variation was also satisfactory On a canopy scale, the Simple Biosphere model(SiB2) was tested using the derived parameters. The modeled energy fluxes were compared against the micrometeorologically measured fluxes over a rice canopy. Agreements between the modeled and the measured values of net radiation, sensible heat and latent heat fluxes, and $CO_2$ flux (i.e., net canopy photosynthesis) were on average within 25%.

• 한국동물위생학회지
• /
• 제15권2호
• /
• pp.215-225
• /
• 1992

To estimate pollution status of livestock wastewater on four piggeries and one abattoir in Taegu area, physicochemical water analysis such as pH, suspended solid(SS), biochemical oxygen demand(BOD) and chemical oxygen demand(COD), and bacteriological examinations such as number of total viable cells and number of coliform with or without antibiotic resistance were carried out. The results obtained were as follows : The pH values of raw sewage ranged from 9.0 to 7.2 that of the effluent treated was lowed to 5.6~7.7. The SS values of raw sewage ranged from 5,275ppm to 120ppm and those of the efflunet decreased to 162~30ppm. The BOD values of raw sewage ranged 6,200ppm to 120ppm and those of the effluent treated decreased to 111 ~80ppm. The COD values of raw sewage ranged from 5,725ppm to 298ppm and those of the effluent decreased to 137~76ppm. The total viable cells of raw sewage ranged from $8.5{\times}11^{11}$/ml to $9.9{\times}10^7$/ml, those of the effluent decreased to $5.6{\times}10^6{\sim}4.2{\times}10^8/ml.$ The total coliforms of raw sewage ranged from $5.5{\times}10^9$/ml to $1.3{\times}10^5$/ml, those of the effluent decreased to $3.6{\times}10^4ml{\sim}9.0{\times}10^6$/ml. The incidence of streptomycin resistant coliforms was the highest(1.8~66.7%), and followed by tetracycline(1.7~64%), kanamycin(9.3~50.l%), ampicillin(0.06~45.5%) and chloramphenicol(14.3~33.5%) to total coliforms of raw sewage. The incidence of antibiotic resistant coliforms of raw sewage in farms ranged from 3.4~66.7% and that of abattoir's was 0.06% to 14.3%. Antibiotic resistant coliform counts of raw sewage ranged from 1.3$\times$10$^{8}$ /ml to 3.9$\times$10$^3$/ml, those of the effluent decreased to $3.0{\times}10^1{\sim}2.3{\times}10^5/ml$.

• 생약학회지
• /
• 제27권4호
• /
• pp.309-315
• /
• 1996

As part of our search for less toxic antimicrobial agents from natural resources, antimicrobial activity of rutin isolated from Sophora japonica was tested in vitro against four kinds of gram positive bacteria and four kinds of gram negative bacteria by serial broth dilution method. Among eight kinds of bacteria tested, the antimicrobial activity of rutin was the most potent against Mycobacterium smegmatis showing MIC of $375\;{\mu}g/ml$. The acute toxicity of rutin was examined in mice and rats. and $LD_{50}$ value administered intraperitoneally in mice was 650 mg/kg(Confidence limit: 894-1,473 mg/kg). There were no significant changes in serum biochemical values and histopathological changes as compared with those of control after intraperitoneal administration with rutin in rats.

• Journal of Nutrition and Health
• /
• 제21권4호
• /
• pp.213-222
• /
• 1988

The purpose of this study was to investigate physical condition, physical fitness, sociodemographic factors, biochemical factors and personality factors of 5th grade students of elementary school. The number of students surveyed was 760 from each school of urban, middle and rural areas. All data analysis was done by BMI group which is based on previous study. 1) The children whose parents were on low education level and mother had a job had lower BMI values than others. Nine percent of male and 21% of female subjects skipped breakfast almost everyday. The 21.7% of all subjects regularly took nutritive pills, which had no difference in various BMI groups. 2) The physical condition of children had a high correlation with that of parents. 3) The physical fitness in BMI 5 groups was weaker than other groups, especially in male. 4) The contents of blood hemoglobin, cholesterol and glucose and hematocrit value were estimated. In female, the values of hemoglobin content and hematocrit had significant difference between BMI groups, but there are no trends. 5) The impulsiveness of male was the highest in BMI 1 group and the lowest in BMI 5 group among 5 groups. Besides, general activity, reflectivity and sociality in BMI 5 group had a low level. In female, personality factors except sociality didn't show any considerable difference.

• 대한한의학회지
• /
• 제30권3호
• /
• pp.79-85
• /
• 2009

Aim : To evaluate the pharmaceutical safety of the herbal formula Myelophil, composed of Astragali Radix and Salviae Radix, via systemic subacute toxicological study using SD rats. Methods : Forty male and 40 female SD rats were fed with Myelophil (5000, 2500 or 1250 mg/10 mL/kg) or distilled water for four weeks. Adverse effects were examined intensively by comparing the differences between normal and drug-administered groups using clinical signs, necropsies, histopathologic findings, hematology, urinalysis, and blood biochemical analysis. Results : No altered clinical symptoms including body weight, diarrhea, anorexia, death, and abnormal necropsy of major organs were observed in male or female rats. No drug-induced abnormalities in histopathological finding, hematological values, urinalysis, and blood biochemical values were found at any doses of Myelophil. Conclusion : Myelophil should be very safe when used in a clinical application with a wide therapeutic index.

• International Journal of Advanced Culture Technology
• /
• 제10권2호
• /
• pp.201-212
• /
• 2022

With the development of sequencing technology, there is a need for technology to predict the function of the protein sequence. Enzyme Commission (EC) numbers are becoming markers that distinguish the function of the sequence. In particular, many researchers are researching various methods of predicting the EC numbers of protein sequences based on deep learning. However, as studies using various methods exist, a problem arises, in which the exact prediction result of the sequence is unknown. To solve this problem, this paper proposes an All Enzyme Commission (AEC) algorithm. The proposed AEC is an algorithm that executes various prediction methods and integrates the results when predicting sequences. This algorithm uses duplicates to give more weights when duplicate values are obtained from multiple methods. The largest value, among the final prediction result values for each method to which the weight is applied, is the final prediction result. Moreover, for the convenience of researchers, the proposed algorithm is provided through the AllEC web services. They can use the algorithms regardless of the operating systems, installation, or operating environment.