• Journal of Applied Biological Chemistry
• /
• v.66
• /
• pp.81-89
• /
• 2023

The purpose of this study is to demonstrate the potential enhancement of the flavonoid contents from Agastache rugosa, which can be obtained as raw materials for functional products in the food medicine industry by identifying important factors for efficient preparation to save costs and time in terms of economic factors. For this reason, response surface methodology using Box-Behnken design was used to optimize the extraction conditions for the maximum yield of seven major compounds from A. rugosa. The optimum conditions were obtained with an ethanol concentration of 60.0%, a temperature of 50 ℃, and an extraction time of 33.6 min, meaning that the regression analysis fits the experimental data well. Under these conditions, the seven major compounds 1-7 had observed values of 2.169, 2.135, 0.697, 2.485, 0.105, 1.247, and 0.551%, respectively. These results show that the observed values are in good agreement with the predicted values in the regression model. This process for optimization study exhibited a basic protocol for obtaining stable ingredients from A. rugosa that are appropriate for the development of effective functional products.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.3
• /
• pp.213-218
• /
• 1993

An experiment was carried out to investigate the effects of plant growth regulators on the growth and fiber yield of ramie. Gibberellin (GA) and Atonic acid were applied at the various levels of application dates, application frequencies and concentration. Stem growth of ramie increased greatly by applying GA on the meristem of shoot apex. Among three treatments of application frequencies of GA, that is, one time application at the stage of stem length with 50cm, twice applications at the stem length of 50cm and 100cm, and three times applications at stem length of 50cm, 100cm and 150cm, stem growth increased more as application frequency increased. GA application is more effective on stem growth at the later stage of growth than the earlier growth stage. GA treatment of 100 to 300 ppm is more effective on stem elongation than 50 ppm, which was due on the elongation of internodes without increase in number of nodes. One time application of GA enhanced leaf growth more or less regardless of concentration, but GA was applied more frequently, leaf growth was inhibited more at higher concentration. Fiber yield was the highest at the treatment of three times application of GA with 100 ppm. This treatment also showed the highest percentage of fiber with 5.3%, which is much higher value compared with that of control treatment with 4.6%. Atonic acid was less effective on stem elongation than GA, but it also seemed to be effective on the enhancement of fiber development.

• Korean Chemical Engineering Research
• /
• v.52 no.4
• /
• pp.443-450
• /
• 2014

Selective catalytic reduction of nitrogen monoxide by hydrogen ($H_2$-SCR of NO) over platinum catalysts impregnated on zirconia-incorporated silica ($ZrO_2-SiO_2$) and manganese oxide ($MnO_x$) was investigated. $Pt-MnO_x$ catalyst showed low conversions and low yields of $N_2O$ and $NO_2$ at $100{\sim}350^{\circ}C$. On the other hand, NO conversions over $Pt/ZrO_2-SiO_2$ were very high, but $N_2O$ was predominantly produced at $100-150^{\circ}C$ and the yield of $NO_2$ increased with temperature at $200-300^{\circ}C$, resulting in poor $N_2$ yields. $Pt-MnO_x/ZrO_2-SiO_2$ exhibited a small enhancement in $N_2$ yield at $100-150^{\circ}C$ due to the synergy of $MnO_x$ and $ZrO_2-SiO_2$. The surface composition and oxidation state of the catalyst components and the acidity of the catalysts were examined. IR spectra of the adsorption of NO and their subsequent reactions with hydrogen on these catalysts were also recorded. The variations of conversion and product yield according to the catalyst components in the $H_2$-SCR of NO were discussed in relation to their catalytic roles.

• Applied Chemistry for Engineering
• /
• v.7 no.1
• /
• pp.75-82
• /
• 1996

Acrylic acid was graft-copolymerized on polyethylene film in the presence of additives such as acid and $FeSO_4(NH_4)_2SO_4{\cdot}6H_2O$ using peroxide grafting technique by ${\gamma}$-ray and electron beam, and the effect of $FeSO_4(NH_4)_2SO_4{\cdot}6H_2O$ and acid on the grafting yield was evaluated. The grafting mechanism and the physical property of grafted films were also examined. The results showed that the inclusion of $FeSO_4(NH_4)_2SO_4{\cdot}6H_2O$ in acidified acrylic acid grafting solution was extremely beneficial and led to a most unusual enhancement effect in the radiation grafting. In the other hand, inclusion of mineral acid in the grafting solution in the absence of $FeSO_4(NH_4)_2SO_4{\cdot}6H_2O$ could not lead to he suitable grafting reaction by the severe homopolymerization of acrylic acid. The addition of $H_2SO_4$, and HCl led to much higher grafting yield than $HNO_3$and $CH_3COOH$. It was shown that grafting yield of ${\gamma}$-ray irradiated-polyethylene was higher than that of electron beam irradiated polyethylene.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.29 no.5
• /
• pp.629-636
• /
• 1996

The developments of mariculture fisheries depend on both the natural environmental inputs such as sun, rain, wind, tide and the economic inputs such as ships, fuels, facilities, labor. for the enhancement of mariculture productivity in Deukryang Bay, a new attempt has been made to connect the environmental resources and the economic activity within one system. This study applies EMERGY analysis that evaluates environmental energies, fuels, goods and services in terms of solar emjoelus. In total EMERGY use $(69.65\times10^{20}\;sej/yr)$ the natural environment inputs is $78\%\;(54.60\times10^{20}\;sej/yr)$. This means that the mariculture in Deukryang Bay depends on mainly environmental resources. Net EMERGY yield ratio was 4.63 which indicated high value as a resource, EMERGY investment ratio was 0.28 that means to gain 3.6 times energy from the natural environment than those of economy. If the fisherie's products are made by renewable EMERGY input to Deukryang Bay, the calculated carrying capacity of fishes, crustaceans, shellfish and seaweeds were 1,140, 110, 1,553 and 9,074 ton/yr, respectively. If the quantity of renewable EMERGY input to mariculture grounds in Deukrysng Bay was calculated-based on only shellfish product, shellfish products was estimated as about 1,195 ton/yr.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.17 no.4
• /
• pp.112-121
• /
• 2009

To obtain basic design criteria for underground anaerobic digestion and enhance biogas production from swine slurry, a $20m^3$ underground anaerobic digester (UGAD) was constructed and operated at mesophilic ($31{\sim}37^{\circ}C$) temperature with an organic loading rate (OLR) at $23.6kgVS/m^3/day$. The average biogas and $CH_4$ production rate were observed at 8.62 and $5.78m^3/day$, respectively. The mean percentile of $CH_4$ and $CO_2$ were also observed at 67.5% and 19.6%. The relative biogas yield was explored at $733L/kg\;VS_{added}$ and $CH_4$ yield was at $495L/kg\;VS_{added}$ respectively. The removal rate of biochemical constituents and pathogens were noticed considerably at 68%, 74%, 79%, 86%, 89%, 81%, 55%, 79%, 98% and 100% on TS, VS, TSS, $BOD_5$, $TCOD_{cr}$, $SCOD_{cr}$, $NH_3-N$, available P, fecal coliforms and Salmonella, respectively. This study suggested that, the modified UGAD system is a greatly desirable for anaerobic digestion for swine slurry with regards to high methane yield and biodegradability.

• Journal of Korean Society on Water Environment
• /
• v.28 no.3
• /
• pp.375-383
• /
• 2012

Soil erosion has been emphasized as serious environmental problem affecting water quality in the receiving waterbodies. Recently, Best Management Practices (BMPs) have been applied at a field to reduce soil erosion and its effectiveness in soil erosion reduction has been monitored with various methods. Although monitoring at fields/watershed outlets would be accurate way for these ends, it is not possible at some fields/watersheds due to various limitations in direct monitoring. Thus modeling has been suggested as an alternative way to evaluate effects of the BMPs. Most models, which have been used in evaluating hydrology and water quality at a watershed, could not reflect rainfall intensity in runoff generation and soil erosion processes. In addition, source codes of these models are not always public for modification/enhancement. Thus, runoff-sediment evaluation system using hourly rainfall data and vegetated filter strip (VFS) evaluation module at field level were developed using open source MapWindow GIS component in this study. This evaluation system was applied to Bangdongri, Chuncheonsi to evaluate its prediction ability and VFS module in this study. The NSE and $R^2$ values for runoff estimation were 0.86 and 0.91, respectively, and measured and simulated sediment yield were 15.2 kg and 16.5 kg indicating this system, developed in this study, can be used to simulate runoff and sediment yield with acceptable accuracies. Nine VFS scenarios were evaluated for effectiveness of soil erosion reduction. Reduction efficiency of the VFS was high when sediment inflow was small. As shown in this study, this evaluation system can be used for evaluation BMPs with local rainfall intensity and variations considered with ease-of-use GIS interface.

• Korean Journal of Microbiology
• /
• v.37 no.2
• /
• pp.170-175
• /
• 2001

In order to produce xylitol with high yield, experiments were carried out to develope xylitol dehydrogenase(XDH) defective mutant from P. stipitis and to investigate the xylitol fermentation characteristics of mutant strain. After treatment of P. stipitis with EMS, mutant PXM-4 was selected based on te XDH activity and xylitol production capability. Among the tested cosubstrates, galactose was selected as an adequate cosub-strate on xylitol production of mutant PXM-4. But with the increase in the concentration of galactose in the medium, xylitol production was decreased because the transport of xylose into cell was inhibited by galactose. The optimal concentration of galactose for the production of xylitol using 20 g/ι xylose was 20 g/ι Under this condition, maximum concentration of xylitol and yield were 14.4 g/ι and 97%, respectively. In order to prevent the inhibitory effect of xylose transport by galactose, galactose was fed with low concentration and the concentration of xylitol produced was increased up to 25 g/ι.

• Korean Journal of Soil Science and Fertilizer
• /
• v.44 no.6
• /
• pp.1118-1123
• /
• 2011

The changes of available silicate (Avail. $SiO_2$) contents in paddy soils (sandy loam) were assessed from data of the 41 years fertilization plots in which the continuous rice cropping experiment started in 1954 at the National Academy of Agricultural Science. The treatments were no fertilization (O), inorganic fertilization (NPK), inorganic fertilizer plus rice straw compost (NPK+C), inorganic fertilizer plus silicate fertilizer as a soil amendment (NPK+S), inorganic fertilizer plus rice straw compost and silicate fertilizer (NPK+CS) and inorganic fertilizer plus rice straw compost, silicate fertilizer and lime (NPK+CSL). Available silicate contents in NPK+S, NPK+CS and NPK in surface soil reached at the highest content ($255{\sim}330mg\;kg^{-1}$) after 41 years and then levelled off. Available silicate contents in subsurface soil (25~30 cm) were higher in NPK+C and NPK+S treatments than those in other treatments. Continuous application of silicate fertilizer affected significantly on the levels of available silicate in surface and subsurface soils. Silicate uptake of top rice was more increased by 98% in NPK+CS and NPK+CSL over NPK. Grain yield also increased by 37~47% in NPK+CS and NPK+CSL as compared to NPK. The combined applications of inorganic fertilizers with silicate as a soil amendment are recommended as the best fertilization practice for fertilizer use efficiency, enhancement of soil fertility status in the continuous rice cropping system in Korea.

• Journal of Mushroom
• /
• v.21 no.4
• /
• pp.247-253
• /
• 2023

In this study, we examined the effects of gamma irradiation dosage on the mycelial growth of Auricularia auricula-judae and performed analyses of fruiting body yield, growth characteristics, taste, fragrance, and mineral composition. Assessments of mycelial growth in response to gamma irradiation at different intensities revealed an enhancement in the growth of fungi exposed to irradiation at 200 Gy. Fruiting body yield was also highest at 200 Gy, followed by 800 Gy and the control group. On the basis of these observations, we subsequently applied gamma ray doses of 200 and 800 Gy to examine the effects of irradiation on fungal quality characteristics. In terms of the taste of fruiting bodies, we detected no significant differences among the control, 200 Gy, and 800 Gy groups. Contrastingly, with respect to fragrance, we found that fungi treated with 200 Gy were characterized by a pattern that differed from those of the control and other treatment groups. Furthermore, whereas we detected no significant difference among treatments with respect total dietary fiber content, calcium content was found to be higher in the treatment groups compared with the control group, with the highest content being measured in fungi exposed to 800 Gy irradiation. Copper content was confirmed to be higher in the control group, whereas there were no significant differences between the fungi irradiated with 200 and 800 Gy. Contrastingly, the highest levels of zinc were detected in response to 200 Gy irradiation, followed by 800 Gy. Collectively, our findings thus indicate that gamma irradiation can contribute to promoting increases in the fruiting body yield and mineral contents of mushrooms.