• Journal of Environmental Science International
• /
• v.25 no.5
• /
• pp.625-633
• /
• 2016

This study was conducted to investigate the influence of hydrophilic polymer (HP) mixture ratio (Control, 1.0%, 2.5%, 5.0%, and 10.0%) on growth of eggplant (Solanum melongena) for lower maintenance urban agriculture via green roofs. Although it was not statistically significant (p > 0.05), substrate temperature was decreased as hydrophilic polymer mixture ratio were increased. High substrate water content (95%) was found consistently in growing media under elevated hydrophilic polymer mixture ratio at over 5% during the entire growing period. Substrate electronic conductivity was increased as hydrophilic polymer mixture ratio were increased. Growth index was decreased as hydrophilic polymer mixture ratio was increased. It was reduced about 1/3 and 1/5 compared to that of Control in HP5.0 and HP10.0 treatment plants, respectively. Number of leaves, leaf length, and leaf width were decreased in following order: Control> HP1.0> HP2.5> HP5.0> HP10.0 treatments. There numbers were significantly lower in HP5.0 and HP10.0 treatment plants. Dry weight of shoot and root were decreased as hydrophilic polymer mixture ratio was increased. They were reduced by 1/4 compared to those of Control treatment plants. In addition, visual value was decreased as hydrophilic polymer mixture ratio was increased. Plants grown in HP1.0, HP2.5, and HP5.0 treatments all survived. However, plants grown in the HP10.0 treatment had the lowest survival rate (56%) after 3 months of growing. These results indicate that the advantage of adding hydrophilic polymer to green roof growing media may greater during dry periods. However, the proper mixture proportion of hydrophilic polymer should be determined according to different characteristics of growing media and plant species.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.4
• /
• pp.711-715
• /
• 2004

The stability of 80% ethanol-soluble pigments from Monasus purpureus CBS 281.34 was investigated according to storage temperature, pH and addition of organic acid. Also, the stability of ethanol-soluble pigment in aqueous system was examined after the addition of distilled water in the range of 0∼80% during the storage at 1$0^{\circ}C$ and 2$0^{\circ}C$ for 4 weeks with water soluble pigment. The heat stability was the highest (9.74%) when the 80% ethanol-soluble pigments were stored at 1$0^{\circ}C$ for 4 weeks. However, the 80% ethanol-soluble pigments stored at 6$0^{\circ}C$ and 8$0^{\circ}C$ for 24 h and 12 h greatly decreased by 23.06% and 30.36%, respectively. Although the 80% ethanol-soluble pigments were stable in the range of pH 4∼8, the degradation rate of pigment increased at pH 2 and PH 10.80% ethanol extract was adjusted to PH 4 by adding organic acids. The rate of pigment degradation was not different from control for 4 weeks. Red pigment was stable in the treatment of organic acids. And the stability of ethanol-soluble pigment in aqueous system was gradually decreased as the pigment content and storage time increased. Additionally, the stability of ethanol-soluble pigment was higher at 1$0^{\circ}C$ than at 2$0^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.2
• /
• pp.165-174
• /
• 1993

This work was conducted to study the use of L. acidophilus, which exists in humun intestine for the fermentation of Chinese cabbage kimchi. The changes in vitamins, the number of microflora and sensory quality were observed during fermentation after the microflora which was not related to kimchi fermentation was eliminated by treatment with ozone water or ozone gas. The growth rate of L. acidophilus in the cabbage juice was higher than that in MRS broth. The growth of L. acidophilus was slightly promoted by adding 1~2% hot pepper powder while that was inhibited by ginger and garlic. Therefore, it was shown that the regulation of fermentation was possible by addition of spices. The result of treating spice with ozone gas and ozone water 6mg/L/sec for 1 hour was that the survival ratio of total microflora was 6~20%. When L. acidophilus was added to materials after ozone treatment, the fermentation rate was improved and the polysaccharides in the cell wall were used when the usable free sugar was all consumed. The contents of vitamin B$_1$ and C in the ozone treated kimchi was higher than in the control.

• Clean Technology
• /
• v.18 no.1
• /
• pp.57-62
• /
• 2012

Aqueous poly (vinyl alcohol) (PVA) solution was modified by using hydrophobic vinyltriethoxysilane (VTEOS) and then adding different amounts of poly (acrylic acid) (PAA) to the resulting solution. Thermal and mechanical properties, contact angle, water vapor transmission rate (MVTR) and oxygen gas transmission rate ($O_2TR$) of the film samples fabricated by these solutions were investigated. The glass transition temperature (Tg) of the VTEOS-modified films was sightly increased and the value remained unchanged according to the amount of PAA. The tensile strength of the VTEOS-modified films was found to be 9.48~10.72 $kg/mm^2$ which showed no significant difference compared with that of PVA. The film prepared with VTEOS-modified PVA/PAA (= 90/10), of which the swelling and solubility were measured to be 198% and 0%, respectively, showed improved water-resistance. The MVTR and $O_2TR$ for the PET film (thickness 50 ${\mu}m$) coated with VTEOS-modified PVA/PAA (= 90/10) film (thickness 2.5 ${\mu}m$) were measured to be 11.04 $g/m^2/day$ and 3.1 $cc/m^2/day$, respectively.

• Food Science and Preservation
• /
• v.12 no.6
• /
• pp.583-590
• /
• 2005

Dough fermentation characteristics and quality characteristics of bread added with different concentration(0, 30, 40 and $50\%$ against water) of submerged-culture broth of Fomitopsis pinicola mycelium (CM) were investigated There were positive correlations between CM concentration and dough pH(r=0.98), acidity(r=-0.88), dough thickness(r=0.95) and dough strength(r=0.95). Baking loss rate was decreased with increasing of CM concentration. There was no significant difference between loaf volume index and CM concentration ($30\~40\%$, but the index of CM $50\%$ bread was lower than that of control. L* value of top crust in the CM $50\%$ bread was significantly lower than those of CM $0\~40\%$ bread, while the value of internal tissue was increased with increasing of CM concentration. In the CM $30\~40\%$ bread, hardness was lower, but there were no significant difference in cohesiveness, springiness, chewiness and brittleness compared with control. Appearance, color, taste, texture and overall acceptability of CM $30\~40\%$ bread were similar to those of control. In the results estimated by correlation analysis, the increased pH of the dough by adding CM allowed lowering hardness of the bread By adding CM in bread, retrogradations were delayed, and growth of mold was decreased during storage. In conclusion, the optimum concentration of CM in bread which showed anti-diabetic effect as well as not dropped quality characteristics were $30\~40\%$.

• Korean Journal of Environmental Agriculture
• /
• v.31 no.3
• /
• pp.212-216
• /
• 2012

BACKGROUND: Green manure and graminaceousmanure crops have several benefits, such as improving soil physical and chemical properties and utilizing excessive greenhouse nutrients that they have a potential to be a water pollutant source. METHODS AND RESULTS: The objective of this study was to investigate nitrogen (N) supplying capabilities of green manure and graminaceous manure crops for lettuce (Lactuca sativa L.) and Chinese cabbage (Brassica campestris L.) grown under greenhouse conditions. For this two leguminous manures (Crotalaria juncea (Cr.) and Sesbaniaexaltata (Se.)) and two graminaceous manures (Sorghum bicolor; Haussolgo(Ha.) and Sudangrass (Sg.)) in the greenhouse were grown, cut, and incorporated into the greenhouse soil before planting. Chemical nitrogen (N) fertilizer rate was estimated based on N recommendation for lettuce and Chinese cabbage. 100% of the N recommended rates (1N) were 70 kg N $ha^{-1}$ for lettuce and 60 kg N $ha^{-1}$ for Chinese cabbage and 50% of the N recommendation rates (0.5N) were 35 kg N $ha^{-1}$ for lettuce and 30 kg N $ha^{-1}$ for Chinese cabbage. Nitrogen treatments were control (0N), Cr., Se., Cr + 0.5 N, Se + 0.5 N, Ha + 0.5 N, Sg + 0.5 N, and N recommendation rate (1N). Incorporated N from green manure and graminaceous manure crops were 130, 116, 93, and 87 kg N $ha^{-1}$ for Cr., Se., Ha., and Sg., respectively. Lettuce and Chinese cabbage were grown after incorporated green manure crops into the greenhouse soil. There was no significant difference in lettuce and Chinese cabbage yields under N treatments except control (0 kg/ha). Nitrogen use efficiency (NUE)was from 44% to 73% and the highest NUE was under Se. treatment. Although yields were not statistically different under N treatments except control, actual yield increase ranged from 170 to 1,100 kg/ha for lettuce and ranged from 2,770 to 5,210 kg/ha for Chinese cabbage compared to yield under N recommendation rate. Estimated economic benefit from this would be higher approximately between \2,770,000 and \5,210,000/ha under N treatments except control than the N recommendation rate. CONCLUSION: These results suggest that incorporating green manure crops, such as Cr. and SeSe. into soil or adding 0.5 N after incorporation of them can be beneficial in many ways in that it increases economic return because of yield increase, reduces the use of chemical N, and decreases the negative environmental impact on water quality because excessive N in the greenhouse soil can be used by green manure crops during the fallow.

• Applied Chemistry for Engineering
• /
• v.32 no.3
• /
• pp.320-325
• /
• 2021

In this study, an optimization for the production of water emulsion was designed by adding an extract of wheat sprout, which is known to contain a large amount of antioxidants. The central composite design of reaction surface analysis method (CCD-RSM) was used for the optimization process. The amount of emulsifier, emulsification time, and added amount of wheat sprout extract were selected as independent variables based on our preliminary experiments. The mean droplet size (MDS), viscosity, and emulsion stability index (ESI) were set as the responses to evaluate the stability of the emulsion. For each independent variable, the P-value and coefficient of determination were evaluated to verify the reliability of the experiments. From the result of CCD-RSM, optimum conditions for the emulsification were determined as 23.6 min, 7.7 wt.%, and 3.9 wt.% for the emulsification time, amount of emulsifier, and amount of sprout, respectively. From the optimized condition obtained, MDS, viscosity, and ESI after 7 days from reaction were estimated as 252.3 nm, 616.7 cP, and 88.7%, respectively. The overall satisfaction was 0.9137, which supported the validity of the experiments, and the error rate was measured at 0.5% or less by advancing the experiments. Therefore, an optimized process for producing an emulsion by adding the malt extract was designed by the CCD-RSM.

• Korean Journal of Agricultural Science
• /
• v.13 no.1
• /
• pp.90-102
• /
• 1986

This study was performed to obtain the basic data which can be applied to the use of concretes. The data was based on the properties of concrectes depending upon water-cement ratios and addings to compare those of plain concrete. The results obtained were summarized as follows; 1. In case the proper quantity of water reducing agent was added, unit weight of water is decreased to 12.9% with WR-LG of water reducing set standarding agent and to 8.6% with HF-SP of high fluid agent and to 17.2% with AH-WR of water reducing set accelerating agent, respectively, as compared with plain concrete. With the increase of water reducing agent content unit weight of water was greatly decreased. 2. The adding rate of water reducing agent which produce maximum strength was 0.2% with WR-LG and 0.4% with HF-SP and AH-WR, respectively. The increasing rates of strengths were showed that WR-LG is 24.1% and that HF-SP is 41.8% and that AH-WR is 43.3%, respectively, as compared with plain concrete. 3. The correlations between compressive and tensile strength were highly significant as a straight line. the multiple regression equations of compressive and tensile strength were computed with the variables of curing age and addition of water reducing agent. They were highly significant. 4. In case the proper quantity of water reducing agent was added, the correlations between water-cement ratio and compressive strength were highly significant as a straight line. The increasing rates of strength were showed higher than the decreasing rates of water cement-ratio.

• Korean Journal of Ecology and Environment
• /
• v.56 no.3
• /
• pp.187-195
• /
• 2023

Almost all of the water from agricultural dams located to the upper of the Yeongsan river is supplied as irrigation water for farmland and thus is not discharged to the main stream of the river. Also, most of the irrigation water does not return to the river after use, adding to the lack of flow in the main stream. As a result, the water quality and aquatic health of the river have become the poorest among the four major rivers in Korea. Therefore, in this study, several strategies for water quality improvement of the river were developed considering pollution reduction and flow rate increase, and their effect analysis was performed using a water quality model. The results of this study showed that the target water quality of the Yeongsan river could be achieved if flow increase strategies (FISs) are intensively pursued in parallel with pollution reduction. The reason is because the water quality of the river has been steadily improved through pollution reduction but this method is now nearing the limit. In addition, rainfall-related FISs such as dam construction and water distribution adjustment may be less effective or lost if a megadrought continues due to climate change and then rainfall does not occur for a long time. Therefore, in the future, if the application conditions for the FISs are similar, the seawater desalination facility, which is independent of rainfall, should be considered as the priority installation target among the FISs. The reason is that seawater desalination facilities can replace the water supply function of dams, which are difficult to newly build in Korea, and can be useful as a climate change adaptation facility by preventing water-related disasters in the event of a long-term megadrought.

• Journal of Microbiology and Biotechnology
• /
• v.30 no.4
• /
• pp.561-570
• /
• 2020

This study was designed to synthesize triglycerol monolaurate (TGML) with Lipozyme 435 as the catalyst, and explore its effects on the growth of Aspergillus parasiticus (A. parasiticus) and Aspergillus flavus (A. flavus) and the secretion of aflatoxin b1. The highest content of TGML (49.76%) was obtained at a molar ratio of triglycerol to lauric acid of 1.08, a reaction temperature of 84.93℃, a reaction time of 6 h and an enzyme dosage of 1.32%. After purification by molecular distillation combined with the washes with ethyl acetate and water, the purity of TGML reached 98.3%. Through characterization by electrospray-ionization mass spectrometry, infrared spectrum and nuclear magnetic resonance, the structure of TGML was identified as a linear triglycerol combined with lauroyl at the end. Finally, the inhibitory effects of TGML on the growths of A. parasiticus and A. flavus and the secretion of aflatoxin b1 were evaluated by measuring the colony diameter, the inhibition rate of mycelial growth and the content of mycotoxin in the media. The results indicated that TGML had a stronger inhibitory effects on colony growth and mycelial development of both toxic molds compared to sodium benzoate and potassium sorbate, and the secretions of toxins from A. parasiticus and A. flavus were completely suppressed when adding TGML at 10 and 5 mM, respectively. Based on the above results, TGML may be used as a substitute for traditional antifungal agents in the food industry.