• Journal of Korean Society of Environmental Engineers
• /
• v.27 no.1
• /
• pp.11-16
• /
• 2005

Humic substances(HS) from raw and process waters at a conventional water treatment plant were isolated and extracted by physicochemical fractionation methods to investigate their characteristics. They are characterized for their functionality, chemical composition, and spectroscopic characteristics using FT-IR(Fourier transform infrared) and $^1H-NMR$(proton nuclear magnetic resonance) spectroscopy. Humic fraction gradually decreased from 47.2% to 26.4%(from 0.97 to 0.54 mgC/L) through conventional water treatment processes. Concentration of phenolic groups in the HS fraction gradually decreased from 60.5% to 21.8%(from 12.2 to $6.0\;{\mu}M/L$ as phenolic-OH) through water treatment. In the case of carboxylic groups, the concentration increased from 39.5% to 46.9%(from 7.9 to $10.6\;{\mu}M/L$ as COOH) by pre-chlorination, but gradually decreased to 34.2%($9.4\;{\mu}M/L$ as COOH) through sedimentation and sand filtration. From the results of the FT-IR and $^1H-NMR$ spectra of HS, the content of carboxylic groups increased and ratio of aliphatic protons to aromatic protons($P_{Al}/P_{Ar}$) also increased through water treatment, which indicated the increase of aliphatic compounds.

• The Korean Journal of Food And Nutrition
• /
• v.25 no.4
• /
• pp.833-841
• /
• 2012

This study was conducted to investigate rheological and sensory characteristics of fish paste prepared with Curcuma longa L. powder (0, 1, 3, 5, 7%). The moisture content of the fish paste ranged from 71.35 to 72.97%. Increasing the amount of Curcuma longa L. powder in the fish paste tended to decrease the pH value and the folding test good score in all samples. Increasing the amount of Curcuma longa L. powder in the fish paste also tended to decrease the lightness (L) in the hunter color value, but to increase the redness (a) and yellowness (b). For the textural characteristics, the addition of Curcuma longa L. powder increased the strength and decreased the springiness. In a sensory evaluation, the addition of 3% Curcuma longa L. powder had the best score in taste and overall preference. Therefore, this results suggest that adding 3% Curcuma longa L. powder would be feasible for making Curcuma longa L. fish paste.

• Advances in environmental research
• /
• v.5 no.3
• /
• pp.189-200
• /
• 2016

This study aimed at advanced oxidation of hetero tri-functional reactive dye Acid orange 7 using photo-Fenton conditions in a lab-scale experiment. Decolourisation of Acid Orange 7 dye by Fenton's process was dependent on concentration of Hydrogen peroxide, Ferrous sulphate, pH, and contact time. A $2^3$ factorial design was used to evaluate the effects of these key factors: pH, Fe(II), and $H_2O_2$ concentration, for a dye concentration of 50 mg/L with COD of 340 mg/L at pH 3.0. The response function was removal of colour under optimised conditions; pH 3.0, [Fe(II)] 40.83 mg/L, [$H_2O_2$] 4.97 mmol/L; 13.6 min. of treatment resulting in 100% colour removal. The final COD of treated wastewater was nil suggesting that AOP is a potentially useful process of color removal and dye degradation/mineralisation of effluent having AO7. Minimum contact time for complete decolourisation was at 5 mmol/l $H_2O_2$ concentration. Increase in $FeSO_4$ (mg/l) concentration resulted in decrease of time for complete decolourisation. Box-Behnken Design was used to optimize the process variables. Maximum and minimum levels of pH (3-5), $H_2O_2$ (4-6 mmol/l), $FeSO_4$ (30-46 mg/l) and contact time (5-15 minutes) were used. The statistical analysis revealed a value of 0.88 for coefficient of regression ($R^2$) indicating a good fit of model. Calculated F-value was found higher than the tabulated value confirming to significance of the model. Based on student's t-test, Ferrous sulphate, pH, and contact time have a positive effect on the percent decolourisation of Acid Orange 7.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.6 no.2
• /
• pp.85-97
• /
• 2002

In this paper, finite volume element methods for nonlinear parabolic problems are proposed and analyzed. Optimal order error estimates in $W^{1,p}$ and $L_p$ are derived for $2{\leq}p{\leq}{\infty}$. In addition, superconvergence for the error between the approximation solution and the generalized elliptic projection of the exact solution (or and the finite element solution) is also obtained.

• Korean journal of food and cookery science
• /
• v.7 no.4
• /
• pp.87-91
• /
• 1991

This study was performed to examine the mineral binding properties of total dietary fiber (TDF) and acid detergent fiber (ADF) from Job's tears (Yulmoo: Coix lachryma-jobi L. var. Ma-yuen Stapf.) bran. The endogenous Ca and Fe contents of dietary fiber extracted from Yulmoo bran were measured by atomic absorption spectrophotometer (AAS). Ca contents were 40, 118.6$\mu\textrm{g}$ Ca/g TDF and 131.6 $\mu\textrm{g}$ Ca/g ADF. Fe contents were 1,219.7 $\mu\textrm{g}$ Fe/g TDF and 277.5 $\mu\textrm{g}$ Fe/g ADF. The calcium binding capacities of dietary fiber at pH 5.0, 6.0, 7.0 were 50.77, 77.57, 86.64% for TDF, 40.27, 51.42, 40.90% for ADF, respectively. The iron binding capacity of dietary fiber at pH 5.0~7.0 was 95~97% for TDF and 85~95% for ADF.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.30 no.4
• /
• pp.109-122
• /
• 2022

Currently, most of the pig manure generated from pig farms in Korea is in the form of a slurry with a moisture content of about 97%. Pig manure slurry is a mixture of pig manure and cleaning water in the pig house. In this study, changes in properties of pig manure liquid fertilizer according to whether air was supplied or not and with the passage of storage period were analyzed for 120 days. During the experimental period, the degree of maturity of the pig manure liquid fertilizer was higher in the experimental closed batch reactors supplied with air than in the same type reactors not supplied with air. As the liquid fertilizer storage period elapsed, there was a tendency that liquid fertilizer was converted to a state of complete maturity. In the batch reactor in which air was supplied, the moisture content of pig manure slurry, which had a moisture content of 97.90%, was reduced to 96.82% at the end of the experiment. On the other hand, the moisture content in the reactor without air was reduced to 97.33%. The pH of the liquid fertilizer, which was 8.82 at the start of the experiment, changed to 7.57 in the reactor with air supplied and 8.75 in the reactor without air at the completion of the experiment. The nitrogen content in the liquid fertilizer was 0.198 mg/L on average at the start of the experiment and it was lowered to 0.076 mg/L in the air supplied reactor at the end of the experiment. On the other hand, the nitrogen content of the liquid fertilizer was lowered to 0.121 mg/L in the reactor to which air was not supplied. The phosphoric acid (P₂O₅) concentration in the liquid decreased higher in the liquid fertilizer filled in the reactor without air than the liquid fertilizer filled in the reactor with air supplied as the storage period elapsed. Considering the experimental results, it is considered that the quality of pig manure liquid fertilizer is improved when air is supplied to pig manure slurry and the storage period of pig manure slurry is longer.

• Proceedings of the Korea Society of Poultry Science Conference
• /
• 2004.11a
• /
• pp.69-79
• /
• 2004

A feeding trial was conducted to determine whether dietary vitamin C (200 mg/kg) and vitamin E (250 mg/kg) prevent any drops in egg shell quality under heat stress in broiler breeder hens. One hundred and sixty molted Ross broiler breeders were housed randomly in an individual cage at 83 weeks of age. Four dietary treatments with forty hens and four replications per treatment were control (no additional vitamins). vitamin C-. or vitamin E-supplemented. and combined supplementation of the two vitamins. After a ten-day-adaptation period at 25 $^{\circ}C$. the ambient temperature was kept at 32 $^{\circ}C$ for a three-week-testing period. Egg production dropped dramatically over week but it did not show a significant change among treatments (P<0.05). However. egg weight. SG. shell thickness. SWUSA. puncture force and shell breaking strength of the birds fed the diet with the combined vitamins C and E were significantly improved than those fed the basal diet during the heat stress period (P<0.05). The hens fed the vitamin C supplemented diet showed a tibia breaking strength of 37.16 kg statistically higher than those of the basal and the vitamin E supplemented groups (P<0.05). The hens fed the basal diet showed higher serum corticosterone levels. a mean of 5.97 ng/ml. than those of the rest of treatments (P<0.05). The heat stress elevated heterophils but decreased lymphocytes in serum. and it changed H/L ratios of all the treatments. The increases in H/L ratios were alleviated in the bird by feeding vitamin C and/or vitamin E supplemented diets. but they did not differ significantly (P<0.05). In conclusion. vitamins C (200 mg/kg) and/or E (250 mg/kg) supplementation to diets could prevent drops in egg shell quality and tibia bone strength by alleviating stressful effects from high temperature in broiler breeder hens.

• Journal of the East Asian Society of Dietary Life
• /
• v.19 no.6
• /
• pp.981-986
• /
• 2009

The quality characteristics and antioxidative activity of garlic pickles prepared with persimmon vinegar with or without Maesil (Japanese apricot) juice were investigated. Heat treated garlic cloves ($110^{\circ}C$, 5 min and then rapidly cooling) were salted with NaCl and $CaCl_2$, and then soaked in pickling solution, and stored at $20^{\circ}C$. The pH of the garlic pickles initially ranged from 2.36~3.24, after which the pH slightly increased to 3.22~4.13 during storage, while the acidity was decreased to 1~1.97. Throughout the entire storage periods, the acidity of the garlic pickle containing persimmon vinegar and Maesil was the highest (1.97%). The hardness of the control sample (non heated garlic) decreased during storage, whereas the hardness of all the heat treated groups did not change after 21 days of storage. Moreover, the chewiness of the persimmon vinegar+Maesil group was the highest among the groups. The Hunter color L value of garlic pickles decreased during storage, while the b value (yellowness) increased for all groups except the two persimmon groups. The $IC_{50}$ of the DPPH radical scavanging activity of garlic pickles at 5 day of storage was 85.98~97.81 mg/mL. However, the antioxidative activity of garlic pickles gradually increased with longer storage times. The persimmon vinegar+Maesil group showed the highest antioxidative activity. Results from the sensory evaluation showed that scores of flavor, taste and over-all preference were higher for the persimmon vinegar+Maesil group than the other groups (p<0.05).

• Food Science and Preservation
• /
• v.16 no.1
• /
• pp.101-108
• /
• 2009

The purpose of this study was to measure flavonoid and polyphenol contents, and physiological activities of various extracts from Vitex rotundifolia seeds (known as Man Hyung Ja). We obtained three extracts using water (WE), ethanol (EE) and hot water (HWE). The EE sample had the highest flavonoid content of 31.05 mg/g. Polyphenol contents of WE and HWE were 186.69 mg/g and 182.55 mg/g, respectively. HWE had the highest superoxide dismutase (SOD)-like activity, at 83.40%. The electron donating abilities (EDA) were $91.14{\sim}95.97%$ at the concentration of 1.0 mg/mL, and all of extracts showed more than 88% EDA even at a concentration of 0.1 mg/mL. The inhibitory rates of xanthine oxidase were $94.02{\sim}97.51%$ when 1.0 mg/mL extracts were used, and all extracts showed more than 90% inhibition at 0.5 mg/mL. The nitrite scavenging abilities were $59.27{\sim}86.61%$ at pH 1.2 and 1.0 mg/mL extract concentration; these abilities decreased as pH increased. Tyrosinase inhibition activities of HWE and WE were 48.58% and 46.67%, respectively. These results indicate that Vitex rotundifolia seeds extract might be an effective antioxidative activity.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.23 no.2
• /
• pp.97-117
• /
• 1997

L-Ascorbic acid 및 그 유도체는 항산화 작용과 미백작용 및 섬유아세포의 생장 촉진과 콜라젠 생합성의 증가시키는 효과가 있으므로 화장품에서 오래 전부터 사용되어 왔다. 본 연구에서는 생체에 대한 안전성과 안정성이 우수한 L-Ascorbic acid 유도체를 개발하기 위하여 인지질과 유사하게 L-Ascorbic acid 에 3-Aminopropane phosphoric acid를 결합하여 L-Ascorbic acid-3-aminopropane phosphoric acid diester를 합성하였다. ASA-APPA 는 2-Chlorotetrahydro-2H-1, 3, 2-oxazaphosphorine P-oxide 와 5, 6-isopropylidene L-Ascorbic acid 를 반응 시킨 후 산 사수분해 반응을 통하여 얻을 수 있었다. ASA-APPA는 수용액에서 안정성이 우수하였으며, 독성실험에서 무독성 물질이며, 인체 첩포 실험에서도 무자극 물질임을 확인하였다. 그리고, ASA-APPA 는 L-Ascorbic acid 와 3-APPA 의 혼합물과 거의 유사한 섬유아세포의 증식효과를 나타내었으며, melanoma 에 대한 멜라닌 생성 억제 실험에서 L-Ascorbic acid phosphate magnesium salt 와 유사한 효과를 보였다. 따라서 ASA-APPA 는 멜라닌 생성 억제 효과와 섬유아세포의 증식 효과를 갖는 새로운 화장품 원료로서 사용이 가능할 것으로 생각된다.