• Food Science and Preservation
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• v.19 no.6
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• pp.951-956
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• 2012

In this study, the effects of the use of a starter on radish soaked at $4^{\circ}C$ for 28 days using two kinds of domestic sun-dried salt (white and gray salt) were determined. As a result, the moisture contents of the radish soaked with white and gray salt were 7.93 and 4.50%, respectively. The salinity levels were found to be equal (90%). No significant difference was found between the two groups in terms of the mineral contents of the salts therein ($37812.41{\pm}1922.95$ and $39755.13{\pm}1205.70$ mg/100 g, respectively). However, iron and zinc contents of gray salt were higher than those of white salt while the calcium, potassium, and magnesium contents were lower than those of white salt. After the addition of the starter, the sugar content increased, the pH decreased, and the total acidity rapidly decreased compared with the non-starter group during fermentation. The total microorganism count of the two groups increased during the fermentation period of 28 days. From the initial fermentation for 7 days, the lactic acid bacteria in the non-starter group increased while those in the leuconostoc starter group steadily increased within the whole fermentation period. The Leuconostoc spp. in non-starter group increased, but that in the starter group decreased to pH 4.0 on day 14.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.13-28
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• 2019

This study analyzed precipitation environment, heavy metal contamination, and mineral composition of white, reddish brown and mixed precipitates occurring at the Osip stream drainage, Gangwondo. Furthermore, spectral characteristics of the precipitates associated with heavy metal contamination and mineral composition was investigated based on spectroscopic analysis. The pH range of the precipitates was 4.43-6.91 for white precipitates, 7.74-7.94 for reddish brown precipitates, and 7.59-7.9 for the mixed precipitates, respectively. XRF analysis revealed that these precipitates were contaminated with Ni, Cu, Zn, and As. The white precipitates showed high Al concentration compared to reddish brown precipitates as much as 3.3 times, and the reddish brown precipitates showed high Fe concentration compared to white precipitates as much as 15 times. XRD analysis identified that the mineral composition of the white participates was aluminocoquimbite, gibbsite, quartz, saponite, and illite, and that of reddish brown precipitates was aluminum isopropoxide, kaolinite, goethite, dolomite, pyrophyllite, magnetite, quartz, calcite, pyrope. The mineral composition of the mixed precipitates was quartz, albite, and calcite. The spectral characteristics of the precipitates was manifested by gibbsite, saponite, illite for white precipitates, goethite, kaolinite, pyrophyllite for reddish brown precipitates, and albite for the mixed precipitates, respectively. The spectral reflectance of the precipitates decreased with increase in heavy metal contamination, and absorption depth of the precipitates indicated that the heavy metal ions were adsorbed to saponite and illite for white precipitates, and goethite and magnetite for reddish brown precipitates.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.565-576
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• 2021

This study was undertaken to measure changes in the composition of elk velvet antlers, by considering the part and growth days (40th day, 60th day). The collected samples were divided into the tip, upper, middle, and base part by position. Samples were analyzed for moisture, crude protein, crude fat, crude ash, crude fiber, pH, minerals, and fatty acid and amino acid contents. The amounts of crude protein and crude fat were determined to be highest at the tip of the velvet antler by position, whereas dry matter and crude ash were high at the base. Crude protein contents were increased in the upper part but were decreased at the base, when assessed by growth day. Conversely, crude fiber and crude ash were found to be increased at the base by growth day. The pH value was determined to be lower at the tip, but did not differ when evaluated by growth day. Mineral contents (Ca, P, K) differed significantly by growth day in the middle portion of the antler. Saturated fatty acids tended to increase by growth day, whereas unsaturated fatty acids showed a decreasing trend. However, no significant difference was obtained for any of the components. Most amino acids were found to be high in the 60 days velvet antler, except isoleucine (Ile), which showed low levels at day 60. These results provide information on the changes in the composition of antlers, in cases of early cutting.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.510-523
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• 2020

This study analyzed groundwater quality in hydroponic cultivation facilities. Through this study, the possibility of groundwater use was evaluated according to the quality of the groundwater for hydroponic cultivation facilities. Good groundwater quality, on average, is pH 6.61, EC 0.27 dS/m, NO3-N 7.64 mg/L, NH4+-N 0.80 mg/L, PO4-P 0.09 mg/L, K+ 6.26 mg/L, Ca2+ 18.57 mg/L, Mg2+ 4.38 mg/L, Na+ 20.85 mg/L, etc. All of these satisfy the water quality standard for raw water in nutrient cultivation. But in the case of farmers experiencing problems with groundwater quality, most of the items exceeded the water quality standard. As a result of the analysis, it was judged that purifying groundwater of unsuitable quality for crop cultivation, and using it as raw water, was effective in terms of water quality and soil purification. If an agricultural water purification system is constructed based on the results of this study, it is judged that the design will be easy because the items to be treated can be estimated. If a purification system is established, it can use groundwater directly in the facility and for horticulture. These study results will be available for use in sustainable agriculture and environments.

• Journal of the Korean Society of Food Culture
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• v.21 no.3
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• pp.297-302
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• 2006

This study has examined the physicochemical properties of the Pleurotus eryngii, including their proximate components, amount mineral content, total dietary fiber, total sugar, reducing sugar and free sugar. Additionally, it measured the P. egii ethanol extracts and the total amounts of polyphenol compounds as well as its electron donating ability (EDA) of the substance fraction (SF). The P. eryngii powder's moisture content was 9.0% and each of the other element content such as carbohydrate, crude protein, crude ash and crude fat was found to be 63.06%, 20.70%, 5.20% and 2.0% respectively. Potassium (K) was shown to be the greatest inorganic content and manganese (Mn) was the lowest. Furthermore fructose, galactose, glucose lactose and maltose free sugar content was found in this order. 387 mg% of the total amounts of polyphenol was found in the P. eryngii whole body ethanol extract, 158 mg% in the stipe extract, 593 mg% in the pileus extract and 607 mg% in the substance fraction (SF). Electron donating ability (EDA) was highest at 91.12% in the whole body extract and lowest at 62.90% in the stipe extract. Additionally, the EDA for substance fraction (SF) 0.02%-0.1% was found to be 57.78-77.33%, which was lower than the 0.02%-tocopherol (93.92%) and BHT (96.72%). From these results, it can be assumed that P. eryngii offers superior antioxidative effects with its high content of fiber, inorganic materials and total amounts of polyphenol as well as high electron donating ability (EDA), thereby making it ideal for use in functional foods and industrial materials.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.1-25
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• 1982

Limnological study on the physico-chemical properties and biological characteristics of the Lake Ok-Jeong was made from May 1980 to August 1981. For the planktonic organisms in the lake, species composition, seasonal change and diurnal vertical distribution based on the monthly plankton samples were investigated in conjunction with the physico-chemical properties of the body of water in the lake. Analysis of temperature revealed that there were three distinctive periods in terms of vertical mixing of the water column. During the winter season (November-March) the vertical column was completely mixed, and no temperature gradient was observed. In February temperature of the whole column from the surface to the bottom was $3.5^{\circ}C$, which was the minimum value. With seasonal warming in spring, surface water forms thermoclines at the depth of 0-10 m from April to June. In summer (July-October) the surface mixing layer was deepened to form a strong thermocline at the depth of 15-25 m. At this time surface water reached up to $28.2^{\circ}C$ in August, accompanied by a significant increase in the temperature of bottom layer. Maximum bottom temperature was $r5^{\circ}C$ which occurred in September, thus showing that this lake keeps a significant turbulence Aehgh the hypolimnial layer. As autumn cooling proceeded summer stratification was destroyed from the end of October resulting in vertical mixing. In surface layer seasonal changes of pH were within the range from 6.8 in January to 9.0 in guutuost. Thighest value observed in August was mainly due to the photosynthetic activity of the phytoplankton. In the surface layer DO was always saturated throughout the year. Particularly in winter (January-April) the surface water was oversaturated (Max. 15.2 ppm in March). Vertical variation of DO was not remarkable, and bottom water was fairly well oxygenated. Transparency was closely related to the phytoplankton bloom. The highest value (4.6 m) was recorded in February when the primary production was low. During summer transparency decreased hand the lowest value (0.9 m) was recorded in August. It is mainly due to the dense blooming of gnabaena spiroides var. crassa in the surface layer. A. The amount of inorganic matters (Ca, Mg, Fe) reveals that Lake Ok-Jeong is classified as a soft-water lake. The amount of Cl, $NO_3-N$ and COD in 1981 was slightly higher than those in 1980. Heavy metals (Zn, Cu, Pb, Cd and Hg) were not detectable throughout the study period. During the study period 107 species of planktonic organisms representing 72 genera were identified. They include 12 species of Cyanophyta, 19 species of Bacillariophyta, 23 species of Chlorophyta, 14 species of Protozoa, 29 species of Rotifera, 4 species of Cladocera and 6 species of Copepoda. Bimodal blooming of phytoplankton was observed. A large blooming ($1,504\times10^3\;cells/l$ in October) was observed from July to October; a small blooming was present ($236\times10^3\;cells/l$ in February) from January to April. The dominant phytoplankton species include Melosira granulata, Anabaena spiroides, Asterionella gracillima and Microcystis aeruginota, which were classified into three seasonal groups : summer group, winter group and the whole year group. The sumner group includes Melosira granulate and Anabaena spiroides ; the winter group includes Asterionella gracillima and Synedra acus, S. ulna: the whole year group includes Microtystis aeruginosa and Ankistrodesmus falcatus. It is noted that M. granulate tends to aggregate in the bottom layer from January to August. The dominant zooplankters were Thermocpclops taihokuensis, Difflugia corona, Bosmina longirostris, Bosminopsis deitersi, Keratelle quadrata and Asplanchna priodonta. A single peak of zooplankton growth was observed and maximum zooplankton occurrence was present in July. Diurnal vertical migration was revealed by Microcystis aeruginosa, M. incerta, Anabaena spiroides, Melosira granulata, and Bosmina longirostris. Of these, M. granulata descends to the bottom and forms aggregation after sunset. B. longirostris shows fairly typical nocturnal migration. They ascends to the surface after sunset and disperse in the whole water column during night. Foully one species of fish representing 31 genera were collected. Of these 13 species including Pseudoperilnmpus uyekii and Coreoleuciscus splendidus were indigenous species of Korean inland waters. The indicator species of water quality determination include Microcystis aeruginosa, Melosira granulata, Asterionelta gracillima, Brachionus calyciflorus, Filinia longiseta, Conochiloides natans, Asplanchna priodonta, Difflugia corona, Eudorina elegans, Ceratium hirundinella, Bosmina longirostris, Bosminopsis deitersi, Heliodiaptomus kikuchii and Thermocyclops taihokuensis. These species have been known the indicator groups which are commonly found in the eutrophic lakes. Based on these planktonic indicators Lake Ok-Jeong can be classified into an eutrophic lake.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.199-208
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• 1977

Activities of various hydrolytic enzymes produced by three plant pathogenic fungi, Sclerotium rolfsii Sacc., Sclerotinia sclerotiorum (Lieb.) deBary and Helminthosporium sigmoideum var. irregulare Crallery et Tullius, were measured. Activties and amounts of the enzymes in mycelia, cultural filtrates, and sclerotia(except of sclerotia of H. sigmoideum var. irregulare) were estimated at various pH levels in order to find out optimal pH for their enzymatic activities. Enzymes such as cellulase (ex), invertase, xylanase, $\beta-amylase$, polymethylgalacturonase, polygalacturonase, phosphatase and protease were estimated. Culture solution for production of enzymes was prepared by adding of 10g, D-glucose, 1.3g $NH_4NO_3,\; 0.5g\; MgSO_4,\;7H_2O,\; and\; 1.0g\; KH_2PO_4$ into 1 liter of potato decoction plus 2ml of micro element solution consisting of 0.2mg. Fe, 0.2mg Zn, and 0.1mg Mn as the sulphates into 1 liter of distilled water. All tested mycelia and cultural filtrates were obtained from the cultures incubarted in previous solution for ten days at $25^{\circ}C$, and sclerotia were harvested from PDA plates of 3. days old, The crude enzyme solutions were prepared according to the method of Miyazaki etal. Ten days after incubation, activities of Cx produced by Scl. sclerotiorum were higher than those of the other fung and each of Cx from three fungi showed different pH optima, such as S. rolfsii and Scl. schlerotiorum in acid side (around pH 3.0), H. sigmoideum var. irregulare in neutral side (around pH 6.3). Invertase activities of S. rolfsii were 20 times higher than those of the other fungi in all samples. All tested fungi, however, showed no significant difference between the enzymatic activities of their cultural filtrate and mycelia and the activities in sclerotia of S. rolfsii and Scl. sclerotiorum were hardly recognized. There were multiple peaks on the xylanase activity curves of three fungi in terms of pH values. High activities of the xylanase were revealed in sclerotia of S. rolfsii and Scl. sclerotiorum, and in mycelia of H. sigmoideum var. irregulare. The highest activities of $\beta-amylase$ were shown both in mycelia and cultural filtrate of H. sigmoideum var. irregulae among the tested fungi, and their optimal pH was 6.2 in both mycelia and cultural filtrate. In the S. rofsii and Sel. sclerotiorum, however, the activities of cultural filtrates were higher than those of the other fungi, and optimal pH was 3.0 and 6.2 for cultural filtrate and both mycelia and sclerotia, respectively. Activities of PMG were high in cultural filtrates of all tested fungi, especially in Scl. sclerotiorum and H. sigmoideum var. irregulare. Mycelia of themalso showed the considerable activities. Optimal pH for enzymatic activities were variable with thekind of fungi or with the samples measured. The highest activities of PG were presented by mycelia of S. rolfsii and Scl. sclerotiorum. $9.l\mu /min.\; and\; 9.5\mu g/min.$, respectively. Optimal pH for activity of PG in mycelia was around 4.5 in S. rolfsii and around 3.0 in Scl. sclerotiorum. Phosphatase of S. rolfsii and Scl. sclerotiorum was more active in acid side (optimal PH3. 5) and that of H. sigmoideum var. irregulare showed one peak each in acid, neutral and alkaline side. But the highest peak was at pH 9.5. Protease of all tested fungi was more active at pH 10.0, especially that of the cultural filtrate of H. sigmoideum var. irregualre.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.205-212
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• 2012

This study was performed to investigate the prevalence of metabolic syndrome (MS) and assess nutrient intake levels for the purpose of improving MS risk factors. The participants in this study were 512 adults consisting of 271 men and 241 women aged 30 and over, who visited a public health center for a medical check up. The diagnosis of MS subjects was adapted from the NCEP-ATPIII guidelines and the WHO Asia-Pacific Area criteria for obesity. The MS group was defined as subjects displaying three or more risk factors, and the non MS group was defined as those displaying two or less risk factors. A dietary survey was conducted using the 24-hour recall method. The number of subjects displaying MS syndrome factors was 158 (30.9%), broken down into, 89 men and 69 women. Regarding risk factors in the MS group, the prevalence of waist circumference was 40.5%, hypertension 34.2%, hyperglycemia 31.0%, low HDL-cholesterol 24.7%, and hypertriglycemia 19.6%. BMI, sistolic blood pressure, blood glocose, blood triglyceride, and blood HCL-cholesterol of the MS group were significantly higher compared to the non MS group. Male subjects in the MS group reported high intakes of cereals, sugar, fruits, meat and poultry, oil and fats, and beverages and total food intake was significantly higher compared to the non MS group. Women in the MS group reported high intakes of meat and poultry, milk and dairy products, beverages, and seasonings, and total food intake was higher compared to the non MS group. Dietary diversity score (DDS) was 3.82~4.04, which was not significant among the groups. In men, dietary variety score (DVS) was 16.3 in the MS group and 19.4 in the non MS group, whereas in women, the DVS was 15.2 in the non MS group and 17.0 in the MS group. In GMVDF pattern, 11111 pattern was 30.7%, followed by 01111 for men and 11101 for women. Calorie, fat, and cholesterol intakes in men as well as, calorie, fat, and folate intakes in women in the MS group were higher compared to the non MS group. Intakes of protein, P, Fe, Na, vitamin $B_1$, vitamin $B_2$, niacin, vitamin E, and Zn were higher than the KDRIs. On the other hand, intakes of Ca, K, fiber, vitamin $B_2$, and vitamin C were below the KDRIs. Intakes of lipids, animal food, Na, and cholesterol in the MS group were higher compared to the non MS group, whereas intake of dietary fiber was lower. Our results indicate that continuous, systematic nutritional education program must implemented to reduce the risk factors associated with MS.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.698-707
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• 2006

Precise and correct assessment of nutrient intake using appropriate dietary intake method is necessary to improve the nutritional status of the target people group. It is more likely so in elderly people since their dietary habits and inadequate nutrient intakes are of special concern even worse in rural areas. Two popular methods of gathering dietary intake are 24-hour recall and food frequency method (or food frequency questionnaire). In the present study, we conducted both 24-hour recall and food frequency method on 120 rural elderly people $(aged\;65{\sim}74\;years)$, 62 male and 58 female. The dietary intakes were analyzed and the correlation of the dietary intake between 24-hour recall and food frequency method to determine the reliability between two methods. Also each nutrient intake was compared to recommended dietary allowance (RDA) or nutrient reference value (NRV) as appropriate. Even correlation did not show significance between the two methods except for dietary fiber intake (0.65 at p<0.01) and energy-yielding nutrients which mostly showed similar results with nutrient intake level. These support the possible reliability between 24-hours record and food frequency method that is also shown on the cases of most mineral and vitamin intakes. Thus, the food frequency method used in this study for the assessment of nutrient intakes of the elderly people would be reliable for the assessment of the nutrient intake along with the 24-hour recall. Also, the present study results suggested that rural female elderly people would be under optimal nutriture status due to the lower food intake measured by 24-hour recall. The optimal food frequency method would be considered to be developed for the precise nutrient assessment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.455-462
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• 2000

The objective of this study was to examine the physicochemical characteristics of coagulation reaction between loess and red tide organisms (RTO) and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea. The physicochemical characteristics of loess were examined for a particle size distribution, surface characteristics by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrothen closterium and Skeietonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various concentrations of loess, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number. A negative zeta potential of loess increased with increasing pH at $10^(-3)M$ NaCl solution and had -71.3 mV at pH 9.36. Loess had a positive zeta potential of +1,8 mV at pH 1.98, which resulted in a characteristic of material having an amphoteric surface charge. In NaCl and $CaCl_2$, solutions, loess had a decreasing negative zeta potential with increasing $Na^+\;and\;Ca^(+2)$ ion concentration and then didn't result in a charge reversal due to not occurring specific adsorption for $Na^+$ ion while resulted in a charge reversal due to occurring specific adsorption for $Ca^(+2)$ ion. In sea water, loess and RTO showed the similar zeta potential values of -112,1 and -9.2 mV, respectively and sea sand powder showed the highest zeta potential value of -25.7 mV in the clays. EDLs (electrical double-layers) of loess and RTO were extremely compressed due to high concentration of salts included in sea water, As a result, there didn't almost exist EDL repulsive force between loess and RTO approaching each other and then LVDW (London-yan der Waals) attractive force was always larger than EDL repulsive force to easily form a floe. Removal rates of RTO exponentially increased with increasing a loess concentration. The removal rates steeply increased until $800 mg/l$ of loess, and reached $100{\%}$ at 6,400 mg/l of loess. Removal rates of RTO exponentially increased with increasing a G-value. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction. Loess showed the highest RTO removal rates in the clays.