• The Korean Journal of Physiology
• /
• v.23 no.2
• /
• pp.253-261
• /
• 1989

Responses of atrial natriuretic peptide (ANP), aldosterone and renin release to acute volume expansion were compared in normotensive Wistar and spontaneously hypertensive rat (SHR) fed low or high-sodium diet (2 or 25 mmol Na/100 g diet). Experimental diets were fed for 6 weeks from 7-week-old and the growth rate was similar in all groups. In the morning of the experiment, catheters were inserted under ether anesthesia in femoral artery for pressure recording and blood collection, femoral vein for saline infusion, and bladder for urine collection. Then, the rats were placed in restraining cages. When the rats were recovered from anesthesia and the arterial pressure became stabilized, control urine and blood samples were collected. Then, 0.9% saline was infused for 30 min for volume expansion (3% BW). Arterial pressure was significantly higher in the high-sodium SHR but there was no difference between the two groups of Wistar rats. Control plasma levels of Na, K, ANP, renin activity, and hematocrit were not different among the 4 groups. However, plasma aldosterone level was significantly higher in the low-sodium groups. Wistar low-sodium rats showed approximately two times higher plasma aldosterone level than the SHR counterpart. Volume expansion produced a marked increase in plasma ANP level, especially in the high-sodium groups. The low-sodium groups of both strains showed approximately two-fold increase in plasma ANP level. Following a volume expansion plasma aldosterone level and renin activity decreased in all groups. There was a significant logarithmic positive correlation between plasma renin activity and aldosterone concentration. The low-sodium rats produced a greater increase in aldosterone release by small increase in plasma renin than did the high-sodium rats. The low- and high-sodium rats produced a similar degree of diuresis and natriuresis after volume expansion. However, SHR produced a greater natriuresis than did the Wistar rats. The above results indicate that regulatory mechanisms of ANP, aldosterone and renin release are different between the normotensive and hypertensive rats, and between the low- and high-sodium groups.

• Korean journal of food and cookery science
• /
• v.1 no.1
• /
• pp.74-81
• /
• 1985

For this research, the Atka-fisher which are used commonly in many homes for baking and broilling were broiled by an iron baking method, a pan baking method, a grill baking method and a microwave baking method respectively after 20 hours salting with 3% salt concentration of fish muscle weight. This thesis has an intention of appreciating the tastes according to each baking method through a sensory test, of examining the corelation between the change of texture measured by Rheometer and a sensory test and of comparing the changes of chemical component of the fish. The results were as follow: 1. The appearance of the broiled Atka-fish maintained a good appearance by the iron baking method and the grill baking method. In the color, the iron baking method and the grill baking method by direct :fire resulted a good score too. In the flavor, there was a significant difference between the grill baking method and the microwave baking method while there was no difference between the iron baking method and the pan baking method. The result of tenderness showed that the pan baking method has the highest score. Difference between the iron baking method and the pan baking was not significant. There was no difference in tenderness between the grill baking method and the microwave baking method. The iron baking method showed-the highest score in juciness and the microwave baking method stowed the highest score in acceptability however the differences were not significant. 2. As a result of the measurement of the texture by Rheometer, the iron baking method and the grill baking method showed higher score than other methods in hardness and chewiness. In springiness and cohesiveness, there was no significant difference among methods. As a result of the measurement of the texture by Rheometer, the corelation with a sensory test was considered to be low. 3. After broil, the cooking retention was the highest in the pan baking method and the moisture content was the highest in microwave baking method. Nitrogen content was the highest in the iron baking method. Fat content was the highest in the iron baking method, followed by the grill baking method, the pan baking method, and the microwave baking method. Free amino acid content was the highest in the iron baking method, followed by the grill baking method, the pan baking method and the micro-wave baking method.

• KSBB Journal
• /
• v.14 no.5
• /
• pp.585-592
• /
• 1999

This study was aimed to enhance the Fe(II) oxidation rate using immobilized cells of Thiobacillus ferroxidans. For this purpose, a medium for the minimization of jarosite formation was developed first. Secondly, cell immobilization in celite beads was carried out. And then, repeated-batch and continuous operatons of Fe(II) oxidation by using immobilization cells were performed. In a series of flask cultures, three types of media were tested: media with a much lower salt concentration than that of the 9K medium; media which contained different nitrogen sources from that of the 9K medium, that is $(NH_4)_2HPO_4$, $NH_4Cl and HNO$_3$; media which contained $(NH_4)_2HPO_4$ as nitrogen and phosphate source, but without $K_2HPO_4$ as nitrogen and phosphate source in the 9K medium. As a result, the M16 medium which contained 3 g/L of $(NH_4)_2HPO_4$ as nitrogen and phosphate source was found to be the optimal one. It sustained good cell growth allowing no jarosite formation. In the repeated-batch operations, the rate of Fe(II) oxidation gradually increased to reach a maximum value as the batch was repeated. As a result of repeated-batch operations. a maximum Fe(II) oxidation rate was 2.33 g/L . h. In the continuous operations, the iron oxidation rate could be increased to 2.14 g/L .h at a dilution rate of 0.25 $h^{-1}$ which is greater than the maximum specific growth rate (0.12 $h^{-1}$) of the bacteria.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.11
• /
• pp.1458-1464
• /
• 2007

This study was conducted to develope a new type of ready-to-eat smoked Sebastes schlegeli product with high acceptability and extended shelf-life. A Sebastes schlegeli was salted at 4% salt concentration for 6 hr at $4^{\circ}C$. The cold smoking conditions for the salted Sebastes schlegeli consisted of drying for 2 hr at $22{\sim}24^{\circ}C$ followed by smoking for 2 hr at $22{\sim}24^{\circ}C$. The warm smoking conditions for the salted Sebastes schlegeli consisted of drying for 2 hr at $22{\sim}24^{\circ}C$, smoking for 2 hr at $22{\sim}24^{\circ}C$, and smoking again for 30 min at $47{\sim}50^{\circ}C$. The rancidity of the smoked Sebastes schlegeli did not change after 1 year storage at $-20^{\circ}C$ by monitoring the iodine value, peroxide value, and acid value. The number of viable cells in the cold and warm smoked samples were counted as $7.4{\times}10^5$ and $6.2{times}10^5$ CFU/g, respectively. Viable cells were not detected after 1 year of storage at $-20^{\circ}C$. The sensory evaluations of the processed Sebastes schlegeli showed that elastic texture increased with smoking as compared to with salting. There were no significant differences between cold and warm smoking in terms of sweetness, elastic texture, color, and smoke flavor. However, for overall acceptability, preference were in the oder of cold smoked, warm smoked, and salted.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.7
• /
• pp.885-891
• /
• 2009

To examine stability of a violet red pigment in a Salicornia herbacea L., several tests for pH, sugar, organic acid, ascorbic acid, amino acid, salt and temperature effect were carried out. A violet red pigment in Salicornia herbacea L. was the most stable in the range of pH 4 to 6. Each of the violet red pigments in Salicornia herbacea L. added with different amounts of sugar showed higher retention rate according to storage time than those of the control group. After 10 days of storage, especially the retention rate of the experimentals with 0.5 M sucrose was higher than the controls by about 11.1% while fructose, maltose, glucose and galactose were less higher in order. Also, adding organic acid reduced retention rate of the experimentals over the controls irrespective of sort and concentration of organic acid; also, the retention rate of the experiment with 0.5 M organic acid, the highest amount of all, reduced radically to 13.1 to 15.9% after 10 days storage. The retention rate of the experimentals added 1,000 ppm ascorbic acid and thio urea respectively after 10 days was 48.4%, which is higher than the controls by around 23.1%. As to amino acid, treatment on the pigment with aspartic acid 50 mM marked the highest retention rate of 41.5% and treatment with 2.0 M NaCl showed 31.6% retention rate, which was higher than the controls. While low temperature like $5^{\circ}C$ and $25^{\circ}C$ kept the stability of the pigment in storage, as temperature increased the stability of the pigment dropped rapidly.

• Journal of Life Science
• /
• v.19 no.2
• /
• pp.277-283
• /
• 2009

Biogenic amines are generally formed through the decarboxylation of specific free amino acids by exogenous decarboxylases released by microbial species associated with the fish products and fermented feeds. This study was conducted to investigate the properties of e tuna waste regarding the control of degradation of biogenic amines (histamine, tyramine, tryptamine, putrescine, and cadaverine) that might be related with the anti-nutritional factor of the tuna waste that is used for manufacturing domestic fish meal. The values of pH and the salt content were 6.51, 3.35% in tuna waste and 5.58 and 5.83% in tuna fish meal, respectively. The strains and dominant bacteria tested in the tuna waste sample were 9.20, 9.29, 5.67, 7.82 and 7.58 log CFU/g of total bacteria, aerobic plate count (APC), total coliform (TC), Lactobacillus spp. and Bacillus spp., respectively. The main histamine forming-bacteria (HFB) in tuna waste were detected by silica gel thin-layer chromatography (TLC) and 7 histamine-forming bacterial species were isolated among microbes grown in selective medium. The histamine concentration was determined by detection of fluorescence of ο-phthaldialdehyde (OPA) derivatives using HPLC and the date were used to reconfirm the identities of the amine-producing bacteria. The 15 histamine- forming bacteria strains grown in trypicase soy broth (TSB) supplemented with 1% L-histidine (TSBH) were identified as Lactococcus(L.) lactis subsp. lactis, Klebsiella pneummonlae, L. garvieae 36, Vibrio olivaceus, Hafnia alvei and L. garvieae which were main dominant amine - producing strains, and Morganella morganii identified by 16S ribosomal RNA (rRNA) sequencing with PCR amplification. A Phylogenetic tree generated from the 16S rRNA sequencing data showed different phyletic lines that could be readily classified as biogenic amine forming gram-positive and negative bacteria.

• Korean Journal of Food Science and Technology
• /
• v.6 no.2
• /
• pp.116-123
• /
• 1974

1) In Seoul, it was known that the season for preparing Kimchies (fermented vegetables) for the winter was from the middle of November to early in December, in which the preparing rates of Kimchies in the middle of November, the end of November and early in December were 32.7%, 41.3% and 12.5%, respectively. The time that the largest quantity of them was prepared was about the end of November. 2) The average cost of Kimchies prepared for the winter for a family of four, five, six and seven was $10,000{\sim}15,000$ Won, $15,100{\sim}20,000$ Won, $10,100{\sim}20,000$ Won and $10,100{\sim}20,000$ Won, respectively, and the cost did not increase in proportion to members of a family. In case of the family of $6{\sim}7$, the cost for Kimchies showed a wide range compared with those for the family of $4{\sim}5$ 3) The main raw materials of kimchi for one person for the winter required $12{\sim}20$ heads of Chinese cabbages, $14{\sim}20$ roots of radishes, $4{\sim}7$ cloves of garlics and $300{\sim}500g$ of powdered red pepper. 4) The residents living in Seoul had prepared the several kinds of the pickles for the winter as follows; (1) Chinese cabbage Kimchi (98.9%), (2) Whole Chinese cabbage Kimchi (74.7%), (3) Kkakdugi (68.6%), (4) Dongchimi (66.4%) and (5) Chong-kak Kimchi (63.3%). It has, therefore. been considered that the five kinds of Kimchies mentioned above may be industrialized. 5) Uniqueness of the raw materials used for the most popular Chinese cabbage Kimchi was to use leeks, garlics, red peppers and gingers as spices, and it was also known that proper amounts of salted shrimp pickles and oysters was mixed to the Kimchies. Therefore, it had been considered that the characteristics of Chinese cabbage Kimchies for the winter had the hot taste with freshness. 6) For keeping the Kimchies during the winter about the half of the pickle jars was buried in the ground, and another half of them were wrapped in the straw bags or styropol and they were placed on the ground or kept in the basement, 7) In most case (80.9%), the salt concentration of pickling was adjusted by one's experiences, and only 19% of them was measured with the instruments. 8) Most of remaining kimchies were usually used for other cooks, but some of them were thrown away. 9) The ratio of the people who had ever bought the market Kimchies for their own edibility was 17.8% and most of them got it only in the spring and summer season. 10) About 18% of the residents living in the general houses in Seoul had ever bought the market Kimchies. It was also known that about 48% of the residents living in the general houses and about 79% of the residents living in the apartments wanted to purchase the market Kimchies if the production of the delicious Kimchies were industrialized. The season that the people wanted to get the market Kimchies was a little different each other among the residents. About 13.4% of the residents living in the general houses wanted to purchase the Kimchies during the summer, and 11.9% of them wanted to get it throughout the year. On the other hand, in case of the apartments, 25.2% of the residents wanted to get it during the summer and 24.4% of them wanted it throughout the year (4 seasons) and 19.9% of them wanted it during two seasons. The data mentioned above have shown that many residents hope strongly an industrial production of the Kimchies. It is also true that many residents living in both the general houses and apartments want to get the market kimchies throughout the year, and particulary during the summer season that most foods are very apt to be spoiled.

• Korean Journal of Soil Science and Fertilizer
• /
• v.43 no.5
• /
• pp.578-583
• /
• 2010

Acid rain and its problem to environment such as acid precipitation and environmental problems related to the air pollution in East Asia has been emerging. To evaluate the acidity and chemical characteristics of rainwater precipitated in western Korea, Suwon and Taean, its pH and ion concentrations were investigated during farming season (April to November) in 2009. Also, ion composition and cation-affected neutralization were determined to evaluate the contribution of cations on the acidity of rainwater. Ion and electrical conductivity between the measured and the estimated showed high correlation. The $Na^+$ in rainwater was the main cation followed by ${NH_4}^+>Ca^{2+}>H^+>Mg^{2+}>K^+$. Sum of $Na^+$ and ${NH_4}^+$ contents was over 65% of total cations contents. In the case of anions, the concentration was in order of ${SO_4}^{2-}>{NO_3}^->Cl^-$. The ${SO_4}^{2-}$ among anions in rainwater composed about 61%, which showed on average 130.2 ${\mu}eq\;L^{-1}$ and 121.3 ${\mu}eq\;L^{-1}$ during monitoring at Suwon and Taean, respectively. Also, 89.6 and 88.6% of soluble sulfate in rainwater at Suwon and Taean area was NSS-${SO_4}^{2-}$ (Non-Sea Salt sulfate). Especially, ${NH_4}^+$ and $Ca^{2+}$ contributed greatly in neutralizing the acid rain in dry season. Total nitrogen content flowed into soil from rain was around 1~2 kg $ha^{-1}$ in each month, but in July at Suwon, it reached 6 kg $ha^{-1}$ due to heavy rain (over 7.3 mm).

• Korean Journal of Soil Science and Fertilizer
• /
• v.7 no.4
• /
• pp.227-234
• /
• 1974

A survey on the vinyl house soils was conducted to investigate the salt accumulation status and it's effects on the deterioration of soil aggregates. The survey was made for the vinyl house soils in Suwon, Yesan, and Kimhae areas where vegetables are extensively grown under a vinyl house. Physical and chemical properties of the soils at the inside and outside of the vinyl house were compared to continuous vegetable cropping. Electrical conductivity of the soil solution (Y) in vinyl house was closely related to the number of cropping years (X), and the relations are given by the following regression equations: $Y=0.54X{\times}1.44$ ($r=0.580^*$) for loamy textured soils and $Y=0.58X{\times}2.61$ ($r=0.524^*$) for clayey textured soils. Electrical conductivity of the soils, where vegetable cropping in winter and rice in summer were rotated, was lower than that given by the regression equations. Analyses for extractable cations, the concentration of calcium, sodium and potassium was high in the inside vinyl house soils compared to the outside. Soil aggregates larger than 1mm in diameter were greatly deteriorated, while the content of the soil aggregates smaller than 0.5mm in diameter remained unchanged. Aggregate stability of the soil was negatively correlated to the accumulation rate of extractable sodium ($r=-0.681^{**}$), potassium ($r=-0.528^*$) and the amount of daily irrigated water (r=-0.477), while positively correlated to the content of organic matter ($r=-0.692^{**}$) and calcium (r=0.391).

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.42 no.1
• /
• pp.75-85
• /
• 2016

Pectin, a naturally occurring polysaccharide, has in recent years attracted considerable attention. Its benefits are increasingly appreciated by scientists and consumers due to its safety and usefulness. The chemistry and gel-forming characteristics of pectin have enabled to be used in pharmaceutical industry, health promotion and treatment. Yet, it has been rarely used in cosmetics because of its incompatibility with many cosmetic ingredients, including alcohols, and unstable viscosity of pectin gels under various pH and salt conditions. However, low-molecular-weight pectin oligomers have excellent biological activities, and depolymerization of pectin to produce cosmetic ingredients would be very useful. In this study, we attempted the development of cosmetic ingredients using pectin with an excellent effect on human skin. We developed a bio-conversion process that uses enzymatic hydrolysis to produce pectin hydrolysates containing mainly low-molecular-weight pectin oligomers. Gel permeation chromatography was used to determined the ratio of hydrolysis. The molecular weight of the pectin hydrolysates obtained varied between 200 and 2,700 Da. The two newly developed low-molecular-weight pectin hydrolysates, LMPH A and B, had higher anti-oxidative activities than pectin or D-galacturonic. Exposure to UVB radiation induces apoptotic cell death in epidermal cells. Annexin V binding and propidium iodide uptake were measured by flow cytometry to evaluate UVB-induced cell death in HaCaT cells. Both LMPH A and B reduced UVB-induced cell death and increased cell proliferation by 22% and 30% at 0.5% concentration respectively, while pectin had no significant activity. In conclusion, this study suggests that the newly developed low-molecular-weight pectin hydrolysates can be used as safe and biologically active cosmetic ingredients.