• Title/Summary/Keyword: Physiological effects

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Study on Baled Silage Making of Selected Forage Crop and Pesture Grasses II. Yield performance and nutritieve evaluation of baled silage as affected by stage of growth (주요 사료작물의 곤포 Silage 조제이용에 관한 연구 II. 생육단계별 건물축적형태화 곤포사일리지 조제이용)

  • 김정갑;한민수;김건엽;한정대;강우성;신정남
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.15 no.3
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    • pp.198-206
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    • 1995
  • Baled silage making(BS) of selected forage crops was discussed during 1991-1993, to determine the best cutting time of the plants for BS production, BS yields and silage quality. Seven species of forage crops and pasture grasses(rye, barley, spring oat, Italian ryegrass, orchardgrass, alfalfa and grass-legume pasture mixtures) were harvested at different stage of growth from young plant to physiological maturity, and baled in a self constructed square baling chamber. Each bales, measured 90cm length, 60cm width and 50cm height, were wrapped with 0.05mrn thick polyethylene plastic film, and stored in stack silo. Each bales were weighed between 15-20 kg in dry matter basis. The effects of pre wilting and formic acid addition on the silage quality of young plant materials, which contained high water concentration, was also evaluated during the experiment. Rye plant including of barley and spring oat were evaluated as a good materials for baled silage making. Fodder rye produced high quality BS with a value of silage quality point 84(Flieg's point) when the plant harvested at stage of greatest dry matter accumulation by 12.64 tonha. The best quality BS of barley was obtained at stage of hard dough to yellow stage by 11.9 ton/ha dry matter yield and 81 point silage quality. Italian ryegrass and pasture grasses including of orchardgrass, alfalfa and grass-legume pasture mixtures procuced also high quality bale silage by harvesting at stage of late blooming. However pre witting operation and formic acid addition was required for BS production of grass materials because of high water contents. Water contents of Italian ryegrass and other pasture species ranged 18.9%(Italian) to 20.8%(alfalfa). Silage quality point of Italian BS harvested at late blooing was increased from 72 to 88 by 1/2-one day pre wilting and 0.3% formic acid treatment. Silage quality of young plant materials of rye and other forage crops, barley and spring oat were also improved markedly through the pre wilting treatment and formic acid addition.

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Changes in Starch Synthesis and the Characteristics of Photosynthate Translocation at High Temperature during the Ripening Stage in Barley (보리 등숙기 고온에 따른 전분합성 및 동화산물 전류 특성 변화)

  • Lee, Hyeon-Seok;Hwang, Woon-Ha;Kim, Dae-Wook;Jeong, Jae-Hyeok;Ahn, Seung-Hyeon;Baek, Jeong-seon;Jeong, Han-Yong;Yun, Jong-Tak;Lee, Geon-Hwi;Choi, Kyung-Jin
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.62 no.2
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    • pp.124-133
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    • 2017
  • This experiment was conducted to evaluate the effects of high temperature on the stem, leaf and grain of barley during the ripening period and to provide information for the development of high-temperature cultivation techniques and adaptive varieties. We used an artificial climate control facility, to provide a temperature $3^{\circ}C$ higher than the normal average temperature during the ripening stage. Although the maximum rate of starch synthesis was increased at high temperature by approximately 11%, the starch content was decreased, because the period of starch synthesis ended 4 days earlier. As in the case of starch synthesis, the expression of genes related to starch synthesis was increased at the early ripening stage in the high temperature treatment, however, the duration of expression tended to decrease rapidly. Furthermore, the partitioning rate of assimilation products in the panicle increased to a greater extent in the high temperature treatment than in the control. In contrast, for the stem and leaf, the partitioning rate of assimilation products decreased more rapidly in the high temperature treatment than in the control. On the basis of these results, it can be considered that the translocation rate of assimilation products increased to a greater extent in the high temperature treatment than in the control at the early ripening stage. These results indicate that the decrease in grain weight at high temperature during the ripening stage is attributable to an increase in the speed of starch synthesis at high temperature, but the increase in ripening speed does not compensate for the shortening of the ripening period. Finally to develop varieties and cultivation techniques suited to high temperature, we need to focus on physiological characteristics related to the duration of starch synthesis.

Change in Yield and Quality Characteristics of Rice by Flooding during the Ripening Stage (벼 등숙기 침관수 피해에 따른 수량 및 품질 특성 변화)

  • Lee, Hyeon-Seok;Hwang, Woon-Ha;Jeong, Jae-Hyeok;Ahn, Seung-Hyeon;Baek, Jeong-seon;Jeong, Han-Yong;Park, Hong-kyu;Ku, Bon-il;Yun, Jong-Tak;Lee, Geon-Hwi;Choi, Kyung-Jin
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.62 no.2
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    • pp.87-95
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    • 2017
  • The increase in the frequency of occurrence of abnormal weather could include severe rainfall, which could cause rice submergence during the ripening stage. This experiment was conducted to clarify the effects of submergence during the ripening period on yield and quality of rice. The flooding treatment was conducted at 7 and 14 days after heading. Flooding conditions were created with two conditions, flag leaf exposed and overhead flooding, and each condition was divided into two conditions according to water quality-clear and muddy. Although the yield decrease was more severe at 7 days after heading because of the decrease in the ripening ratio, the head rice ratio was more affected at 14 days after heading because of the increase in the chalky kernel ratio. The maximum quantum yield (Fv/Fm), which indicates the photosynthetic efficiency, did not differ before and after the flooding treatment until flooding continued for 4 days. In addition, stem elongation occurred because of flooding as an avoidance mechanism in japonica rice. This phenomenon was expected to decrease the supply of assimilation products to the spikelet (sink). Overall, it was suggested that additional experiments should be conducted examining the change in the starch synthesis mechanism and transfer of assimilate products resulting from submergence, for development of cultivation techniques corresponding to submergence and breeding of varieties with submergence tolerance characteristics.

Reduction of Mitochondrial Electron Transferase in Rat Bile duct Fibroblast by Clonorchis sinensis Infection (간흡충(Clonorchis sinensis)감염에 의한 흰쥐 담관 섬유모세포 미토콘드리아 전자전달효소의 감소)

  • Min, Byoung-Hoon;Hong, Soon-Hak;Lee, Haeng-Sook;Kim, Soo-Jin;Joo, Kyoung-Hwan
    • Applied Microscopy
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    • v.40 no.2
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    • pp.89-99
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    • 2010
  • Fibroblasts are the most common cells in connective tissue and are responsible for the synthesis of extracellular matrix components. The fibrosis associated with chronic inflammation and injury may contribute to cholangiocarcinoma pathogenesis, particularly through an increase in extracellular matrix components, which participate in the regulation of bile duct differentiation during development. Mitochondria produce ATP through oxidative metabolism to provide energy to the cell under physiological conditions. Also, mitochondrial dysfunction and oxidative stress have been implicated in cellular senescence and aging. Alternations in mitochondrial structure and function are early events of programmed cell death or apoptosis and mitochondria appear to be a central regulator of apoptosis in most somatic cell. Clonorchis sinensis, one of the most important parasite of the human bile duct in East Asia, arouses epithelial hyperplasia and ductal fibrosis. Isolated fibroblast from the bile ducts of rats infected by C. sinensis showed increase of cytoplasmic process. In addition, decrease of cellular proliferation was observed in fibroblasts which was isolated from normal rat bile duct and then cultured in media containing C. sinensis excretory-secretory product. However, the effects of C. sinensis infection on the mitochondrial enzyme distribution is not clearly reported yet. Therefore, we investigated the structural change of C. sinensis infected bile duct and mitochondrial enzyme distribution of the cultured fibroblast isolated from the C. sinensis infected rat bile duct. As a result, C. sinensis infected SD rat bile ducts showed the features of chronic clonorchiasis, such as ductal connective and epithelial tissue dilatation, or ductal fibrosis. In addition, fibroblast in ductal connective tissue was damaged by physical effect of fibrotic tissue and chemical stimulation. Immunohistochemically detected mitochondrial electron transferase (ATPase, COXII, Porin) was decreased in C. sinensis infected rat bile duct and cultured fibroblast from infected rat bile duct. It can be hypothesized that the reason why number of electron transferase decrease in fibroblast isolated from the rat bile duct infected with C. sinensis is because dysfunction of electron transport system is occurred mitochondrial dysfunction, increase of ROS (reactive oxygen species) and apoptosis after chemical damage on the cell caused by C. sinensis infection. Overall, C. sinensis infection induces fibrotic change of ductal connective tissue, mutation of cellular metabolism in fibroblast and mitochondrial dysfunction. Consequently, ductal fibrosis inhibits fibroblast proliferation and decreases mitochondrial electron transferase on fibroblast cytoplasm. It was assumed that the structure of bile duct could not normalized and ductal fibrosis was maintained for a long period of time according to fibroblast metamorphosis and death induced by mitochondrial dysfunction.

Comparative Studies on the Enzymatic Properties of Trypsins from Cat-shark and Mackerel -1. Purifications and Reaction Conditions of the Trypsins- (복상어와 고등어의 Trypsin에 관한 비교 효소학적 연구 -1. Trypsin의 정제와 반응조건-)

  • PYEUN Jae-Hyeung;CHO Deuk-Moon;HEU Min-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.24 no.5
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    • pp.273-288
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    • 1991
  • To elucidate the physiological and biochemical differences between chondrichthyes and osteichthyes, the properties of the specific digestive enzymes in cat-shark, Cephaloscyllium umbratile, and mackerel, Scomber japonicus, were studied. Homogenous trypsin proved through the disc-electrophoresis, SDS-PAG electrophoresis and gel filtration was obtained from the pancreas of cat-shark by $50-70\%$ saturated ammonium sulphate fractionation, DEAE-Sephadex A-50 column chromatography, benzamidine-Sepharose 6B affinity chromatography and Sephadex G-75-120 gel filtration. Two types of trypsins were also obtained from the pyloric caeca of mackerel by $30-70\%$ saturated ammonium sulphate fractionation and the slightly modified procedure from the method adopted in the purification of cat-shark trypsin. The two trypsins, designated trypsin A and B, were proved their homogeneity by disc- and SDS-PAG electrophoresis and gel filtration. The molecular weights of the trypsins were estimated to be 31,700 for cat-shark trypsin, 30,000 for mackerel trypsin A and 29,000 for mackerel trypsin B by SDS-PAG electrophoresis, but those were estimated to be 21,500 for cat-shark trypsin, 23,700 for mackerel trypsin A and 21,500 for mackerel trypsin B by gel filtration. The trypsins exhibited their optimum conditions at pH 9.0 and on temperature ranged from $45^{\circ}C\;to\;50^{\circ}C$ for cat-shark, and at pH 8.0 and a temperature of $50^{\circ}C$ for mackerel trypsin A and B, respectively. The cat-shark trypsin was stable at pH 10.0 and the temperature below $10^{\circ}C$, whereas the mackerel trypsin A and B, were stable in the range over pH 7.0 to pH 9.0 below $10^{\circ}C$ and at pH 8.0 below $35^{\circ}C$, respectively. The mackerel trypsins were severely inhibited by some heavy metal ions such as $Ag^{2+},\;Cu^{2+}\;and\;Hg^{2+}$ compared to cat-shark trypsin. All of the enzymes were also inhibited by antipain, leupeptin, TLCK(tosyllysine chloromethyl ketone) and SBTI(soybean trypsin inhibitor) remarkably. The inhibitory effects of PMSF(phenylmethane sulphonylfluoride), DFP(diisopropyl fluorophosphate) and benzamidine were indicated that these enzymes belong to serine-proteases.

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Extract from Prunus mume Sieb. et Zucc. Fruit Prevents LPS-induced Homotypic Aggregation of Monocytic THP-1 Cells via Suppression of Nitric Oxide Production and NF-κB Activation (매실 추출물의 산화질소 생성과 NF-κB 활성 조절을 통한 LPS유도성 THP-1 세포 동형성 응집의 억제 효과)

  • Lee, Hye-Rim;Park, Youngsook;Kim, Hyun Jeong;Lee, Aram;Choi, Jihea;Pyee, Jaeho;Park, Heonyong;Kim, Jongmin
    • Journal of Life Science
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    • v.25 no.7
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    • pp.801-809
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    • 2015
  • Homotypic cell adhesion (homotypic aggregation) in activated monocytes plays a central role in physiological and pathological processes including inflammatory responses, differentiation and migration. The extract of the Prunus mume Sieb. et Zucc. fruit (Maesil) has potential benefits to human health; such as anti-viral, anti-microbial, and anti-cancer activities. Indeed, Maesil extract may modulate inflammatory responses via interference with homotypic aggregation in monocytes. In the present study, the molecular mechanisms underpinning the therapeutic efficacy of Maesil extract in inflammatory diseases were investigated. It was found that Maesil extract inhibited homotypic aggregation in lipopolysaccharide (LPS)-activated monocytes. This was mediated by reduction of nitric oxide (NO) production, partly via inhibition of inducible nitric oxide synthase (iNOS) expression in LPS-activated THP-1 cells. It was confirmed that NO inhibition is a key mechanism in Maesil induced blockade of monocyte aggregation through identification of reversal of this inhibitory effect by the NO-producing agent S-nitroso-N-acetyl penicillamine (SNAP). In addition, Maesil extract significantly attenuated LPS-induced IκB-α phosphorylation and NF-κB translocation into the nucleus. In conclusion, Maesil extract exerts anti-inflammatory effects via inhibition of homotypic aggregation of LPS-activated monocytes through mechanisms involving the suppression of NO production and NF-κB activity, suggesting Maesil extract as a potential therapeutic candidate for the prevention and treatment of chronic inflammatory diseases.

The Effect of Seasoning on the Intestinal Absorption -Absorption by Passive Transport and the Effect of Red Pepper- (조미료가 창자 운동과 흡수기능에 미치는 영향 -소장의 피동적 흡수에 대한 고추의 영향-)

  • Shin, Dong-Hoon;Kim, Joong-Soo;Koh, Jae-Pyong;Ahn, Seung-Woon
    • The Korean Journal of Physiology
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    • v.7 no.1
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    • pp.23-31
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    • 1973
  • Numerous factors concern with the absorption of substances through the membrane of the gastrointestinal tract. To simplify the experimental condition, present work has been restricted to observe the disappearance rate of substance from the intestinal loop which was made in the jejunum, 70 cm apart from the pylorus of the adult rabbit. The purpose of the study is to clarify the absorption of urea through the jejunal wall is solely attributable to the concentration difference between the luminal fluid and plasma, and to observe the effect of adding red pepper upon the rate of absorption. The rabbits were anesthetized with nembutal, 35mg/kg I.V. Jejunal loop was made by ligating at 2 spots, 70 cm and 80cm apart from the pylorus. After rinsing with normal saline solution through the polyethylene tubing inserted from the end of the loop, 8 ml of test solution was placed through the same tubing. The test solution contained 200 mg% of urea and 150mg% of polyethylene glycol(M.W. 4,000) in normal saline solution. Right after placing the test solution the first specimen was taken through the tubing, and successive samplings were performed at 5, 10, 20, and 30 minutes. Logarithm of the difference of urea concentration between the luminal fluid and plasma was plotted against time elapsed after the onset of the experiment. If straight line is revealed, it would verify the nature of transport mechanism as diffusion, obeying the Fick's principle. The concentration of polyethylene glycol (PEG) was also measured in order to examine the change in the volume. PEG was used as the marker substance because it is not absorbable in the intestinal tract. Consequently the concentration of PEG relates inversely to the volume of the loop. Instantaneous concentration of urea in the loop times the volume will give the amount of urea remaining in the luminal fluid. The change in the amount of any substance is directly relate to the volume of the compartment and differs from the change in the concentration which is independent of the volume. After completion of the experiment without red pepper, it was added in the test solution and was centrifuged after thorough mixing. Supernatant of the mixture was placed in the loop and similar sampling were performed with the same time intervals that of previous run in order to observe the effects of the red pepper on the passive transport of the water soluble small substance, urea. The results obtained were as follows: 1. Logarithm of the concentration difference of urea between the luminal fluid and plasma was diminished exponentially as time elapsed. The decay constant in the experiment without red pepper was 0.0563/min. By adding red pepper in the test solution as much as the concentration rose to 4,000 mg% and 8,000 mg%, the decay constants were lowered to 0.0493/min and to 0.0506/min, respectively. The time interval by which the concentration difference dropped to one half of the initial value was prolonged. Without red pepper the half concentration time was 13.30 minutes, and by adding extract of red pepper, 15.31 minutes and 15.71 minutes were revealed. 2. The profile of the diminishing rate of tile amount of urea was quite different from that of the concentration because of the change in the volume of the loop during the observed period. 3. By adding the extract of red pepper, it slowed down the rate of absorption of urea in the intestinal loop, suggesting an increase in the diffusional barrier. 4. Larger dosage of red pepper brought an increase in the secretion of intestinal fluid with concomitant expansion of the luminal volume, and the retardation of the absorption of urea was noticed. This effect was largely dependent on the sensitivity of the individual animal to the red pepper, extract. The amount of urea remained after 10 minutes interval was 55.5% of the initial amount in the experiment without red pepper. On the other hand it was not consistent after administration of red pepper, showing 50.6% and 66.5% of the initial figures by adding 400 mg and 800 mg of red pepper in the test solution, respectively. It was postulated that symptom of diarrhea often encountered by taking a hot (red pepper) food might be attributable to the increase of secretion and the retardation of absorption in the intestinal tract.

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Cytotoxicity and Multidrug -Resistance Reversing Activity of Extracts from Gamma-Irradiated Coix Zachryma-jobi L. var. ma-yuen Stapf Seed (감마선 조사된 율무종자의 세포독성 및 다제내성 극복활성)

  • Cha, Young-Ju;Lee, Sook-Young
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.5
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    • pp.613-618
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    • 2005
  • This study was carried out to examine the effects of gamma irradiation on the cytotoxicity and multidrug-resistance reversing activity of methanol extracts from Coix lachryma-jobi L. var. me-yuen Stapf seed. The seed was irradiated with doses of 1, 4, 8, 16, 32 and 64 Gy of the gamma radiation, and then extracted by methanol. The extracts were examined for cytotoxicity on the human cancer cell lines, MCF-7 (human breast adenocarcinoma pleural effusion), Calu-6 (human pulmonary carcinoma) and SNU-601 (human gastric carcinoma) cells, and investigated for multidrug-resistance reversing activity using drug sensitive AML-2/WT and multidrug-resistant AML-2/D100 cells. The growth inhibitory activity of irradiated seed extracts on human cancer cell lines was higher than that of the control. In the case of Calu-6 cell line, the effect of cytotoxicity was observed in the extracts of 4, 8 and 16 Gy. $IC_{50}$ value in the MCF-7 cell line was measured in the only 8 Gy extract. And in the SNU-601 cell line as Calu-6, the effect of cytotoxicity was observed in the extracts of 4, 8 and 16 Gy. But the extracts of gamma-irradiated seed over 32 Gy showed little growth inhibitory effect against human cancer cell lines. In this result, 8 Gy extract had significant growth inhibitory in all human cancer cell lines $(Calu-6:\;633\;{\mu}g/mL,\;MCF-7:\;653\;{\mu}g/mL\;and\;SNU-601:\;683\;{\mu}g/mL)$. The extracts of 4, 8 and 16 Gy strongly potentiated vincristine cytotoxicity in AML-2/D100 cells. The reversal fold (RF) of 4, 8 and 16 Gy extracts was 1.7, 1.8 and 1.6, respectively. But their cytotoxicities to both sensitive AML-2/WT and resistant AML-2/D100 cells were in the same order of magnitude. These results indicate that the above samples would contain some principles which have cytotoxicity and multidrug-resistance reversing activity. Irradiation technology can be applied to promote physiological activities of medicinal plant seeds.

Physiochemical and Quality Characteristics of Young Radish (Yulmoo) Kimchi Cultivated by Organic Farming (유기농법에 의해 재배된 열무김치의 품질 및 기능적 특성)

  • Jung, Su-Jin;So, Byung-Ok;Shin, Sang-Wook;Noh, Sun-Ok;Jung, Eun-Soo;Chae, Soo-Wan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.8
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    • pp.1197-1206
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    • 2014
  • This study compared and analyzed the physiochemical and quality characteristics of young radish kimchi made with YR-FNC or YR-GC cultivated by organic farming as well as kimchi made with young radish cultivated by chemical composting/general farming (YR-Control). YR-Control showed higher contents of water and crude protein than YR-FNC and YR-GC kimchi but lower contents of crude ash, dietary fiber, and vitamin C. YR-FNC and YR-GC kimchi also showed higher contents of P and Cu than YR-Control but lower contents of N, K, Ca, Mg, Fe, and Zn. YR-Control fermentation progressed faster than that of YR-FNC or YR-GC after 24 days, and YR-Control more rapidly reached an appropriate pH. On the other hand, YR-FNC and YR-GC kimchi fermentation progressed slow and did not reach a pH level below 5.3. For period of fermentation, YR-Control and YR-FNC kimchi showed no significant difference in reducing sugar content, whereas that of YR-GC kimchi decreased significantly after 24 days of fermentation (P<0.002). YR-FNC and YR-GC kimchi showed 1.5~3 times higher total polyphenol and flavonoid contents than YR-Control at the beginning of fermentation, whereas YR-Control and YR-FNC kimchi showed a significant increase in total polyphenol and flavonoid contents during the fermentation period. By day 7 of fermentation, YR-FNC kimchi showed higher contents of lactic acid bacteria and total microbes than YR-Control. In the sensory evaluation, YR-FNC and YR-GC kimchi showed higher preference values than YR-Control. Therefore, kimchi made from young radish cultivated by organic farming has a longer freshness period than control kimchi and is characterized by excellent sensory quality, increased physiological contents, and improved beneficial health effects.

Protective Effect of Saengshik Supplementation on Lead Induced Toxicity in Rats (생식의 섭취가 납중독 흰쥐의 피해 경감에 미치는 영향에 관한 연구)

  • Oh, Young-Joo;Kim, Jae-Min;Song, Si-Wan;Ha, Hyo-Cheol;Kim, Hyun-Su
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.7
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    • pp.959-967
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    • 2005
  • Lead is a ubiquitous environmental and industrial pollutant that causes a major health concerns. It is known to induce a broad range of physiological, biochemical, and behavioral dysfunctions in laboratory and humans, including hematopoietic system, kidneys, liver, and reproductive system. This study was conducted to investigate the effect of Saengshik supplementation on the lead-induced toxicity in rats. Five week old male Sprague­Dawley rats were randomly assigned to five groups for six weeks as followings: control group (CT), lead acetate treated group (PT), and lead acetate groups administered with three different dosages of Saengshik $(SI2.5-12.5\%,\;S25-25\%,\;and\;S50-50\%).$ Lead acetate (12 mg/rat) was intragastrically administered daily for 6 weeks. The results were summarized as follows; Weight gain and food efficiency ratio were significantly lower (p<0.05) in lead administered group compared with those of the control group. Also, significant lead-induced alteration in blood hemoglobin (HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and reticulocyte distribution width (RDW) were observed. In the liver of lead-exposed animals, there was an increase in the lipid peroxidation (MDA) and the level of glutathione (GSH), but superoxiede dismutase (SOD) activity did not change. Lead-exposed animals with $25\%\;and\;50\%$ Saengshik supplementation showed marked improvements in the values of MCH, MCV, and RDW. Also, the level of HCT was significantly increased by $50\%$ Saengshik supplementation. The levels of liver MDA in $12.5\%\;and\;50\%$ Saengshik administered groups and GSH level in $50\%$ Saengshik administered group were significantly decreased compared to the lead administered group. Also, hepatic SOD activity tended to increase in the presence of Saengshik supplementation. Furthermore, the accumulation of lead in liver and kidney was reduced by presence of Saneghshik supplementation. Liver lead concentration was significantly reduced by both $25\%\;and\;50\%$ Saengshik supplementations and kidney lead concentration was significantly reduced by the $25\%$ Saengshik supplementation. These results show that Saengshik may have a protective effect against lead intoxication but the mechanism of their effects remains unclear.