• 제목/요약/키워드: water content (W$W_{0}$)

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Utilization of Ascidian, Halocynthia roretzi -2. Lipids of Ascidian with seasonal and regional variation- (우렁쉥이 이용에 관한 연구 -2. 계절 및 서식지에 따른 우렁쉥이의 지질성분-)

  • LEE Kang-Ho;PARK Chun-Soo;HONG Byeong-Il;JUNG Woo-Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.2
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    • pp.141-149
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    • 1993
  • The seasonal variation of lipid content was mostly attributed to diet, water temperature and period of reproduction etc. The lipid mainly consisted of neutral lipid and phospholipid. Nonpolar lipid content was higher in between late spring and summer, while polar lipid content lower during the period. The composition of neutral, glyco, and phospholipid of the total lipid: in average was 53.88, 10.09 and $36.03\%$, respectively. The neutral lipids were composed of triglycride($51.88\%$) and free sterol($23.21\%$) as major component and a little quantity of diglycerides, monoglycerides, esterified sterols and hydrocarbon, free fatty acid were also identified. The phospholipids of each fraction were mainly occupied by phosphatidyl choline($55.5\%$), followed by phosphatidyl ethanolamine($27.8\%$), phosphatidyl inositol($8.65\%$) and phosphatidyl serine($4.85\%$). The major fatty acids of the total lipid in ascidian were $C_{20:5},\;C_{22:6},\;C_{16:6}\;and\;C_{18:1}$, respectively. The fatty acid composition of phospholipid and neutral lipid showed a similar tendency to that of the total lipid. The major fatty acids in the fraction of glycolipid, however, appeared $C_{16:0},\;C_{20:1},\;C_{18:0}\;and\;C_{18:1}$ in order.

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Effects of Herbal Recipe Herb Mix Gold® on the Performance of Laying Birds (개량 한방제제(Herb Mix Gold®) 첨가가 산란계 생산성에 미치는 영향)

  • Lee, W.S.;Paik, I.K.
    • Korean Journal of Poultry Science
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    • v.34 no.1
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    • pp.37-42
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    • 2007
  • This study was conducted to investigate the effects of graded levels of a herbal recipe(Herb Mix $Gold^{(R)}$, Herb BIO Co.) supplemented to a commercial layer diet. The Herb Mix $Gold^{(R)}$ is an improved recipe of Herb $Mix^{(R)}$, fortified with Angelica gigas, Discorea japonica and Ligusticum jeholense. A total of 720 layers (Hy-Line Brown) of 45 wks old were assigned to one of six treatments; control, 0.2% Herb $Mix^{(R)}$, 0.1%, 0.2%, and 0.3% Herb Mix $Gold^{(R)}$, and 6 ppm Avilamycin. Each treatment had 6 replicates of 20 birds each housed in 2 birds cages. Birds were fed diets and water ad libitum for 5 weeks. Hen-day egg production was significantly (P<0.05) different among treatments. Herb Mix $Gold^{(R)}$ 0.2% treatment showed the highest egg production followed by Herb Mix $Gold^{(R)}$ 0.3%, Herb $Mix^{(R)}$ 0.2%, Herb Mix $Gold^{(R)}$ 0.1%, Avilamycin 6 ppm and the control. Hen-housed egg production, egg weight, soft and broken egg ration, feed intake, feed conversion ratio, shell strength, shell thickness, shell color index, Haugh unit and yolk color index were not significantly different among treatments. Nor was cfu of Cl. perfringens and E. coli and Lactobacilli in the small intestinal content significantly different among treatments. The number of white and red blood cells, hemoglobin, heterophil, lymphocyte, thus heterophil to lymphocyte ratio were not significantly modified. It was concluded that Herb Mix $Gold^{(R)}$ at the level of 0.2% in the layer diet improves laying performance.

Soil Physical Properties of Arable Land by Land Use Across the Country (토지이용별 전국 농경지 토양물리적 특성)

  • Cho, H.R.;Zhang, Y.S.;Han, K.H.;Cho, H.J.;Ryu, J.H.;Jung, K.Y.;Cho, K.R.;Ro, A.S.;Lim, S.J.;Choi, S.C.;Lee, J.I.;Lee, W.K.;Ahn, B.K.;Kim, B.H.;Kim, C.Y.;Park, J.H.;Hyun, S.H.
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.3
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    • pp.344-352
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    • 2012
  • Soil physical properties determine soil quality in aspect of root growth, infiltration, water and nutrient holding capacity. Although the monitoring of soil physical properties is important for sustainable agricultural production, there were few studies. This study was conducted to investigate the condition of soil physical properties of arable land according to land use across the country. The work was investigated on plastic film house soils, upland soils, orchard soils, and paddy soils from 2008 to 2011, including depth of topsoil, bulk density, hardness, soil texture, and organic matter. The average physical properties were following; In plastic film house soils, the depth of topsoil was 16.2 cm. For the topsoils, hardness was 9.0 mm, bulk density was 1.09 Mg $m^{-3}$, and organic matter content was 29.0 g $kg^{-1}$. For the subsoils, hardness was 19.8 mm, bulk density was 1.32 Mg $m^{-3}$, and organic matter content was 29.5 g $kg^{-1}$; In upland soils, depth of topsoil was 13.3 cm. For the topsoils, hardness was 11.3 mm, bulk density was 1.33 Mg $m^{-3}$, and organic matter content was 20.6 g $kg^{-1}$. For the subsoils, hardness was 18.8 mm, bulk density was 1.52 Mg $m^{-3}$, and organic matter content was 13.0 g $kg^{-1}$. Classified by the types of crop, soil physical properties were high value in a group of deep-rooted vegetables and a group of short-rooted vegetables soil, but low value in a group of leafy vegetables soil; In orchard soils, the depth of topsoil was 15.4 cm. For the topsoils, hardness was 16.1 mm, bulk density was 1.25 Mg $m^{-3}$, and organic matter content was 28.5 g $kg^{-1}$. For the subsoils, hardness was 19.8 mm, bulk density was 1.41 Mg $m^{-3}$, and organic matter content was 15.9 g $kg^{-1}$; In paddy soils, the depth of topsoil was 17.5 cm. For the topsoils, hardness was 15.3 mm, bulk density was 1.22 Mg $m^{-3}$, and organic matter content was 23.5 g $kg^{-1}$. For the subsoils, hardness was 20.3 mm, bulk density was 1.47 Mg $m^{-3}$, and organic matter content was 17.5 g $kg^{-1}$. The average of bulk density was plastic film house soils < paddy soils < orchard soils < upland soils in order, according to land use. The bulk density value of topsoils is mainly distributed in 1.0~1.25 Mg $m^{-3}$. The bulk density value of subsoils is mostly distributed in more than 1.50, 1.35~1.50, and 1.0~1.50 Mg $m^{-3}$ for upland and paddy soils, orchard soils, and plastic film house soils, respectively. Classified by soil textural family, there was lower bulk density in clayey soil, and higher bulk density in fine silty and sandy soil. Soil physical properties and distribution of topography were different classified by the types of land use and growing crops. Therefore, we need to consider the types of land use and crop for appropriate soil management.

Quality properties of samkwang and palbangmi treated with atmospheric-pressure plasma by storage (대기압 플라즈마에 의한 삼광 및 팔방미의 저장에 따른 품질 특성)

  • Kim, Hyun-Joo;Woo, Koan Sik;Yong, Hae In;Jo, Cheorun;Lee, Seuk Ki;Lee, Byong Won;Lee, Yu-Young;Oh, Sea-Kwan;Lee, Byoungkyu
    • Korean Journal of Food Science and Technology
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    • v.50 no.2
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    • pp.165-171
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    • 2018
  • Atmospheric-pressure plasma (APP) was applied to determine quality characteristics of brown rice (BR) and white rice (WR) of Samkwang and Palbangmi. APP (250 W, 15 kHz, ambient air) was generated and dielectric barrier discharge was applied for 0, 10, and 20 min for 2 weeks at 4 and $25^{\circ}C$. The growth of total aerobic bacteria and mold increased depending on the storage. Water content of BR and WR decreased by storage temperature and periods. No viable counts were detected for molds by APP-treated 20 min at $4^{\circ}C$. Changes in protein and damaged starch contents in plasma were not observed. Amylose contents were not changed, but WR (Palbangmi) showed a tendency to increase. The results show that APP improved the microbial quality of BR and WR of Samkwang and Palbangmi, although further studies should be conducted to determine change in quality by APP.

Effects of Kimchi Solvent Fractions on Accumulation of Lipids in Heart, Kidney and Lung of Rabbit Fed High Cholesterol Diet (김치 용매획분이 고 콜레스테롤 식이를 섭취한 토끼의 심장, 신장 및 폐의 지질 축적에 미치는 영향)

  • 송영옥;전혜년;권명자
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.5
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    • pp.814-818
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    • 2002
  • The effects of dichloromethane (CH$_2$C1$_2$), ethylacetate (EtOAc) or water ($H_2O$) fraction of Korean cabbage kimhi on accumulation of lipids in the heart, kidney and lung of rabbit fed 1% cholesterol diet for 16 weeks were studied. The amount of kimhi fraction added to the 100 g of diet was 8.3 mg of CHaC12.5.6 W of EtOAc, and 221.9 mg of $H_2O$, which are equivalent to 5% of freeze-dried kimhi added to the diet. Each group had 6 rabbits and rabbit was housed individually. Cholesterol and triglyceride concentrations of three organs were noticeably decreased due to these solvent fractions of kimhi but for phospholipid and total lipids, only CH$_2$C1$_2$ fraction group showed decreasing effects. In the heart, compared to the control, cholesterol concentrations for CE$_2$C1$_2$, EtOAc, and H2O fraction group were decreased by 42 (P<0.05),21 (P<0.05), and 8%, respectively, and triglyceride for these groups were decreased by 29 (p<0.05),4, and 11%, respectively. In kidney, cholesterol concentration for CH$_2$C1$_2$, EtOAc, and H2O fraction group were decreased by 23, 12, and 11%, respectively (p<0.05) and triglyceride concentration for CH$_2$Cl$_2$ and H2O fraction groups were significantly decreased by 51 and 21%, respectively (p<0.05). In lung, cholesterol concentrations for CItCIB, EtOAc, and H2O fraction groups were decreased by 37,20, and 22%, respectively (p<0.05) and triglyceride concentration of these groups were significantly decreased by 39, 28, and 28%, respectively (p<0.05). And phospholipid and total lipid of CH$_2$CI$_2$ fraction group were significantly decreased by 33 and 34% respectively (p<0.05). Among three organs the cholesterol content of lung was the highest followed kidney and heart. For triglyceride, heart, kidney and lung is in the order of showing the highest concentration. The phospholipid concentration was not significantly different among three organs. According to these results, we may conclude that CH$_2$C1$_2$, fraction of kimhi might have the most active component, which decreases cholesterol, triglyceride, phospholipid and total lipids concentrations in heart, kidney, and lung of rabbit fed high cholesterol diet.

Effects of Feeding Period on Carcass and Objective Meat Quality in Crossbred Longissimus Muscle (교잡종 돼지에서 비육기간에 따른 돈육 등심의 이화학적 특성 변화)

  • Jin, S.K.;Kim, I.S.;Hur, S.J.;Hah, K.H.;Kim, B.W.
    • Journal of Animal Science and Technology
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    • v.46 no.5
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    • pp.811-820
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    • 2004
  • Objectives of this study was to determine the comparisons of physico-chemical characteristics in crossbred pigs(Korean native breed ${\times}$ Landrace breed) by feeding periods. A total of 150 pigs were sampled from commercial farm, and assigned into three treatedrnents. Feeding peirods of Tl, T2 and T3 were below 200 days, 220-220 days, over 220 days, respectively. Live weight, carcass weight and backfat thickness were significantly(P<0.05) increased with feeding period increased, and final grade score have significantly(P<0.05) lower when feeding period was increased. pH and water content were significantly(P<0.05) lower when feeding period was increased(over 220days). However, intramuscular fat have no significantly different among the treatments. $L^* and b^* were significantly(P<0.05) lower and a^*$ was significantly higher(P<0.05) when feeding period increased. Cooking loss was higher in the order of Tl > T3 > T2. Shear force values was significantly(P<0.05) decreased by feed period increase. In fatty acids, myristic acid, palmitic acid, stearic acid and saturated fatty acid(SFA) in T2 were significantly(P<0.05) lower in T2, whereas linolenic acid, unsaturated fatty acid(UFA), essential fatty acid(EFA), UFA/SFA and EFA/SFA were significantly higher in T2 compared with other treatment. However palmitoleic acid and arachidonic acid were no significantly different with feeding periods. As a result of this study, crossbred pigs was increased live weight and carcass weight with feeding periods. and improved meat color and tenderness with feeding periods. However, final grade score was decreased with feeding periods

Quality Characteristics of Fermented Pork with Korean Traditional Seasonings (한국 전통 양념을 이용한 발효 돼지고기의 품질 특성)

  • Jin, S.K.;Kim, C.W.;Lee, S.W.;Song, Y.M.;Kim, I.S.;Park, S.K.;Hah, K.H.;Bae, D.S.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.217-226
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    • 2004
  • This study was canied out to evaluate the quality characteristics of the fermented pork with Korean traditional seasonings. The samples, outside muscle of pork ham were cut to cube(7 ${\times}$ 12 ${\times}$ 2cm) and five Korean traditional seasonings such as garlic paste(TI), pickled Kimchi(T2), pickled Kimchi juice(T3), soybean paste(T4), red pepper paste(T5) were seasoned by the proportions of meat to seasonings(1 : 1). The seasoned samples were fennented at - 1 ${\pm}$ 1$^{\circ}C$ for 20 days. According to proximate composition analysis, all pork samples contained protein 20 ${\sim}$ 22%, fat 3 ${\sim}$ 5%, moisture 64 ${\sim}$ 70% and ash 1.8 ${\sim}$ 2.0%. However, T5 had high crude fat level and relatively low moisture content. The highest pH among treatments was shown in TI whereas T3 showed the lowest. Water holding capacity(WHC) of T4 and T5 were higher, while those values were lower in T3 compared with other treatment. Shear force value was the highest in T5, while it was the lowest in T4. TBARS value of T3 was the highest, while that was the lowest in T4. Moreover the highest VBN value was observed in T4 due to fermentation of soy protein. However, the lowest VBN value shown in Tl indicated the inhibition of protein degradation by the garlic. The highest saccarinity was shown in T5 but it was the lowest of in T3. Salinity was shown to be high in T2 and low in T5. $L^*$ values of T4 was higher both at the surface and inner side of samples than the others but T5 showed the lowest value. T2 showed the highest $a^*$ value but T4 and T5 showed the lowest. In the result of sensory evaluation for cooked meat, T5 had the highest score in all item including overall acceptability, while T4 had the lowest score. Unsaturated fatty acid(UFA) ratio of T5 and n were 72.16 and 69.93 respectively, and the ratio of UFA/Saturated fatty acid(SFA) were higher in the order of T5 >T4> T3 >Tl >T2. Overall quality characteristics were higher in the order of T5 >T2 >Tl >T4 >T3.

Herbicidal Phytotoxicity under Adverse Environments and Countermeasures (불량환경하(不良環境下)에서의 제초제(除草劑) 약해(藥害)와 경감기술(輕減技術))

  • Kwon, Y.W.;Hwang, H.S.;Kang, B.H.
    • Korean Journal of Weed Science
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    • v.13 no.4
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    • pp.210-233
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    • 1993
  • The herbicide has become indispensable as much as nitrogen fertilizer in Korean agriculture from 1970 onwards. It is estimated that in 1991 more than 40 herbicides were registered for rice crop and treated to an area 1.41 times the rice acreage ; more than 30 herbicides were registered for field crops and treated to 89% of the crop area ; the treatment acreage of 3 non-selective foliar-applied herbicides reached 2,555 thousand hectares. During the last 25 years herbicides have benefited the Korean farmers substantially in labor, cost and time of farming. Any herbicide which causes crop injury in ordinary uses is not allowed to register in most country. Herbicides, however, can cause crop injury more or less when they are misused, abused or used under adverse environments. The herbicide use more than 100% of crop acreage means an increased probability of which herbicides are used wrong or under adverse situation. This is true as evidenced by that about 25% of farmers have experienced the herbicide caused crop injury more than once during last 10 years on authors' nationwide surveys in 1992 and 1993 ; one-half of the injury incidences were with crop yield loss greater than 10%. Crop injury caused by herbicide had not occurred to a serious extent in the 1960s when the herbicides fewer than 5 were used by farmers to the field less than 12% of total acreage. Farmers ascribed about 53% of the herbicidal injury incidences at their fields to their misuses such as overdose, careless or improper application, off-time application or wrong choice of the herbicide, etc. While 47% of the incidences were mainly due to adverse natural conditions. Such misuses can be reduced to a minimum through enhanced education/extension services for right uses and, although undesirable, increased farmers' experiences of phytotoxicity. The most difficult primary problem arises from lack of countermeasures for farmers to cope with various adverse environmental conditions. At present almost all the herbicides have"Do not use!" instructions on label to avoid crop injury under adverse environments. These "Do not use!" situations Include sandy, highly percolating, or infertile soils, cool water gushing paddy, poorly draining paddy, terraced paddy, too wet or dry soils, days of abnormally cool or high air temperature, etc. Meanwhile, the cultivated lands are under poor conditions : the average organic matter content ranges 2.5 to 2.8% in paddy soil and 2.0 to 2.6% in upland soil ; the canon exchange capacity ranges 8 to 12 m.e. ; approximately 43% of paddy and 56% of upland are of sandy to sandy gravel soil ; only 42% of paddy and 16% of upland fields are on flat land. The present situation would mean that about 40 to 50% of soil applied herbicides are used on the field where the label instructs "Do not use!". Yet no positive effort has been made for 25 years long by government or companies to develop countermeasures. It is a really sophisticated social problem. In the 1960s and 1970s a subside program to incoporate hillside red clayish soil into sandy paddy as well as campaign for increased application of compost to the field had been operating. Yet majority of the sandy soils remains sandy and the program and campaign had been stopped. With regard to this sandy soil problem the authors have developed a method of "split application of a herbicide onto sandy soil field". A model case study has been carried out with success and is introduced with key procedure in this paper. Climate is variable in its nature. Among the climatic components sudden fall or rise in temperature is hardly avoidable for a crop plant. Our spring air temperature fluctuates so much ; for example, the daily mean air temperature of Inchon city varied from 6.31 to $16.81^{\circ}C$ on April 20, early seeding time of crops, within${\times}$2Sd range of 30 year records. Seeding early in season means an increased liability to phytotoxicity, and this will be more evident in direct water-seeding of rice. About 20% of farmers depend on the cold underground-water pumped for rice irrigation. If the well is deep over 70m, the fresh water may be about $10^{\circ}C$ cold. The water should be warmed to about $20^{\circ}C$ before irrigation. This is not so practiced well by farmers. In addition to the forementioned adverse conditions there exist many other aspects to be amended. Among them the worst for liquid spray type herbicides is almost total lacking in proper knowledge of nozzle types and concern with even spray by the administrative, rural extension officers, company and farmers. Even not available in the market are the nozzles and sprayers appropriate for herbicides spray. Most people perceive all the pesticide sprayers same and concern much with the speed and easiness of spray, not with correct spray. There exist many points to be improved to minimize herbicidal phytotoxicity in Korea and many ways to achieve the goal. First of all it is suggested that 1) the present evaluation of a new herbicide at standard and double doses in registration trials is to be an evaluation for standard, double and triple doses to exploit the response slope in making decision for approval and recommendation of different dose for different situation on label, 2) the government is to recognize the facts and nature of the present problem to correct the present misperceptions and to develop an appropriate national program for improvement of soil conditions, spray equipment, extention manpower and services, 3) the researchers are to enhance researches on the countermeasures and 4) the herbicide makers/dealers are to correct their misperceptions and policy for sales, to develop database on the detailed use conditions of consumer one by one and to serve the consumers with direct counsel based on the database.

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Evaluation of Antimicrobial, Antioxidant, and Antithrombin Activities of the Rhizome of Various Dioscorea Species (마 품종별 메탄올 추출물의 항균, 항산화 및 항혈전 활성 평가)

  • Kwon, Jung-Bae;Kim, Mi-Sun;Sohn, Ho-Yong
    • Food Science and Preservation
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    • v.17 no.3
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    • pp.391-397
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    • 2010
  • Yams (Dioscorea spp.) have been used as medicinal and edible resources worldwide. In the present study, methanol extracts were prepared from various kinds of yam, including D. batatas (Gyeongbuk No. 1 and No. 4), D. alata L. (Gyeongbuk No. 5 and No. 6), and D. bulbifera and D. nipponica, and the antioxidant, antithrombin, and antimicrobial activities of these extracts were evaluated. The water content of the various yams was 54.7~83.2% (D. batatas> D. alata L.>D. nipponica>D. bulbifera) and the methanol extracts contained 0.59-1.59% (w/v) solid matter (D. alata L.>D. batatas >D. nipponica>D. bulbifera). The mean concentrations of total polyphenols, total flavonoids, and total sugars in the different types of yam were 49.82 mg/g, 9.79 mg/g, and 173.81 mg/g, respectively. Analysis of DPPH radical-scavenging activity showed that D. alata L. Gyeongbuk No. 6 had a strong antioxidant capacity (IC50=$142.30{\mu}g/mL$), whereas the other yams showed reduced levels of activity (IC50=371-$486{\mu}g/mL$). D. alata L. Gyeongbuk No. 6 showed a strong antithrombin activity against human thrombin. Upon treatment with a D. alata methanol extract (1.5 mg/mL), thrombin time was increased 7.35-fold compared with that when methanol alone was used. In an antimicrobial activity assay, the D. nipponica extract showed moderate antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Proteus vulgaris, and Salmonella typhimurium. Our results indicate that different varieties of Dioscorea spp., including D. batatas, have useful biochemical attributes, including antioxidant, antithrombin, and antibacterial activities.

Effects of Tea Beverages on Cadmium Accumulation and Excretion in Rats Given Cadmium (차 음료가 카드뮴 섭취 흰쥐의 카드뮴 축적과 배설에 미치는 영향)

  • Kim, Tae-Kyung;Park, Bum-Ho;Lee, Sang-Il;Kim, Soon-Dong
    • Food Science and Preservation
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    • v.15 no.1
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    • pp.161-168
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    • 2008
  • The effects tea beverages (TBs) prepared from powdered green tea (Gt), oolong tea (Ot), black tea (Bt), or pure tea (Pt) with lemon, orange, grenadine etc on cadmium toxicity in rats were investigated Sensory evaluations of the TBs are better than those of each water extracted teas. Cadmium (50 ppm) was administered to experimental rats fed a basic diet, or a diet with various TBs (15% w/v), for 5 weeks. Although body weight gains, feed intakes, and fecal weights in all Cd-treated groups were lower than those in the normal control group (NC), feed efficiency ratio, urine volumes, liver weights, and kidney weights did not differ significantly between groups. The serum ALT and AST levels in the Cd-treated control group (Cd-Co) were higher than those in the NC animals. Serum ALT and AST levels in all Cd-treated rats fed TB-supplemented diets were lower than in animals of the Cd-Co group. Tibia and femur weights in Cd-Co animals were lower than those in NC rats. Tibia and femur weights in Cd-treated rats fed TB-supplemented diets were higher than those in Cd-Co animals. There were no between-group differences in tibia lengths; animals in the NC and TB-supplemented diet groups showed femur lengths longer than those of Cd-Co rats. Although the contents of crude ash and cadmium in the femurs of Cd-Co mts was markedly higher than in the femurs of NC animals, the cadmium content in femurs of Cd-Co rats was significantly lower than that in the femurs of NC animals. The changes in mineral levels caused by Cd administration were alleviated by every TB-supplemented diet tested Whereas fecal calcium excretion by Cd-Co animals was significantly higher than that of NC rats, calcium excretion by Cd-treated rats fed TB-supplemented diets was significantly lower than that of Cd-Co animals. Fecal cadmium excretion by all Cd-treated rats fed TB-supplemented diets was significantly higher than that of Cd-Co animals. In conclusion, this study provides experimental evidence that various TBs may regulate cadmium-induced organ toxicity by reducing cadmium accumulation in tissues through the mechanism of increasing the fecal excretion of cadmium.