• Title/Summary/Keyword: Science for all

Search Result 31,047, Processing Time 0.076 seconds

Physico-chemical Characteristics of Yogurt by Lactobacillus spp. from Pickles (젓갈에서 분리한 Lactobacillus spp.로 제조한 요구르트의 이화학적 특성)

  • Rhee, Young-Hwan;Na, Han-Ju;Lee, Yong-Kyu;Shin, Seung-Yee;Kim, Jong-Hyun
    • Applied Biological Chemistry
    • /
    • v.40 no.1
    • /
    • pp.12-17
    • /
    • 1997
  • Three strains of lactic acid bacteria were isolated from fish and shrimp pickles. Two strains were identified as Lactobacillus casei, and one strain as L. Pentosus, respectively. All three strains were used as starters in producing yogurts. The physico-chemical characteristics of yogurts were examined. The original pH, titratable acidity, visicosity and viable cell counts of the yogurts were $4.03{\sim}4.26,\;1.049{\sim}l.217%,\;1,772{\sim}2,232\;cps\;and\;1.4{\times}10^9{\sim}1.6{\times}10^9\;cfu/ml$, respectively. In evaluating buffer capacity, $12.50{\sim}14.06\;ml$ 1.0N HCl was consumed to titrate 100 ml of yogurt to pH value 2 units below the original pH value and $9.46{\sim}13.06\;ml$ of 1.0N NaOH was consumed to pH value 4 units above the original pH value. The ${\beta}-galactosidase$ activity reached maximum at 48 hrs, and reduced gradually during fermantation. After 2 hr incubation of yogurts at $37^{\circ}C$ under different pH conditions, ${\beta}-galactosidase$ activities of three strains were reduced to 50% at pH 3.5, but there were no remaining activities neither at pH 2.5 nor at pH 1.5. Under the same pH conditions the number of viable cells decreased to $1.9{\times}10^6{\sim}1.8{\times}10^8\;cfu/ml$ at pH 2.5 and $1.0{\times}10^3{\sim}2.4{\times}10^5$ at pH 1.5, respectively. However, no significant difference was found at pH 3.5.

  • PDF

Effect of Monascus Pigment Extract on the Alcohol Metabolism in Rats (흰쥐에 있어서 홍국 색소 추출물이 알코올대사에 미치는 영향)

  • 유대식;최혜정;윤종국
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.32 no.4
    • /
    • pp.603-607
    • /
    • 2003
  • To investigate the alcohol metabolizing system in liver of rats drunken 10% ethanol with Monascus pigment extract (MPE), Sprague-Dawley male rats weighing about 250 g have been drunken 10% ethanol containing 1, 2.5 and 5% Monascus pigment extract for a month. Three groups of rats drunken 10% ethanol with MPE gained somewhat less body weight than normal group, but the changes of body weight was not significantly different among the former groups. All groups drunken MPE supplemented alcohol had no remarkable changes in liver function on the basis of liver weight/body weight, the serum levels of alanine aminotransferase and xanthine oxidase activity. 10% alcohol drunken animals (control group) showed significantly increased activity of hepatic alcohol dehydrogenase (ADH) by 87% compared with normal group and the animals drunken 1%, 2.5% and 5% MPE showed respectively 34%, 29% and 21% increased activity of hepatic ADH, whileas Km value of ADH in 1, 2.5 and 5% MPE group decreased by 40%, 30% and 19% respectively compared with the control, but Vmax showed no significant changes among MPE groups. In case of aldehyde dehydrogenase (ALDH), 1% MPE group showed significantly increased activity by 32% and 2.5% or 5% MPE group showed increasing tendency compared with control, and Km value in three experimental groups declined by 27% and no particular changes were found among those. Furthermore, Vmax value in 1, 2.5 and 5% MEP group increased by 88,56 and 22% respectively with the control. In the aspect of the area under the curve of a ethanol concentration versus time (AUC) profile obtained after administration of 10% alcohol with 1 or 5% MPE, the decreasing rate of AUC to the control was 18% in 1% MPE treated rats whereas 10% in 5% MPE group.

Tooth color changes associated with the bracket bonding and debonding (교정치료 시 브라켓 부착 및 제거에 따른 치아색 변화)

  • Kim, Seok-Pil;Hwang, In-Nam;Cho, Jin-Hyoung;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
    • /
    • v.36 no.2 s.115
    • /
    • pp.114-124
    • /
    • 2006
  • The purpose of this study was to evaluate the tooth color changes of resin bonding sites and their adjacent sites on orthodontic bracket bonding. Sixty extracted sound premolars were used and the tooth color was recorded according to the CIE $L^*a^*b^*$ color system using a spectrophotometer. The tooth colors of the twenty premolars were measured and compared before bracket bonding and after removal. On a further twenty premolars, the tooth color was measured before and after only primer application. In the change of $L^*$ values, according to the bracket bonding and primer application, the lightness was decreased, and in the change of $a^*\;and\;b^*$ values, the color was changed into a more yellowish color The color differences $({\Delta}E^*)$ were calculated from the $L^*a^*b^*$ values and compared with the standard value of clinical detection $({\Delta}E^*=3.7)$. The color differences between before the bracket bonding and after removal noted exceeded the standard value and those of between before and after the primer application were not larger than the standard value. Toothbrushing was performed after application of the primer to evaluate the color changes according to the primer abrasion. As a control, toothbrushing was performed on the last twenty premolars. The color differences noted were larger than the standard value after toothbrushing. Also, to evaluate the color changes of the tooth which is exposed to sun irradiation after bracket removal, additional photoaging was performed and the color was measured for all teeth. The additional color differences after photoaging were smaller than the standard value. The above results suggest that the tooth color changes after fixed orthodontic treatment.

Effect of Some Factors on the Variation of Nutrient Level in Pinus rigida × taeda Needle (Pinus rigida × taeda 침엽내(針葉內) 양료수준(養料水準)의 변이(変異)에 관(関)한 몇가지 요인(要因)의 영향(影響))

  • Kim, Chi Moon;Kwon, Ki Won;Song, Ho Kyung;Kim, Chung Suk
    • Journal of Korean Society of Forest Science
    • /
    • v.53 no.1
    • /
    • pp.27-36
    • /
    • 1981
  • Foliar nutrient concentrations of N, P, K, Ca, Mg, total sugar, starch, ether extracts were determined for three Pinus spp., that is, P. rigida, P. taeda, P. rigida${\times}$taeda, divided by tree age (16~19-year old, 6-year old), leaf age (current, over-winter, one-year old), planting location(Kyonggi-Do, Chungnam-Do, Junbuk-Do). Foliar compositions of inorganic nutrients were generally put in order of N(0.764~1.502%)>K((0.130~0.491%) $$\geq_-$$Ca(0.165~0.442%)>Mg(0.054~0.121%)${\fallingdotseq}$P(0.041~0.129%) in all the species. The concentrations of total sugar and ether extracts respectively ranged from 5 to 15% of the needles in dry weight base. The concentrations of N, P and K were similarly high in the over-winter needles (sampled in February), but those of Ca were generally high in one-year old needles. As a whole, inorganic nutrient levels in the needles showed different patterns with species, three age, leaf age and location. There were generally positive correlations between nitrogen and phosphorus in foliar concentrations. Foliar concentrations of total sugar showed the ranking of P. rigida > P. rigida${\times}$taeda > P. taeda and the lowest levels in February. Starch in the needles were contained about 10% of total sugar, and the variations of starch level were not regular with the studied factors. Ether extracts contents increased more of less with leaf age but changed irregularly with the other factors.

  • PDF

Socio-Economic Variables and Attitudes of Forest Owners toward Cooperative Management (협업경영(協業經營)에 대(對)한 산주태도(山主態度)와 사회경제적변수(社會經濟的變數))

  • Cho, Eung Hyouk
    • Journal of Korean Society of Forest Science
    • /
    • v.53 no.1
    • /
    • pp.56-61
    • /
    • 1981
  • Total 183 private forest owners in Chungnam-Do were surveyed in order to analyse the attitudes toward cooperative forest management and to find out the relationship of the attitudes with such socio-economic variables as owners' socio-economic status(SES), age and educational level. Major findings of the study are summarized as follows:- 1. Only 17.5 percent of the owners regards the cooperative management as a desirable alternative for the management of private forests. Significant difference of their attitudes is recognized only among the classes of the educational level. 2. About one-third of the owners wishes to participate to a cooperative, if established. The owners' intention of participating is positively related to the degree of S.E.S. and educational level, but negatively associated with that of age variable, and the differences among the classes of all variables are significant at the 0.01 or 0.05 levels. 3. More than half of the owners desires to have limited cooperatives, in which the members themselves manage their forest land with some management aspects being handled by the cooperative such as procurement of seedlings, protection measures, and marketing. The difference of responses among the classes of educational level is significant at the 0.01 level. 4. The owners, who agree with the idea of voluntary membership in the cooperative, are about 45 percent of the total. Significant difference is found only among the classes of the S.E.S. variable. 5. Nearly 60 percent of the owners wants to have self-help cooperative organizations. Significant difference of responses is recognized only among the classes of the age variable.

  • PDF

Studies on Forest Soils in Korea (II) (한국(韓國)의 삼림토양(森林土壤)에 관(關)한 연구(硏究) (II))

  • Lee, Soo Wook
    • Journal of Korean Society of Forest Science
    • /
    • v.54 no.1
    • /
    • pp.25-35
    • /
    • 1981
  • Some physical and chemical properties of forest soils in Korea were analyzed for providing the reasonable management methods of forest lands, Among 375 soil series surveyed until 1979, 93 soil series of forest soils were classified and analyzed according to their characteristics. Firstly soil data were classified into 5 categories by weathered products and secondly were classified and analyzed by parent rocks. The results are as follows: 1) In forest soils characterized by weathered products volcanic ash soils were proved to be the most fertile and alluvial soils were turned out to be the most infertile soils. Residual soils on mountain and hill were mostly on the average in all kinds of soil properties analyzed except total soil depth. 2) Igneous rocks developed rather infertile soils containing large amount of organic matter and available $P_2O_5$ with relatively deep soil depth and strong acidity. On the other hand sedimentary rocks produced rather shallow soils containing small amount of organic matter and available $P_2O_5$ but they were relatively fertile with weak acidity. 3) Among igneous rocks basalt and trachyte produced very fertile soils and granite and andesite produced slightly infertile soils. 4) Among sedimentary rocks limestone soils had high fertility neutral in acidity but low amount of available $P_2O_5$ 6) Alluvial sand produced generally very infertile soils with great soil depth comparing with the arable alluvial land with high fertility.

  • PDF

Identification of Leaf Characteristics from Various Crosses in Relation with Populus glandulosa U. (Populus glandulosa U.에 유사(類似)한 교잡종(交雜種)의 엽특성(葉特性))

  • Son, Doo Sik;Yim, Kyong Bin
    • Journal of Korean Society of Forest Science
    • /
    • v.45 no.1
    • /
    • pp.1-10
    • /
    • 1979
  • This study was conducted to widen the range of characteristics of the hybrids, P.alba ${\times}$ P.glandulosa, i.e. aiming for gene population expansion P.glandulosa seemed to have the similar characteristics as the one segregated from the natural hybrids between P.alba and P.davidiana. Thus the main objectives of this study were to make many crosses among poplars and then to identify leaf characteristics of the crosses similar to P.glandulosa, the results obtained can be summerized as follows; 1. Leaf characteristics such as leaf margin, presence of glands at leaf base and pubescence density, of crosses made from P.alba.davidiana ${\times}$ P.datidiana, and P.davidiana.alba ${\times}$ P.davidina showed 44% and 90%, respectively, of similarity to P.glandulosa. 2. The ratio of leaf size, including leaf length, leaf width, length from leaf base to width line, and petiole length, of the above crosses was similar to P.glandulosa. 3. Pubescence density of the dorsal leaf surface in hybrids between P.alba and P.davidiana showed generally intermediate of the parental appearance. Frequency of pubescence appearance differed from depending upon the use of P.alba, either as a female or a male parent. The use of P.alba as a male parent increased frequency of Pubescence appearance. 4. The presence of glands at the leaf base in P.glandulosa may be inherited from P.davidiana which possesses gland although gland is not present in all P.davidiana rather from P.alba which has no gland.

  • PDF

Improvement of Productivity by Forest Tree Breeding Work in Korea (우리나라에서의 임목육종(林木育種)에 의(依)한 생산성(生産性) 증가(增加))

  • Ryu, Jang Bal;Shim, Sang Yung
    • Journal of Korean Society of Forest Science
    • /
    • v.77 no.4
    • /
    • pp.382-388
    • /
    • 1988
  • Improvement of productivity by forest tree breeding work in Korea was estimated for a few important tree species. Progenies of 17 plus trees of red pine (Pines densiflora) outgrew by 57 percentage compared with progenies of unselected trees at age 15. If best three families are selected among the 17, more than double in volume grow-th is expected. The hybrid Pinus rigida ${\times}$ P. taeda showed more than double volume growth compare to P. rigida at a southern plantation at age 15. However, the superiority of the hybrid decreased at northern plantations, mainly because of low coldhardiness of the hybrid. At a northern plantation, the hybrid grew less than the P. rigida on upper hill, while the hybrid grew much better than the P. rigida on flat area. Another hybrid Populus alba ${\times}$ P. glandulosa grew faster than both parents by two to two and half times according to planting sites at age 10. Introduction of Pinus rigida also showed increased volume growth. Volume increase by selection of best five provenances among 45 at age 12 was estimated as 53 percent compare to progenies of plus trees in Korea, Additional 19 percent of volume increase was expected by selection of the best families within the best provenances. Annual production of chestnuts reached about 70,000 M/T by planting resistant clones to chestnut gall wasp (Dryocosmus kuriphilus), which killed almost all susceptible trees. Although polyploid trees and mutants have been produced by colchicine treatments in over 10 tree species, none of them is economically important Remarkable improvement of productivity is expected by biotechnology in future through selection, hybridization, introduction of foreign genes at cell, cell organelle and gene level, and gene transformation. At present, mass propagation of superior planting materials by tissue culture will increase the productivity.

  • PDF

Effects of Air Pollution and Acid Precipitation on Soil pH and Distribution of Elements in Forest Ecosystem (대기오염(大氣汚染) 및 산성우(酸性雨)가 삼림생태계(森林生態系)의 토양산도(土壤酸度) 및 양료분포(養料分布)에 미치는 영향(影響))

  • Lee, Soo Wook;Min, Ill Sik
    • Journal of Korean Society of Forest Science
    • /
    • v.78 no.1
    • /
    • pp.11-25
    • /
    • 1989
  • Four regions have been selected and surveyed to investigate the effects of air pollution and acid deposition on forest ecosystem. They were Seoul as urban region, Yeochon and Ulsan as industrialized region, and Kangwondo as uncontaminated region. Soil pH and the distribution of elements were analyzed in process of time for three years as well as by distance from pollution sources. In general, forest soils acidified in process of time from pollution sources to suburban areas. Hydrogen ion concentration in forest soils increased in 1988 as much as 60% of that in previous year. Average soil pH values in coniferous forest were 4.45 in Seoul, 4.54 in Yeochon, 4.81 in Ulsan, and 6.03 in Kangwondo. Forest soil pH increased with the distance from pollution sources to suburban areas at constant rate within short ranges (up to 30 km) and at decreasing rate within long ranges (up to 200 km). On the contrary, sulfur content in soils decreased every year except in Yeochon region. Base saturation of forest soils in polluted regions were all below 20% level compared with 70% in Kangwondo region. Active aluminum content in soils increased with the soil acidification at the highest rate in Yeochon, and the next in Ulsan and Seoul. Heavy metal content such as copper and zinc in tree tissues were the lowest in Kangwondo region, and the next in Yeochon, Seoul and Ulsan.

  • PDF

Effect of Sweet Persimmon Wine on Alcoholic Fatty Livers in Rats (흰쥐에서 단감발효주가 알코올성 지방간 형성에 미치는 영향)

  • Nam, Kyung-Sook;Kim, Ju-Youn;Noh, Sang-K.;Park, Joong-Hyeop;Sung, Eon-Gi
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.40 no.11
    • /
    • pp.1548-1555
    • /
    • 2011
  • Persimmons are shown to contain high levels of phenolics. The present study was designed to investigate if a sweet persimmon wine (SPW) would affect the development of alcoholic fatty liver in rats. Initially, male Sprague-Dawley rats were housed singly in stainless steel wire-bottomed cages in a room of controlled temperature and lighting. The rats had free access to a nutritionally adequate AIN-93G diet and deionized water. After the acclimatization period, rats were weight-matched and assigned to the following three groups: two groups were fed 6.7% ethanol or the caloric equivalent of maltose-dextrin in a Lieber-DeCarli diet and the other group was fed the isocaloric Lieber-DeCarli diet containing SPW at the same ethanol level. All three groups were fed their respective diets for 6 weeks. Serum transaminase, cholesterol, and triglyceride levels were measured. Liver lipids and histology were assessed at 6 weeks. The total phenolic content and the antioxidant and free radical scavenging activities of SPW were determined. SPW significantly increased antioxidant and free radical scavenging activities. As markers of liver injury, serum alanine and aspartate transminases were markedly lowered by SPW at 6 weeks. SPW significantly reduced the serum levels of serum cholesterol and triglyceride compared to ethanol treatment. SPW delayed the development of an alcoholic fatty liver by reversing fat accumulation in the liver, as evidenced in histological observations. Taken together, SPW seems to protect the liver from becoming fatty by alleviating fatty liver symptoms and lowering hepatic and serum lipid levels. Such a protective effect of SPW appears to be in part due to its phenolics.