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Studies on Microbiological and Chemical Changes of Milk Treated by High Temperature (고온처리(高溫處理)에 의한 우유(牛乳)의 미생물(微生物) 및 화학적(化學的) 변화(變化)에 관한 연구(硏究))

  • Shin, Yong Kook;Kim, Jong Woo
    • Korean Journal of Agricultural Science
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    • v.13 no.2
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    • pp.198-209
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    • 1986
  • This study was conducted to find optimum heating temperature and time as milk was heated over a wide range of temperature and time combinations at $70{\sim}100^{\circ}C$ into $5^{\circ}C$ interval for 10, 15 and 20 second. The results obtained were summarized follows: 1. The effects of heat treatment on the bacteria by $75^{\circ}C/20s$, $80^{\circ}C/10s$ and $100^{\circ}C/20s$ were 99.56%, 99.52% and 99.92% respectively. 2. Sterilized rate of milk which was added Bacillus subtilis by $75^{\circ}C/20s$, $80^{\circ}C/10s$ and $100^{\circ}C/20s$ were 99.23%, 99.25% and 99.85% respectively. 3. The pH value fell in accordance with the increasing of heating temperature. 4. Content of protein, fat and lactose was not changed by heat treatment. 5. The content of total nitrogen was not changed. The content of casein nitrogen and non - protein nitrogen increased, but non - casein nitrogen reduced, according to heat trea ted of milk. 6. According to the increasing of heating and time, filter - passing nitrogen reduced. 7. The artificial digestibility was increased when milk was heated from $70^{\circ}C$ to $100^{\circ}C$ into $5^{\circ}C$ interval at 10, 15 and 20 second.

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Biochemical Composition and Antioxidative Activity of Marine Microalgae (해양 미세조류의 생화학적 조성 및 항산화성)

  • KIM Se-Kwon;BAEK Ho-Chul;BYUN Hee-Guk;KANG Ok-Ju;KIM Jong-Bae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.3
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    • pp.260-267
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    • 2001
  • The biochemical composition and antioxidative activity of marine microalgae were investigated for the effective utilization of marine resources. Two species of marine microalgae, Nannochloris oculata (N. oculata) of Chlorophyceae and Phaeodactylum tricornutum (P. tricornutum) of Bacillariophyceae, were selected. Because these species showed the high growth rate and easy to continuous culture. The contents of crude protein, lipid, and carbohydrate were $54.91\%,\;11.29\%,\;and\;10.15\%$, for N. oculata and $38.07\%,\;13.19\%,\;and\;7.13\%$, for P. tricornutum, respectively. Glutamic acid was the highest concentration for both species. Galactose (3,712.02 mg/100g), fucose (1,966.03 mg/100g), and glucose (1,814.35 mg/100g) were the major carbohydrates for N. oculatae, and glucose (5,295.45 mg/100g) and mannose (841.34 mg/100g) were for P. tricornutum. K (12,906.86 mg/100g), Mg (1,039.15 mg/100g), Ca (882.57 mg/100g) and Fe (747.20 mg/100g) were the major minerals for N. oculata, and K (11,718.65 mg/100g), Ca (2,003.32 mg/100g), Mg (1,570.84 mg/100g) and Fe (552.58 mg/100g) were for P. tricornutum. In the composition of nucleotides, ADP ($4.77{\mu}mol/g$) was the highest in N. oculata and hypoxanthine (11.74{\mu}mol/g) in P. tricornutum. Large amount of linoleic acid (18: 2, $\omega-6$) was contained in N. oculata. In contrast 16: 1 ($\omega-7$) and 20: 5 ($\omega-3$) were major fatty acid in P. tricornutum. The antioxidative activities of organic solvent extracts of two microalgae were measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay method. The chloroform extract obtained from P. tricornutum was identified to be the most effective in DPPH radical scavenging activity.

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Biological Activity of Extracts from Chrysanthemum incidicum Linne by Ultrafine Grinding (미세분쇄에 의한 감국(Chrysanthemum incidicum Linne) 추출물의 생리활성)

  • Cho, Young-Je
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.1
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    • pp.110-117
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    • 2014
  • In this study, the biological activity of water and ethanol extracts from Chrysanthemum incidicum Linne by ultrafine grinding for functional food source are examined. The content of phenolic compounds from Chrysanthemum incidicum Linne were the highest when extracted for 6 hr with 70% ethanol. The extraction yield of water and ethanol extracts were $7.12{\pm}1.61$ mg/g and $7.51{\pm}2.14$ mg/g, respectively. With ultrafine grinding, water and ethanol extracts were $8.63{\pm}1.15$ mg/g and $9.33{\pm}1.35$ mg/g, respectively. In determining anti-oxidative activity of Chrysanthemum incidicum Linne extracts, DPPH of normal grinding extracts was 83.52% and ultrafine grinding was 92.37%. In ABTS radical cation decolorization, normal grinding, fine grinding, and ultrafine grinding extracts were 90% or higher. In antioxidant protection factor (PF), water and ethanol extracts of ultrafine grinding showed relatively high anti-oxidative activities of each 1.82 PF and 2.16 PF, respectively. The TBARS value of ultrafine grinding extracts were lower than normal grinding and fine grinding extracts. The inhibition activity on xanthin oxidase of Chrysanthemum incidicum Linne extracts was 67.53% in ultrafine grinded water extracts and 83.45% in ultrafine grinded ethanol extracts. Inhibition on xanthin oxidase of ethanol extracts showed a higher inhibition effect than water extracts, and ultrafine grinding was higher than normal grinding. In angiotensin converting enzyme inhibition activity, ultrafine grinding water extract was 24% or higher, and ethanol extract was 34% or higher. The elastase inhibition activity of ultrafine grinding extract was 25.56%, which was higher than 20.34% of fine grinding extracts. Water extracts did not show hyaluronidase inhibition activity but ethanol extracts showed 35% of hyaluronidase inhibition activity. The determining expression inhibition of iNOS and COX-2 protein in macrophage by Chrysanthemum incidicum Linne extracts with a Western blot analysis, iNOS and COX-2 protein expression inhibition by Chrysanthemum incidicum Linne ethanol extracts were 40% and 15%, respectively at 100 ${\mu}g/mL$ concentration. The inhibitory patterns of iNOS and COX-2 protein expression was concentration dependent. The result suggests that Chrysanthemum incidicum Linne extracts by ultrafine grinding may be more useful than normal grinding as potential sources due to anti-oxidation, angiotensin converting enzyme and xanthine oxidase inhibition, anti-inflammation effect.

Effects of Planting Soil on the Soil Moisture and the Growth of Vitex rotundifolia for Green Roof (옥상녹화 식재지반이 토양수분과 순비기나무의 생육에 미치는 영향)

  • Park, Jun-Suk;Park, Je-Hea;Ju, Jin-Hee;Yoon, Yong-Han
    • Journal of the Korean Institute of Landscape Architecture
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    • v.38 no.3
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    • pp.98-106
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    • 2010
  • This study focuses on the appropriate planting soil for Vitex rotundifolia by planting soil. Different soil depth levels were achieved at 15cm and 25cm in the green roof module system that was created with woody materials for a $500{\times}500{\times}300mm$ area. The soil mixture ratio was $S_{10}$, $L_{10}$, $S_7L_3$, $S_5L_5$, $P_7P_1L_2$, $P_6P_2L_2$, $P_5P_3L_2$ and $P_4P_4L_2$. This study was carried out over five months between April and September, 2006. The amount of soil moisture tends to decrease according to the planting soil. For the experimental items $S_{10}$, $S_7L_3$ and $S_5L_5$, the amount of soil moisture tends to decrease rapidly. However, for the experimental items $P_7P_1L_2$, $P_6P_2L_2$, $P_5P_3L_2$ and $P_4P_4L_2$, conditions containing perlite and peat moss, the amount of moisture tends to decrease more gradually. As a result, the use of soil-improving amending for the afforestation planting of roofs with a low level of management is need. After experimenting with the ratio of soil mixture for Vitex rotundifolia, the planting soil for experimental item $P_6P_2L_2$, $P_5P_3L_2$ and $P_4P_4L_2$ appeared excellent. For experimental item $S_{10}$, the growth of Vitex rotundifolia seemed to be weaker than that of others, because of the low levels of moisture and organic matter in the soil. For experimental item $L_{10}$, there appeared to be a low level of growth, even when the levels of moisture and organic matter were high. This may have occurred because of the low level of soil pH and the excessive amount of exchangeable cation. At the depth of 25cm, the growth of Vitex rotundifolia is vigorous overall. For experimental item at 15cm, Vitex rotundifolia was able to survive for 14 days without any rainfall and Vitex rotundifolia was better in amended soil, $P_6P_2L_2$, $P_5P_3L_2$ and $P_4P_4L_2$, than natural soil, SL.

The Effect of Integrated Mind Map Activities on the Creative Thinking Skills of 2nd Year Students in Junior High School (통합형 마인드맵 활동이 중학교 2학년 학생들의 창의적 사고력에 미치는 영향)

  • Yoon, Hyunjung;Kang, Soonhee
    • Journal of the Korean Chemical Society
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    • v.59 no.2
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    • pp.164-178
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    • 2015
  • The purpose of this study was to design a teaching and learning method conductive to the development of creative thinking skills and investigate its effects. It has been developed integrated mind map with feature of visualizing the divergent thinking to the aspects of Science (S), Technology (T) & Engineering (E), Arts (A), Mathematics (M). Integrated mind map can be divided into four types of STEAM type, STEA type, STEM type, STE type depending on the category of key words in the first branch. And Integrated mind map can be divided into three levels of guided, intermediate, open depending on the teacher's guide degree. And also integrated mind map activities were carried out in the form of group, class share as well as individual. This study was implemented during a semester and students in experiment group experienced individual-integrated mind map activity 10 times, group-integrated mind map activity 10 times, class share-integrated mind map activity 3 times. The results indicated that the experimental group presented statistically meaningful improvement in creative thinking skills (p<.05). And there was a statistically meaningful improvement in fluency, flexibility, originality as a sub-category of creative thinking skills(p <.05). Also creative thinking skills are not affected by the level of cognitive, academic performance, gender (p<.05). In conclusion, it was found that 'integrated mind map activity' improved student's creative thinking skills. There was no interaction effect about creative thinking skills between the teaching strategy and cognitive level, achivement, gender of those students.

Factors Affecting the Weight Control Intention of the Female Adolescent by Body Size - In Daegu Area - (청년기 여성의 체형에 따른 체중조절 행동의도에 영향을 미치는 요인 분석 - 대구지역을 중심으로 -)

  • Ryu, Ho-Kyung
    • The Korean Journal of Community Living Science
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    • v.16 no.4
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    • pp.83-93
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    • 2005
  • This study was conducted to provide information about the behavioral intentions to diet in adolescent females. To explain the behavior intention to diet, a conceptual framework based on the ' Social Support, Control and the Stress Process Model ' and the ' Theory of Reasoned Actio ' was used. The survey was carried out by self-questionnaires with 463 female high school and college students in Daegu. Analysis of data was done by using mean, correlation and multiple regression analysis with the SAS computer program. Subjects were divided into 3 groups-underweight, normal weight, and overweight-according to their current body size. The most powerful influencing factor related to perceived stress -that is dissatisfaction with body image- was the current figure, regardless of current body size. The fatter the current body size, the higher the score for the behavioral intention to diet. In attitude toward the behavior of dieting, the fatter the current figure, the higher the attitude score, and the belief of behavioral outcome was the main decision variable. For the score of the subjective norm, the overweight group was significantly higher than other groups. The influencing factors for the behavioral intention to diet were perceived stress and attitude toward dieting behavior, especially beliefs of behavioral outcome.

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Management Plan for Humanistic and Ecological Characteristics of Suweol Village Forest in Tongyoung (통영 수월숲의 인문학적 특성 및 생태적 특성을 고려한 관리방안)

  • Lim, Eui-Jea;Lee, Soo-Dong;Kim, Mi-Jeong
    • Korean Journal of Environment and Ecology
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    • v.27 no.1
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    • pp.85-98
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    • 2013
  • In order to propose effective conservation management plan, this study verified ecological characteristics, humanities and Social characteristics. The research site is private property which is owned belonging to the Kim's of Gimhae that have long history. The study site is more than a thousand years old and was created for protecting from typhoon. There held the religious ritual what is called Dongsinje until 1960s. There have been protected and managed by the villagers. As the results of analysis, the area of windbreak are $12,392.69m^2$. The windbreak is dominated old years deciduous broad-leaved tree such as Zelkova serrata, Celtis sinensis, Aphananthe aspera. Around there were farmlands(52.1%), urbanized area(26.3%), forest area(16.6%). The vegetation communities of windbreak were classified by considering the dominant species and current status of forest. The forest types are following as; A. aspera community(I) which is using less pressure, Platycarya strobilacea-Carpinus coreana-Z. serrata community(II). Z. serrata community(III) which is using high pressure, Z. serrata-A. aspera community(IV), Z. serrata community(V) which is damaged under canopy trees. The windbreak was in good condition whereas, there were concerns the some wrong status was being undermined such as the wrong forest restoration projects in the past, the trails that is penetrating inside the forest, building up education facilities. Therefore, in order to restore the value of windbreak what is so called Suwol forest, we should improve the problems of forest ecosystem such as wrong management, forest fragmentation by facilities and decline in forest by lack of growing the next generation trees. In addition, we should remove excessive resting facilities and lead to passive use of forest. to improve the way of wrong management, moreover, we should close off he trails that is penetrating inside the forest for improving fragmentation. We should restore vegetation restoration and fostering the next generation trees for forest ecosystem. In order to restore unique of histo-cultural and ecological forest landscape, the next generation trees should be grown up that is the dominant species in Suwol forest. Moreover, as a results of comparing the between good vegetation communities and damaged vegetation communities, it is necessary to complementary planting for demeged vegetation communities, therefore there needs to 10.8 under canopy trees, 79.7 shrubs.

Case Study of Teaching Practices of Biology Teachers with and without Research Experience in Evolution Education (진화 교육 연구 경험 유무에 따른 생명과학 교사의 교수 실행 사례 연구)

  • Ko, Yuseon;Cha, Heeyoung;Lim, Mili
    • Journal of The Korean Association For Science Education
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    • v.37 no.4
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    • pp.747-761
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    • 2017
  • The purpose of this study is to analyze differences in the teaching practices of biology teachers according to their awareness of the importance of evolution. For this purpose, two teachers who experienced study of evolution and recognized its importance, along with two teachers with no experience in evolution education in the comparison group, were included in the sample. To observe teaching practices, two classes each on biological evolution and non-evolution were selected, recorded and transcribed. The content analyzed included the teachers' view on evolution education and teachers' evolution concepts reflected in teaching practice. As a result, the level of understanding of the teachers' evolution concept was unrelated to teachers' awareness of the importance of evolution. Instead, each teacher would not feel the need for religious beliefs or awareness of the importance of evolution to have a negative impact on the awareness of the importance of evolution. Inexperienced teachers tend to reject the retraining opportunities to recognize the importance of evolution. In addition, inexperienced teachers were only superficially aware of the evaluation and improvement of evolution presented in textbooks and curricula. In actual teaching practice analysis, inexperienced teachers' utilizing ratio of the evolution key concept was higher than that of experienced teachers. Only experienced teachers were aware of the misconceptions presented in their execution and described the causes that appear in these misconceptions. Teachers who recognized the importance of evolution were widely using the key concepts of evolution, as well as more practical in preventing the misconceptions related to evolution forms. It indicates that biology teachers who do not realize the importance of evolution in biology education need to experience explicit and practical education programs as well as instructional materials on evolution.

Corn-zein Laminated Carrageenan Film for Packaging Minced Mackerels (옥수수단백/카라기난 적층필름의 다진 고등어육의 포장특성)

  • Park, Jeong-Wook;Park, Hyun-Jin;Jung, Soon-Teck;Rhim, Jong-Whan;Park, Yang-Kyun;Hwang, Keum-Taek
    • Korean Journal of Food Science and Technology
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    • v.30 no.6
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    • pp.1381-1387
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    • 1998
  • Laminated films were prepared by casting corn-zein and fatty acid mixed solutions onto ${\kappa}-carrageenan$ films, and the effect of various fatty acids with different concentrations on the film properties such as water vapor permeabilities (WVP), tensile strength (TS) and elongation was investigated. WVP of the film decreased as concentration of fatty acids increased, and the lowest WVP value $(0.497\;ng\;m/m^2\;s\;Pa)$ was achieved with laminated films containing 30% lauric acid/corn-zein. The TS of laminated edible film seemed to decrease as the concentration of fatty acids increased, and TS of the laminated film was the highest (36.21 MPa) when the film contained 10% oleic acid. Weight loss of the minced mackerels packaged with corn-zein/carrageenan film which did not contain fatty acid was 11.7%, but weight losses of the samples packaged with oleic acid and lauric acid were 6.97% and 0.81%, respectively, after 30 days storage at $-20^{\circ}C$. The laminated films had an effect on preventing oxidation of the minced mackerels during storage because of high oxygen barrier property of the film. All of the minced mackerels packaged with the laminated films greatly reduced the peroxide value (POV) compared with unpackaged minced mackerels during storage. Also, thiobarbituric acid (TBA) values of the minced mackerels packaged with the laminated films were lower than that of unpackaged minced mackerels during storage.

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Accumulation of oxyresveratrol in Ramulus mori upon postharvest storage (숙성에 의한 뽕나무 상지 내 옥시레스베라트롤 축적)

  • Kim, Jun-Ho;Kim, Ki-Hyun;Lee, Min-Young;Lim, Young-Hee;Kim, Jeong-Keun
    • Korean Journal of Food Science and Technology
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    • v.50 no.1
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    • pp.98-104
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    • 2018
  • Oxyresveratrol (trans-2, 3', 4, 5'-tetrahydroxystilbene), found in many plants including grape, peanut and mulberry, is a phytoalexin, an antimicrobial and antioxidative substance that rapidly accumulates in areas infected by the pathogen. We examined the accumulation of oxyresveratrol in nine Morus alba L. cultivars with respect to storage time and temperature postharvest and infection with GRAS microorganisms. Among the nine cultivars, the Suwon cultivar showed the highest oxyresveratrol content (9.6-fold increase) postharvest, when stored at $30^{\circ}C$ for 7 days. The optimal temperature and postharvest storage time for oxyresveratrol accumulation was $30^{\circ}C$ and 6 days. When Ramulus mori was infected with five microorganisms, the accumulation of oxyresveratrol increased over 4-fold in response to B. coagulans infection. These results suggest that oxyresveratrol accumulation is influenced by storage temperature, storage time, Ramulus mori cultivars, and microbial attack. Therefore, postharvest storage for an appropriate time period at a suitable temperature might be a useful way to industrially produce Ramulus mori cultivars with high oxyresveratrol content.