This experiment was carried out to develop the model system for mass production of biomedical and nutritional proteins (human proteins) through mamraary gland of the transgenic cattle produced by gene manipulation and embryological technologies. Human growth hormone gene fused with rat -casein gene promoter was microinjected into pronuclei of one cell bovine embryos produced by in vitro fertilization. After microinjection, embryos were cultured in vitro for 6 or 7 days. Twenty embryos reaching to blastocysts were transferred to 10 beef recipients, each receiving two embryos. Recipients were diagnosed for pregnancy by rectal palpation at 76 days after embryo transfer. One of them was pregnant to term and produced a female calf weighing 21 kg at 280 days following embryo transfer. DNA was extracted from umbilical cord tissue and blood of calf born for confirming gene insertion. As determined by Southern hybridization, the transgene was not found.

Cryopreservation of mouse embryos biopsied at 4-cell stage was investigated by ultrarapid freezing. Four-cell embryos were obtained from ICR mice on 55h after hCG injection. Zona pellucida of the embryos were partially dissected with a cutting pipet, and then single blastomeres were biopsied from the embryos followed by incubation in + and +-free M16 medium for 30min. Biopsied embryos cultured for lh or 15h were frozen by ultrarapid freezing method using 3M DMSO or 5M glycerol as a cryoprotectant, respectively. The developmental rate of biopsied embryos after ultrarapid freezing and thawing to blastocysts was 81 % in the group of biopsied embryos cultured for lb and 98% in the group of biopsied embryos cultured for 15h, respectively. When biopsied embryos after ultrarapid freezing and thawing were transferred to the uteri of pseudopregnant recipients, normal live young were born. These results suggest that this freezing method can efficiently cryopreserve biopsied mouse embryos.

This study investigated full-term development potential of ultrarap idly frozen and thawed mouse 2-cell embryos. Mouse 2-cell embryos, dehydrated by exposure to freezing medium, were directly immersed into liquid nitrogen and thawed in 37 water. The embryos that were frozen and thawed were cultured in uitro and transferred to foster mothers to examine there developmental potential. As a result, the frozen-thawed 2-cell embryos developed to blastocysts in vitro as a similar rate as control 2-cell embryos did(in vitro 2-cell, 86.4%; in vivo 2-cell, 90.9%; solution control, 89.9%; control, 89.7%). Normal live young were obtained from transfer of frozen-thawed embryos to the oviduct and uterus of pseudopregnant recipients (3l.4~56.7%).

Plastics, such as fiber-reinforced plastics (FRP), from vessels, nets, ropes and buoys that are found in marine materials are refined by various factors in the ocean. These microplastics are present in the surface, middle, deep and sedimentary layers of the ocean depending on their physical and chemical properties. In this study, the distribution characteristics of microplastics in mud flats are investigated and their sources are estimated. The highest percentage of microplastics consisted of blue paint fragments, which seemed to be paint from a ship. In addition, many fibrous microplastics were found in the surface layer of the mud flats. These results suggest that low-density fibers are partially retained on the surface of mud flats during high and low tide. The differences in the amount and types of microplastics at the survey sites are considered to be influenced by the surrounding environment, such as fishing vessels and farms.

해양에서의 크기 5mm미만인 미세플라스틱은 선박･어업에 사용하는 도료, 타이어, 어망 등에서 발생한다. 이렇게 발생된 미세플라스틱은 우리나라 서남해안에 발달된 개펄에 침적할 것이며, 개펄에 침적된 미세플라스틱은 개펄 생태계에 영향을 미칠 것으로 사료된다. 본 연구에서는 김 양식장과 낙지 채취 개펄을 대상으로 깊이별로 미세플라스틱의 정성･정량 분석을 실시하였다. Table 1은 검출된 미세플라스틱의 결과이다. 김 양식장 인근의 개펄에 비해 낙지 채취 개펄에서 섬유상물질이 다량 검출되었고, 낙지 채취 개펄에 비해 김 양식장 인근의 개펄에서 비교적 많은 양의 타이어 분진이 검출되었다. 이와 같은 결과는 김 양식장과 낙지 채취 개펄에서의 생산활동의 차이에서 유래된 것으로 사료된다.

Limonium tetragonum is a halophyte grown naturally in the coastal region in South Korea. This study was conducted to investigate the effects of salt concentrations on seed germination, seedling growth, and antioxidant capacity of L. tetragonum. Seeds were collected from naturally grown plants of L. tetragonum and those at full maturity were used in this experiment. All experiments were performed at 0%, 0.5%, 1.0%, or 2.0% of salt concentrations. Seed germination rate was highest as 86% at 20℃ and followed as higher in order of 25℃, 30℃ and 15℃. The germination rate was about 80% at 0% or 0.5% of salt concentration, but it was very low at the salt concentrations higher than 1%. Growth of L. tetragonum seedlings showed no difference in Hoagland solution containing NaCl in the range of 0% to 1.0% and seedlings survived at 2.0% of NaCl concentration. As the salt concentration increased, the content of Na+ in the shoot increased, but that of K+, Ca++, or Mg++ decreased. The antioxidant activity and the content of total polyphenol and total flavonoid in the shoot were similar at 0% and 0.5% of NaCl and were highest at 2.0% of NaCl concentration. In conclusion, performance of seed germination and plant growth of L. tetragonum was highest at 0% and 0.5% of NaCl concentration, and showed no difference in antioxidant activity, total polyphenol contents, and total flavonoid contents at the same salt concentrations.

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℃ 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.

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.

This study was conducted to analyze seasonal and annual variations in rice quality and factors affecting the quality, for quality evaluation of the brand rice varieties produced in Jeonnam region. Coefficient of variation (CV) values for the seasonal variation in the rice quality were 3.1% in Toyo value, 2.1% in whiteness, 1.6% in protein content, 1.0% in moisture content, and 0.4% in head rice ratio. Quality characteristics of the brand rice varieties generally showed a decreasing tendency after April, as the months progressed. CV values for the annual variation in the rice quality were relatively high at 5.6% in protein content and 5.2% in Toyo value whereas those for whiteness and head rice ratio were relatively low, at 2.7% and 1.8%, respectively. Palatability and protein content showed high correlations with minimum air temperature, sunshine hours, rainfall, and daily temperature range. Head rice ratio had a negative correlation with daily temperature range whereas chalky rice ratio had a positive correlation with rainfall. Based on these results, we formulated a multiple regression equation to estimate palatability of cooked rice using protein content, whiteness, head rice ratio, and moisture content as follows:y ＝－6.71a ＋ 2.27b ＋ 1.29c ＋ 0.51d － 15.34 (R2=0.51*)(y: palatability of cooked rice, a: protein content, b: moisture content, c: whiteness, d: head rice ratio).

전 세계적으로 플라스틱의 사용량은 꾸준히 증가하고 있는 추세이다. 그 결과, 해양쓰레기 중 플라스틱의 비중은 60~80%로써 높은 비중을 차지하고 있다. 플라스틱 중에서도 미세플라스틱은 5mm 미만의 플라스틱 조각으로서 인위적으로 제조된 1차 미세플라스틱과 물리･화학적으로 인한 파쇄나 분해에 의한 2차 미세플라스틱으로 나눌 수 있다. 이러한 미세플라스틱은 생물증폭(Biomagnification)과 생물농축(Bioaccumulation)이 우려되고 있다. 최근 미세플라스틱의 관심이 대두되면서 미세플라스틱의 정량･정성분석에 대한 문헌이 증가하는 추세이지만, 정량에 사용하는 단위는 연구자마다 상이하여 상호 비교가 어려운 현실이다. 또한 시료의 상태에 따라 유기물분해, 밀도차선별을 선별적으로 적용해야 한다. 특정 환경매체에서 정량･정성분석의 결과는 배출원별 배출량과 함께 고려해야 한다. 국외의 경우 미세플라스틱의 배출원별 배출량에 관한 연구가 이미 진행되었으나, 우리나라의 경우 관련된 연구는 찾아볼 수 없다. 이에 본 연구에서는 국외 선행연구에서 사용한 기법을 적용하여 우리나라에서 배출되는 미세플라스틱의 양을 추정하였다. 그 결과, 1차 미세플라스틱 배출량이 2차 미세플라스틱 배출량보다 약 10배 많은 것으로 나타났다.

Anaerobic mesophilic batch tests of food waste and food waste leachate collected from food waste treatment facility were carried out to evaluate their ultimate biodegradability and two distinctive decay rate coefficients (k1 and k2) with their corresponding degradable substrate fractions (S1 and S2), respectively. Each 3 liter batch reactor was operated for more than 60 days at substrate to inoculum ratio (S/I) of 0.5 as an initial total volatile solids (TVS) mass basis. Result of Ultimate biodegradability of 74 ~ 83% for food waste and 85 ~ 90% for food waste leachate were obtained respectively. The readily biodegradable fraction of 85 ~ 93% (S1) of food waste Biodegradable Volatile Solids (BVS, So) degraded within the initial 15 days with a range of of 0.151 ~ 0.168 day−1, whereas the rest slowly biodegradable fraction (S2) of BVS degraded for more than 53 days with the long term batch decay rate coefficients of 0.009 ~ 0.010 day−1. For the food waste leachate, the readily biodegradable portion (S1) appeared to be 92 ~ 94% of BVS (So), which degrades with of 0.172 ~ 0.206 day−1 for an initial 15 days. Its corresponding long term batch decay rate coefficients were 0.005 ~ 0.009 day−1. It is recommended that the hydraulic retention times of mesophilic anaerobic digesters be 16 days for the food waste and 15 days for the food waste leachate, respectively. However a safety factor should be considered when designing a full scale plant.

Relationship between grain quality-related traits and daily mean temperature/sunshine hours during grain filling stage was analyzed using eleven high quality rice varieties at 24 experimental sites through eight provinces of Korea in 2013~2014. In the data set pooled across varieties, experimental sites and years, grain quality-related traits such as percentage of head rice (PHR), head rice yield (HRY), protein in milled rice (PRO) and Toyo Mido Meter glossiness value (TGV) were higher at the temperature lower than 22.6℃ for 40 days after flowering (DAF), which was optimum for percentage of grain filling in this study. Optimum sunshine hours for 40 DAF were 6.0~6.1 hr d -1 when considered PHR, HRY and TGV. PRO was associated with daily mean temperature and sunshine hours for 40 DAF in more varieties than the other traits. PRO was closely correlated with daily mean temperature during early filling stage and sunshine hours during early to mid filling stage, compared to other stages during grain filling. It is concluded that general trend in the variation of grain quality-related traits could be explained by the changes in daily mean temperature and sunshine hours during grain filling. In addition, climate conditions during early grain filling stage played important roles to enhance grain quality.