가막만 양식 참굴의 정장양상을 모델화 하기 위해 1997년 3월부터 1998년 5월가지 양식장에서 무작위 채집된 총 9,208개체의 각장 및 습중량을 조사하였으며, 참굴 양식장의 환경용량을 추정하기 위하여 1985년부터 2000년까지의 단위면적 당 생산량과 시설대수를 조사하였다. 참굴의 성장모델 추정에는 Bertalanlffy 성장식, 계절변동을 고려한 Bertalanffy 성장식과 일반화된 Schnute and Richards 성장식이 사용되었고, 환

This study was conducted to investigate cryopreservation of pearl oyster, Pinctada fucata martensii larvae. Four cooling rates (-0.25, -0.5, -0.75 and -1.0/min.) were used to examine a proper cooling rate during cryopreservation of trochophores before seeding temperature (-12). Seven developmental stages (early and late trochophores, early and late D-shaped larvae and early, middle and late umbo stage larvae) and different sugars (fructose, glucose and sucrose) were used to investigate optimal larval stage and effective sugar in cryopreservation of larvae. The survival rates of frozen-thawed trochophores increased at cooling rate of -1.0/min. As larval developing, survival rate of frozen-thawed larvae increased, except umbo stage larvae, and especially late D-shaped larvae highly survived as 91%. Addition of sugar revealed positive effect on cryopreservation in this experiment and 0.2 M glucose and sucrose mixed with 2.0 M dimethyl sulfoxide significantly enhanced survival rate of larvae (P<0.05). The results of our study indicate that desirable cooling rate, developmental stages of larvae and effective sugar far cryopreservation of pearl oyster, P. fucata martensii larvae are -1/min, late D-shaped larvae and 0.2 M glucose and sucrose, respectively.

느타리버섯 재비시 발생하여 피해를 일으키는 버섯해충류에 대한 조사 중 국내미기록종인 Megaselia tamiladuensis Disney(신칭: 버섯벼룩파리)가 동정되었다. 본 종의 분류학적 위치 및 형태적 특징을 기술하였다.

One hundred twenty five bacterial isolates were obtained from the brown blotch-diseased oyster mushrooms collected from markets. Among them, 45 were determined as pathogenic bacteria and white line foaming organisms(WLFO) were 6 strains and white line reaction organisms (WLRO) were 6 strains. All of the white line forming isolates were identified as Pseudomonas tolaasii which is a known pathogen of brown blotch disease of oyster mushroom by GC-MIS(Gas chromatography-microbial identification system). Six of the white line reacting organisms were identified as P. chlornraphis, P. fluorescens biotype A and type C. The rest of them were P. gingeri, P. agarici, P. fluorescens biotype B, P. chlororaphis, non-pathogenic P. tolaasii, P. putida biotype A and B etc. For spectnun of activity of tolaasin, culture filtrates from pathogenic isolates were examined by browning of mushroom tissue and pitting of mushroom caps. The weak pathogenic bacteria didn't induce browning or pitting of mushroom tissue. On the other hand, strong pathogenic isolates showed browning and pitting reaction on mushroom. An extracellular toxin produced by P. tolaasii, was investigated. The hemolysis activity test of 6 strains identified as P. tolaasii were 0.80.9 at 600 nm and 3 strains of WLRO were 0.9-1.0 and Pseudomonas spp. were 1.0-1.2. Observation of fresh mushroom tissue using confocal laser scanning microscopy was carried out for images of optical sectioning and vertical sectioning. Also images of brown blotch diseased oyster mushroom tissue after contamination P. tolaasii was obtained by CLSM.

긴수염버섯파리 (Lycoriella mali)에 대한 곤충병원성 선충 Steinernema carpocapsae 포천계통과 Heterorhabditis bacteriophora함양 계통의 병원성을 실내와 포장에서 실험하였다. 곤충병 원성 선충에 의한 긴수염버섯파리의 치사율은 선충의 종, 농도, 온도 및 긴수염버섯파리의 발육단 계에 따라 차이가 있었다. S. carpocapsae가 H. bacteriophora보다, 긴수염버섯파리 2령충보다는 3령충과 4령충에서 효과가 높았다. 그리고 온도에 따른 긴수염버섯파리의 치사율은 보다는 에서 높았다. 반수치사농도가 가장 낮았던 값은 에서 S. carpocapsae의 긴수염버섯파리 2령 충에서 20.0마리, 3령충에서 27.5마리였다. S. carpocapsae에 의한 긴수염버섯파리의 치사율은 알과 1령충을 제외한 전 발육단계에서 병원성이 높았으며, 가장 치사율이 높았던 것은 암컷 성충으로 2에서 74.0%, 에서 80.0%였다. S. carpocapsae는 긴수염버섯파리 암컷의 산란수를 감소시 켰고, 긴수염버섯파리의 성충에 의하여 감염이 된 후 전파가 되었다. 포장실험에서 S. carpocapsae를 당 마리로 처리한 14일째 유충감소율은 42.2%와 81.6%였으며 ,버섯재배사에서 곤충병원성 선충은 14일까지 지속되고 있었다. 곤충병원성 선충은 느타리버섯의 생장에는 아무런 영향을 미치지 않았다

The toxicity and toxin composition between blue mussel, Mytilus edulis and oyster, Crassostrea gigas collected at Woepori in Koˇ je island in South Coast of Korea in 1996 and 1997 were compared. The highest toxicity score was about 10 times higher in blue mussel than oyster (blue mussel, 8,670 ㎍; oyster, 860 ㎍ in 1996, blue mussel, 5,657 ㎍; oyster, 531 ㎍/100 g in 1997). The blue mussel also retained its toxicity for slightly longer period than oyster. In the both shellfish, PSP was composed almost exclusively of C toxins (C 1 and C2, 2065%) and gonyautoxins (GTX1, 2, 3 and 4, 38-78%). In the early period of toxin accumulation, the ratio of 11(3-epimer toxins (C2, GTX4) whose amount was 2556 mole% (5th March to 12th April in 1996) and 2580 mole% (18th March to 7th April in 1997), were higher than that of llα-epimer toxins (C1, GTX2) in both shellfish. As the lapse of intoxification time, however, the ratio of 11-epimer toxins (C1, GTX2) whose amount was 41-57 mole% (27th May to 3rd June in 1996) and 25-56 mole% (29th April to 12th May in 1997), became higher than that of 11-epimer toxins. The toxin compositions in the both samples changed on a daily basis, presumably owing to metabolism of the toxins in the bivalves.

Paralytic shellfish poison threatens public health most seriously from April to early May every year and gives adverse effects on export of these products. Major shellfish products exported were canned oyster, Crassostrea gigas and blue mussel, Mytilus edulis. Toxicities of canned shellfishes with toxin of low levels were mostly inactivated during the processing; in contrast, residual toxicity was of great concern with canned products from highly toxic shellfishes. This study was to provide basic data to establish food safety measure by evaluating the changes of toxicity during 2 year storage of canned products with toxic blue mussel and oyster. Any significant difference was not observed between two samples. Boiled can and smoked can showed inactivation of toxicity to some extent, whereas acidified can did not show reduction of toxicity even after 2 year storage. In case the initial toxicity of shellfish was high long term storage could not inactivate the toxicity of the canned product.

온도, pH및 염도 stress가 굴(Crassostrea gigas)의 malate dehydrogenase isozyme에 미치는 영향을 전기영동법으로 분석하였다. 대조군의 MDH isozyme은 2개의 band가 양극 쪽으로 이동되어 분리되었다. 각 실험 온도와 pH를 12시간 노출시킨 실험군에서는 1개의 band만 양극 쪽에서 분리되었고, 24시간과 48시간 노출한 실험군에서는 2개의 band가 모두 양극 쪽에서 분리되었다. 염분 농도가 5ppt

본 연구는 국내 느타리버섯 재배지에 발생하는 주요 버섯파리류를 조사하고, 이의 지역별.시기별 발생양상을 조사하였다. 버섯파리류 조사는 1997년 여름버섯재배기인 7~8월과 가을 버섯재배기인 10~11월의 2회에 걸쳐 전국 16곳의 주요 느타리버섯 재배지에서 실시하였다. 그 결과, 국내 느타리버섯 재배지에 발생하여 버섯에 피해를 가하는 버섯파리류로서 주용 3종인 Sciaridae, Cecidomyiidae 및 Scatopsidae 파리류를 포함하여 6종이 조사되었으며, 지역 및 시기에 따라 다소 차이가 있었다. 그중 Lycoriella mali(Diptera:Sciaridae)는 전국적으로 연중 발생하여 가장 문제시 되는 해충으로 조사되었다. 또 Coboldia fuscipes(Diptera:Scatopsidae)는 유충이 버섯균사를 가해하였으며, 주로 7~8월에 대량 발생한 후 가을에는 그 발생량이 감소하였다. 또한 유생생식을 하는 Mycophila sp. (Diptera:Cecidomyiidae)에 의한 균상 및 느타리버섯의 오염이 전국적으로 관찰되었는데, 특히 10~11월에 대량발생과 함께 그 피해가 극심하였다.

알루미나와 하소된 귤껍질의 소결반응에 의해 A I2 O3-CaO내화물이 제조되었다. 치밀화과정에서의 CaO의 영향과 A I2 O3-CaO 소결체의 특성을 고찰하였다. 소결체의 미세구조와 EDS 결과로 A I2 O3-CaO화합물을 확인하였다. 1450˚C에서 열처리한 소결체는 2.87/㎤의 부피비중과 12.03%의 겉보기 기공율을 가지며 압축강도는 312kg/cm2이였다. 1400˚C에서 서결체의 열팽창 계수는 6.55Kx10-6 K-1이였다.

To improve the environmental management and resources, in this study, we aimed to investigate the effect of adding oyster shell powder to Hanwoo manure on its characteristics and microbial composition during the storage period. Additives were deposited on top of the manure surface at the rate of 0, 0.5, and 1% of oyster shell powder per 200 g of Hanwoo manure in a plastic container with three replicates; however, untreated manure litter served as the control. Manure characteristics (dry matter, organic matter and crude ash) and microbial composition (lactic acid bacteria, yeast, Bacillus subtilis, Salmonella, and E.coli) were evaluated at day 0, 2, 4, and 8. Manure characteristics exhibited an effect on dry matter, organic matter, and crude ash at day 2 and 8 (p<0.05), and not for day 0 and 4 (p>0.05). With the exception of yeast content at day 4 of storage, lactic acid bacteria, yeast, Bacillus subtilis, Salmonella, and E.coli exhibited no significant differences in all conditions during the storage period. Conclusively, addition of 1% oyster shell powder to Hanwoo manure resulted in slightly better manure characteristics; however, its microbial composition remained unchanged.

To evaluate the remediation performance of recycled oyster shell powders to control nutrients release from polluted sediments. Different types of recycled oyster shell powder were applied on separated bottom sediments. The first type of oyster shell powder is Calcined Oyster Shell Powder (COSP) and another consist of ultrasonicated oyster shell powder (SOSP) which were composed of calcium peroxide. The recycled oyster shell powders were improving the water quality as slow oxygen releasing compound. The experimental results indicated that the Dissolved Oxygen (DO) in the treated columns were higher than the control column. pH was increased in the both experimental columns due to the hydrolysis of CaO2. Meanwhile, recycled oyster shell powders could prevent the nutrients (nitrogen and phosphorus) release from sediments into the overlying water. In addition, the total nitrogen and total phosphorus concentrations of the COSP applied column were decreased 27% and 20% compared to the control column respectively and the SOSP applied column were decreased 33% and 27% compared to control in the overlying water. It was proved that, COSP and SOSP can effectively adsorb phosphorus from sediments and prevent phosphorus release into overlying water from bottom sediments. In conclusion, COSP and SOSP applications was increased DO in the overlying water and nutrient released controlled effectively from the sediment.