Cryptotympana atrata belongs to the family Cicadidae, has long been recognized as a damaging plant-sucking pest, and is distributed in East Asian countries. In addition, their cries cause direct harm to us through noise pollution and also reported twig damage in the forest environments. In this study, we isolated strains of the entomopathogenic fungus Metarhizium that occurred from C. atrata collected this year. Here, we provide the morphological character and molecular phylogenetic relationship of this species. This is the first record of the entomopathogenic fungus Metarhizium viridulum isolated from C. atrata in Korea and provides a candidate strain with potential use for biological agents.

양파 종자는 양파 생산을 위한 기초적 투입자원이기 때문에 건전한 종자는 양파 생산에서 매우 중요하다. 양파 종자에서 분리한 박테리아 중에서 양파 종자 발아를 억제하는 균주 OS1을 분리하였다. 분자 동정을 위해 16S rRNA 유전자 영역의 DNA를 분석하였고 이를 바탕으로 한 유연관계 분석을 통해 OS1 균주를 Leclercia adecarboxylata로 동정하였다. L. adecarboxylata는 면역 저하 환자 또는 기저 질환이 있는 환자에게 기회감염을 일으키는 것으로 알려져 있다. L. adecarboxylata OS1은 휘발 물질을 생산하고 이 휘발 물질이 양파 종자 발아를 억제하는 것으로 분석하였다. 특히, 양파 구근을 이용한 병원성 검정에서도 L. adecarboxylata OS1는 갈변증상과 썩음증상을 유발하였다. 아직 L. adecarboxylata에 의한 대규모 포장 또는 수확후병으로 인한 양파 피해사례가 보고된 적은 없지만, 이러한 결과는 L. adecarboxylata는 잠재적인 양파 병원체가 될 수 있음을 시사하고 양파 생산에 잠재적 위협 요소가 될 가능성을 보여준다. 또한, L. adecarboxylata는 인체 기회감염 병원체이기 때문에 양파로부터 언제든지 인체로 감염될 수 있는 위험성을 갖고 있다고 볼 수 있다.

토마토반점위조바이러스 (TSWV)는 고추, 토마토 등 경제적으로 중요한 작물에 심각한 피해를 주는 바이러스들 중 한 종이다. TSWV의 넓은 기주범위, 매개충인 총채벌레 방제의 어려움 및 TSWV의 효과적인 치료제가 없기 때문에, 저항성 품종을 사용하는 것이 TSWV를 예방하는 가장 효과적인 수단이 될 수 있다. 본 연구에서는 토마토에서 분리된 TSWV 분리주 (SW-TO2)의 유전학적·생물학적 특성을 구명하고, 최근에 국내에서 분리된 구기자, 머위, 당귀 TSWV 분리주와 비교하였다. 순수분리된 SW-TO2는 28 종의 지표식물 중 토마토를 포함한 17종에서 원형반점, 모자이크 증상 등 전신감염 증상을 보였다. SW-TO2의 유전자 계통분석 결과 국내에서 분리된 고추, 구기자 TSWV 분 리주와 98~99%의 상동성을 보이며 같은 그룹에 속하였다. TSWV 저항성 평가를 위한 생물검정법을 확립하고, 시판되고 있는 고추와 토마토 품종을 대상으로 4종의 TSWV 분리주에 대한 저항성 평가를 검정하였다. TSWV 저항성 평가는 첫째, 접종엽에 괴사반점 증상이 나타나거나 병징이 없는 경우, 둘째, 상엽에 병징이 없는 경우, 셋째, 상엽을 RT-PCR 진단한 결과 음성이 나왔을 경우 등 3가지 조건이 다 충족될 때 저항성으로 평가하였다.

Motile aeromonad septicaemia (MAS) mostly caused by Aeromonas hydrophila is a disease of high economic impact in freshwater organism. This study examined the seroconversion and seroprotection of formalinised local isolates of Aeromonas hydrophila in the Clarias gariepinus administered via different routes. Highly virulent Aeromonas hydrophila was treated with 40v/v formalin for 24 h. Bacterin was suspended to 0.5 McFarland standard and utilized to immunize Clarias gariepinus of 400±20 g in three groups with 50 samples each via three routes of administration. Antibody measurement taken at regular intervals before and after vaccination revealed a significantly higher antibody values in all routes compared to the control and difference was noticed at all intervals. Relative percent survival was 71.43, 62.86 and 57.14 intraperitoneal, intramuscular and immersion routes, respectively. Correlation analysis established a strong and direct relationship in the antibody generation through route of administration and efficacy of vaccine. This local vaccine was able to confer a high degree of immunity on Clarias gariepinus and can therefore be used to vaccinate against MAS.

식물성 대체식육 제조의 기초단계로 Soy protein isolate (SPI)를 이용한 dough의 물성학적 변화에서 CaCl2과 glucono-delta-lactone (GdL)에 의한 textural properties 영향에 대한 연구를 수행하였다. Soy protein isolate 20% (w/w) dough에 CaCl2 (0~2.0 g/100g) 또는 GdL (0~2.0 g/100g)을 첨가하여 90°C 30 min 열처리 후 textural profile analysis를 평가하였다. CaCl2 농도가 증가함에 따라 SPI dough의 hardness, gumminess, chewiness, cohesiveness, resilience가 점차 감소하였다. 반면 GdL 첨가에 의해서 hardness, gumminess, chewiness의 유의적 증가가 관찰되었고, cohesiveness, resilience가 약간 감소되었다. SPI dough의 springiness 변화에서 CaCl2 또는 GdL 첨가에 의한 영향이 없는 것으로 나타났다. 보수력 변화에서 CaCl2 1.5, 2.0 g/100g 첨가량에서 보수력의 유의적 감소가 관찰되었고, GdL 첨가량 0-2.0 g/100g 범위에서 보수력 변화는 관찰되지 않았다. Ca2+과 GdL은 protein coagulation에 영향을 미쳐서 SPI dough의 물성 변화가 유도된 것으로 사료되었다. 이를 근거로 향후 SPI를 이용한 식물성 대체식육 제조 시 anisotropic texture를 유도할 수 dough제조를 위한 기초 자료로 활용하고자 한다.

The objective of this study was to determine the effect of moisture content(45, 50, 55%), barrel temperature(140, 150°C), screw speed(150, 250 rpm) and two die configurations on the physical properties of extruded soy protein isolate(SPI). Water holding capacity(WHC), texture, integrity index and nitrogen solubility index(NSI) of extruded SPI were analyzed. The texture of extruded SPI was affected by the die configuration. The physical properties of extruded SPI was significantly influenced by barrel temperature, moisture content and die configuration. The increase in water injection rate and barrel temperature led to increase WHC and NSI. The higher water injection rate led to increase integrity index and texture(elasticity, cohesiveness, chewiness, cutting strength). The extruded SPI at 8 cm die configuration had higher integrity index than those of the 5 cm die configuration. Integrity index and NSI were negatively correlated. Thus, the die configuration can be useful to control quality of extruded SPI.

The objective of this study was to determine the effect of moisture contents (40, 50, 60%) and CO2 gas injection (0 and 800 mL/min) on physicochemical properties of extruded soy protein isolate (SPI). The expansion ratio and specific length at 40 and 50% moisture contents with CO2 gas injection increased while piece density decreased. On the contrary, the expansion ratio and specific length of extruded SPI at 60% moisture content with CO₂ gas injection decreased while piece density increased. Extruded SPI with CO2 gas injection had small cell size and higher amount of cell than extruded SPI without CO2 gas injection. The water holding capacity and nitrogen solubility index increased with CO2 gas injection increased while the integrity index and the springiness and cohesiveness decreased. In conclusion, extruded SPI with CO2 gas injection showed better expansion properties and cell formation than extruded SPI without CO2 gas injection.

Streptomyces species have been studied to find potent pest control agents as an alternatives to chemical insecticides.Previously, one of the ethyl acetate extract of Streptomyces isolates cultured on unpolished rice medium showed highlevel of juvenile hormone antagonist and larvicidal activities against pest insects including Aedes albopictus, Plutella xylostellaand Laodelphax striatellus. It has been known that the biosynthesis of secondary metabolites of Streptomyces could beinfluenced by a variety environments such as nutritional composition and growth conditions. In this study, to optimizeculture conditions for stable production of insecticidal compounds from this isolate, binding assay and bioassay-guidedmonitoring were conducted using various culture conditions.

The objective of this study was to determine the effect of moisture contents (40, 50, 60%) and CO2 gas injection (0 and 800 mL/min) on physicochemical properties of extruded soy protein isolate (SPI). The expansion ratio and the specific length increased, but piece density decreased with the increase in CO2 gas injection from 0 to 800 mL/ min at both 40 and 50% moisture contents. On the contrary, the expansion ratio and the specific length decreased, but piece density increased with the increase in CO2 gas injection from 0 to 800 mL/min at 60% moisture content. Extruded SPI with CO2 gas injection at 800 mL/min had small cell size and higher amount of cell than extruded SPI without CO2 gas injection. The water holding capacity and nitrogen solubility index increased, and the integrity index and the texture decreased with the increase in CO2 gas injection from 0 to 800 mL/min. In conclusion, extruded SPI with the CO2 gas injection at 800 mL/min showed better expansion properties and cell formation than extruded SPI without the CO2 gas injection.

The objective of this study was to determine the effect of moisture contents (40, 50, 60%) and CO2 gas injection (0 and 800 mL/min) on physicochemical properties of extruded soy protein isolate (SPI). The expansion ratio and the specific length increased, but piece density decreased with the increase in CO2 gas injection from 0 to 800 mL/ min at both 40 and 50% moisture contents. On the contrary, the expansion ratio and the specific length decreased, but piece density increased with the increase in CO2 gas injection from 0 to 800 mL/min at 60% moisture content. Extruded SPI with CO2 gas injection at 800 mL/min had small cell size and higher amount of cell than extruded SPI without CO2 gas injection. The water holding capacity and nitrogen solubility index increased, and the integrity index and the texture decreased with the increase in CO2 gas injection from 0 to 800 mL/min. In conclusion, extruded SPI with the CO2 gas injection at 800 mL/min showed better expansion properties and cell formation than extruded SPI without the CO2 gas injection.

The objectives of this investigation were to study the effects of moisture content, screw speed and barrel temperature on physical properties of extruded soy protein isolate (SPI) with L-cysteine and xylose. SPI with L-cysteine and xylose was extruded at 30 and 35% moisture contents, screw speed 150 and 250 rpm and barrel temperatures 140 and 160℃. SPI extruded at 30% moisture content, screw speed 250 rpm and barrel temperature 140℃ was control (100% SPI). Increasing barrel temperature and moisture content decreased expansion ratio of all extrudates but increasing screw speed increased expansion ratio. Moisture content, screw speed and barrel temperature affected the color (L, a, b, ΔE) of extrudates. Water absorption index (WAI) and fat binding capacity (FBC) increased with increasing barrel temperature and screw speed. WAI and FBC were the highest at 30% moisture content. The pore structure of extrudates was a finer at barrel temperature 160℃. The increase in screw speed and moisture content showed more organized fibrous and thicker cell walls. The extrusion condition and the addition of L-cysteine and xylose may improve physical properties such as the structure-forming and textures of extruded SPI products.