본 연구는 얼음결정체의 형성을 막고자 step-cooling 알고리즘을 적용하여 갈치를 과냉각 저장하였다. 저장의 신선도 유지효과를 확인하기 위해 냉장 및 냉동 저장된 갈치와의 신선도 비교평가를 실시하였다. 과냉각 저장은 냉장 저장과 비교하였을 때, 일반세균수와 단백질 부패로 인해 그 함량이 증가되는 VBN, TMA 값에서 비교적 작은 값을 보여 품질 유지에 효과를 나타내었다. 또한, 냉동 저장과 비교하였을 때, pH, VBN 및 TMA에서는 저장이 종료된 12일을 기준으로 차이를 크게 나타내지 않았다. 일반 세균수에서는 9일차까지 비슷한 값을 유지하였으며, 12일 차에서는 과냉각 시료가 높은 값을 보였다. 이를 통해, 과 냉각 저장이 미생물 생장을 최소화하고 단백질 부패를 지연시키는데 효과가 있다고 사료된다. 장기저장에서는 크게 영향을 미치지는 않았으나, 단기저장 관점에서는 냉장 저장보다 과냉각 저장이 갈치의 품질을 유지하는데 많은 장점을 가질 것으로 판단된다.

Behavioral response to a diel photoperiodicity (500 lx for 16 h, 5 lx for 4 h and < 0.5 lx for 4 h) and phototactic characteristics in dark conditions were examined with Siberian sturgeon Acipenser baerii (Chondrostei, Actinopterygii) prelarvae. Siberian sturgeon prelarvae represented both qualitative and quantitative changes in their behavioral patterns according to different light intensities in a diel photoperiodicity. Under daylight conditions (500 lx), prelarvae displayed saltatory changes of behavioral features with ages (Day 0-Day 9) in a general order of swimming-up/drifting, swimming in the upper water column, benthic swimming with rheotaxis, schooling and postschooling behavior. Compared to daylight conditions, prelarvae tended to show more benthic performances and quantitative reductions of schooling and postschooling behaviors under dimlight conditions (5 lx). Under dark conditions (< 0.5 lx), prelarvae exhibited a fairly uniform behavioral pattern characterized by the benthic swimming across the bottom of the tank. From phototaxis tests under dark conditions, navigational responses of prelarvae to a spotlight illumination were quantitatively changed as their ages increased. The phototactic responses reached the peak on Day 2, continued until Day 4, and then gradually decreased until Day 8. A partial recovery of positive phototaxis was observed on Day 9. Data from this study suggest that the diel light cycle as well as the light intensity of each interval in the cycle should be considered as important components of a practical guide for evaluating fitness and developmental states of artificially propagated Siberian sturgeon prelarvae.

Karyotype analysis is a major work in the process of triploid abalone production for the purpose of productivity and quality improvement. However, the metaphase spreads for karyotype analysis have been prepared just from the larvae at trochophore stage, which has restricted the spectrum of sample correction inhibiting more efficient analysis. Here, we investigated the feasibility of preparing metaphase spreads from the larvae at veliger stage that is the next developmental stage of trochophore. For this, diploid and triploid larvae at trochophore and veliger stages from Pacific abalone (Haliotis discus hannai ) were subjected to metaphase spread preparation and its efficiencies were measured and compared each other. As the results, although the efficiencies of metaphase spread preparation were significantly lower in the larvae at veliger stage compared to the ones at trochophore stage regardless of ploidy status, we found that the preparation of metaphase spreads, which showed the clear chromosomal images containing the normal number of chromosomes, was possible from the veliger stage larvae. On the other hands, all larvae used in this study regardless of developmental stage and ploidy did not show colchicine sensitivity. Moreover, no significant difference was observed in cell cycle distribution of the cells comprising larvae between two developmental stages regardless of ploidy status. These suggested that the details of protocol to prepare metaphase spreads from abalone larvae should be optimized depending on its developmental stages. Taken together, we demonstrated the feasibility of preparing metaphase spreads from H. discus hannai veliger stage larvae for karyotype analysis.

The development of drugs from natural plant sources is at growing interest due to the limitations of chemical drugs in terms of side effects and cost-effective factors of natural medicines. Among the various components contained in natural plant materials, flavonoids are of increasing interest because of their extended biological benefits. Flavonoids are classified into various types according to their structure and possess different activities depending on the structure. In this study, the flavonoids contained in Artemisia, native to Korea were examined and reviewed. HPLC chromatograms of three Artemisia species (Artemisia annua L., Artemisia iwayomogi and Artemisia argyi H.) were examined from published sources and their component analysis by MS data were summarized. The various flavonoids of Artemisia were classified into 12 types according to the main structure, and 10 flavonoids based on various activities were examined. The 10 flavonoids were identified as quercetin, kaempferol, rhamnetin, diosmetin, luteolin, methoxyflavone, catechin, apigenin, malvidin and genkwanin with extensive reported studies till date. The ten flavonoids examined have been reported to be effective in preventing and treating various diseases and exhibit activities such as anti-cancer, anti-inflammatory, antioxidant, antiviral, anti-obesity, anti-diabetic and anti-Alzheimer. The collective results from the reported studies suggest that the three types of Korean native Artemisia, contains various flavonoids with beneficial activities and may have therapeutic effects against diseases.