기후변화와 수산업의 도전

손재학 부산연구원 2012 부산발전포럼 Vol.- No.135

적조생물, Cochlodinium polykrikoides와 Gymnodinium sanguieum의 사멸에 있어 암모니아염의 효과

손재학,Sohn, Jae-Hak 한국생명과학회 2005 생명과학회지 Vol.15 No.4

Cell-free culture broth of marine halophilic bacterium, Kordia algicida was shown to possess specific algicidal ability against red tide organism, Cochlodinium polykrikides. Physiochemical characteristics of algicidal material originated in the bacterial culture broth were analyzed that its molecular weight was estimated to a 3,000 dalton and it was stable in heat and pH treatment. The algicidal fraction against C. polykrikoides obtained from gel permeable chromatography contained high concentration of ammonium ion as analyzed by ICP/Mass spectrum. C. polykrikoides by the fraction was quickly lysed within 1 min. It was shown that the effective concentration for algicide against C. polykrikoides was over 1mM of ammonium chloride. On the other hand, other metal ions presented in the algicidal fraction showed no algicidal effect against C. polykrikoides. In additon, ammonium ion exhibited species-specific killing spectrum for two species of red tide organisms, C. polykrikoides and Gymnodinium sanguieum. Therefore, further researches on the killing mechanism against C. polykrikoides exerted by ammonium ion, and subsequent development of replaceable algicidal materials will perform to provide useful tools for the control of red tide.

어촌관광, 어촌도 상품이다

손재학 한국해양수산개발원 2011 계간 해양수산 Vol.1 No.4

Effect of sex, hunger and relative body size on the use of ripple signals in the interactions among water striders Gerris latiabdominis

손재학,한창석,이상임,Piotr Grzegorz Jablonski 한국응용곤충학회 2014 Journal of Asia-Pacific Entomology Vol.17 No.4

Water striders use ripple signals in aggressive interactions between individuals for access to food. We askedwhether water striders produce ripple signals more frequently when they are hungrier and when the value offood resources is higher. We also asked if and how the use of signals depends on the size difference betweeninteracting individuals. We found that females used ripple signals more often than males did. The experimentsuggested that use of aggressive ripple signals is affected by hunger in females – the sex with high demandsfor food resources. Among females, but not males, we found out that the probability of using signals in responseto the approaching intruder depended both on the degree of hunger and on the size of the focal animal relative tothe size of the intruder. Before starvation, the probability of a female using a signal in an interaction with an intruderwashigherwhen the individual's sizewas larger relative to the intruder. After starvation, the focal individualsweremorelikely to signalwhen their sizewas smaller relative to the intruder. The results are consistentwiththe idea that these signals may reveal information about the signalers weight or hunger level, and specific hypothesesare suggested for the future studies.

호염성세균, Kordia algicida gen. nov., sp. nov.의 염류요구특성

손재학,Sohn Jae Hak 한국미생물학회 2005 미생물학회지 Vol.41 No.2

호염성세균인 Kordia algicida gen. nov,, sp. nov.은 규조류인 Skeletonema costatum에 의한 적조발생동안 마산만의 표층수로부터 분리되었다. 본 균주는 숙성해수가 공급된 ZoBell 2216e 배지에서 성장이 가능하나 $3\%$ NaCl만이 공급된 동 배지에서는 성장하지 않았다. 13종의 주된 재수성분을 대상으로 한 염류 요구성 조사에서 $Na^+,\;Mg^{2+}$ 및 $Ca^{2+}$ 이온이 제한된 배지에서는 성장을 하지 않아, 성장을 위해 필수적으로 3조의 이온을 요구하였다. 3종의 이온을 대상으로 한 Kinetic 조사에서 $Na^+,\;Ca^{2+}$ 및 $Mg^{2+}$ 의 Km 간은 각각 0.202 M, 0.089 mM, and 0.189 mM로 결정되었으며 $V_{max}({\mu}max)$는 또한 0.442h, 0.411h 및 0.316h로 결정되었다. 현미경적 관찰에서 K. algicida는 각 이온들을 제한하였을 때 $2\~8$시간에 내에 빠른 사멸을 나타내었다. 이러한 결과로 Kordia algicida는 해양으로부터 유래된 전형적인 호염성세균임을 알 수 있었으며 해양유래 미생물의 분리 시 각별한 주의가 요구됨을 시사한다. Moderately halophilic bacterium, Kordia algicida gen. nov., sp. novo was isolated from seawater of Masan Bay, Korea, during algal blooming caused by Skeletonema costatum. This bacterium was grown on the ZoBell 2216e medium supplied aged seawater, but not grown the medium supplied $3\%$ NaCl. This bacterium showed absolute requirements for mono and divalent cations such as $Na^+,\;Mg^{2+}\;and\;Ca^{2+}$, since no growth was observed in the medium, which is not supplemented with one of $Na^+,\;Mg^{2+}\;and\;Ca^{2+}$ ions. In kinetic studies for three kinds of cation, Km values of $Na^+,\;Ca^{2+}\;and\;Mg^{2+}$ were determined to 0.202 M, 0.089 mM, and 0.189 mM, respectively. Also, $V_{max}({\mu}max)$ was 0.442 h, 0.411 hand 0.316 h. The bacterial cells were quickly lysed in the condition limited by the cations. This result should be suggested that Kordia algicida originated from marine.

이슈진단 : 미국 서부 항만 노사분쟁 동향

손재학 한국해사문제연구소 2002 (月刊)海洋韓國 Vol.350 No.-

Environmental Factor Affecting the Distribution of Heterotrophic Bacteria and Chlorophyll a in Haengam and Masan Bay, Korea

손재학,안태영 한국해양환경·에너지학회 2000 한국해양환경공학회 학술대회논문집 Vol.2000 No.-

지속성 영양염제와 유분산제가 해변모래에 오염된 유류의 생분해에 미치는 영향

손재학,권개경,김상진 한국미생물학회 2003 미생물학회지 Vol.39 No.1

해변에 오염된 유류의 생분해를 증진시키기 위한 지속성 영양염제(Slow Release Fertilizer; SRE)와 유분산제 ($Corexit 9527^{R}$)의 처 리효과를 평가하기 위하여 2 회의 mesocosm실험을 실시하였다. 1 차 현장실험 에서 SRP처리구의 지방족 탄화수소분해율과 n-$C_{17}$/pristane, n-$C_{18}$/phytane비의 감소율은 시험 37일에 각각 85%,69%,61% 로 뚜렷한 생물정화 효과를 보였다. 반면에 $Corexit 9527^{R}$ 처리구에서 지방족 탄화수소의 분해율은 실험기간동안 56%로 대조구(50%)보다 뚜렷한 생물정화효과가 나타나지 않았으며 $Corexit 9527^{R}$과 n-$C_{18}$/phytane비의 감소율 또한 27%, 17%로 대조구(60%, 46%)보다 낮아 유류화합물의 생물정화가 오히려 억제되었다는 사실을 알 수 있었다. 그러나 2차 현장실험에서 SRF와 $Corexit 9527^{R}$을 함께 첨가한 처리구의 생물정화 결과는 지방족 탄화수소의 양, n-$C_{17}$/pristane과 n-$C_{18}$/phytane비의 변화를 관찰한 결과 억제효과는 크지 않았다. 이러한 결과로부터 유류유출시 영양물질의 첨가는 유류분해도를 향상시키는 반면,유분산제를 이용한 처리방법은 자연적인 생물정화기능을 오히려 억제 또는 제한하기 때문에 사용여부가 신중하게 고려되어야 함을 확인할 수 있었다. 따라서 유류오염사고 국가 긴급방제계획에 의한 유분산제의 대량 사용은 생물정화기술의 적용을 염두에 두고 재평가되어야 한다. To evaluate the effects of slow release fertilizer and chemical dispersant on oil biodegradation, mesocosm studies were conducted on sand seashore. The rapid removal rates (85%) of aliphatic hydrocarbons and the simultaneous decreases of n-$C_{17}$/pristane (69%) and $n-C_{18}/phytane$ (61%) ratios by the addition of slow-release fertilizer (SRF) within 37 days of experiment indicated that SRF could enhance the oil degrading activity of indigenous microorganisms in sand mesocosm. Although the growth of heterotrophic bacteria and petroleumdegrading bacteria in the mesocosm treated with $Corexit 9527^{R}$ was stimulated, the biological oil removal based on the ratios of $Corexit 9527^{R}$ and $n-C_{18}/phytane$ was inhibited. Removal rates of aliphatic hydrocarbons (56%), and n-$C_{17}$/pristane (27%) and $n-C_{18}/phytane$ (17%) ratios by the addition of chemical dispersant $Corexit 9527^{R}$ were similar or lower than those values of control (50, 60, 46%), respectively. The biodegradation activity, however, when simultaneously treated with SRF and $Corexit 9527^{R}$, was not highly inhibited and even recovered after the elimination of chemical dispersant. From these results it could be concluded that the addition of SRF enhanced the oil removal rate in oligotrophic sand seashore and chemical dispersant possibly inhibit the oil biodegradation. Hence, in order to prevent the unrestrained usage of chemical dispersant in natural environments contaminated with oil, the National Contingency Plan of Oil Spill Response should be carefully revised in consideration of the application for bioremedaition techniques.

수산물 수출 활성화를 위한 정책화 과정에 관한 연구

손재학(Jae-Hak SON),이상건(Sang-Gun LEE) 한국수산해양교육학회 2022 水産海洋敎育硏究 Vol.34 No.3

Evaluation of Petroleum Oil Degrading Mixed Microorganism Agent for the Bioremediation of Petroleum Oil Spilled in Marine Environments

손재학(Jae Hak Sohn) 한국생명과학회 2011 생명과학회지 Vol.21 No.11

유류분해에 있어 혼합미생물제제의 효과를 평가하기 위해 미생물제제의 처리성능과 microcosm test를 수행하였다. 유류분해세균은 0.5% Arabian heavy crude oil을 유일 탄소원으로 제공된 최소배지를 이용한 연속적인 농후배양을 통하여 분리하였다. 우수 유류분해 미생물조합인 3종의 균주(BS1, BS2, BS4)는 MSM배지에서 5일의 배양기간 동안 지방족 탄화수소를 48.4%, 방향족 탄화수소를 30.5% 생분해하였다. 처리성능 및 microcosm test는 Arabian heavy crude oil을 첨가한 후 3가지 처리조건인 무처리, 무기영양염처리 그리고 무기영양염 및 혼합미생물처리조건에서 유류화합물의 생물분해에 미치는 영향을 조사하였다. 무기영양염처리구와 무기영양염 및 혼합미생물처리구에서 지방족 탄화수소의 분해율은 실험기간 동안 유의하게 향상되었으며 두 실험구간 유의한 차이는 관찰되지 않았다. 그러나 무기영양염 및 혼합미생물처리구에서 방향족 탄화수소의 생분해율은 무기영양염제만을 처리한 시험구와 비교하여 처리성능 시험의 경우 50% 그리고 microcosm test의 경우 13%를 향상시켰다. 본 연구의 결과로부터 혼합미생물제제는 실험실, 처리성능 및 microcosm test에서 지방족뿐만 아니라 방향족 탄화수소의 생물분해를 촉진하였다. 특히 혼합미생물제제는 방향족 탄화수소의 제거를 위한 생물정화기술의 적용에 있어 유용한 도구로 판단된다. To evaluate the effects of microorganism agents on oil biodegradation, treatability and microcosm studies were conducted. Petroleum oil degrading bacteria were isolated from enriched cultures of oil-contaminated sediment samples using a mineral salts medium (MSM) containing 0.5% Arabian heavy crude oil as the sole carbon source. After a 5 day-incubation period using MSM, mixed micro-organisms of three species (strains BS1, BS2 and BS4) degraded 48.4% of aliphatic hydrocarbons and 30.5% of aromatic hydrocarbons. Treatability and microcosm tests were performed in the three different treatment conditions (AO: Arabian heavy crude oil, AO+IN: Arabian heavy crude oil+inorganic nutrient, AO+IN+MM: Arabian heavy crude oil+inorganic nutrient+mixed microorganism agents). Among these, significantly enhanced biodegradation of aliphatic hydrocarbons were observed in AO+IN and AO+IN+MM conditions, without showing any different biodegradation rates in either condition. However, the degradation rates of aromatic hydrocarbons in an AO+IN+MM condition were increased by 50% in the treatability test and by 13% in the microcosm test compared to those in an AO+IN condition. Taken together, it can be concluded that mixed microorganism agents enhance the biodegradation of aliphatic and aromatic hydrocarbons in laboratory, a treatability test, and a microcosm test. This agent could especially be a useful tool in the application of bioremediation for removal of aromatic hydrocarbons.