Metatranscriptome Analysis of Margalefidinium polykrikoides Harmful Algal Bloom

Sang-Hyeok CHO,Yujin JEONG,Eunju LEE,Sangrak JIN,So-Ra KO,Seung Ho BAEK,Chi-Yong AHN,Hee-Mock OH,Byung-Kwan CHO,Suhyung CHO 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

Harmful algal bloom (HAB) is an abnormal algal outbreak occurring in various aquatic environments, destroying the marine industry and ecosystem and damaging humans through the food web. To control HAB, it is critical to understand both the intracellular changes of the bloom-forming algae and their interactions with the symbiotic organisms. Here, we analyzed the metatranscriptome of the HAB comprising Margalefidinium polykrikoides (formerly Cochlodinium polykrikoides) with other bloom-associated microorganisms. Our comprehensive analysis predicted that M. polykrikoides in the HAB preferred propagation through asexual replication rather than reductive reproduction for fast blooming. In particular, the combined transcriptomic expression patterns of increased transcription, translation, mitosis, and asexual division with the decreased meiotic cell cycle genes such as MEI2 were found. The transcriptome analysis of M. polykrikoides analysis also showed evidence of free ferric species exchange under HAB conditions. Through the metatranscriptome analysis during HABs, we analyzed the bacterial community co-habiting with M. polykrikoides during HAB and further suggested potential roles of bacteria such as mutualistic, opportunistic, or even algicidal interactions. Notably, the abundant bacterial species are responsible for ferric ion exchange with algae. Collectively, our results provide a genetic understanding of the bloom compromising algae and algal-bacterial interactions.

Algicidal effects of free-amine water-soluble chitosan to marine harmful algal species

Park, S.C.,Choi, C.,Jeong, G.W.,Lee, H.S.,Choi, S.J.,Kim, W.S.,Nah, J.W. Korean Society of Industrial and Engineering Chemi 2016 Journal of industrial and engineering chemistry Vol.34 No.-

<P>Harmful algal blooms (HABs) commonly cause significant damage to aquatic systems due to toxin production and depletion of oxygen. In this study, the low molecular weight water-soluble chitosan (LMWSC) was investigated as a new algicidal compound by first investigating the potential of LMWSC in selective combating HABs. The LMWSCs disrupted algal cell and chloroplast membranes within 1 h against HABs, leading to efflux of the intracellular components. For co-cultivation of harmful and harmless algal, LMWSC selectively kill the harmful algal. Based on these results, LMWSC is a promising novel material for harmful algal bloom control. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.</P>

Algicidal effects of free-amine water-soluble chitosan to marine harmful algal species

박성철,최창용,정경원,이현수,최선주,김원석,나재운 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.34 No.-

Harmful algal blooms (HABs) commonly cause significant damage to aquatic systems due to toxinproduction and depletion of oxygen. In this study, the low molecular weight water-soluble chitosan(LMWSC) was investigated as a new algicidal compound by first investigating the potential of LMWSC inselective combating HABs. The LMWSCs disrupted algal cell and chloroplast membranes within 1 hagainst HABs, leading to efflux of the intracellular components. For co-cultivation of harmful andharmless algal, LMWSC selectively kill the harmful algal. Based on these results, LMWSC is a promisingnovel material for harmful algal bloom control.

A novel method for cell counting of Microcystis colonies in water resources using a digital imaging flow cytometer and microscope

Jungsu Park,Yongje Kim,Minjae Kim,Woo Hyoung Lee 대한환경공학회 2019 Environmental Engineering Research Vol.24 No.3

Microcystis sp. is one of the most common harmful cyanobacteria that release toxic substances. Counting algal cells is often used for effective control of harmful algal blooms. However, Microcystis sp. is commonly observed as a colony, so counting individual cells is challenging, as it requires significant time and labor. It is urgent to develop an accurate, simple, and rapid method for counting algal cells for regulatory purposes, estimating the status of blooms, and practicing proper management of water resources. The flow cytometer and microscope (FlowCAM), which is a dynamic imaging particle analyzer, can provide a promising alternative for rapid and simple cell counting. However, there is no accurate method for counting individual cells within a Microcystis colony. Furthermore, cell counting based on two-dimensional images may yield inaccurate results and underestimate the number of algal cells in a colony. In this study, a three-dimensional cell counting approach using a novel model algorithm was developed for counting individual cells in a Microcystis colony using a FlowCAM. The developed model algorithm showed satisfactory performance for Microcystis sp. cell counting in water samples collected from two rivers, and can be used for algal management in fresh water systems.

An Algicidal Agent against Harmful Algae Using Novel N1-benzyl-N3, N3-diethylpropane-1,3-diamine Derivatives

Kang Seok Park,최두복,손형규,Young Cheol Chang,조훈 한국생물공학회 2023 Biotechnology and Bioprocess Engineering Vol.28 No.1

To develop a variety of algaecides for harmful algae control that cause water pollution, we synthesized a series of 79 derivatives based on the structure of N1- benzyl-N3, N3-diethylpropane-1,3-diamine and analyzed their structure-activity relationships toward a harmful and a harmless algal species. Among the derivatives, the best algicidal activities with LC50 values of 0.49 (compound 24) and 0.42 μM (compound 34) in Cyanobacteria, respectively were achieved when CH3 and F groups were substituted at the R2 position, with CH3CH3 group at the R3 position, and amine chain length 3 at the R4 position after fixing Cl substituent group at the R1 position of the benzaldehyde group. The compounds 24 and 34 decreased the chlorophyll content of treated groups by approximately 75-80% as compared to the control. Algicidal activities for harmful algal species were as follows, in the order of greatest to the least: Microcystis sp. > Microcystis aeruginosa > Hererocapsa circularisquama > Chattonella marina > Heterosigma akashiwo. The acute toxicities of compounds 24 and 34 against Daphnia magna showed EC50 values of 20.18 and 22.32 μM, respectively, which were approximately 46.4 and 44.69 times higher than the LC50 value against Microcystis sp., showing low ecotoxicity. In the case of Danio rerio, they showed very low ecotoxicity with EC50 values of 94.97 and 45.97 μM, respectively. These results indicate that compounds 24 and 34 could be potential agents for selectively controlling harmful algal blooms.

Characteristics of Photosynthetic Pigments during the Outbreak of Harmful Algal Bloom at the South Coastal Area in the Korean Sea Waters

( Sook Yang Kim ),( Woel Ae Lim ),( Young Sil Kang ) 한국환경생물학회 2010 환경생물 : 환경생물학회지 Vol.28 No.1

Cochlodinium polykrikoides has occurs regularly during the summer in the South Sea of Korea. To investigate photosynthetic pigments concerned with phytoplankton community structure as bloom of Cochlodinium polykrikoides, the experiment was sampled at 20 stations three times between July and September 2002 in the Southern Sea of Korea. The distribution of peridinin, the biomarker of dinoflagellate, was higher at the blooming time than it was before and it disappeared after bloom. The correlative coefficients between Chl. and peridinin at the blooming time and out of bloom were 0.9253 and 0.1613, respectively. This result indicated that the bloom was caused by dinoflagellate. The correlative coefficients between Chl. and fucoxanthin were 0.3282 and 0.9759, respectively, and the correlative coefficients showed the succession from dinoflagellate to diatom. This result means that the bloom of Cochlodinium polykrikoides can be detected by Chl. a information from satellite remote sensing. Therefore, if the algorithm to detect peridinin in addition to Chl. a were to be developed, dinoflagellate red tide could be monitored more effectively.

Effects of mycosubtilin homolog algicides from a marine bacterium, Bacillus sp. SY-1, against the harmful algal bloom species Cochlodinium polykrikoides

Jeong Seong-Yun,손홍주 한국미생물학회 2021 The journal of microbiology Vol.59 No.4

The marine bacterium, Bacillus sp. SY-1, produced algicidal compounds that are notably active against the bloom-forming alga Cochlodinium polykrikoides. We isolated three algicidal compounds and identified these as mycosubtilins with molecular weights of 1056, 1070, and 1084 (designated MS 1056, 1070, and 1084, respectively), based on amino acid analyses and 1H, 13C, and two-dimensional nuclear magnetic resonance spectroscopy, including 1H-15N heteronuclear multiple bond correlation analysis. MS 1056 contains a β- amino acid residue with an alkyl side chain of C15, which has not previously been seen in known mycosubtilin families. MS 1056, 1070, and 1084 showed algicidal activities against C. polykrikoides with 6-h LC50 values of 2.3 ± 0.4, 0.8 ± 0.2, and 0.6 ± 0.1 μg/ml, respectively. These compounds also showed significant algicidal activities against other harmful algal bloom species. In contrast, MS 1084 showed no significant growth inhibitory effects against other organisms, including bacteria and microalgae, although does inhibit the growth of some fungi and yeasts. These observations imply that the algicidal bacterium Bacillus sp. SY-1 and its algicidal compounds could play an important role in regulating the onset and development of harmful algal blooms in natural environments.

Alexandrium catenella와 유해성 적조종에 대한 Arthrobacter sp. NH-3와 살조물질의 살조능

정성윤 ( Seong Yun Jeong ),정남호 ( Nam Ho Jeoung ) 한국환경농학회 2015 한국환경농학회지 Vol.34 No.2

BACKGROUND: The aim of this study was to isolate and identify algicidal bacterium that tends to kill the toxic dinoflagellate Alexandrium catenella, and to determine the algicidal activity and algicidal range of algicide. METHODS AND RESULTS: Among of algicidal bacteria isolated in this study, NH-3 isolate was the strongest algicidal activity against A. catenella. NH-3 isolate was identified on the basis of biochemical characteristics and analysis of 16S rRNA gene sequences. The NH-3 isolate showed over 99% homology with Arthrobacter oxydans, and was designated as Arthrobacter sp. NH-3. The optimal culture conditions were 25℃, initial pH 7.0, and 2.0% (w/v) NaCl concentration. The algicidal activity of Arthrobacter sp. NH-3 was significantly increased to maximum value in the late of logarithmic phase. Arthrobacter sp. NH-3 showed algicidal activity through indirect attack, which excreted active substance into the culture filtrate. When 10% culture filtrate of NH-3 was applied to A. catenella, 100% of algal cells were destroyed within 30 h. In addition, the algicidal activities were increased in dose and time dependent manners. The pure algicide was isolated from the ethyl acetate extract of the culture filtrate of NH-3 by using silica gel column chromatography and high performance liquid chromatography (HPLC). We investigated the algicidal activity of this algicide on the growth of harmful algal bloom (HAB) species, including A. catenella. As a result, it showed algicidal activity against several HAB species at a concentration of 100 μg/mL and had a relatively wide host range. CONCLUSION: Taken together, our results suggest that Arthrobacter sp. NH-3 and its algicide could be a candidate for controlling of toxic and harmful algal blooms.

Isolation of marine algicidal bacteria from surface seawater and sediment samples associated with harmful algal blooms in Korea

실비아 그리스티안토,김재수,Kristyanto, Sylvia,Kim, Jaisoo The Microbiological Society of Korea 2016 미생물학회지 Vol.52 No.1

본 연구는 식물성플랑크톤의 대량증식 조절과 관련된 해양성 살조능이 있는 박테리아의 분리와 유해조류에 대한 분리 균주의 살조능 특성에 주로 초점을 맞추고 있다. 해수 표면에서 자연적으로 발생하는 유해조류번성(HAB)은 전세계적으로 많은 환경문제를 일으키고 있다. 본 연구에서는 유해조류 성장을 억제하는 능력을 가진 40개의 박테리아 균주를 마산만, 진해만, 돌섬, 거제도, 통영 앞바다에서 분리하였다. 분리된 균주들은 다양한 유해조류인 Cochlodinium polykrikoides, Chattonella marina, Skeletonema costatum, Heterosigma akashiwo, Heterocapsa triquetra, Prorocentrum minimum, Scrippsiella trochoidea에 대한 살조특성을 추가로 조사하였다. 살조균주의 선별은 이중층 아가배지와 현미경 계수법을 이용하여 진행하였고 Pseudomonas, Vibrio, Bacillus, Pseudoalteromonas, Ruegeria, Joostella, Marinomonas, Stakelama, Porphyrobacter, Albirhodobacter의 속들에 속하는 균주들이었다. 가장 중요한 유해조류인 Co. polykrikoides에 대한 가장 강력한 살조능은 10% 배양상등액으로 6시간 처리했을 때 94%를 보이는 균주였다. 이 연구를 통해 살조효과를 보이는 새로운 속으로 Marinomonas sp. M Jin 1-8, Stakelama sp. ZB Yeonmyeong 1-11 & 1-13, Porphyrobacter sp. M Yeonmyeong 2-22, Albirhodobacter sp. 6-R Jin 6-1를 새롭게 찾았다. 결론적으로 이들 해양박테리아를 이용하면 식물성플랑크톤 번성을 제어하는데 중요한 역할을 할 것으로 예상된다. This study mainly focused on isolation of marine algicidal bacteria associated with phytoplankton blooms and characterization of algicidal activity against harmful algae. Harmful algal blooms (HABs) found naturally in surface waters have caused many environmental problems worldwide. In this study, forty bacterial strains that have capability of inhibiting harmful algal growth were isolated from Masan Bay, Jinhae Bay, Dol Island, Jangmok Bay, and the Tongyeong Sea, Republic of Korea. The bacteria were screened furthermore for the characteristics on algicidal activities against Cochlodinium polykrikoides, Chattonella marina, Skeletonema costatum, Heterosigma akashiwo, Heterocapsa triquetra, Prorocentrum minimum, and Scrippsiella trochoidea. As a result, the algicidal bacteria that were screened from double over layer agar and microscopic counts tests belonged to genera Pseudomonas, Vibrio, Bacillus, Pseudoalteromonas, Ruegeria, Joostella, Marinomonas, Stakelama, Porphyrobacter, and Albirhodobacter. One of the most important HAB species is Co. polykrikoides and the strongest algicidal activity against the dinoflagellate was 94.00% after 6 h treatment with 10% bacterial culture filtrate. In this study, Marinomonas sp. M Jin 1-8, Stakelama sp. ZB Yeonmyeong 1-11 & 1-13, Porphyrobacter sp. M Yeonmyeong 2-22, and Albirhodobacter sp. 6-R Jin 6-1 were found to be as new genera of bacteria having anti-algal activity. These results suggest that these bacteria might play an important role in controlling phytoplankton blooms.

Inland harmful algal blooms (HABs) modeling using internet of things (IoT) system and deep learning

Do Hyuck Kwon,Seok Min Hong,Ather Abbas,JongCheol Pyo,Hyung-Kun Lee,Sang-Soo Baek,Kyung Hwa Cho 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.1

Harmful algal blooms (HABs) have been frequently occurred with releasing toxic substances, which typically lead to water quality degradation and health problems for humans and aquatic animals. Hence, accurate quantitative analysis and prediction of HABs should be implemented to detect, monitor, and manage severe algal blooms. However, the traditional monitoring required sufficient expense and labor while numerical models were restricted in terms of their ability to simulate the algae dynamic. To address the challenging issue, this study evaluates the applicability of deep learning to simulate chlorophyll-a (Chl-a) and phycocyanin (PC) with the internet of things (IoT) system. Our research adopted LSTM models for simulating Chl-a and PC. Among LSTM models, the attention LSTM model achieved superior performance by showing 0.84 and 2.35 (μg/L) of the correlation coefficient and root mean square error. Among preprocessing methods, the z-score method was selected as the optimal method to improve model performance. The attention mechanism highlighted the input data from July to October, indicating that this period was the most influential period to model output. Therefore, this study demonstrated that deep learning with IoT system has the potential to detect and quantify cyanobacteria, which can improve the eutrophication management schemes for freshwater reservoirs.