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Review of Anti-Leukemia Effects from Medicinal Plants (항 백혈병작용에 관련된 천연물의 자료조사)

  • Pae Hyun Ock;Lim Chang Kyung;Jang Seon Il;Han Dong Min;An Won Gun;Yoon Yoo Sik;Chon Byung Hun;Kim Won Sin;Yun Young Gab
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.3
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    • pp.605-610
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    • 2003
  • According to the Leukemia and Lymphoma Society, leukemia is a malignant disease (cancer) that originates in a cell in the marrow. It is characterized by the uncontrolled growth of developing marrow cells. There are two major classifications of leukemia: myelogenous or lymphocytic, which can each be acute or chronic. The terms myelogenous or lymphocytic denote the cell type involved. Thus, four major types of leukemia are: acute or chronic myelogenous leukemia and acute or chronic lymphocytic leukemia. Leukemia, lymphoma and myeloma are considered to be related cancers because they involve the uncontrolled growth of cells with similar functions and origins. The diseases result from an acquired (not inherited) genetic injury to the DNA of a single cell, which becomes abnormal (malignant) and multiplies continuously. In the United States, about 2,000 children and 27,000 adults are diagnosed each year with leukemia. Treatment for cancer may include one or more of the following: chemotherapy, radiation therapy, biological therapy, surgery and bone marrow transplantation. The most effective treatment for leukemia is chemotherapy, which may involve one or a combination of anticancer drugs that destroy cancer cells. Specific types of leukemia are sometimes treated with radiation therapy or biological therapy. Common side effects of most chemotherapy drugs include hair loss, nausea and vomiting, decreased blood counts and infections. Each type of leukemia is sensitive to different combinations of chemotherapy. Medications and length of treatment vary from person to person. Treatment time is usually from one to two years. During this time, your care is managed on an outpatient basis at M. D. Anderson Cancer Center or through your local doctor. Once your protocol is determined, you will receive more specific information about the drug(s) that Will be used to treat your leukemia. There are many factors that will determine the course of treatment, including age, general health, the specific type of leukemia, and also whether there has been previous treatment. there is considerable interest among basic and clinical researchers in novel drugs with activity against leukemia. the vast history of experience of traditional oriental medicine with medicinal plants may facilitate the identification of novel anti leukemic compounds. In the present investigation, we studied 31 kinds of anti leukemic medicinal plants, which its pharmacological action was already reported through many experimental articles and oriental medical book: 『pharmacological action and application of anticancer traditional chinese medicine』 In summary: Used leukemia cellline are HL60, HL-60, Jurkat, Molt-4 of human, and P388, L-1210, L615, L-210, EL-4 of mouse. 31 kinds of anti leukemic medicinal plants are Panax ginseng C.A Mey; Polygonum cuspidatum Sieb. et Zucc; Daphne genkwa Sieb. et Zucc; Aloe ferox Mill; Phorboc diester; Tripterygium wilfordii Hook .f.; Lycoris radiata (L Her)Herb; Atractylodes macrocephala Koidz; Lilium brownii F.E. Brown Var; Paeonia suffruticosa Andr.; Angelica sinensis (Oliv.) Diels; Asparagus cochinensis (Lour. )Merr; Isatis tinctoria L.; Leonurus heterophyllus Sweet; Phytolacca acinosa Roxb.; Trichosanthes kirilowii Maxim; Dioscorea opposita Thumb; Schisandra chinensis (Rurcz. )Baill.; Auium Sativum L; Isatis tinctoria, L; Ligustisum Chvanxiong Hort; Glycyrrhiza uralensis Fisch; Euphorbia Kansui Liou; Polygala tenuifolia Willd; Evodia rutaecarpa (Juss.) Benth; Chelidonium majus L; Rumax madaeo Mak; Sophora Subprostmousea Chunet T.ehen; Strychnos mux-vomical; Acanthopanax senticosus (Rupr.et Maxim.)Harms; Rubia cordifolia L. Anti leukemic compounds, which were isolated from medicinal plants are ginsenoside Ro, ginsenoside Rh2, Emodin, Yuanhuacine, Aleemodin, phorbocdiester, Triptolide, Homolycorine, Atractylol, Colchicnamile, Paeonol, Aspargus polysaccharide A.B.C.D, Indirubin, Leonunrine, Acinosohic acid, Trichosanthin, Ge 132, Schizandrin, allicin, Indirubin, cmdiumlactone chuanxiongol, 18A glycyrrhetic acid, Kansuiphorin A 13 oxyingenol Kansuiphorin B. These investigation suggest that it may be very useful for developing more effective anti leukemic new dregs from medicinal plants.

Effects of Brassica rapa SHI-RELATED SEQUENCE overexpression on petunia growth and development (배추 SHI-RELATED SEQUENCE 유전자 발현이 페튜니아 생장 발달에 미치는 영향)

  • Hong, Joon Ki;Suh, Eun Jung;Lee, Su Young;Song, Cheon Young;Lee, Seung Bum;Kim, Jin A;Lee, Soo In;Lee, Yeon-Hee
    • Journal of Plant Biotechnology
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    • v.42 no.3
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    • pp.204-214
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    • 2015
  • SHI-RELATED SEQUENCE (SRS) genes are plant-specific transcription factors that contain a zinc-binding RING finger motif, which play a critical role in plant growth and development. Among Brassica rapa SRS genes, BrSRS7 and BrLRP1 genes, isolated from shoot apical regions are important regulators of plant growth and development. In order to explore the function of BrSRS genes in horticultural plant growth and development, two constructs containing BrSRS7 and BrLRP1 under the control of a cauliflower mosaic virus 35S promoter were introduced into petunia by Agrobacterium-mediated transformation. The resulting transgenic plants were dwarf and compact plants with reduced plant height and diameter. Additionally, these transgenic plants had upward-curled leaves of narrow width and short internodes. Interestingly, the flower shapes of petunia were different among transgenic plants harboring different kinds of SRS genes. These phenotypes were stably inherited through generations $T_2$ and $T_3$. Semi-quantitative RT-PCR analyses of transgenic plants revealed that BrSRS7 and BrLRP1 regulate expression of gibberellin (GA)- and auxinrelated genes, PtAGL15- and PtIAMT1-related, involved in shoot morphogenesis. These results indicate that the overexpression of BrSRS7 and BrLRP1 genes suppressed the growth and development of petunia by regulating expression of GA- and auxin-related genes. From these data, we deduce that BrSRS7 and BrLRP1 genes play an important role in the regulation of plant growth and development in petunia. These findings suggest that transformation with the BrSRS genes can be applied to other species as a tool for growth retardation and modification of plant forms.

Human IL-27p28 Gene Polymorphisms are Associated with the Serum Total IgE Levels of Allergic Rhinitis Patients (사람의 IL-27p28 유전자 다형성은 알레르기성 비염 환자 혈청의 IgE 양과 연관됨)

  • Yu, Ji-In;Han, Weon-Cheol;Lee, Jae-Hoon;Kim, Hun-Soo;Yun, Ki-Jung;Lee, Jae-Hoon;Moon, Hyung-Bae;Chae, Soo-Cheon
    • Journal of Life Science
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    • v.19 no.3
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    • pp.299-304
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    • 2009
  • Interleukin 27 (IL-27) was discovered as a heterodimeric cytokine of the IL-12 family, and is composed of two subunits - Epstein-Barr virus induced gene 3 (EBI3) and p28. It acts as a versatile cytokine in the early regulation of Th1 initiation and in the negative regulation of the Th2 factor GATA binding protein 3 (GATA-3). This cytokine is mediated by the IL-27 receptor (WSX-1), which is highly expressed on $CD4^+$ T lymphocytes and NK cells. We previously identified four polymorphisms in the human IL-27p28 gene and suggested that the polymorphism of IL-27p28 is associated with susceptibility to asthma. To determine whether these IL-27p28 SNPs are associated with susceptibility to allergic rhinitis, the genotype and allele frequencies of IL-27p28 SNPs were analyzed between allergic rhinitis patients and healthy controls. Although the genotype and allele frequencies of IL-27p28 SNPs in allergic rhinitis patients were not significantly different from those of the control group, there was a suggestive difference (P=0.037) between these groups in total serum IgE levels in the g.2905T>G SNP of the IL-27p28 gene. Our result implies that the g.2905T>G SNP of the IL-27p28 gene might have an affect on IgE production in allergic rhinitis patients.

Anti-Inflammmatiry Effects of Nerium indicum Ethanol Extracts through Suppression of NF-kappaB Activation (NF-κB 활성 저해를 통한 협죽도 에탄올 추출물의 항염증 효능)

  • Kim, Tae-Hwan;Ko, Seog-Soon;Park, Cheol;Park, Sang-Eun;Hong, Sang-Hoon;Kim, Byung-Woo;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.20 no.8
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    • pp.1221-1229
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    • 2010
  • Nerium indicum, an India-Pakistan-originated shrub belonging to the oleander family, is reported to possess many pharmacological activities including cardiac muscle stimulation, and anti-diabetes, anti-angiogenesis, anti-cancer and neuro-protective activities. However, the anti-inflammatory properties of N. indicum were unclear. In this study, we investigated the effects of ethanol extract of the N. indicum leaf and stem (ENIL and ENIS) on the expression of anti-inflammatory mediators in U937 human pre-monocytic cell models. In U937 cells stimulated with phorbol 12-myristate-13-acetate (PMA), pre-treatment with ENIS significantly inhibited the expression of both cyclooxygenase-2 (COX-2) mRNA and protein, which are associated with inhibition of the release of prostaglandin $E_2\;(PGE_2)$, whereas the inhibitory effects appeared weakly in ENIL. Moreover, ENIS significantly attenuated PMA-induced IkappaB ($I{\kappa}B$) degradation and suppressed elevated nuclear factor kappa B (NF-${\kappa}B$) nuclear translocation. Taken together, these findings provide important new insights that N. indicum exhibits anti-inflammatory properties by suppressing the transcription of pro-inflammatory cytokine genes through the NF-kB signaling pathway.

Differences of Wood Vinegar Ingestion and Exercise Training on Blood Lipids, MDA, and SOD Activities in Rats (4주간 흰쥐의 목초액 섭취와 운동에 따른 혈중지질과 MDA, SOD 활성 차이)

  • Kang, Jong-Suk;Kim, Sea-Hyun;Kim, Pan-Gi;Lee, Dong-Woon;Ryu, Sung-Pil
    • Journal of Life Science
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    • v.19 no.9
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    • pp.1190-1199
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    • 2009
  • The purpose of this study is to identify the effects of exercise training and oak tree wood vinegar ingestion on the blood lipids and antioxidant activities of rats. The subjects were 28 Sprague Dawley male rats, and they were assigned into four groups (n=7, respectively): the control group (CON), the exercise group (EXE), the vinegar ingestion group (VIN), and the vinegar ingestion and exercise training group (VINEXE). The diet was based on high fat and oral administration of oak tree wood vinegar. The rats that were not given oak tree wood vinegar were given the same amount of distilled water orally in order to maintain the same level of stress. They were exercise trained on motor-driven treadmills during a four-week session. Weight changes in the VINEXE were significantly inhibited in the later period of exercise, when compared to the CON (p<0.05). Fat increase was significantly suppressed in VIN and EXE (p<0.05), and a synergistic effect was discovered in the VINEXE (p<0.05). Glucose and ammonia levels were significantly reduced in the EXE, VIN, and VINEXE compared to the CON (p<0.05). In blood lipids, TC and LDL-C were significantly enhanced in the EXE, VIN, and VINEXE compared to the CON (p<0.05), while HDL-C was significantly improved in the EXE and VINEXE (p<0.05). Liver MDA contents showed significant changes in each group (p<0.05), and SOD activities were significantly enhanced in the VIN and the VINEXE when compared to other groups (p<0.05). Therefore, oak tree wood vinegar ingestion with exercise training for four weeks may result in inhibition of weight gain, improvement of blood lipids, and inhibition of lipid peroxidation, contributing to health promotion.

Analysis of Telomere Length and Telomerase Activity of Tissues in Korean Native Chicken (한국 재래닭의 주령별 각 조직의 텔로미어 함량과 텔로머레이스 활성도 분석)

  • Jung G.S.;Cho E.J.;Choi D.S.;Lee M.J.;Park C.;Jeon I.S.;Sohn S.H.
    • Korean Journal of Poultry Science
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    • v.33 no.2
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    • pp.97-103
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    • 2006
  • Telomeres are essential for chromosome stability and are related with cell senescence, apoptosis and cancer. Even though telomere length and telomerase activity have been studied extensively, very little is known to analyze the telomere dynamics in chicken cells. This study was carried out to analyze the telomere distribution and telomerase activity of Korean Native Chicken cells along with aging. The cells were collected from brain, heart, liver, kidney and germinal tissues during physiological stages. Telomere distribution was analyzed by Quantitative-Fluorescence in situ Hybridization (Q-FISH) techniques using the chicken telomeric DNA probe. Telomerase activity was performed by Telomeric Repeat Amplification Protocol (TRAP) assay. In results, the telomeres of chicken were found at the ends of all chromosomes with the interstitial telomeres on chromosomes 1, 2 and 3. The amount of telomeres on chicken cells was decreased along with aging in most tissues. Furthermore, the telomere quantity was significantly different among tissues. The relative amount of telomeres in proliferous cells such as testis cells had much more than those of liver, brain, heart, blood and kidney cells. The telomerase activity was down-regulated in cells of brain, heart and liver tissues. Whereas gonadal cells showed a constitutive activity of telomerase during all stage of life. In conclusions, the telomere quantity and telomerase activity in chicken are closely relate to cell proliferation and tissue specificity during developmental stages and aging. There is also closely correlated between the amounts of telomeric DNA and telomerase activity in chicken tissues.

A Dual Lung Scan for the Evaluation of Pulmonary Function in Patients with Pulmonary Tuberculosis before and after Treatment (폐결핵치료전후(肺結核治療前後) 방사성동위원소(放射性同位元素)스캔에 의(依)한 폐기능(肺機能)의 비교(比較))

  • Rhee, Chong-Heon
    • The Korean Journal of Nuclear Medicine
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    • v.1 no.2
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    • pp.1-25
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    • 1967
  • In 20 normal cases and 39 pulmonary tuberculosis cases, regional pulmonary arterial blood flow measurements and lung perfusion scans by $^{131}I$-Macroaggregated albumin, lung inhalation scans by colloidal $^{198}Au$ and spirometries by respirometer were done at the Radiological Research Institute. The measured lung function tests were compared and the results were as the following: 1. The normal distribution of pulmonary blood flow was found to be $54.5{\pm}2.82%$ to the right lung and $45.5{\pm}2.39%$ to the left lung. The difference between the right and left pulmonary arterial blood flow was significant statistically (p<0.01). In the minimal pulmonary tuberculosis, the average distribution of pulmonary arterial blood flow was found to be $52.5{\pm}5.3%$ to the right lung and $47.5{\pm}1.0%$ to the left lung when the tuberculous lesion was in the right lung, and $56.2{\pm}4.4%$ to the right lung and $43.8{\pm}3.1%$ to the left lung when the tuberculous lesion was in the left lung. The difference of pulmonary arterial blood flow between the right and left lung was statistically not significant compared with the normal distribution. In the moderately advanced pulmonary tuberculosis, the average distripution of pulmonary arterial blood flow was found to be $26.9{\pm}13.9%$ to the right lung and $73.1{\pm}13.9%$ to the left lung when the tuberculous lesion was more severe in the right lung, and $79.6{\pm}12.8%$ to the right lung and $20.4{\pm}13.0%$ to the left lung when the tuberculous lesion was more severe in the left lung. These were found to be highly significant statistically compared with the normal distribution of pulmonary arterial blood flow (p<0.01). When both lungs were evenly involved, the average distribution of pulmonary arterial blood flow was found to be $49.5{\pm}8.01%$ to the right lung and $50.5{\pm}8.01%$ to the left lung. In the far advanced pulmonary tuberculosis, the average distribution of pulmonary arterial blood flow was found to be $18.5{\pm}11.6%$ to the right lung and $81.5{\pm}9.9%$ to the left lung when the tuberculous lesion was more severe in the right lung, and $78.2{\pm}8.9%$ to the right lung and $21.8{\pm}10.5%$ to the left lung when the tuberculous lesion was more severe in the left lung. These were found to be highly significant statistically compared with the normal distribution of pulmonary arterial blood flow (p<0.01). When both lungs were evenly involved the average distribution of pulmonary arterial blood flow was found to be $56.0{\pm}3.6%$ to the right lung and $44.0{\pm}3.2%$ to the left lung. 2. Lung perfusion scan by $^{131}I$-MAA in patients with pulmonary tuberculosis was as follows: a) In the pretreated minimal pulmonary tuberculosis, the decreased area of pulmonary arterial blood flow was corresponding to the chest roentgenogram, but the decrease of pulmonary arterial blood flow was more extensive than had been expected from the chest roentgenogram in the apparently healed minimal pulmonary tuberculosis. b) In the pretreated moderately advanced pulmonary tuberculosis, the decrease of pulmonary arterial blood flow to the diseased area was corresponding to the chest roentgenogram, but the decrease of pulmonary arterial blood flow was more extensive in the treated moderately advanced pulmonary tuberculosis as in the treated minimal pulmonary tuberculosis. c) Pulmonary arterial blood flow in the patients with far advanced pulmonary tuberculosis both before and after chemotherapy were almost similar to the chest roentgenogram. Especially the decrease of pulmonary arterial blood flow to the cavity was usually greater than had been expected from the chest roentgenogram. 3. Lung inhalation scan by colloidal $^{198}Au$ in patients with pulmonary tuberculosis was as follows: a) In the minimal pulmonary tuberculosis, lung inhalation scan showed almost similar decrease of radioactivity corresponding to the chest roentgenogram. b) In the moderately advanced pulmonary tuberculosis the decrease of radioactivity in the diseased area was partly corresponding to the chest roentgenogram in one hand and on the other hand the radioactivity was found to be normally distributed in stead of tuberculous lesion in the chest roentgenogram. c) In the far advanced pulmonary tuberculosis, lung inhalation scan showed almost similar decrease of radioactivity corresponding to the chest roentgenogram as in the minimal pulmonary tuberculosis. 4. From all these results, it was found that the characteristic finding in pulmonary tuberculosis was a decrease in pulmonary arterial blood flow to the diseased area and in general decrease of pulmonary arterial blood flow to the diseased area was more extensive than had been expected from the chest roentgenogram, especially in the treated group. Lung inhalation scan showed almost similar distribution of radioactivity corresponding to the chest roentgenogram in minimal and far advanced pulmonary tuberculosis, but there was a variability in the moderately advanced pulmonary tuberculosis. The measured values obtained from spirometry were parallel to the tuberculous lesion in chest roentgenogram.

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Biodistribution and Metabolism of I-123 Labelled Fatty Acid(I) : [I-123]15-(p-iodophenyl)pentadecanoic acid(IPPA) (I-123 표지 지방산의 체내 분포 및 대사(I) : [I-123]15-(p-iodophenyl)pentadecanoic acid(IPPA))

  • Chang, Young Soo;Lee, Dong Soo;Jeong, Jae Min;Suh, Yong-Sup;Chung, June-Key;Lee, Myung Chul;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.32 no.1
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    • pp.50-60
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    • 1998
  • I-123 labelled fatty acids are suitable for investigation of regional myocardial metabolism, so they are on the clinical trial. However, the precise properties of these materials are not characterized yet. We have synthesized phenylpentadecanoic acid and labeled this compound with I-123. The purpose of this study was to examine the stability, biodistribution, metabolism and SPECT imaging of [I-123]15-(p-iodophenyl)pentadecanoic acid(I-123-IPPA) that we made. The stability test of I-123-IPPA in serum of rat, mouse and human showed no free I-123 after 1 hour. In biodistribution study in mice for various time intervals after injection(5, 10, 15, 30, 60 minutes), uptake in myocardium was 14.5%ID/g(5 min), and 1.9%ID/heart(5 min), while uptake in muscles was 2.6%ID/g(5 min). Myocardium to blood ratio and myocardium to lung ratio increased for 5 min after injection and then decreased rapidly. Chromatographic data of rat blood and urine showed that little PPA was found in blood and urine at 15-20 min after injection. The myocardial I-123-IPPA SPECT images of a dog with myocardial infarction showed defects similar to those of Tc-99m-MIBI and F-18-FDG. These data suggest that I-123-IPPA is quite stable in vitro and shows favorable biodistribution in mice. SPECT imaging with I-123-IPPA demonstrated infarct zone as photon defect in dog model of myocardial infarction. I-123-IPPA may be used for the evaluation of fatty acid metabolism in clinical trials in Korea.

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Semi-daily Variations in Populations of the Dinoflagellates Dinophysis acuminata and Oxyphysis oxytoxoides and a Mixotrophic Ciliate Prey Mesodinium rubrum in Masan Bay (마산만에서 와편모류 Dinophysis acuminata 및 Oxyphysis oxytoxoides와 먹이생물 섬모류인 Mesodinium rubrum의 단주기적 개체군 변동)

  • KIM, SUNJU;YOON, JIHAE;KIM, MIRAN;PARK, MYUNG GIL
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.20 no.3
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    • pp.151-157
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    • 2015
  • Recent laboratory studies have documented that mixotrophic dinoflagellates Dinophysis spp. and heterotrophic dinoflagellate Oxyphysis oxytoxoides share a common prey, i.e. the mixotrophic ciliate Mesodinium rubrum. Nonetheless, very little is known about the population dynamics and species interactions among these protists in natural environments. To investigate the interactions between the dinoflagellate predators and their ciliate prey in the field, we took the samples twice a day from 26 July to 28 August, 2011 at a fixed station in Masan Bay and analyzed their abundances. During this study, salinity was highly variable, ranging from 5 to 28, due to the periodic input of rainfalls to the sampling station. Water temperature was on average $26.5^{\circ}C$ until 20 August and thereafter was about $21^{\circ}C$ by the end of the sampling period. The ciliate M. rubrum occurred persistently throughout the sampling period, ranging from 13 to $492\;cells\;mL^{-1}$. Cell densities of D. acuminata and O. oxytoxoides ranged from undetectable level to $19,833\;cells\;L^{-1}$ and from undetectable level to $100,333\;cells\;L^{-1}$, respectively. The high abundance of D. acuminata mostly followed the blooming of the ciliate M. rubrum, but it often did not peak even during heavy blooms of the prey, probably due to sensitivity to large salinity fluctuation and also presumably overlapped grazing by other mixotrophic dinoflagellates. The abundance of O. oxytoxoides was detected only when water temperature was lower than $24^{\circ}C$, indicating that water temperature is an important environmental factor to control the population dynamics of the dinoflagellate species.

Occurrence and Molecular Phylogenetic Characteristics of Benthic Sand-dwelling Dinoflagellates in the Intertidal Flat of Dongho, West Coast of Korea (서해안 동호 사질 조간대에 서식하는 저서성 와편모류의 출현양상 및 분자계통학적 특성)

  • KIM, SUNJU;YOON, JIHAE;PARK, MYUNG GIL
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.20 no.3
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    • pp.141-150
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    • 2015
  • Dinoflagellates are ubiquitous and important primary producers in the oceans. They have diverse trophic modes, i.e., phototrophic, heterotrophic, and mixotrophic modes and thereby, play important ecological role in marine microbial food-web. While many studies have been focused on planktonic dinoflagellates in pelagic ecosystems, benthic, sand-dwelling dinoflagellates that inhabit in intertidal zone have been very poorly documented worldwide. We investigated biodiversity, occurrence, and molecular phylogeny of benthic, sand-dwelling dinoflagellates from the intertidal flat of Dongho, west coast of Korea during low-tide, monthly from November 2012 to February 2014. About 27 species of 13 genera in orders Gonyaulacales, Gymnodiniales, Peridiniales, Prorocentrales have been identified, of which members in the genus Amphidinium constituted a major part of the sand-dwelling dinoflagellates in this area. A total of 34 isolates from 16 species of the sand-dwelling dinoflagellates were isolated from Dongho, Mohang, Gamami, and Songho in the west coast and Hyupjae in Jeju of Korea, their 28S rDNA sequences were successfully amplified, and applied for molecular phylogenetic analyses. In the 28S rDNA phylogeny, Amphidinium species diverged across three major clusters within the order Gymnodiniales and formed polyphyletic group. Based on the unambiguously aligned partial 28S rDNA sequences including variable D2 region, the genotypes of Amphidinium mootonorum Korean strains greatly differed from that of Canadian strain with 19.2% of pairwise nucleotide difference, suggesting that further ultrastructural studies may provide additional characters to clearly separate these genotypes. Two potential toxic species, Amphidinium carterae and A. operculatum appeared occasionally during this study. Quantitative assessment and toxicity of those species should be addressed in the future.