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Erick J. Núñez-vázquez - One of the best experts on this subject based on the ideXlab platform.

  • Allelopathic effect of Chattonella marina var. marina (Raphidophyceae) on Gymnodinium catenatum (Dinophycea)
    Harmful Algae, 2016
    Co-Authors: Leyberth J. Fernández-herrera, Christine J. Band-schmidt, David J. López-cortés, Claudia J. Hernández-guerrero, José J. Bustillos-guzmán, Erick J. Núñez-vázquez
    Abstract:

    Abstract The allelopathic effect of the raphidophyte Chattonella marina var. marina on the dinoflagellate Gymnodinium catenatum was determined. Both species are harmful algal bloom forming algae, produce toxic metabolites, and can co-exist in the environment. In general, raphidophytes tend to dominate over dinoflagellates, which may indicate an allelopathic effect of the former algae. Strains of C. marina var. marina and G. catenatum isolated from Bahia de La Paz were cultured in bi-algal cultures with and without cell contact. Additionally, cultures of G. catenatum were exposed to cell-free culture filtrates of the raphidophyte to test whether soluble allelopathic molecules are active. During late stationary phase, both species were cultivated in mixed cultures for 72 h using the following cell abundance proportions: 20 × 10 3  cells L −1 : 20 × 10 3  cells L −1 (1:1; G. catenatum : C . marina ); 10 × 10 3  cells L −1 : 20 × 10 3  cells L −1 (1:2), and 20 × 10 3  cells L −1 : 10 × 10 3  cells L −1 (2:1). Cells of G. catenatum were also exposed to different volumes of cell filtrates of C. marina (10, 20, and 50 mL) using the same cell abundance proportions for 24 h. Samples were taken daily for cell counts and microscopic observations. Growth inhibition was higher when there was cell contact between both species, however mortality of G. catenatum was also observed without direct cell contact, indicating that toxic metabolites are liberated to the culture medium. Changes in cell morphology of G. catenatum occurred in the presence of cells and filtrates of C. marina , such as loss of flagella and motility, swelling, loss of girdle and sulci, prominent nucleus, rupture of cell membrane, and cell lysis. Induction of temporary cysts was also observed. These results suggest that toxic metabolites are liberated to the medium by C. marina , affecting G. catenatum by inhibiting its growth and causing changes in its life history, providing new insights of interactions between raphidophytes and dinoflagellates that could happen in the natural environment when both species are present.

Wardhana Wisnu - One of the best experts on this subject based on the ideXlab platform.

  • SEBARAN SPASIAL SPESIES PENYEBAB HARMFUL ALGAL BLOOM (HAB) DI LOKASI BUDIDAYA KERANG HIJAU (Perna viridis) KAMAL MUARA, JAKARTA UTARA, PADA BULAN MEI 2011
    'Fakultas Perikanan dan Ilmu Kelautan Universitas Papua', 2012
    Co-Authors: - Mulyani, Widiarti Riani, Wardhana Wisnu
    Abstract:

    Telah dilakukan penelitian tentang sebaran spasial spesies HAB di lokasi budidaya kerang hijau (Perna viridis), Kamal Muara, Jakarta Utara pada bulan Mei 2011. Sampel diambil secara vertikal di sembilan stasiun dengan plankton-net.  Spesies HAB yang ditemukan berasal dari kelas Dinophyceae (Ceratium furca, Dinophysis caudata, Gonyaulax polygramma, Gonyaulax spinifera, Gymnodinium catenatum, Gymnodinium sanguineum, Prorocentrum micans, dan Prorocentrum sigmoides); Bacillariophyceae (Nitzschia spp., Chaetoceros spp., Skeletonema costatum, dan Thalassiosira spp.) dan Raphidophyceae (Chattonella spp.).  Berdasarkan peta isoplank diketahui bahwa sebaran terpadat pada bulan Mei 2011 adalah di stasiun dekat muara.   Kata kunci : Harmful Algal Blooms, Kamal Muara, kerang hijau, dan sebaran spasia

Wardhana W. - One of the best experts on this subject based on the ideXlab platform.

Leyberth J. Fernández-herrera - One of the best experts on this subject based on the ideXlab platform.

  • Cell Death and Metabolic Stress in Gymnodinium catenatum Induced by Allelopathy
    'MDPI AG', 2021
    Co-Authors: Leyberth J. Fernández-herrera, Christine J. Band-schmidt, Claudia J. Hernández-guerrero, Tania Zenteno-savín, Ignacio Leyva-valencia, Mauricio Muñoz-ochoa
    Abstract:

    Allelopathy between phytoplankton species can promote cellular stress and programmed cell death (PCD). The raphidophyte Chattonella marina var. marina, and the dinoflagellates Margalefidinium polykrikoides and Gymnodinium impudicum have allelopathic effects on Gymnodinium catenatum; however, the physiological mechanisms are unknown. We evaluated whether the allelopathic effect promotes cellular stress and activates PCD in G. catenatum. Cultures of G. catenatum were exposed to cell-free media of C. marina var. marina, M. polykrikoides and G. impudicum. The mortality, superoxide radical (O2●−) production, thiobarbituric acid reactive substances (TBARS) levels, superoxide dismutase (SOD) activity, protein content, and caspase-3 activity were quantified. Mortality (between 57 and 79%) was registered in G. catenatum after exposure to cell-free media of the three species. The maximal O2●− production occurred with C. marina var. marina cell-free media. The highest TBARS levels and SOD activity in G. catenatum were recorded with cell-free media from G. impudicum. The highest protein content was recorded with cell-free media from M. polykrikoides. All cell-free media caused an increase in the activity of caspase-3. These results indicate that the allelopathic effect in G. catenatum promotes cell stress and caspase-3 activation, as a signal for the induction of programmed cell death

  • Allelopathic effect of Chattonella marina var. marina (Raphidophyceae) on Gymnodinium catenatum (Dinophycea)
    Harmful Algae, 2016
    Co-Authors: Leyberth J. Fernández-herrera, Christine J. Band-schmidt, David J. López-cortés, Claudia J. Hernández-guerrero, José J. Bustillos-guzmán, Erick J. Núñez-vázquez
    Abstract:

    Abstract The allelopathic effect of the raphidophyte Chattonella marina var. marina on the dinoflagellate Gymnodinium catenatum was determined. Both species are harmful algal bloom forming algae, produce toxic metabolites, and can co-exist in the environment. In general, raphidophytes tend to dominate over dinoflagellates, which may indicate an allelopathic effect of the former algae. Strains of C. marina var. marina and G. catenatum isolated from Bahia de La Paz were cultured in bi-algal cultures with and without cell contact. Additionally, cultures of G. catenatum were exposed to cell-free culture filtrates of the raphidophyte to test whether soluble allelopathic molecules are active. During late stationary phase, both species were cultivated in mixed cultures for 72 h using the following cell abundance proportions: 20 × 10 3  cells L −1 : 20 × 10 3  cells L −1 (1:1; G. catenatum : C . marina ); 10 × 10 3  cells L −1 : 20 × 10 3  cells L −1 (1:2), and 20 × 10 3  cells L −1 : 10 × 10 3  cells L −1 (2:1). Cells of G. catenatum were also exposed to different volumes of cell filtrates of C. marina (10, 20, and 50 mL) using the same cell abundance proportions for 24 h. Samples were taken daily for cell counts and microscopic observations. Growth inhibition was higher when there was cell contact between both species, however mortality of G. catenatum was also observed without direct cell contact, indicating that toxic metabolites are liberated to the culture medium. Changes in cell morphology of G. catenatum occurred in the presence of cells and filtrates of C. marina , such as loss of flagella and motility, swelling, loss of girdle and sulci, prominent nucleus, rupture of cell membrane, and cell lysis. Induction of temporary cysts was also observed. These results suggest that toxic metabolites are liberated to the medium by C. marina , affecting G. catenatum by inhibiting its growth and causing changes in its life history, providing new insights of interactions between raphidophytes and dinoflagellates that could happen in the natural environment when both species are present.

Núñez-vázquez, Erick Julian - One of the best experts on this subject based on the ideXlab platform.

  • Co-ocurrencia de Chattonella marina y Gymnodinium catenatum en laBahía de LaPaz, Golfo de California (primavera2009)
    'Universidad Autonoma Metropolitana', 2017
    Co-Authors: López-cortés, David Javier, Band Schmidt, Christine Johanna, Gárate-lizárraga Ismael, Bustillos-guzmán, José Jesús, Hernández-sandoval, Francisco Eduardo, Núñez-vázquez, Erick Julian
    Abstract:

    During the period of 24 March to 14 May 2009, water and net samples were obtained for phytoplankton analyses; one aliquot was fixed in Lugol´s solution for species quantification and identification. Net samples were used for the identification of live phytoplankton species. Additionally, temperature in situ, chlorophyll a and inorganic nutrients were measured weekly in three stations. Two species were identified: Chattonella marina (Subrahmanyan) Y. Hara et Chihara and Gymnodinium catenatum Graham. Chattonella marina was the most abundant species with a density at subsurface level of 14 × 103 to 36 × 103 cell L-1 . Gymnodinium catenatum had densities were of 1 × 103 to 19 × 103 cell L-1 . Water column temperature was quasi homogeneous from surface to 20 m in depth, with an interval of 19.5 to 22.0 °C and 20.0 to 21.5 °C from March to April respectively. In the middle of May stratification of the water column initiated with a slight temperature difference of 5.0 °C recorded from surface to 20 m in depth. Nitrates varied from 0.5 to 11.0 µM and orthophosphates from 0.4 to 2.6 µM. Chlorophyll a showed a value at surface level of 7.5 mg m-3 and 3.5 mg m-3 at 20 m in March; in May chlorophyll a values ranged between 2.0 to 7.0 mg m-3 . We conclude that the presence of these two species during this study period was associated to the relaxation of the mixing processes in the zoneDurante el período del 24 de marzo al 14 de mayo de 2009 en la Bahía de La Paz, se obtuvieron muestras de agua y de red para análisis de fitoplancton. Una alícuota se fijó con una solución de Lugol para la identificación y cuantificación, la de red se utilizó para la identificación in vivo. Semanalmente se midió la temperatura in situ, se determinaron nutrientes inorgánicos y clorofila a en tres estaciones. Se identificaron dos especies: Chattonella marina (Subrahmanyan) Y. Hara et Chihara y Gymnodinium catenatum Graham. Chattonella marina fue la especie más abundante con densidades de 14 × 103 a 36 × 103 cél. L-1 a nivel sub-superficial. Gymnodinium catenatum se registró con densidades de 1 × 103 a 19 × 103 cél. L-1 . La temperatura del agua fue homogénea desde la superficie hasta los 20 m de profundidad, con un intervalo de 19.5 a 22.0 °C y de 20.0 a 21.5 °C a finales de marzo y abril respectivamente. En la primera mitad de mayo se inició la estratificación, con una diferencia térmica de 5.0 °C entre la superficie y los 20 m. Los nitratos variaron de 0.5 a 11.0 µM y los ortofosfatos de 0.4 a 2.6 µM. La clorofila a en marzo presentó un valor en superficie de 7.5 mg m-3 y a 20 m de 3.5 mg m-3 , en mayo varió de 2.0 a 7.0 mg m-3 . Se concluye que la aparición de las dos especies observadas en este estudio se asocia a la disminución de los procesos de mezcla en esta bahía

  • Co-ocurrencia de Chattonella marina y Gymnodinium catenatum en la Bahía de La Paz, Golfo de California (primavera 2009)
    Hidrobiológica, 2011
    Co-Authors: López-cortés, David Javier, Band Schmidt, Christine Johanna, Gárate-lizárraga Ismael, Bustillos-guzmán, José Jesús, Hernández-sandoval, Francisco Eduardo, Núñez-vázquez, Erick Julian
    Abstract:

    Durante el período del 24 de marzo al 14 de mayo de 2009 en la Bahía de La Paz, se obtuvieron muestras de agua y de red para análisis de fitoplancton. Una alícuota se fijó con una solución de Lugol para la identificación y cuantificación, la de red se utilizó para la identificación in vivo. Semanalmente se midió la temperatura in situ, se determinaron nutrientes inorgánicos y clorofila a en tres estaciones. Se identificaron dos especies: Chattonella marina (Subrahmanyan) Y.Hara et Chihara y Gymnodinium catenatum Graham. Chattonella marina fue la especie más abundante con densidades de 14 × 103 a 36 × 103 cél. L-1 a nivel sub-superficial. Gymnodinium catenatum se registró con densidades de 1 × 103 a 19 × 103 cél. L-1. La temperatura del agua fue homogénea desde la superficie hasta los 20 m de profundidad, con un intervalo de 19.5 a 22.0 °C y de 20.0 a 21.5 °C a finales de marzo y abril respectivamente. En la primera mitad de mayo se inició la estratificación, con una diferencia térmica de 5.0 °C entre la superficie y los 20 m. Los nitratos variaron de 0.5 a 11.0 μM y los ortofosfatos de 0.4 a 2.6 μM. La clorofila a en marzo presentó un valor en superficie de 7.5 mg m-3 y a 20 m de 3.5 mg m-3, en mayo varió de 2.0 a 7.0 mg m-3. Se concluye que la aparición de las dos especies observadas en este estudio se asocia a la disminución de los procesos de mezcla en esta bahía