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Vishnu Kiran Manam - One of the best experts on this subject based on the ideXlab platform.

  • biosynthesis and characterization of silver nanoparticles from marine macroscopic brown seaweed Colpomenia sinuosa mertens ex roth derbes and solier
    Social Science Research Network, 2020
    Co-Authors: Vishnu Kiran Manam
    Abstract:

    In the present study energy efficient, economically scalable colloidal silver (Ag) nanoparticles were biosynthesized from marine brown seaweed Colpomenia sinuosa by green synthesis method. The marine macroscopic brown seaweed Colpomenia sinuosa was used in the experimental study for the biosynthesis of silver nanoparticle since they are rich in phytochemicals, bioactive compounds and secondary metabolites which has reducing agents that may be environmentally acceptable and eco-friendly. The biosynthesized silver nanoparticles from marine macroscopic brown seaweed were characterized by UV-vis spectroscopy which confirmed the surface plasmon resonance of silver nanoparticles, Fourier transform infrared (FT-IR) spectroscopy to identify the presence of various functional groups in biomolecules responsible for the bio reduction of Ag+ and capping/stabilization of silver nanoparticles. X-ray diffraction (XRD) to observe face center cubic (fcc) and crystalline nature of silver nanoparticles, thermogravimetric analysis (TGA) which revealed the thermal stability and purity of the silver nanoparticles. Particle size distribution and morphology were investigated by scanning electron microscope (SEM) which showed silver nanoparticles in the size range of 54-85 nm. The particle distribution under different nanometers was analyzed using transmission electron microscopy (TEM).

  • biosynthesis and characterization of silver nanoparticles from marine seaweed Colpomenia sinuosa and its antifungal efficacy
    Social Science Research Network, 2020
    Co-Authors: Vishnu Kiran Manam
    Abstract:

    The present study illustrates the biosynthesis of colloidal silver nanoparticles (AgNPs) from marine seaweed Colpomenia sinuosa and their antifungal efficacy was determined against dermatophytic and non-dermatophytic fungi. The dermatophytic fungi used in this study are Microsporum nanum (ATCC 28951) and Trichophyton mentagrophytes (ATCC 28185) whereas the non dermatophytic fungi Aspergillus flavus (ATCC 20048) and Rhizopus microsporus (ATCC 22960). The rich content of phytochemicals, bioactive compounds and secondary metabolites in marine seaweed Colpomenia sinuosa possess the reducing/capping agents that may be environmentally acceptable and eco-friendly for the biosynthesis of silver nanoparticles. The efficacy of biosynthesized silver nanoparticles from marine macroscopic brown alga was performed using Kirby Bauer Method and the silver nanoparticles biosynthesized was characterized by UV-vis spectroscopy, Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD) and Thermo gravimetric analysis. Particle size distribution and morphology were investigated by scanning electron microscope which showed silver nanoparticles in the size range of 54-85 nm. The average size of the silver nanoparticle indicated by TEM analysis was found to be 34 nm. The antifungal efficacy of silver nanoparticles at the concentration 30 μg/mL revealed greater efficacy in dermatophytic fungi while Rhizopus microsporus as non dermatophytic fungus showed better antifungal activity when compared to the standard fungal antibiotics used.

  • biochemical investigation of marine seaweeds Colpomenia sinuosa and halymenia porphyroides collected along southeast coast of tamilnadu india
    Social Science Research Network, 2020
    Co-Authors: Vishnu Kiran Manam, Murugesan Subbaiah
    Abstract:

    In the current study the biochemical evaluation of the seaweeds were conducted which were collected along the south east coast of India. The marine brown macro alga Colpomenia sinuosa (Mertens ex Roth) Derbes and Solier as well as the marine red alga Halymenia poryphyroides Boergesen were used in this study. The relationship between the nutritive components and the variation of the biochemical composition like organic and inorganic constituents were mainly analyzed in the current study. The present analysis revealed that both the seaweeds were rich in protein content whereas more carbohydrate content was observed in marine red alga Halymenia porphyroides compared to the marine brown alga Colpomenia sinuosa. Similarly the analysis of inorganic biochemical constituents revealed that calcium, magnesium, iron and phosphorus were present in higher amount in marine brown alga Colpomenia sinuosa whereas sodium and potassium contents were observed in higher amount in marine red alga Halymenia porphyroides. The presence of high organic and inorganic biochemical constituents in these seaweeds may be of economic importance and ass potential health food for human diets.

  • phytochemical amino acid fatty acid and vitamin investigation of marine seaweeds Colpomenia sinuosa and halymenia porphyroides collected along southeast coast of tamilnadu india
    Social Science Research Network, 2020
    Co-Authors: Vishnu Kiran Manam, Murugesan Subbaiah
    Abstract:

    Seaweeds are marine macroscopic algae which are considered as the important living marine organisms with high nutritive value and rich bio-active compounds present in the ocean. In the current study the phytochemical, amino acid, fatty acid and vitamin profile analysis of the seaweeds were conducted which were collected along the south east coast of India. The marine brown macro alga Colpomenia sinuosa (Mertens ex Roth) Derbes and Solier as well as the marine red alga Halymenia poryphyroides Boergesen were used in this study. The relationship between the nutritive components and the variation between phytochemical, amino acid, fatty acid and vitamin profile were mainly analyzed in the current study. The present analysis revealed that phytochemical contents like alkaloids, triterpenoids, steroids and glycosides were present in higher amounts in marine red alga Halymenia porphyroides compared to the marine brown alga Colpomenia sinuosa. Similarly the amino acid analysis showed higher percentage in marine red alga Halymenia porphyroides when compared to the marine brown alga Colpomenia sinuosa. The fatty acid profile also revealed higher content in Halymenia porphyroides when compared to Colpomenia sinuosa. On the contrary the vitamin profile analysis revealed higher amounts of vitamins content in Colpomenia sinuosa rather than Halymenia porphyroides. The presence of high phytochemical, amino acid, fatty acid constituents in Halymenia porphyroides makes this seaweed more important when compared Colpomenia sinuosa which were rich in vitamin content and can be used as an important vitamin source for human and animal diet.

  • in vitro cytotoxic activity of silver nano particle biosynthesized from Colpomenia sinuosa and halymenia poryphyroides using dla and eac cell lines
    Social Science Research Network, 2014
    Co-Authors: Vishnu Kiran Manam
    Abstract:

    This study was conducted to investigate the invitro cytotoxic activity of silver nano particles biosynthesized from Colpomenia sinuosa and Halymenia poryphyroides using DLA and EAC cell lines by tryphan blue dye exclusion technique and MTT assay using Mouse L929 cell lines (Lungs fibroblast). The results of the trypan blue dye exclusion assay indicates that the silver nano particles biosynthesized from Colpomenia sinuosa and Halymenia poryphyroides inhibits the growth of DLA and EAC cell lines in a dose dependent manner against the standard drug Curcumin where the silver nano particle biosynthesized from Colpomenia sinuosa showed 61.57 % and silver nano particle biosynthesized from Halymenia poryphyroides showed 89.36 % in DLA cell line similarly the silver nano particle biosynthesized from Colpomenia sinuosa showed 81.96 % and silver nano particle biosynthesized from Halymenia poryphyroides 91.45 % in EAC cell line. The results of the MTT assay indicated the silver nano particles biosynthesized from Colpomenia sinuosa and Halymenia poryphyroides significantly inhibited the proliferation of L929 cells in dose dependent manner where the silver nano particle biosynthesized from Colpomenia sinuosa showed 37.06 % and silver nano particle biosynthesized from Halymenia poryphyroides showed 100 % against the standard drug Curcumin.

S Murugesan - One of the best experts on this subject based on the ideXlab platform.

  • invitro antioxidant activity of silver nano particles from Colpomenia sinuosa and halymenia poryphyroides
    Social Science Research Network, 2014
    Co-Authors: Vishnu Kiran Manam, S Murugesan
    Abstract:

    This study was conducted to investigate the in-vitro antioxidant activities of silver nano particles biosynthesized from Colpomenia sinuosa and Halymenia poryphyroides. The free radical scavenging activity of the extracts was measured by DPPH and ABTS and the antioxidant potential were compared with commercial antioxidants, such as Butylated Hydroxy Toulene (BHT) and L- ascorbic acid. The antioxidant activity of experimental algae showed a dose dependent increase when compared to commercial antioxidants. Spectrophotometric determination of the active compounds revealed that the antioxidant activity might be attributed to algal contents of carotenoids, free phenols and fatty acids.

  • biosynthesis of silver nanoparticles from marine alga Colpomenia sinuosa and its antibacterial efficacy
    Social Science Research Network, 2014
    Co-Authors: Vishnu Kiran Manam, S Murugesan
    Abstract:

    Silver nano particles are known to be good antibiotic agents. In this study biosynthesis of silver (Ag) nano particles of marine alga Colpomenia sinuosa were obtained by green synthesis method and their efficacy was studied against Gram-positive and Gram-negative bacteria. The efficacy was performed using Kirby Bauer Method and MIC, MBC were also determined. The extra cellular mechanism of silver nano particle formation was characterized by UV-vis spectroscopy, Fourier Transform Infrared (FT-IR) Spectroscopy-ray Diffraction (XRD), and Scanning Electron Microscopic (SEM) study showed the formation of silver nano particle in the range of 54-65 nm in size. Silver nanoparticles showed greater efficacy towards Gram-positive and Gram-negative microorganisms compared to the standard antibiotics.

  • biological synthesis of silver nanoparticles from marine alga Colpomenia sinuosa and its in vitro anti diabetic activity
    Social Science Research Network, 2014
    Co-Authors: Vishnu Kiran Manam, S Murugesan
    Abstract:

    Diabetes is a clinical syndrome characterized by hyperglycemia due to absolute or relative deficiency of insulin. The intestinal digestive enzymes alpha glucosidase and alpha amylase plays a key role in carbohydrate digestion, one main anti-diabetic approach is to reduce the post prandial glucose level in blood by inhibition of α-glucosidase and α-amylase enzymes. The synthesis of silver nanoparticles is an active area of application research in nanotechnology. Biological means by using plants, algae, fungi, bacteria are been employed for the production of low-cost, energy efficient, and non-toxic silver nanoparticles. Silver nanoparticles were prepared from marine alga Colpomenia sinuosa by green synthesis method and the characterization were determined using various techniques like UV – Nano photometer, XRD, FT-IR and SEM. In the present study antidiabetic activity was studied from the biosynthesis of silver nanoparticles from the marine brown alga Colpomenia sinuosa. The assay results of silver nanoparticles showed dose dependent significantly (P<0.005) increase in percentage inhibitory activity against α–amylase and α–glucosidase enzymes.

Bitencourt, Marisa Dantas - One of the best experts on this subject based on the ideXlab platform.

  • Análise do potencial do sensoriamento remoto orbital na identificação de macroalgas marinhas bentônicas
    Foz do Iguaçu, 2013
    Co-Authors: Nascimento, Edisa Ferreira Inocêncio, Lopes Filho, Euro Silva, Bitencourt, Marisa Dantas
    Abstract:

    Benthic algal cover and trends in its changes are indicators of water state in coastal areas. Mapping benthic algal\ud cover with conventional methods (scuba diving) provides great accuracy and high resolution yet is very\ud expensive and time consuming. Due to the recent global changes, several parts of the Brazilian coast may be\ud impacted jeopardizing benthic macroalgal ecosystems. Mapping that benthic macroalgal cover by remote sensing\ud can significantly improve the decision making. However, it is required certain knowledge about the optical\ud signatures of different bottom types. To use remote sensing properly, it is necessary to build a spectral library of\ud the most common macroalgae found within the Brazilian coast. Thus, using a spectroradiometer in the field, in\ud several Brazilian beaches, the reflectances were measured for red, green, and brown macroalgae, seagrass, sand,\ud pebble, and wet and dry decaying mats of macroalgae and higher plants. That field data were organized toward\ud the optical spectral bands found in the MERIS satellite and analyzed looking for the best index to represent each\ud group (red, green and brown). The index 7/5 (similar to MERIS bands) separated the green algaes (Caulerpa\ud racemosa = 0,76, ± 0,12; Ulva sp. = 0,42, ± 0,17), from red algaes (Hypnea musciformis = 1,29, ± 0,20;\ud Acanthophora spicifera = 1,24, ± 0,21), but not from brown algaes (Padina gymnospora = 0,84, ± 0,28;\ud Colpomenia sinuosa = 0,88, ± 0,32)

  • Análise do potencial do sensoriamento remoto orbital na identificação de macroalgas marinhas bentônicas
    Instituto Nacional de Pesquisas Espaciais (INPE), 2013
    Co-Authors: Nascimento, Edisa Ferreira Inocêncio, Lopes Filho, Euro Silva, Bitencourt, Marisa Dantas
    Abstract:

    Benthic algal cover and trends in its changes are indicators of water state in coastal areas. Mapping benthic algal cover with conventional methods (scuba diving) provides great accuracy and high resolution yet is very expensive and time consuming. Due to the recent global changes, several parts of the Brazilian coast may be impacted jeopardizing benthic macroalgal ecosystems. Mapping that benthic macroalgal cover by remote sensing can significantly improve the decision making. However, it is required certain knowledge about the optical signatures of different bottom types. To use remote sensing properly, it is necessary to build a spectral library of the most common macroalgae found within the Brazilian coast. Thus, using a spectroradiometer in the field, in several Brazilian beaches, the reflectances were measured for red, green, and brown macroalgae, seagrass, sand, pebble, and wet and dry decaying mats of macroalgae and higher plants. That field data were organized toward the optical spectral bands found in the MERIS satellite and analyzed looking for the best index to represent each group (red, green and brown). The index 7/5 (similar to MERIS bands) separated the green algaes (Caulerpa racemosa = 0,76, \ub1 0,12; Ulva sp. = 0,42, \ub1 0,17), from red algaes (Hypnea musciformis = 1,29, \ub1 0,20; Acanthophora spicifera = 1,24, \ub1 0,21), but not from brown algaes (Padina gymnospora = 0,84, \ub1 0,28; Colpomenia sinuosa = 0,88, \ub1 0,32). Palavras chave: sensoriamento remoto, macroalgas, remote sensing.Pages: 8845-885

Robert L Fletcher - One of the best experts on this subject based on the ideXlab platform.

  • life history of Colpomenia sinuosa scytosiphonaceae phaeophyceae in the azores
    Journal of Phycology, 2003
    Co-Authors: Marisa F Toste, Ana I. Neto, Manuela I Parente, Robert L Fletcher
    Abstract:

    Colpomenia sinuosa (Mertens ex Roth) Derbesa nd Solier (Scytosiphonaceae, Phaeophyceae) is a com- mon species on the rocky intertidal shores of the Azores, where reproductive gametophytes occur throughout the year. Life-history studies of this species were carried out in culture, and both sexual and asexual reproduction were observed. Anisoga- mous gametes fused to form zygotes. The zygotes gave rise to a filamentous prostrate sporophyte gene- ration bearing unilocular sporangia, under both short-day and long-day conditions at 15 and 221 C, and to both unilocular and plurilocular sporangia, under the lower temperature condition. Unispores developed into gametophytes, and plurispores gave rise to filamentous sporophytes. Asexual reproduc- tion was carried out by unfused female gametes and asexual plurispores produced from the same game- tophyte. Unfused gametes developed into filamen- tous prostrate sporophytes producing unilocular sporangia in both culture conditions, and unispores released from the sporangia gave rise to gameto- phytes. Asexual plurispores from field gameto- phytes, under both culture conditions, developed directly into new gametophytes. The species ex- hibited three types of life history: a heteromorphic, diplohaplontic; a heteromorphic, monophasic (both with alternation between the erect and filamentous prostrate thalli); and a monomorphic, monophasic.

Muñoz Ochoa Mauricio - One of the best experts on this subject based on the ideXlab platform.

  • Potencial farmacológico de algas marinas de Baja California Sur, México
    Instituto Politécnico Nacional (IPN), 2016
    Co-Authors: Muñoz Ochoa Mauricio
    Abstract:

    En este trabajo se estudiaron los extractos etanólicos de 62 especies de algas recolectadas a lo largo de la península de Baja California Sur, México, por su potencial como fuente de compuestos bioactivos. La actividad antibacteriana, antioxidante, citotóxica, anti-bioincrustante e inhibitoria de los mecanismo de resistencia bacteriana a los antibióticos fueron las actividades evaluadas en este trabajo de tesis. La primera parte de la tesis se centra en la identificación de las algas más prometedoras como fuente de compuestos con activos contra bacterias patógenas resistentes a antibióticos [Staphylococcus aureus (ATCC BAA-42), Streptococcus pyogenes (ATCC BAA-946) y Escherichia coli (ATCC BAA-196)] con mecanismos de resistencia conocido, así mismo, contra Mycobacterium tuberculosis, los extractos activos contra el M. tuberculosis se analizaron por su actividad citotóxica contra la línea celular VERO. También, la primera parte comprende un estudio de selección de los extractos activos frente a microorganismos causantes de la bioincrustación en superficies sumergidas en agua (3 microorganismos terrestres, tres marinos y 3 microalgas). Los resultados más relevantes en cuanto al efecto de los extractos como inhibidores de los mecanismo de resistencia bacteriana, de los 62 extractos etanólicos probados, 12 (20%) de ellos en combinación con la ampicilina fueron capaces de revertir la resistencia de S. aureus y 8 (13%) con eritromicina la de S. pyogenes. El extracto de Sargassum horridum (04-003) fue el único que revirtió la resistencia de S. aureus y S. pyogenes a la ampicilina y eritromicina, respectivamente. Adicionalmente el 80% de los extractos fueron activos contra al menos uno de los microorganismos de prueba y el 51% contra dos microorganismos probados. En el ensayo contra M. tuberculosis solo 5 (8%) extractos mostraron actividad: Laurencia johnstonii (04-005) con una CMI = 12.5 g mL-1, 3.13g mL-1 para Laurencia sp., S. horridum (04-003), Pterosiphonia bipinnata (07-003) y Laurencia pacifica con una CMI = 6.25 g mL-1. Las CMI de estos extractos en las pruebas de citotoxicidad fueron 19.05g mL-1 para S. horridum, < 2 g mL-1 para L. johnstonii y Laurencia sp., 26.77 g mL-1 para L. pacifica y 30.76 g mL-1 para P. bipinnata. En los ensayos de actividad anti-bioincrustrante, 54 extractos fueron evaluados por su capacidad para inhibir el crecimiento de un grupo de microorganismos formadores de incrustraciones, entre llos: E. coli (ATCC 23176), Enterobacter aerogenes (ATCC 13048), S. aureus (ATCC 25923), Pseudoalteromonas elyakovii (ATCC 700519), Polaribacter irgensii (ATCC 700398) Vibrio aestuarianus (ATCC 35048), Fragilaria crotonensis, Scenedesmus armatus y Cosmarium sp. La concentración mínima inhibitoria (CMI) de todos los extractos activos se encontró en el rango de 0,1 a 50 g mL-1. De todos los extractos probados, 4 (7.4%) fueron activos contra E. coli, 9 (16.6%) activos contra E. aerogenes, 3 (5.5%) activos frente a S. aureus, 5 (9.2%) frente a P. ingensii, 7 (12.9%) contra P. elyakovii y 43 (79.6%) frente a V. aestuarianus. Padina mexicana y U. dactylifera fueron las más activas frente a E. coli con una CMI = 1.0 g mL-1, los extractos de Gelidium robustum, Ganonema farinosum y Ulva dactylifera mostraron CMI = 0.1 g mL-1 en contra E. aerogenes. Sólo Colpomenia sinuosa (07-008) mostró CMI = 0.1 g ml-1 frente a S. aureus. Macrocystis pyrifera (09-019) y Cystoseira osmundacea (06-023) tuvieron CMI = 0.1 g mL-1 contra de P. irgensii y P. elyakovii. Vibrio aestuarinus fue el microorganismo más sensible, habiendo sido inhibido por el 80% de los extractos, de los cuales el 56% de ellos mostró una CMI = 0.1 g mL-1. En el caso de las microalgas, se observó un efecto inhibitorio en algunos casos, mientras que en otros casos se observó un afecto activador del crecimiento. Siete (12.9%) extractos mostraron actividad inhibitoria contra Fragilaria crotonensis. Los más activos fueron el extracto del alga 06-014 (no identificada) y el de Colpomenia tuberculata a 0.1 g mL-1. Por otra parte 8 (14. 8%) tuvieron un efecto activador sobre F. crotonensis, los extractos de S. horridum (04-003), Codium amplivesiculatum (04-004), Rosenvingea intricata (04- 020) y Macrocystis pyrifera (06-019) fueron los más activos (0.1 g mL-1). Sobre Cosmarium sp., sólo 3 (5.5%) de los extractos mostraron actividad inhibitoria. Rosenvingea intricata (06-004), Liagora californica (06-008) y Gelidium robustum (06-033) mostraron un efecto inhibidor a 1.0, 0.1 y 0.1 g mL-1, respectivamente. Cinco (9.2%), extractos tuvieron un efecto inductor sobre Cosmarium sp., Porphyra peforata (06-020) fue el extracto más activo (0.1 g mL-1). Scenedesmus armatus fue inhibido por 11 (20.3%) extractos, Rosenvingea intricata (06-004), Corallina vancouvereiencis (06-025) e Hypnea johnstonii (06-035) mostraron actividad a 0.1 g ml-1, 7 (12.9 %) tuvieron un efecto inductor, de los cuales los extractos de Laurencia johnstonii (04-005), Gelidium robustum (04-008), Padina concrescens (06-018) y Macrocystis pyrifera (06-019) fueron activos a 0.1 g mL-1. La segunda parte de la tesis se centra en la obtención de compuestos bioactivos a partir de Padina mexicana y Sargassum horridum. El extracto etanólico de P. mexicana y sus fracciones se evaluaron por su capacidad para reducir el radical libre estable DPPH y su capacidad para inhibir el crecimiento de tres bacterias patógenas [S. aureus (ATCC BAA-42), S. pyogenes (ATCCBAA-946) y E. coli (ATCCBAA-196)] por el método de difusión en agar con discos. Nuestros resultados muestran una interesante actividad secuestrante en la fracción obtenida con EtOAc (ESL1F2) la cual mostró una EC50 = 45.5 g mL-1. En el fraccionamiento de ESL1F2 por cromatografía en columna, se obtuvieron 13 fracciones de las cuales las fracciones polares CCAF10, CCAF11, CCAF12 Y CCAF13 mostraron una EC50 = 12.0, 200.0, 220.0, 130.0 y 23.0 g mL-1 respectivamente. Las fracciones ESL1F1, ESL1F2 y ESL1F3 mostraron actividad inhibitoria contra S. aureus y S. pyogenes, además la fracción ESL1F2 mostró actividad frente a E. coli a una concentración de 2 mg disco-1. En este estudio se aislaron los compuestos conocidos glicerol, manitol y (2S)-1-oleoil-2-3-palmitoil-O- β-D-galactopiranosil-glicerol. El alga, S. horridum fue estudiada como fuente de compuestos con actividad inhibitoria contra M. tuberculosis. El extracto de esta alga mostró una CMI = 6.25 g mL-1 frente a M. tuberculosis. En el fraccionamiento del extracto activo se aislaron fucosterol, ácido mirístico y un compuesto cuya estructura actualmente se encuentra en proceso de elucidación. El ácido mirístico fue el único que mostró actividad contra M. tuberculosis con una CMI = 50 g mL-1. Abstract In this work we studied the ethanolic extracts of 62 species of algae collected along the peninsula of Baja California Sur, Mexico, for its potential as a source of bioactive compounds. The antibacterial, antioxidant, cytotoxic, anti-biofouling and inhibitory mechanisms of bacterial resistance to antibiotics were the activities evaluated in this thesis. The first part of the thesis focuses on identifying the most promising algae as a source of compounds active against antibiotic-resistant pathogenic bacteria [Staphylococcus aureus (ATCC BAA-42), Streptococcus pyogenes (ATCC BAA-946) and Escherichia coli (ATCC BAA-196)] with known resistance mechanisms, likewise, against Mycobacterium tuberculosis, the active extracts against M. tuberculosis were analyzed for their cytotoxic activity against Vero cell line. Also, the first part comprises a study of selection of the active extracts against microorganisms that cause bio-fouling on surfaces submerged in water (three terrestrial, three marine microorganisms, and three freshwater microalgae). The most relevant results on the effect of the extracts as inhibitors of bacterial resistance mechanism of ethanol extracts of 62 tested, 12 (20%) of them in combination with ampicillin were able to reverse the resistance of S. aureus and 8 (13%) with erythromycin of S. pyogenes. Sargassum horridum extract (04-003) was the only one who reversed the resistance of S. aureus and S. pyogenes to ampicillin and erythromycin, respectively. Additionally, 80% of the extracts were active against at least one of the test organisms and 51% against two microorganisms tested. In the trial against M. tuberculosis only 5 (8%) extracts showed activity: Laurencia johnstonii (04-005) with a MIC = 12.5 μg mL-1, 3.13 μg mL-1 for Laurencia sp., S. horridum (04-003), Pterosiphonia bipinnata (07-003) and Laurencia pacifica with a MIC = 6.25 μg mL-1. The MIC of these extracts on cytotoxicity tests were 19.05 μg mL-1 for S. horridum,

  • Potencial farmacológico de algas marinas de Baja California Sur, México
    Instituto Politécnico Nacional (IPN), 2010
    Co-Authors: Muñoz Ochoa Mauricio
    Abstract:

    En este trabajo se estudiaron los extractos etanólicos de 62 especies de algas recolectadas a lo largo de la península de Baja California Sur, México, por su potencial como fuente de compuestos bioactivos. La actividad antibacteriana, antioxidante, citotóxica, anti-bioincrustante e inhibitoria de los mecanismo de resistencia bacteriana a los antibióticos fueron las actividades evaluadas en este trabajo de tesis. La primera parte de la tesis se centra en la identificación de las algas más prometedoras como fuente de compuestos con activos contra bacterias patógenas resistentes a antibióticos [Staphylococcus aureus (ATCC BAA-42), Streptococcus pyogenes (ATCC BAA-946) y Escherichia coli (ATCC BAA-196)] con mecanismos de resistencia conocido, así mismo, contra Mycobacterium tuberculosis, los extractos activos contra el M. tuberculosis se analizaron por su actividad citotóxica contra la línea celular VERO. También, la primera parte comprende un estudio de selección de los extractos activos frente a microorganismos causantes de la bioincrustación en superficies sumergidas en agua (3 microorganismos terrestres, tres marinos y 3 microalgas). Los resultados más relevantes en cuanto al efecto de los extractos como inhibidores de los mecanismo de resistencia bacteriana, de los 62 extractos etanólicos probados, 12 (20%) de ellos en combinación con la ampicilina fueron capaces de revertir la resistencia de S. aureus y 8 (13%) con eritromicina la de S. pyogenes. El extracto de Sargassum horridum (04-003) fue el único que revirtió la resistencia de S. aureus y S. pyogenes a la ampicilina y eritromicina, respectivamente. Adicionalmente el 80% de los extractos fueron activos contra al menos uno de los microorganismos de prueba y el 51% contra dos microorganismos probados. En el ensayo contra M. tuberculosis solo 5 (8%) extractos mostraron actividad: Laurencia johnstonii (04-005) con una CMI = 12.5 mg mL-1, 3.13 mg mL-1 para Laurencia sp., S. horridum (04-003), Pterosiphonia bipinnata (07-003) y Laurencia pacifica con una CMI = 6.25 mg mL-1. Las CMI de estos extractos en las pruebas de citotoxicidad fueron 19.05 mg mL-1 para S. horridum, < 2 mg mL-1 para L. johnstonii y Laurencia sp., 26.77 mg mL-1 para L. pacifica y 30.76 mg mL-1 para P. bipinnata. En los ensayos de actividad anti-bioincrustrante, 54 extractos fueron evaluados por su capacidad para inhibir el crecimiento de un grupo de microorganismos formadores de incrustraciones, entre llos: E. coli (ATCC 23176), Enterobacter aerogenes (ATCC 13048), S. aureus (ATCC 25923), Pseudoalteromonas elyakovii (ATCC 700519), Polaribacter irgensii (ATCC 700398) Vibrio aestuarianus (ATCC 35048), Fragilaria crotonensis, Scenedesmus armatus y Cosmarium sp. La concentración mínima inhibitoria (CMI) de todos los extractos activos se encontró en el rango de 0,1 a 50 mg mL-1. De todos los extractos probados, 4 (7.4%) fueron activos contra E. coli, 9 (16.6%) activos contra E. aerogenes, 3 (5.5%) activos frente a S. aureus, 5 (9.2%) frente a P. ingensii, 7 (12.9%) contra P. elyakovii y 43 (79.6%) frente a V. aestuarianus. Padina mexicana y U. dactylifera fueron las más activas frente a E. coli con una CMI = 1.0 mg mL-1, los extractos de Gelidium robustum, Ganonema farinosum y Ulva dactylifera mostraron CMI = 0.1 mg mL-1 en contra E. aerogenes. Sólo Colpomenia sinuosa (07-008) mostró CMI = 0.1 mg ml-1 frente a S. aureus. Macrocystis pyrifera (09-019) y Cystoseira osmundacea (06-023) tuvieron CMI = 0.1 mg mL-1 contra de P. irgensii y P. elyakovii. Vibrio aestuarinus fue el microorganismo más sensible, habiendo sido inhibido por el 80% de los extractos, de los cuales el 56% de ellos mostró una CMI = 0.1 mg mL-1. En el caso de las microalgas, se observó un efecto inhibitorio en algunos casos, mientras que en otros casos se observó un afecto activador del crecimiento. Siete (12.9%) extractos mostraron actividad inhibitoria contra Fragilaria crotonensis. Los más activos fueron el extracto del alga 06-014 (no identificada) y el de Colpomenia tuberculata a 0.1 mg mL-1. Por otra parte 8 (14. 8%) tuvieron un efecto activador sobre F. crotonensis, los extractos de S. horridum (04-003), Codium amplivesiculatum (04-004), Rosenvingea intricata (04-020) y Macrocystis pyrifera (06-019) fueron los más activos (0.1 mg mL-1). Sobre Cosmarium sp., sólo 3 (5.5%) de los extractos mostraron actividad inhibitoria. Rosenvingea intricata (06-004), Liagora californica (06-008) y Gelidium robustum (06-033) mostraron un efecto inhibidor a 1.0, 0.1 y 0.1 mg mL-1, respectivamente. Cinco (9.2%), extractos tuvieron un efecto inductor sobre Cosmarium sp., Porphyra peforata (06-020) fue el extracto más activo (0.1 mg mL-1). Scenedesmus armatus fue inhibido por 11 (20.3%) extractos, Rosenvingea intricata (06-004), Corallina vancouvereiencis (06-025) e Hypnea johnstonii (06-035) mostraron actividad a 0.1 mg ml-1, 7 (12.9 %) tuvieron un efecto inductor, de los cuales los extractos de Laurencia johnstonii (04-005), Gelidium robustum (04-008), Padina concrescens (06-018) y Macrocystis pyrifera (06-019) fueron activos a 0.1 mg mL-1. La segunda parte de la tesis se centra en la obtención de compuestos bioactivos a partir de Padina mexicana y Sargassum horridum. El extracto etanólico de P. mexicana y sus fracciones se evaluaron por su capacidad para reducir el radical libre estable DPPH y su capacidad para inhibir el crecimiento de tres bacterias patógenas [S. aureus (ATCC BAA-42), S. pyogenes (ATCCBAA-946) y E. coli (ATCCBAA-196)] por el método de difusión en agar con discos. Nuestros resultados muestran una interesante actividad secuestrante en la fracción obtenida con EtOAc (ESL1F2) la cual mostró una EC50 = 45.5 mg mL-1. En el fraccionamiento de ESL1F2 por cromatografía en columna, se obtuvieron 13 fracciones de las cuales las fracciones polares CCAF10, CCAF11, CCAF12 Y CCAF13 mostraron una EC50 = 12.0, 200.0, 220.0, 130.0 y 23.0 mg mL-1 respectivamente. Las fracciones ESL1F1, ESL1F2 y ESL1F3 mostraron actividad inhibitoria contra S. aureus y S. pyogenes, además la fracción ESL1F2 mostró actividad frente a E. coli a una concentración de 2 mg disco-1. En este estudio se aislaron los compuestos conocidos glicerol, manitol y (2S)-1-oleoil-2-3-palmitoil-O-β-D-galactopiranosil-glicerol. El alga, S. horridum fue estudiada como fuente de compuestos con actividad inhibitoria contra M. tuberculosis. El extracto de esta alga mostró una CMI = 6.25 mg mL-1 frente a M. tuberculosis. En el fraccionamiento del extracto activo se aislaron fucosterol, ácido mirístico y un compuesto cuya estructura actualmente se encuentra en proceso de elucidación. El ácido mirístico fue el único que mostró actividad contra M. tuberculosis con una CMI = 50 mg mL-1