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Specimens of the red alga Bostrychia tenella J. Agardh (Rhodomelaceae, Ceramiales) were collected from the São Paulo coast and submitted to room temperature solvent extraction. The resulting extract was fractionated by partitioning with... more
Specimens of the red alga Bostrychia tenella J. Agardh (Rhodomelaceae, Ceramiales) were collected from the São Paulo coast and submitted to room temperature solvent extraction. The resulting extract was fractionated by partitioning with organic solvent. The n-hexane (BT-H) and dichloromethane (BT-D) fractions showed antiprotozoal potential in biological tests with Trypanosoma cruzi and Leishmania amazonensis and presented high activity in an antifungal assay with the phytopathogenic fungi Cladosporium cladosporioides and Cladosporium sphaerospermum. Chromatography methods were used to generate subfractions from BT-H (H01 to H11) and from BT-D (D01 to D19). The subfractions were analyzed by gas chromatography-mass spectrometry (GC/MS), and the substances were identified by retention index (Kovats) and by comparison to databases of commercial mass spectra. The volatile compounds found in marine algae were identified as fatty acids, low molecular mass hydrocarbons, esters and steroids; some of these have been previously described in the literature based on other biological activities. Moreover, uncommon substances, such as neophytadiene were also identified. In a trypanocidal assay, fractions BT-H and BT-D showed IC(50) values of 16.8 and 19.1 microg/mL, respectively, and were more active than the gentian violet standard (31 microg/mL); subfractions H02, H03, D01 and D02 were active against L. amasonensis, exhibiting IC(50) values of 1.5, 2.7, 4.4, and 4.3 microg/mL, respectively (standard amphotericin B: IC(50)=13 microg/mL). All fractions showed antifungal potential. This work reports the biological activity and identification of compounds by GC/MS for the marine red alga B. tenella for the first time.
Research Interests: Analytical Chemistry, Leishmania, Solvent Extraction, Pharmaceutical, Animals, and 13 moreRed Algae, Marine Algae, Plant extracts, Rhodophyta, Trypanosoma Cruzi, Room Temperature, Fatty Acid, Gas Chromatography/mass Spectrometry, Antifungal Agents, Trypanocidal Agents, Biological activity, Volatile Compounds, and Retention Index
... Abstract Tissue culture techniques were applied for micro-propagation of the red alga Kappaphycus alvarezii in order to select the best strain and experimental system for in vitro ... The application of micropropagation in... more
... Abstract Tissue culture techniques were applied for micro-propagation of the red alga Kappaphycus alvarezii in order to select the best strain and experimental system for in vitro ... The application of micropropagation in commercially important seaweeds may help ...
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... At Sitio Grande, three areas along the river were chosen: SGI, upstream; SG2, intermediate; SG3, next to the river mouth. These mangroves are composed basically of Rhizophora mangle L., with some Laguncularia racemosa (L.) Gaert. and... more
... At Sitio Grande, three areas along the river were chosen: SGI, upstream; SG2, intermediate; SG3, next to the river mouth. These mangroves are composed basically of Rhizophora mangle L., with some Laguncularia racemosa (L.) Gaert. and a few Avicen-nia schaueriana Stap. ...
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The selection of seaweed species for their use as biofilters should be based on the knowledge of their nutrient requirements and tolerance to wide variations of nutrient concentrations. Therefore, tolerance and the physiological... more
The selection of seaweed species for their use as
biofilters should be based on the knowledge of their nutrient
requirements and tolerance to wide variations of nutrient concentrations.
Therefore, tolerance and the physiological capabilities
of Hypnea cervicornis J. Agardh (Gigartinales, Rhodophyta) to growth under nitrate, ammonium, and phosphate variations and to assimilate them into soluble proteins and photosynthetic pigments were evaluated in laboratory conditions. Treatments were composed of sterilized seawater
enriched with 25% von Stosch solution (without nitrogen and
phosphorus), and nitrate or ammonium and phosphate were
added in combination of 100:1 and 10:1 nitrogen/phosphorus
(N/P). Nitrate concentrations varied from 0 to 500 μM, and
ammonium concentrations varied from 0 to 50 μM. Growth
rates of H. cervicornis increased linearly with addition of
ammonium, but with nitrate addition, growth varied following
a saturation kinetic, and the highest growth rate (14.45 % d−1)
was observed in 200 μM of N/P ratio of 10:1. An excess of
nutrients was accumulated as proteins and phycobiliproteins
(mainly as allophycocyanin and phycoerythrin) at higher
phosphate availability (N/P ratio of 10:1), and H. cervicornis
tolerated the highest ammonium and nitrate concentrations
(50 and 500 μM, respectively). These physiological responses
suggest that this species could be used as biofilter for nutrient
removal in eutrophicated seawater and could be cultivated in
integrated multitrophic aquaculture systems.
Keywords Ammonium . Hypnea . Nitrate. Nitrogen storage . Pigments . Phosphate . Proteins
biofilters should be based on the knowledge of their nutrient
requirements and tolerance to wide variations of nutrient concentrations.
Therefore, tolerance and the physiological capabilities
of Hypnea cervicornis J. Agardh (Gigartinales, Rhodophyta) to growth under nitrate, ammonium, and phosphate variations and to assimilate them into soluble proteins and photosynthetic pigments were evaluated in laboratory conditions. Treatments were composed of sterilized seawater
enriched with 25% von Stosch solution (without nitrogen and
phosphorus), and nitrate or ammonium and phosphate were
added in combination of 100:1 and 10:1 nitrogen/phosphorus
(N/P). Nitrate concentrations varied from 0 to 500 μM, and
ammonium concentrations varied from 0 to 50 μM. Growth
rates of H. cervicornis increased linearly with addition of
ammonium, but with nitrate addition, growth varied following
a saturation kinetic, and the highest growth rate (14.45 % d−1)
was observed in 200 μM of N/P ratio of 10:1. An excess of
nutrients was accumulated as proteins and phycobiliproteins
(mainly as allophycocyanin and phycoerythrin) at higher
phosphate availability (N/P ratio of 10:1), and H. cervicornis
tolerated the highest ammonium and nitrate concentrations
(50 and 500 μM, respectively). These physiological responses
suggest that this species could be used as biofilter for nutrient
removal in eutrophicated seawater and could be cultivated in
integrated multitrophic aquaculture systems.
Keywords Ammonium . Hypnea . Nitrate. Nitrogen storage . Pigments . Phosphate . Proteins