Wildfire impacts on phytoplankton communities of three small lakes on the Boreal Plain, Alberta, Canada: a paleolimnological study

2003 ◽  
Vol 60 (5) ◽  
pp. 584-593 ◽  
Author(s):  
T Charette ◽  
E E Prepas
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Phytoplankton Community ◽  
Sedimentary Pigments ◽  
Small Lakes ◽  
Headwater Lakes ◽  
Phytoplankton Communities ◽  
Β Carotene ◽  
Cyanobacterial Biomass

Quantification of sedimentary pigments with high performance liquid chromatography enabled the examination of changes in phytoplankton community indicators after wildfire in three lakes on the Boreal Plain with 50-year sediment chronologies. The response of phytoplankton indicators to wildfire was strongest in the shallow Lake B19, with post-fire increased concentrations of β-carotene (all phytoplankton), cyanobacterial pigments (echinenone, canthaxanthin), and lutein (chlorophytes) (p < 0.05). In the relatively deep headwater Lake B3, the indicator for all phytoplankton was not different after fire (p = 0.3), but important changes occurred in the phytoplankton community for 4 years after fire. The concentrations of cyanobacterial (echinenone, myxoxanthophyll) and diatoms + chrysophytes (fucoxanthin) indicators were higher and lower (p < 0.05), respectively, after fire. The relatively deep and non-headwater Lake B4 was little impacted by fire. An increase in cyanobacterial biomass after fire is most likely to occur in shallow headwater lakes on the Boreal Plain.

Phytoplankton community during a coccolithophorid bloom in the Patagonian Shelf: microscopic and high-performance liquid chromatography pigment analyses

2011 ◽  
Vol 92 (1) ◽  
pp. 13-27 ◽  
Author(s):  
Márcio Silva de Souza ◽  
Carlos Rafael Borges Mendes ◽  
Virgínia Maria Tavano Garcia ◽  
Ricardo Pollery ◽  
Vanda Brotas
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Phytoplankton Community ◽  
Sampling Period ◽  
Emiliania Huxleyi ◽  
Patagonian Shelf ◽  
Phaeocystis Antarctica ◽  
Hplc Data ◽  
Phytoplankton Group

We describe the phytoplankton community and biomass during a summer coccolithophorid bloom sampled over the Patagonian shelf (48.5°S–50.5°S). Those phytoplankton species can contribute to the flux of calcium carbonate out of surface waters. Results from both microscope and high-performance liquid chromatography (HPLC) analysis are shown to complement information on the phytoplankton community. From CHEMTAX analysis of HPLC data, the most important organisms and groups identified were the coccolithophorid Emiliania huxleyi, the haptophyte Phaeocystis antarctica, dinoflagellates, diatoms, cryptophytes, prasinophytes and cyanobacteria. Phytoplankton microscope counts were converted into phytoplankton group-specific biovolume estimates. Although some microscope-identified taxa could not be determined by CHEMTAX, e.g. the autotrophic ciliate Myrionecta rubra, cluster analyses from both techniques showed similar results for the main groups. Both Emiliania huxleyi cell concentration and biomass, and the pigment 19′-hexanoyloxyfucoxanthin were the most important biological features during the sampling period. At surface, nitrate was moderately high (0.2–4.2 µM) in coccolithophorid-dominated samples, whereas phosphate (<0.33 µM) and silicate (<1.35 µM) concentrations were low. Among the environmental factors low Si:N ratios were mainly associated with the dominance of E. huxleyi. Competition and probably differential grazing could also promote a coccolithophorid outgrowth over other photoautotrophs during the summer season in the Patagonian shelf.

scholarly journals Simultaneous determination of retinol, retinyl palmitate and β-carotene in rat serum treated with 7,12-dimethylbenz[a]anthracene and Hypericum Perforatum L. by high-performance liquid chromatography with diode-array detection

2010 ◽  
Vol 8 (1) ◽  
pp. 108-115 ◽  
Author(s):  
Abdulkadir Levent ◽  
Suat Ekin ◽  
Gökhan Oto
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Hypericum Perforatum ◽  
Treated Group ◽  
Retinyl Palmitate ◽  
Rat Serum ◽  
Array Detection ◽  
Hypericum Perforatum L ◽  
Β Carotene

AbstractA new and simple high-performance liquid chromatography method was developed and validated for the simultaneous determination of retinol, retinyl palmitate and β-carotene in rat serum treated with Hypericum Perforatum L. and 7,12-dimethylbenz[a]anthracene. Furthermore, vitamin C was determined spectrophotometrically. High-performance liquid chromatography analysis was performed utilizing an Inertsil ODS3 reversed phase column with methanol-acetonitrile-tetrahydrofuran (65:30:5, v/v/v) as mobile phase, at a flow rate of 1.5 mL min−1 and 40°C. Diode-array detection was conducted at 325 and 450 nm for retinol and retinyl palmitate, and β-carotene, respectively with a running time of 26 min. The high-performance liquid chromatography assay and extraction procedure proposed are simple, rapid, sensitive and accurate. This method was then applied to determine the amounts of retinol, retinyl palmitate and β-carotene in rat serum. Results of this study demonstrated that at 60th day in the 7,12-dimethylbenz[a]anthracene-treated group there was a significant decrease (pa] anthracene + Hypericum Perforatum L. treated group compared to the control group..

Quantification of Provitamin A Compounds in ChInese Vegetables by High-Performance Liquid Chromatography

1993 ◽  
Vol 56 (1) ◽  
pp. 51-54 ◽  
Author(s):  
B. H. CHEN ◽  
J. R. CHUANG ◽  
J. H. LIN ◽  
C. P. CHIU
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Provitamin A ◽  
Photodiode Array Detection ◽  
Carotene Content ◽  
Green Pepper ◽  
Photodiode Array ◽  
Mustard Green ◽  
Β Carotene

The provitamin A contents of 16 vegetables grown in Taiwan were analyzed by high-performance liquid chromatography with photodiode-array detection. The amounts of the major provitamin A compounds, (β-cryptoxanthin, α-carotene, and β-carotene ranged from 0–6.8, 0–27.7, and 0.6–104.9 (μg/g, respectively. The highest β-carotene content was found in basil, followed by onion fragrant, kale, carrot, spinach, water convolvulus, mustard, green onion, garland chrysanthemum, sweet potato, green pepper, yellow com, mustard stem, lettuce, cabbage, and celeriac. Carrot was the only vegetable found to contain α-carotene while com was the vegetable to contain (β-cryptoxanthin.

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