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Canthaxanthin in recent sediments as an indicator of heterocystous cyanobacteria in coastal waters

Krajewska Magdalena, Szymczak-Żyła Małgorzata, Kobos Justyna, Witak Małgorzata, Kowalewska Grażyna

Oceanologia

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2019

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No. 61 (1)

78--88

EN

The mean share of heterocystous cyanobacteria in total chlorophyll-a production in coastal waters, based on cyanobacterial marker carotenoid and chloropigments preserved in recent sediments (0-5 cm, ca 30 years), has been studied in the Gulf of Gdańsk (southern Baltic) and for comparison in the Oslofjord/Drammensfjord (southern Norway). First of all, Baltic cyanobacteria, both from laboratory cultures and field samples, were analysed to select marker heterocysteous cyanobacteria carotenoids for sediments. The pigment relation to diatom percentages of different salinity preferences has been tested, to confirm origin of cyanobacteria. The results indicate that canthaxanthin is the best marker of heterocystous cyanobacteria in the southern Baltic Sea. These filamentous cyanobacteria inflow to the Gulf of Gdańsk from the open sea and their abundance has increased in the last thirty years, in comparison with previous time. In that period they made up ca 4.6% of the total chlorophyll-a production in the Gulf of Gdańsk. The estimate for Oslofjord, at the same assumptions, suggests that heterocystous cyanobacteria occurred there also (up to 5.8% of the total chlorophyll-a production), were of marine origin, but their abundance has decreased during the last thirty years. Such an estimate may be used in environmental modelling and can be applied to other coastal areas, once the marker pigments of the main cyanobacteria species have been identified, and the percentage of total chlorophyll-a produced in a basin, preserved in sediments, has been determined for such area.

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A simplified and small-scale sample preparation technique for determining astaxanthin, canthaxanthin, and β-apo-8′-carotenoic acid ethyl ester in hen’s egg yolk

Furusawa N.

Acta Chromatographica

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2014

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Vol. 26, no. 4

587--597

EN

This paper described a fast, simple, and small scale method of sample preparation followed by high-performance liquid chromatography (HPLC) coupled photodiode array (PDA) detector for simultaneous quantification of astaxanthin, canthaxanthin, and β-apo-8′-carotenoic acid ethyl ester in hen’s egg yolk. The HPLC-PDA was performed on a C18 column with an isocratic mobile phase. Analytes were extracted from the sample using a handheld ultrasonic homogenizer, and purified by MonoSpin®-SI, a centrifugal monolithic silica spin mini-columns, and quantified within 30 min. The proposed method obtained average recoveries for the three analytes in the range of 70.5–101.1% with relative standard deviations ≤5.0%. The quantitation limits were 0.3 μg g -1 for AX, 0.5 μg/g for CX, and 1.0 μg g−1 for ACAEE, respectively.

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Astaxanthin, canthaxanthin and astaxanthin esters in the copepod Acartia bifilosa (Copepoda, Calanoida) during ontogenetic development [commun.]

Lotocka M., Styczyńska-Jurewicz E.

Oceanologia

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2001

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No. 43 (4)

487-497

EN

The contents of astaxanthin, canthaxanthin and astaxanthin esters were studied in natural populations of the copepod Acartia bifilosa from the Pomeranian Bay and Gulf of Gdansk in the southern Baltic Sea. Samples dominated by any one of three developmental groups: (1) nauplii, (2) copepodids I-III and (3) copepodids IV-V and adults of Acartia bifilosa were analysed by means of high performance liquid chromatography (HPLC). As ontogenetic development progressed, significant changes occurred in the proportion of particular pigments in the total pigment pool of the various developmental groups. Astaxanthin and canthaxanthin occurred in all the groups, the former being clearly dominant. However, an increasing percentage of astaxanthin esters was recorded in the copepodids I-III, and even more in the copepodids IV-V and adults group. Most probably, astaxanthin is the main pigment active in copepod lipid metabolism. Carotenoid pigments in copepods very likely act as efficient free-electron quenchers and may be involved as antioxidants in rapid lipid metabolism. The exogenously feeding stages (late nauplii and copepodids) transform plant carotenoids taken from food and are evidently capable of metabolising astaxanthin by esterification and further degradation. It is emphasised that, according to literature data, astaxanthin esters may have an even higher quenching ability. It is suggested that crustacean carotenoid pigments, with their electron donor-acceptor abilities, may replace oxygen in peroxidation processes connected with lipid metabolism. The consequences of such a physiological role of astaxanthin for present-day estimations of energy balances in zooplankton communities are mentioned.