Article

Spectrophotometric Characteristics of Chlorophylls a and b and Their Phaeophytins in Ethanol

Department of Botany, University of Nijmegen, Nijmegen The Netherlands
Biochimica et Biophysica Acta (BBA) - Biophysics including Photosynthesis 11/1965; 109(2):448-453. DOI: 10.1016/0926-6585(65)90170-6

ABSTRACT

The absorption spectra of chlorophylls a and b in 96% ethanol, and of pheophytins a and b in 80% ethanol-0.01 N hydrochloric acid have been determined in comparison with known absorption coefficients.

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    • "Due to instrument availability, benthic chl a analysis was conducted using both spectrophotometric and fluorometric techniques. From each site, one of the three replicates was analysed on a spectrophotometer following a 24-hour cold ethanol (EtOH) extraction (Wintermans and De Mots 1965) using methods outlined by Bergmann and Peters (1980) and Webb et al. (1992). The remaining two replicates were analysed using a Turner 10AU fluorometer following a 7 minute digestion in 90% EtOH at 808C. "
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    • "Chlorophylls a and b were determined on red and green cheek according to ( Wintermans and Mat , 1965 ) as follows : half gram of fresh peel was extracted by about 15 ml of 85% acetone and 0 . 5 g calcium carbonate , the mixture was filtered through a piece of cotton by using a glass funnel and the residue was washed with a small volume of acetone and brought up to 25 ml . "
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    • "Prior to GC-FAME, approximate lipid concentrations and injection volumes were estimated from chlorophyll contents. Chlorophyll content was quantified in ethanol extracts using the optical density at 654 nm and a specific absorbance coefficient of 39.8 L cm -1 g -1 (Wintermans and de Mots 1965). The chlorophyll/lipid mass ratio was taken as one (Janero and Barrnett 1981; Droppa et al. 1990; Kirchhoff et al. 2002; Kóta et al. 2002). "
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