The chemical structural differences distinguishing chlorophylls in oxygenic photosynthetic organisms are either formyl substitution (chlorophyll b, d, and f) or the degree of unsaturation (8-vinyl chlorophyll a and b) of a side chain of the macrocycle compared with chlorophyll a. We conducted an investigation of the conversion of vinyl to formyl groups among naturally occurring chlorophylls. We...

in this research, catalase activity and leaf chlorophyll stability of satsuma mandarin on some citrus rootstocks under waterlogging condition were studied. experiment was conducted as factorial with randomized complete blocks and 6 replications. the first factor, include 7 soils from east mazandaran and the second factor included 7 different citrus rootstocks: 1. sour orange, 2. swingle citrome...

The MERIS Terrestrial Chlorophyll Index (MTCI), a standard level 2 ESA product, provides information on the chlorophyll content of vegetation (amount of chlorophyll per unit area of ground). This is a combination of information on leaf area index (LAI, area of leaves per unit area of ground) and the chlorophyll concentration of those leaves. The MTCI correlates strongly with chlorophyll content...

The blue-green alga, Anacystis nidulans, was grown in lights of different colors and intensities, and its absorption and fluorescence properties were studied. Strong orange light, absorbed mainly by phycocyanin, causes reduction in the ratio of phycocyanin to chlorophyll a; strong red light, absorbed mainly by chlorophyll, causes an increase in this ratio. This confirms the earlier findings of ...

During leaf senescence, chlorophyll is removed from thylakoid membranes and converted in a multistep pathway to colorless breakdown products that are stored in vacuoles. Dephytylation, an early step of this pathway, increases water solubility of the breakdown products. It is widely accepted that chlorophyll is converted into pheophorbide via chlorophyllide. However, chlorophyllase, which conver...

This work represents an application of the Visible Spectrometry, High Pressure Liquid Cromatography and Electronspray Ionisation-Mass Spectrometry analysis for the identification of chlorophyll and its derivatives, pheophytin and chlorophyllide, in their purified mixtures (the chlorophyll, pheophytin and chlorophyllide fraction, respectively). The chlorophyll, pheophytin and chlorophyllide frac...

Accurate quantification of pigments in mixtures is essential in all cases in which separation of pigments by chromatography is impracticable for one reason or another. An example is the analysis of in vivo formation of heavy metal-substituted chlorophylls in heavy metal-stressed plants. We describe here a novel, accurate UV/VIS spectrophotometric method for the quantification of individual chlo...