Biomaterial Database

Spectrofluorometric estimation of intermediates of chlorophyll biosynthesis: protoporphyrin IX, Mg-protoporphyrin, and protochlorophyllide. 1992

P Hukmani, and B C Tripathy

School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.

A highly sensitive spectrofluorometric method for quantitative estimation of certain precursors of chlorophyll biosynthesis from the mixtures of plant tetrapyrroles having overlapping fluorescence emission spectra is developed. At room temperature (293 degrees K) protoporphyrin IX is monitored from its emission maximum, 633 nm, when excited at 400 nm (E400/F633). Protochlorophyllide is estimated at 638 nm, while being excited at 440 nm (E440/F638). Mg-protoporphyrin+Mg-protoporphyrin monoester pool has emission around 589-592 nm. Therefore the integration value of the emission band that extends from 580 to 610 nm is taken to calibrate its concentration. This spectrofluorometric method designed for the determination of protoporphyrin IX, esterified and nonesterified Mg-protoporphyrin pool, and protochlorophyllide is far superior to available spectrophotometric methods and estimates as low as 1 nM concentration of plant pigments. As minute quantities of individual pigments can be quantitatively analyzed from their mixtures, this method eliminates analytical uncertainties due to recovery losses caused by chromatography. However, only dilute samples can be estimated by this spectrofluorometric method as the quantitative relation between fluorescence and concentration deviates from linearity at high, i.e., above 150 nM, concentrations of pigment to be quantified.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008432	Mathematical Computing	Computer-assisted interpretation and analysis of various mathematical functions related to a particular problem.	Statistical Computing,Computing, Statistical,Mathematic Computing,Statistical Programs, Computer Based,Computing, Mathematic,Computing, Mathematical,Computings, Mathematic,Computings, Mathematical,Computings, Statistical,Mathematic Computings,Mathematical Computings,Statistical Computings
D011521	Protochlorophyllide	A photo-active pigment localized in prolamellar bodies occurring within the proplastids of dark-grown bean leaves. In the process of photoconversion, the highly fluorescent protochlorophyllide is converted to chlorophyll.	Protochlorophyllide A,MV-PChlide,Monovinyl Protochlorophyllide,MV PChlide,Protochlorophyllide, Monovinyl
D011524	Protoporphyrins	Porphyrins with four methyl, two vinyl, and two propionic acid side chains attached to the pyrrole rings. Protoporphyrin IX occurs in hemoglobin, myoglobin, and most of the cytochromes.
D002623	Chemistry Techniques, Analytical	Methodologies used for the isolation, identification, detection, and quantitation of chemical substances.	Analytical Chemistry Techniques,Analytical Chemistry Methods,Analytical Chemistry Method,Analytical Chemistry Technique,Chemistry Method, Analytical,Chemistry Methods, Analytical,Chemistry Technique, Analytical,Method, Analytical Chemistry,Methods, Analytical Chemistry,Technique, Analytical Chemistry,Techniques, Analytical Chemistry
D002734	Chlorophyll	Porphyrin derivatives containing magnesium that act to convert light energy in photosynthetic organisms.	Phyllobilins,Chlorophyll 740
D002735	Chlorophyllides	Products of the hydrolysis of chlorophylls in which the phytic acid side chain has been removed and the carboxylic acids saponified.	Chlorophyllide
D005453	Fluorescence	The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.
D006586	Hexanes	Six-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives. Various polyneuropathies are caused by hexane poisoning.	Hexane,Isohexane,Isohexanes
D000096	Acetone	A colorless liquid used as a solvent and an antiseptic. It is one of the ketone bodies produced during ketoacidosis.