Nonradiative relaxation of high-energy excited states to the lowest excited state in chlorophylls marks the first step in the process of photosynthesis. We perform ultrafast transient absorption spectroscopy measurements, that reveal this internal conversion dynamics to be slightly slower in chlorophyll B than in chlorophyll A. Modeling this process with non-adiabatic excited state molecular dy...

in order to evaluate the effects of foliar application of methanol on some physiological characteristics of chickpea under drought stress, an experiment was conducted as a factorial based on completely randomized design with three replications in 2011 at the recearch center of plant for sciences in ferdowsi university of mashhad. the first factor was different levels of methanol including, 0 (c...

nickel and cadmium are heavy metals with some hazards for plant metabolism. the impacts of nickel chloride (0, 400 and 800 μm) in the presence of vitamin b complex (0, 30 and 60 ml from pharmacy commercial stock) and the impacts of cadmium chloride (0, 100, 200, 300, 400, 500 and 600 μl from 100 µm stock) in pot and cadmium nitrate (0, 100, 200, 400, 800, 1600 and 3200 μl from 100 µm stock) in ...

A primary symptom of diuron (DCMU) phytotoxicity in plants is the destruction of chlorophyll. To study this process in vitro, chloroplasts from pea leaves (Pisum sativum L.) have been incubated in the light with DCMU for periods of up to 34 hours. The sequence of photodestruction of chlorophylls and carotenoids has been followed to try and establish the nature of the chloroplast protection mech...

Solvent extracts of three different prokaryotic algae from three species of didemnid ascidians contained pigments identified, on the basis of their fluorescence excitation (E)and fluorescence emission (F)spectral maxima (measured in nm) at 77K, as chlorophyll a (E 449, F 678) and chlorophyll b (E 478, F 658). The release of algae on cutting or freezing Diplosoma virens was accompanied by a stro...

Effects of two blanching conditions using peroxidase (POD) and lipoxygenase (LOX) as indicator enzyme on residual enzyme activities, ascorbic acid and chlorophyll content in green beans during frozen storage were studied. No reactivation of both LOX and POD enzyme was observed during storage. The losses of ascorbic acid and chlorophylls during storage followed first order kinetics. Half-life of...

A collection of 17 monoclonal antibodies elicited against the light-harvesting chlorophyll a/b protein complex which serves photosystem II (LHC-II) of Pisum sativum shows six classes of binding specificity. Antibodies of two of the classes recognize a single polypeptide (the 28- or the 26- kD polypeptides), thereby suggesting that the two proteins are not derived from a common precursor. Other ...

Light induced redox reactions in photosystem I in photosynthesis of green plants are indicated by absorp tion changes with maxima at 430 nm and 705 nm. These negative going absorption changes have been attributed to the rapid photooxidation of a special chlorophyll namedP 700 [l] or chlorophyll-u1 [2] . The extremely rapid oxidation of this pigment [3] contributes to the extremely rapid generat...