The chlorophylls are the main pigments in green plants, algae and other photosynthetic microorganisms. They belong to a class of pyrrole ring compounds known as porphins. Derivatives of porphins are called porphyrins. Phorbin, a porphyrin formed by the addition of another ring structure, serves as the basis for all chlorophyll molecules (Fig. 2.1). Different types of chlorophyll may arise depen...

Phytochrome A (phyA) mRNA abundance decreased rapidly in total RNA samples isolated from 4-day-old etiolated oat seedlings following a red light pulse. Putative in vivo phyA mRNA degradation products were detectable both before and after red light treatment. Cordycepin-treated coleoptiles were unable to accumulate the chlorophyll a/b-binding protein mRNA in response to red light, indicating tha...

Degradation of chlorophyll in spinach (Spinacia olearacea L. cv. Hybrid 612) appeared to be regulated through the peroxidase-hydrogen peroxide pathway, which opens the porphyrin ring, thus resulting in a colorless compound. This conclusion was arrived at from the analysis of chlorophylls (Chls) and their metabolizes by HPLC and of enzyme activities catalyzing the degradative reactions. Chls dec...

Plants are able to recognize even small changes in surrounding temperatures to optimize their growth and development. At warm temperatures, plants exhibit diverse architectural adjustments, including hypocotyl and petiole elongation, leaf hyponasty, and reduced stomatal density. However, it was previously unknown how such warm temperatures affected the early stages of seedling development. In o...

In cold extracts of senescent leaves of the Lime tree (Tilia cordata), two colorless nonfluorescent chlorophyll catabolites (NCCs) were identified, named Tc-NCC-1 and Tc-NCC-2, as well as a polar yellow chlorophyll catabolite (YCC), named Tc-YCC. The constitution of the two NCCs was determined by spectroscopic means. In addition, a tentative structure was derived for Tc-YCC. The three chlorophy...

In this work a study of critical storage temperatures on pigment degradation of green beans (Phaseolus vulgaris, cvs. Perona and Boby) was conducted. In this way, green beans kept better quality at 4 degrees C than either 8 or 12 degrees C, maintaining a bright green color and good texture. Nevertheless, temperatures of 4 degrees C induced chilling injury (CI) after eight days of storage, which...

The aim of the present study was to find methods for enhancing rates of hydrocarbon biodegradation in gasoline contaminated soil by ex situ bioremediation. Red soil (RS) was treated with gasoline-spilled soil (GS) from a gasoline station and different combinations of amendments were prepared using (i) mixed bacterial consortium (MC), (ii) poultry litter (PL), (iii) coir pith (CP) and (iv) rhamn...

Euglena, Chlorophyll Degradation, Pyropheophytin, Photosynthesis, High Performance Chromatography Light-grown non-dividing cells of Euglena gracilis Klebs var. bacillaris Cori form pheophytin a like pigments from chlorophyll a without loss of viability when they are allowed to incubate in darkness without shaking. This is accompanied by the loss of long-wavelength components in the red absorpti...

Serious environmental degradation of aquatic ecosystems has been caused by eutrophication and by pollutants such as herbicides. Therefore, measurement of in situ algal photosynthetic activity is important for environmental monitoring. With ordinary nonimaging fluorometers, algal chlorophyll fluorescence can be measured easily, but heterogeneity within samples cannot be detected. Effects of a he...

Members of the AtPep group of Arabidopsis endogenous peptides have frequently been reported to induce pattern-triggered immunity (PTI) and to increase resistance to diverse pathogens by amplifying the innate immune response. Here, we made the surprising observation that dark-induced leaf senescence was accelerated by the presence of Peps. Adult leaves as well as leaf discs of Col-0 wild type pl...