For over two decades H. VON EULER (3) and his coworkers have studied the relationship of catalase to chlorophyll. In their work they utilized various chlorophyll defective plants including genetic albinos, variegated, chlorotic and etiolated plants. In general, they found a parallelism between chlorophyll content and catalase activity. NAKAMURA (11) working with a number of higher and lower for...

5-aminolevulinic acid (ALA) is a precursor in the biosynthesis of tetrapyrroles including chlorophylls and heme. The formation of ALA involves two enzymatic steps which take place in the chloroplast in plants. The first enzyme, glutamyl-tRNA reductase, and the second enzyme, glutamate-1-semialdehyde-2,1-aminomutase, are encoded by the nuclear HEMA and GSA genes, respectively. To assess the sign...

The growth of photoautotrophic Euglena gracilis Z is strongly inhibited by manganese deficiency, whereas chlorophyll formation is not appreciably affected. The galactosyldiglyceride content of the manganese-deficient photo-autotrophic Euglena was about 40% lower on the basis of either chlorophyll content or dry weight. When dark-grown cultures of Euglena were grown photoheterotrophically in lig...

A three-dimensional water quality model was developed for simulating temporal and spatial variations of phytoplankton, nutrients, and dissolved oxygen in freshwater bodies. Effects of suspended and bed sediment on the water quality processes were simulated. A formula was generated from field measurements to calculate the light attenuation coefficient by considering the effects of suspended sedi...

increasing energy demands associated with economic growth and industrialization have resulted in dramatic increases in air pollution emissions. air pollution damages the plant mainly by disrupting cell homeostatic conditions.in the present study, diverse plant criteria indicating air pollution from different levels including cell biochemistry, leaf and tree crown in the plane-tree were determin...

The net photosynthetic rate, chlorophyll content, chlorophyll fluorescence and 820 nm transmission were investigated to explore the behavior of the photosynthetic apparatus, including light absorption, energy transformation and the photoactivities of photosystem II (PSII) and photosystem I (PSI) during senescence in the stay-green inbred line of maize (Zea mays) Q319 and the quick-leaf-senescen...

Color changes often accompany the onset of ripening, leading to brightly colored fruits that serve as attractants to seed-dispersing organisms. In many fruits, including tomato (Solanum lycopersicum) and pepper (Capsicum annuum), there is a sharp decrease in chlorophyll content and a concomitant increase in the synthesis of carotenoids as a result of the conversion of chloroplasts into chromopl...

The city of Ushuaia, Argentina, has experienced a rapid and unorganized population growth with possible consequences on the dynamics functioning urban lotic ecosystems. Urban expansion was not largely accompanied by development infrastructure for provision services such as drinking water sewers to all population. Currently, only 65% is connected main sewage system (pre-treatment) does have seco...

The reflectance properties of leaves are influenced by diverse biochemical components including chlorophyll, one of the key indicators related to plant photosynthesis and plant stress. Although a number of hyperspectral indices have been proposed for quantifying leaf chlorophyll concentrations, their applications are largely restricted to where they were developed and can hardly provide satisfa...

An assay technique, homogeneous enzyme immunoassay, is described for the quantitative determination of morphine derivatives in biological fluids. An enzyme is labeled with morphine. When the enzymelabeled morphine is bound by antimorphine antibodies, the enzyme is rendered inactive. Free morphine competes with enzyme-morphine for antibody binding sites preventing inhibition of enzyme activity. ...