FTIR spectroscopy is advantageous for detecting changes in polar chemical bonds that participate in bacterio rhodopsin function. Changes in H bonding of Asp85, Asp96, the Schiff base, and internal water molecules around these residues upon the formation of the L, M, and N photo intermediates of bacteriorhodopsin were investigated by difference FTIR spectroscopy. The locations and the interactio...

Dissolution of gallstones consisting of cholesterol, calcium carbonate, or calcium phosphate in different solvents left an amorphous organic gel-like substance (the matrix). Matrix from cholesterol stones could be colourless but was usually orange, yellow, or brown while that from calcium carbonate and calcium phosphate stones was almost invariably coloured black or dark brown. These pigments w...

Background: There is a growing demand for mass production of shikalkin (a natural pigment consisted of shikonin and alkannin) due to its increasing applications in cosmetics, pharmaceutical and nutrition industries. The root of Iranian Arnebia euchroma produces shikalkin. The promising capability of this plant for shikalkin production has already been demonstrated in cell culture studies. Obje...

The present study is designed to evaluate the application of a simple method for rapid identification of Malassezia furfur among other Malassezia spp. based on production of a brownish-red pigment and its diffusion into the medium containing L-tryptophan as a sigle source of nitrogen.  91 strains of Malassezia (20% M. furfur, 2% M. sympodialis, 5% M. obtosa and 73% M. globosa) isolated from ski...

The bogs in Northern Michigan are unusual ecosystems that contain a thick layer of peat that separates the surface vegetation from the nutrient-rich groundwater below it. Because of the thick layer of peat, nutrient-poor rain is the sole source of water for the surface vegetation, which allows the bog to stay nutrient-poor. In order to measure nutrient dynamics throughout bogs, we decided to in...

Avian eggshells are variedly coloured, yet only two pigments, biliverdin and protoporphyrin IX, are known to contribute to the dramatic diversity of their colours. By contrast, the contributions of structural or other chemical components of the eggshell are poorly understood. For example, unpigmented eggshells, which appear white to the human eye, vary in their ultraviolet (UV) reflectance, whi...

Species richness is one of the best indicators of biodiversity. However, there are few investigations on concordance of diversity patterns and environmental settings for marine regions. The objectives of this study were to correlate species richness of shallow water (< 200 m deep) sea stars with key oceanographic factors in the Gulf of California, México, and to predict species richness of Aste...

The ratio of cellular nitrogen and chlorophyll has been studied in cultures of marine phytoplankton during and after recovery from nitrogen deficiency. The time factors were observed to vary together; however, the ratio was only constant when the cells were sufficient in nitrogen. Since nitrogen deficiency produced chlorotic cells in all species studied, the degree of deficiency could be ascert...

Duerre, John A. (University of North Dakota, Grand Forks), and Patrick J. Buckley. Pigment production from tryptophan by an Achromobacter species. J. Bacteriol. 90:1686-1691. 1965.-A microorganism was isolated from the soil near the University of North Dakota. Biochemical and morphological characteristics indicated that this organism would best be classified as a member of the family Achromobac...

background and objectives: safflower (carthamus tinctorious l.) florets contain valuable red and yellow pigments and are used in food, textile dying, and pharmaceutical industries. red carthamine pigment is formed from a yellow precursor, precarthamine, through an oxidation reaction at the end of flowers' maturation stage. the present study was conducted to find out the most effective procedure...