background and objective: pigment production by microorganisms is important due to more rapid growth, higher efficiency, easier extraction, and antimicrobial effects compared to other methods. the aim of the present study is to isolate and identify antibiotic pigment-producing actinomycetes from the soil of the persian gulf and to evaluate the antibiotic activity of their pigments in the second...

abstract background: transpupillary thermotherapy is a new treatment for subfoveal choroidal neovascularization which needs further evaluation. this study was aimed to evaluate the efficacy of transpupillary thermotherapy on regression of occult subfoveal choroidal neovascularization with or without pigment epithelial detachment in patients with age-related macular degeneration. methods: in a c...

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. objec...

sodium bentonite can bind to dietary pigment and decreases yolk color scale. sodium bentonite is one of the main parts of formycine® gold, the effect of different levels of formycine® gold and dietary pigment on egg quality, egg yolk color and performance criteria of laying hens from 26 to 34 week of age were studied. one hundred ninety two hy-line hens were divided into 24 groups of 8 birds ea...

Sodium bentonite can bind to dietary pigment and decreases yolk color scale. Sodium bentonite is one of the main parts of Formycine® Gold, the effect of different levels of Formycine® Gold and dietary pigment on egg quality, egg yolk color and performance criteria of laying hens from 26 to 34 week of age were studied. One hundred ninety two Hy-Line hens were divided into 24 groups of 8 birds ea...

he fluorescence yield of chlorophyll a in dark adapted Anacystis nidulans undergoes a slow change with continuous illumination. After the completion of the initial fast transient, the fluorescence yield rises from the level S to a plateau M within a minute, declining only after prolonged illumination. Both normal and 1,1-dimethyl-3(3'4'-dichloro)-phenylurea (DCMU)-poisoned Anacystis are capable...

Age-related macular degeneration, a major cause of blindness for which no satisfactory treatments exist, leads to a gradual decrease in central high acuity vision. The accumulation of fluorescent materials, called lipofuscin, in retinal pigment epithelial cells of the aging retina is most pronounced in the macula. One of the fluorophores of retinal pigment epithelial lipofuscin has been charact...

Melanin is nearly a ubiquitous pigment synthesized by living organisms in the course of hydroxylation and polymerization of organic compounds. Melanins have immense application potentials in the field of agriculture, cosmetics and pharmaceutical industries (photoprotection and mosquitocidal activity isolated from Streptomycete). In this study, the halophilic black yeast, Hortaea werneckii produ...

Measurements of downwelling spectral irradiance were made during the fall of 1982 in the North Pacific Ocean (near 33øN, 142øW). These data are used to produce vertical profiles of downwelling irradiance for visible energy (400-700 nm) and photosynthetic available radiation (PAR). The profiles demonstrate that the attenuation of visible energy and PAR are primarily functions of chlorophyll pigm...

(1) The spectral sensitivity function for the compound eye of the crayfish has been determined by recording the retinal action potentials elicited by monochromatic stimuli. Its peak lies at approximately 570 mmicro. (2) Similar measurements made on lobster eyes yield functions with maxima in the region of 520 to 525 mmicro, which agree well with the absorption spectrum of lobster rhodopsin if m...