BACKGROUND As a potent antimicrobial agent, silver nanostructures have been used in nanosensors and nanomaterial-based assays for the detection of food relevant analytes such as organic molecules, aroma, chemical contaminants, gases and food borne pathogens. In addition silver based nanocomposites act as an antimicrobial for food packaging materials. In this prospective, the food grade melanin ...

INCE the very early experiments of GRAUBARD (1933), numerous investigators have examined the problem of genetic control of phenol oxidases in Drosophila with attention focused primarily on pigment production and thus on the color mutants. However, it has become clear that the function of such enzymes in cuticle formation is far more vital than in pigment production. It follows that if the same ...

Melastoma malabathricum, belongs to the Melastomaceae family, is an important medicinal plant widely distributed from Madagascar to Australia, that is used in traditional remedies for the treatment of various ailments. Besides its medicinal properties, it has been identified as a potential source of anthocyanin production. The present study was carried out to investigate the effect of sucrose a...

A B ST RACT Visual pigment bleaching desensitizes rod photoreceptors greatly in excess of that due to loss of quantum catch. Whether this phenomenon also occurs in cone photoreceptors was investigated for isolated salamander red-sensitive cones. In parallel experiments, (a) visual pigment depletion by steps of bleaching light was measured by microspectrophotometry, and (b) flash sensitivity was...

Visual pigment bleaching desensitizes rod photoreceptors greatly in excess of that due to loss of quantum catch. Whether this phenomenon also occurs in cone photoreceptors was investigated for isolated salamander red-sensitive cones. In parallel experiments, (a) visual pigment depletion by steps of bleaching light was measured by microspectrophotometry, and (b) flash sensitivity was measured by...

Lemberg (1935) first showed that the green haemin of Warburg & Negelein (1930), on treatment with methanolic hydrogen chloride, gave a ferric salt of a biliverdin ester from which the ester of biliverdin itself could be obtained by shaking the chloroform solution of the salt with water. Lemberg concluded that green haemin possessed the structure of a verdohaemochromogen, i.e. it possessed an op...

The distal pigment cells of Orconectes limosus contain two layers of large electron lucent vacuoles that are separated by layers of small right-angled platelets adjacent to the crystalline cones. The crystalline cones of the dioptric apparatus of this species have evaginations into the distal pigment cell cytoplasm. In photoreceptors of Orconectes limosus and Procambarus clarkii a dark pigment ...

SYNOPSIS. Integumental color changes and eye pigment movements in crustaceans are regulated by pigmentary-effector hormones. The identified hormones include: an octapeptide RPCH (red pigment-concentrating hormone) and several forms of octadecapeptide PDH (pigment-dispersing hormone: a-PDH, b-PDH). RPCH-related peptides (AKHs, adipokinetic hormones) and PDH-related peptides (PDFs, pigment-disper...

RATIONALE  Choroidal neovascular (CNV) lesions in younger patients are often accompanied by the appearance of a surrounding ring of pigment that is associated with disease regression or slowed disease progression. In older patients with age-related macular degeneration (AMD), however, hypertrophy of the retinal pigment epithelium (RPE) is known to occur but has not previously been reported to b...

The refined structure of the peripheral light-harvesting complex from Rhodopseudomonas acidophila strain 10050 reveals a membrane protein with protein-protein interactions in the trans-membrane region exclusively of a van der Waals nature. The dominant factors in the formation of the complex appear to be extramembranous hydrogen bonds (suggesting that each apoprotein must achieve a fold close t...