Anthocyanins from purple sweet potatoes can serve as natural colorants due to their high heat and light stability and are commonly used in juices, alcoholic beverages, jams, confectioneries, bread, snacks and noodles. There are several commercially available varieties of purple sweet potatoes, which can vary in storage root size, shape, and color. During the last decade sweet potato cultivars w...

The dogwhelk is a rocky intertidal gastropod of the North Nucella lapillus Atlantic coast. Individual shell color varies. Common colors range between white and brown, with darker dogwhelks being more affected by heat stress than lighter-colored conspecifics. Other reported shell colors are purple, black, mauve, pink, yellow, and orange from UK coasts, red and gray from the Bay of Fundy coast of...

There is a relative absence of studies dealing with mats of purple sulphur bacteria in the intertidal zone. These bacteria display an array of metabolic pathways that allow them to disperse and develop under a wide variety of conditions, making these mats important in terms of ecosystem processes and functions. Mass blooms of purple sulphur bacteria develop during summer on sediments in the int...

1. Carotenoids have been identified and their quantities measured in the eyes of several frog species. The combined pigment epithelium and choroid layer of an R. pipiens or esculenta eye contain about 1gamma of xanthophyll and about 4gamma of vitamin A. During light adaptation the xanthophyll content falls 10 to 20 per cent. 2. Light adapted retinas contain about 0.2-0.3 gamma of vitamin A alon...

The purple membrane ofHalobacterium halobium contains a single protein known as bacteriorhodopsin, which is composed of 1 mol retinal]mol bacterio-opsin [ 1 ]. The organization of the protein within each purple membrane sheet is that of an exact 2-dimensional crystal. X-ray and electron diffraction data have revealed that the bacteriorhodopsin in purple membrane is arranged as trimeric units in...

The purple leaf pigmentation mainly associated with anthocyanins accumulation is common in Brassica but the mechanisms of its production and its potential physiological functions are poorly understood. Here, we performed the phenotypic, cytological, physiological, and comparative leaves transcriptome analyses of 11 different varieties belonging to five Brassica species with purple or green leav...

Field assays were performed to determine the optimal color for Agrilus planipennis Fairmaire (Coleoptera: Buprestidae) traps. Previous studies have found that more A. planipennis are caught on purple or green traps than traps of other colors. In three studies, we evaluated various shades of purple, wavelengths of green (500-570 nm), and greens of different reflectance (from 9 to 66%). In all te...

The classical absorption spectrum of visual purple (KSttgen and Abelsdorff, 1896) is the difference in photometric density (log Io/I) at different wave-lengths between a solution in its unbleached and its bleached condition. The reason for this procedure is that extracts of visual purple are not pure but contain other substances which may be colored. The resulting classical subtraction curve is...

The filamentous green alga Zygogonium ericetorum (Zygnematophyceae, Streptophyta) was collected in a high-alpine rivulet in Tyrol, Austria. Two different morphotypes of this alga were found: a purple morph with a visible purple vacuolar content and a green morph lacking this coloration. These morphotypes were compared with respect to their secondary metabolites, ultrastructure, and ecophysiolog...