We present results from transient absorption spectroscopy on a series of artificial light-harvesting dyads made up of a zinc phthalocyanine (Pc) covalently linked to carotenoids with 9, 10, or 11 conjugated carbon-carbon double bonds, referred to as dyads 1, 2, and 3, respectively. We assessed the energy transfer and excited-state deactivation pathways following excitation of the strongly allow...

Carotenoid-based sexual traits are thought to be reliable indicators of male quality because they might be scarce and therefore might indicate the ability of males to gather high-quality food and because they are involved in important physiological functions (as immune enhancers and antioxidants). We performed an experiment where male and female zebra finches (Taeniopygia guttata) were provided...

A fractional factorial design 2(5-1) was used to evaluate the effect of temperature, pH, and concentrations of yeast extract, tryptone and Nitsch's trace elements on the biomass, total carotenoids and protection against singlet oxygen by carotenoid extracts of the bacterium Thermus filiformis. In addition, the carotenoid composition was determined by high-performance liquid chromatography conne...

Sequential statistical methods were used to maximise carotenoid production by a strain of Rhodotorula mucilaginosa, isolated from the Brazilian ecosystem. Initially, a factorial 2(5-1) experimental design was used, and the variables were pH and the levels of glucose, yeast extract, MgSO4.7H2O and KH2PO4. The nitrogen source (yeast extract) was the most important variable in enhancing carotenoid...

Carotenoid pigments have become a central subject of research on animal signaling systems during the past decade. Thus, measurement of plasma carotenoid levels is widespread in the literature. Many plasma biochemical parameters tend to vary with the hour of sampling, which may be an important source of sampling error. However, little is known about this kind of variation for circulating caroten...

To determine whether Saccharomyces cerevisiae can serve as a host for efficient carotenoid and especially beta-carotene production, carotenogenic genes from the carotenoid-producing yeast Xanthophyllomyces dendrorhous were introduced and overexpressed in S. cerevisiae. Because overexpression of these genes from an episomal expression vector resulted in unstable strains, the genes were integrate...

Plant carotenoids have a key role in preventing various diseases in human because of their antioxidant and provitamin A properties. Chickpea is a good source of carotenoid among legumes and its diverse germplasm and genome accessibility makes it a good model for carotenogenesis studies. The structure, location, and copy numbers of genes involved in carotenoid biosynthesis were retrieved from th...

Carotenoids are organic pigments that are produced predominantly by photosynthetic organisms and provide antioxidant activity to a wide variety of plants, animals, bacteria, and fungi. The carotenoid biosynthetic pathway is highly conserved in plants and occurs mostly in chromoplasts and chloroplasts. Leaf carotenoids play important photoprotective roles and targeted selection for leaf caroteno...

Vertebrates cannot synthesize carotenoid pigments de novo, so to produce carotenoid-based coloration they must ingest carotenoids. Most songbirds that deposit red carotenoids in feathers, bills, eyes, or skin ingest only yellow or orange dietary pigments, which they oxidize to red pigments via a ketolation reaction. It has been hypothesized that carotenoid ketolation occurs in the liver of vert...

This study was conducted to evaluate the effects of diets containing 0, 100, 200 and 300 mg of carotenoid/kg diet from marigold meal on skin pigmentation, growth, feed utilization and survival of goldfish (Carassius auratus), with average initial weight of 1.8 g for a rearing period of 63 days. The pigmentation degree in skin of goldfish increased significantly with increasing inclusion of mari...