ß -carotene is a human nutrient found in plants or animals. It is also can be synthesized chemically. It is lipid-soluble, and is yellow, orange or red in color. ß-Carotene can be cleaved into vitamin A in vivo. The most abundant form of ß-carotene in human serum is trans isomer; cis isomers such as 9-cis ß-carotene, 13-cis ß-carotene, and 15-cis ß-carotene are only present in trace amounts. ß-...

Beta-carotene (ß-carotene) is one of many carotenoids found in nature. In the human nutrition field, evidence suggests that higher blood levels of ß-carotene as well as other carotenoids such as alpha-carotene, lycopene, lutein, zeaxanthin, and ß-cryptoxanthin may be associated with lower risk of several chronic diseases. ß-carotene, a-carotene, and ß-cryptoxanthin have pro-vitamin A activity, ...

ß-Carotene is present in extremely high concentrations in bovine corpus luteum. The aim of this study was to examine the extent of the seasonal variation in concentrations of luteal ß-carotene in cows. A total of 102 corpora lutea collected throughout all 12 months of the year were analysed by high performance liquid chromatography (HPLC). The mean ß-carotene concentration of the luteal tissues...

Carotenoids, Metabolism, [14C]/?-Carotene, Insects, Carausius morosus [14C]/?-Carotene was fed to juvenile stick insects, Carausius morosus, o f the fifth instar. Radio­ activity was incorporated into 2-hydroxy-, 2-oxo-, and 3,4-didehydro-2-oxo-carotenoids of the ß,ß-type. These transformations are due to the insect’s own capacity; any contribution by microbial symbionts can be ruled out. A stu...

2-Oxo-carotenoids, 2-Hydroxy-carotenoids, [uC]/?-Carotene, Metabolism, Stick Insects The carotenoids of the stick insect, Ectatosoma tiaratum, were studied by spectroscopic and chemical methods. The /?,/?-type pigments are /?,/?-carotene, /?,/?-caroten-2-one, /?,/?-caroten-2-ol, /?,/?-carotene-2,2'-dione, 2'-hydroxy-/?,/?-caroten-2-one, ß,^-carotene-2,2'-diol, 3,4-didehydro-/?,/?carotene-2,2'-d...

When the sub-core complex of photosystem II, D1/D2, is irradiated at 436 or 415 nm (absorption by chlorophyll and pheophytin and ß-carotene) or 540 nm (absorption primarily by pheophytin), the low temperature fluorescence spectrum has two maxima, at 685 and 674 nm. This shows the existence of at least two different fluorescent forms of chlorophyll (chlorophyll a and perhaps pheophytin a). When ...

Delayed light emission (DLE) from aggregated chlorophyll is used to probe energy transfer between aggre­ gated chlorophyll and ß-carotene. Preilluminated ßcarotene when injected into a dark chamber containing aggregated chlorophyll, induces DLE from aggregated chlorophyll. If the dark chamber contains only monomeric chlorophyll, there is no DLE. The intensity of DLE is de­ pendent on the time o...

Z. Naturforsch. 44c, 959—965 (1989); received April 19, 1989 ß-Carotene-5,6-epoxide, Photooxidation, DCMU, Carotenoids The occurrence of ß-carotene-5,6-epoxide in higher plant photosynthetic tissue is described. The compound is found in isolated chloroplasts, thylakoids and other subchloroplast particles but can only be detected in intact leaves or cotyledons of higher plants when these are exp...

The aim of the study was to evaluate oxidative stress in cows undergoing normal parturition and cows suffering from dystocia. The erythrocytic glutathione peroxidase (GSH-Px) activity, plasma vitamin A and ß-carotene concentrations, and paraoxonase PON1 activity were lowered (P<0.001, P<0.01, 0.05, and 0.05, respectively) in cows with dystocia compared to normal calving cows. The erythrocytic m...

The carbon flow from 3-phosphoglycerate to pyruvate and acetyl-CoA within the chloroplast as well as the pathway for the formation of ß-carotene, plastoquinone-9 etc. as plastidic isoprenoids from photosynthetically fixed C 0 2 hitherto remained unclear because the presence of the phos­ phoglycerate mutase in chloroplasts had not unequivocally been proven. To clarify this question, the incorpor...