Carotene-bleaching activities of lipoxygenase and heme proteins as studied by a direct spectrophotometric method

Optimized Formation of Detergent Micelles of β-Carotene and Retinal Production Using Recombinant Human β,β-Carotene 15,15'-Monooxygenase

“…These micelles are solubilized under aqueous conditions and are absorbed by intestinal cells (1)(2)(3)(4)(5)(6). Moreover, detergent micelles of -carotene have been used in the conversion of -carotene to retinal under aqueous conditions (4,10,(14)(15)(16)(17)(18)(19)(20). Thus, we investigated the effect of factors such as solvent, detergent, and substrate on the formation of detergent micelles of -carotene for retinal production under aqueous conditions.…”

“…However, because these micelles were used to investigate enzyme characterization other than retinal production, only a small amount of -carotene was used (4,10,(14)(15)(16)(17)(18)(19)(20).…”

Scavenging of Nitrogen Dioxide, Thiyl, and Sulfonyl Free Radicals by the Nutritional Antioxidant ²-Carotene

“…Solutions were prepared immediately before experimentation using purified water from a Milli-Q system (Millipore). Solutions required for pulse radiolysis experiments contained no more than 20 mol dm Ϫ3 ␤-carotene to allow adequate light transmission in the 300 -500 nm region, where ␤-carotene exhibits a strong ground-state absorption (59). Before irradiation solutions were bubbled with nitrous oxide (N 2 O, oxygen content Ͻ 10 ppm) or with nitrogen (N 2 , oxygen content Ͻ 10 ppm) from the British Oxygen Co., United Kingdom.…”

Determination of the Activity of Lipoxygenase (Lipoxidase)

“…In 1970 Ben Aziz et al (86) described a direct spectrophotometric method for studying the carotene bleaching activities of lipoxygenase and heme proteins in aqueous solution. They used Tween 80 for bringing linoleate and carotene into aqueous solution so that the disappearance of carotene could be followed continuously.…”

“…They used Tween 80 for bringing linoleate and carotene into aqueous solution so that the disappearance of carotene could be followed continuously. The method, which is detailed below, was successfully applied to a study of linoleate and carotene-oxidizing fractions of alfalfa (8,24,47,48,52), and the catalytic effects of lipoxygenase, cytochrome c, and peroxidase on the bleaching of carotene in the presence of unsaturated fatty acids have been compared (86).…”