Talk:Carotenoid

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Chemicals (Rated Start-class, Mid-importance)
WikiProject icon This article is within the scope of WikiProject Chemicals, a daughter project of WikiProject Chemistry, which aims to improve Wikipedia's coverage of chemicals. To participate, help improve this article or visit the project page for details on the project.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 Mid  This article has been rated as Mid-importance on the project's importance scale.
 
WikiProject Molecular and Cellular Biology (Rated Start-class, High-importance)
WikiProject icon This article is within the scope of the WikiProject Molecular and Cellular Biology. To participate, visit the WikiProject for more information.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 High  This article has been rated as High-importance on the project's importance scale.
 
WikiProject Plants (Rated Start-class, Mid-importance)
WikiProject icon This article is within the scope of WikiProject Plants, a collaborative effort to improve the coverage of plants and botany on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 Mid  This article has been rated as Mid-importance on the project's importance scale.
 

Structure[edit]

Shouldn't there be a picture with the structure of the carotenoids up there? 71.245.246.18 02:17, 5 April 2006 (UTC)

600 known carotenoids? I can't find that many on this site. Twilight Realm 01:20, 6 January 2006 (UTC)

Redshift[edit]

Won't a red shift in absorbtion make the apparent color more blue? I don't see how absorbing more red will make the molecule appear more red. Brianf711 19:04, 20 February 2006 (UTC)

Template help[edit]

If anyone has time, the {{Carotenoids}} template would really benefit from your expertise. Thanks! :) Willow 19:09, 27 January 2007 (UTC)

Synthesis in Corpus Luteum[edit]

It's not completely true that carotenoids cannot be synthesized in animals. Beta-carotene can be synthesized from acetyl-CoA and mevalonate in the corpus luteum (Gawienowski AM. Integration of the Metabolic Pathways of Steroids, Carotenoids and Retinoids. Critical Reviews in Biochemistry and Molecular Biology. 34(6):405-410 (1999)). Icek 14:53, 24 July 2007 (UTC)

Sorry, but although there exists a 1968 paper claiming to detect beta-carotene synthesis in in vitro bovine corpus luteum tissue slices, from radiolabeled acetate, careful attempts to replicate this have failed: see [1]. Moreover, there is independent reason not to believe it, since what would keep such beta carotene from difussing out of the corpus luteum, being metabolized in various tissues by dioxygenase, and allowing cows to make their own vitamin A (meaning that they'd have no vitamin A requirement?). Mammals can make squalene and there are strong evolutionary pressures for them to go on an make vitamin A (particularly vegetarian animals) but so far as we can tell, none of them can do it. SBHarris 22:36, 30 April 2010 (UTC)

Lead[edit]

I've added that carotenoids are also found in chloroplasts which has made the lead a little bit tricky to read. Shouldn't there be some mention of B-carotene being in animals too? The above post also seems to fit with this. Smartse (talk) 16:41, 27 May 2009 (UTC)

Synthesis in aphids[edit]

I added that carotenoids are synthesized by Aphids, as per Science 328 (5978), 624. DOI: 10.1126/science.1187113 idoerg

You should have added the reference, too, but I did it for you. Nice addition, and a very cool finding for science. And people worry about genetic engineering for animals in the wild. I suppose these Franken-aphids will now be as scary to the Greenpeace as Golden rice. SBHarris 17:19, 30 April 2010 (UTC)

I actually added the reference, but further down in the text body (ref #10) so now we have refs #1 and #10 to the Moran paper which are identical. Any way to consolidate that? I like it that your added reference is on top, but by wikipedia-foo is not strong enough to put the same reference tag in the text body (scroll down).

Done. Have a nice day.—Tetracube (talk) 19:57, 30 April 2010 (UTC)
Thanks, Tetracube! SBHarris 22:01, 30 April 2010 (UTC)

Black tea[edit]

Some studies on carotenoids and their degradation in black tea manufacture may be of interest - Says violaxanthine and neoxanthine are important. Rod57 (talk) 03:12, 23 September 2010 (UTC)

Dietary carotenoids[edit]

Lutein and Zeaxanthin; An Introduction to the Chemistry of Dietary Carotenoids looks interesting - nice images, and diagram ordering by anti-oxidant activity. Rod57 (talk) 23:52, 7 December 2010 (UTC)

An excellent article. Too bad we can't just copy the illustrations! As for "anti-oxidant" activity, this article makes one of many points, which is that there's no such "thing" on a simple scale. The xanthophyll carotenoids (astaxanthin, zeaxanthin, etc) are far better at de-quenching singlet oxygen, which is why they are made in such abundance by plants. While the carotene carotenoids (lycopene, beta-carotene, etc) make better sacrificial free-radical targets. These things have very different lives in the excited state, also, and this is influenced strongly by their hydrophobicity, which in turn is a function of their oxygen content also. Probably it takes all kinds to do a lot of things, healthwise. The people who advocate a wide spectrum of whole-food fruits and vegetables are not so dumb. Particularly with the recent disasters in attempts at supplementing beta carotene to smokers and others at cancer risk. SBHarris 18:43, 15 September 2011 (UTC)