Talk:Chlorophyll

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edit·history·watch·refresh Stock post message.svg To-do list for Chlorophyll:

Here are some tasks awaiting attention:
  • Expand: Include a section on the health benefits of chlorophyll.

Anthon01 14:02, 1 November 2007 (UTC)

Introduction[edit]

"more commonly known as boraphyll"

I'm no botanist, but I simply don't believe this. Google returns 258 hits for boraphyll, 5,820,000 for chlorophyll.

Please will someone knowledgeable review this and correct it?

Thanks.

132.244.246.25 11:18, 18 December 2006 (UTC)

haha, that's vandalism. it's a joke from the movie Billie Madison in which Adam Sandler interrupts a high-school science class by saying "Chlorophyll? more like bore-ophyll!"

Diagram[edit]

Common structure of chlorophyll a, b and d
Common structure of chlorophyll c1, and c2

This diagram isn't right - the phytyl chain doesn't have enough carbon atoms. Less importantly, it would be nice if it showed all the different varieties of chlorophyll. I don't really have the tools to correct it at the moment, plus I don't know what font is being used. See [1], [2]. Josh

Okay, there's an updated a & b. Yes, at least a c might be nice to have too, to illustrate one without the tail, will look into it. It would probably be overkill to show variations like bacteriochloropyll, though. iMeowbot~Mw 16:38, 13 Feb 2005 (UTC)
All right, it's got d in there too, on to the c's! iMeowbot~Mw 20:35, 13 Feb 2005 (UTC)
Okay then! there's c1 and c2. If someone could do a sanity check, that would rule. The numbers and bonds appear okay from here, but hey, things happen. iMeowbot~Mw 22:14, 13 Feb 2005 (UTC)

Those look really nice. I've added them to the page. Bacteriochlorophylls would, of course, go on the bacteriochlorophyll page, but that's less important. Josh

Didn't even think to look for a separate article, duh, thanks --iMeowbot~Mw 12:15, 18 Feb 2005 (UTC)
Don't some of the "varieites" need an extra carbon atom? ie. the pink box, should be a methyl gropu for a,d but the bonds should look like a + as opposed to a T .. 203.218.141.233 13:55, 1 March 2006 (UTC)

Agreed this article needs to be fixed — Preceding unsigned comment added by Duckoducko2 (talkcontribs) 01:12, 14 March 2013 (UTC)

Additional images[edit]

I'm not sure what you are looking for. There are images of structure diagrams for several chlorophylls at the PubChem website. [3]


chlorophyll a

The absorbance graph is wrong. The Chl a spectrum is correct but the Chl b spectrum marked in red is not correct. The absorption peak for Chl b is at 647 nm! The spectrum shown in red is for a Chl c compound, either Chl c1, Chl c2, a mixture of the two Chl c1c2 or Mg-DVP (a Chl c found in some organisms) which all peak at 630 nm.

Absorbance graph[edit]

The plots look sane, but they're unreferenced so I intend to redo with a documented set of published numbers. I have numbers for a and b; does anyone know of nice clean series for the c or d floating around on the net? iMeowbot~Mw 23:42, 13 Feb 2005 (UTC)

Next two absorbance spectrum is very different. Second graph has high absorbtion in green. Dont look slightly modified. What is it?
1 — Absorption maxima of chlorophylls against the spectrum of white light.
2 — Absorbance spectra of free chlorophyll a (green) and b (red) in a solvent. The spectra of chlorophyll molecules are slightly modified in vivo depending on specific pigment-protein interactions.

Questions that could be addressed for this article[edit]

I have several questions that perhaps someone could address in this article. What is the importance of the Mg in chlorophyll? What does it enable and how is this important to the plant? What makes a particular pigment efficient at absorbing a certain wavelength, what property distinguishes it from the other pigments?

Can someone also address the health benefits of chlorophyll and it's similarity to human red blood cell? we contain iron where chlorophyll contains magnesium. The preceding unsigned comment was added by 69.155.183.69 (talk • contribs) .

Do you mean it similarity to porphyrin in hemoglobin? These are good questions. David D. (Talk) 08:28, 5 January 2006 (UTC)


Is there some reason why the green part of the visible spectrum is not absorbed by chlorophyll and associated pigments? Why is chlorophyll able to absorb only red and blue light? Would a more efficient system absorb all visible light?

Where can I find the answers to these questions?

I placed you questions on the science ref desk. You can find any replies to your questions here Wikipedia:Reference_desk/Science#Chlorophyll_efficiency. David D. (Talk) 16:14, 1 February 2007 (UTC)

I've got another question, or suggestion: who discovered chlorophyll was necessary for photosynthesis? I've heard it was Rene Dutrochet, but I can't source it. Can somebody confirm & include? Trekphiler 23:06, 3 February 2007 (UTC)

Healthy?[edit]

Is chlorophyll healthy to humans, particularly when ingested? JIP | Talk 17:59, 12 March 2006 (UTC)

Chlorophyll and it's derivatives have been widely investigated for a range of beneficial biological activities. Seems like the health benefits of clorophyll should be included in this article.

"Biological activities attributed to chlorophyll derivatives consistent with cancer prevention include antioxidant and antimutagenic activity, mutagen trapping, modulation of xenobiotic metabolism, and induction of apoptosis." from Digestion, absorption, and cancer preventative activity of dietary chlorophyll derivatives Anthon01 14:01, 1 November 2007 (UTC)

Anthon01 04:55, 2 November 2007 (UTC)

Well, oliveoilsource says in its color section in chemical properties of olive oil that the colør of olive oil, partly caused by chlorophyll, doesn't change how healthy it is. It also says spinach contains much more chlorophyll, so I think it might be healthy to humans. Does chlorophyll have a taste? If not, why isn't it used as a coloring agent?

Partly because it isn't stable enough. More importantly, it isn't very soluble in water because of the hydrophyllic tail, and isn't fully soluble in oil because of the porphyrin ring. As a result, other more easily dissolved compounds are used. --EncycloPetey (talk) 21:57, 11 February 2008 (UTC)

Chemical properties[edit]

Hi, could an article with the chemical properties of chlorophyll be created? Like how there is Vitamin C and Ascorbic acid as well as Water and Water (molecule). I came here to find out the temperature chlorophyll decomposes at (if its the same as proteins), and any other reasons why it goes brown. thoughts? mastodon 17:05, 23 May 2006 (UTC)

Chlorophyll a spectra[edit]

The Chlorophyll a absorption maximum at 680 nm looks a little bit tight, i think. The Soret bands look ok. As there is an unequally spaced division of the x coordinate, could it be, the somehow log scale and linear scale got mixed up?

Stefan

Chlorophyll Spectra[edit]

The chlorophyll b spectrum is still wrong. Chl b has a red absorption peak at about 645 - 652 nm depending on the solvent. The spectrum marked Chl b is more likely to be chlorophyll c1 or c2. Please fix it.

Ray Ritchie —The preceding unsigned comment was added by Raymond J. RITCHIE (talkcontribs) 08:26, 5 January 2007 (UTC).

Article needs subheadings[edit]

I think the article is in desperate need of subheadings. Any good review article is separated out into topics to aid in understanding the material. Unfortunately, I am not an expert on chlorophyll (I was checking this site for some study help), but someone more knowledgeable could really contribute by sorting out the facts into distinct topics. —The preceding unsigned comment was added by 216.133.94.29 (talk) 12:27, 1 May 2007 (UTC).

The structures shown are incorrect[edit]

Mg is not square planar in chlorophylls, it contains very strongly bonded water, although I dont know if it is two or one water per Mg2+.--Smokefoot 15:20, 17 June 2007 (UTC)

You are right square planar is a coordination not very likely if any oxygen containing compound is around.--Stone 09:32, 23 July 2007 (UTC)

History[edit]

The ground breaking works of Willstätter should be mentioned in a history section, togeter with the work of the other chemists who tried to determin the structure of Chlorophyll at the turn of the century. Richard Willstätter (1915). "The Chlorophyll". Journal of the American Chemical Society 37 (2): 323 – 345. doi:10.1021/ja02271a011. --Stone 09:32, 23 July 2007 (UTC)

Spectral characterization of chlorophyll[edit]

  • Despite the great extent of information contained in this article, I found it was missing what for me are the most important values: Namely the absorption maxima for chlorophyll a and b, and proper citing of sources for specific values. I am not a chemist, I am an electronic technician and thus more interested in the implications of this data for building LED grow lights. If I f-up something chemistry related please comment.--Phillipbeynon 23:30, 1 August 2007 (UTC)

Once again - every structure shown is incorrect![edit]

Wonderful that this important topic is nominated for greater exposure, but all of the structures are incorrect (including the one shown above). It may be inconvenient, but Mg2+ is not square planar.--Smokefoot 02:01, 18 September 2007 (UTC)

OK, I have put up new structures, pretty much cribbed from PubChem. They might not be as attractive as the one above, but they have the following advantages:
  • They don't have all those irritating H-atoms all over the place
  • They are (as far as I can tell) correct
  • They are SVGs, so if they aren't correct, they're much easier to fix.
If you really like, you could even create one of those callout-type diagrams to represent the different forms. The diagrams I was working from give different double-bonds for the porphyrin ring structure for a and b, but as far as I can see, they're just equivalent resonance structures.
If I goofed, please let me know! --Slashme 16:49, 26 September 2007 (UTC)
Chlorophyll in vivo

I've made a ball-and-stick model of chlorophyll within a protein, with pentacoordinate Mg. The fifth coordination site is occupied by a histidine residue. The image is based on a PDB from this UOB page.

If anyone can find a paper or PDB on the crystal structure of isolated chlorophyll (an aqua complex, for example), I'll make images of it.

Perhaps the skeletal formulae and 3D images should be updated to show a fifth, unspecified ligand, for generality.

Ben 22:21, 26 September 2007 (UTC)

How, a dotted line pointing to an "X" with an explanation in the caption? --Slashme 14:34, 8 October 2007 (UTC)

Synthesis[edit]

I'm surprised that the chemical synthesis is not mentioned. This was one of Robert Burns Woodward's most famous targets! I know, WP:SOFIXIT, but I'm too lazy today. --Itub 11:31, 28 September 2007 (UTC)

Chlorophyll and human diet[edit]

I'm surprised that this article doesn't address this subject at all. You hear vague claims about the health benefits of chlorophyll, so it'd be nice to have some discussion of the actual research in the area. — Laura Scudder 03:04, 24 January 2008 (UTC)

Why would chlorophyll be any more good for you than eating lettuce or any other green plant? Your food all goes into the stomach are is broken down into the same molecules and absorbed or passed out the body? It can't be any thing more than expensive lettuce, I would think raw spinach would be better for you than Chlorophyll?. Hardyplants (talk) 06:02, 24 January 2008 (UTC)
This rather misses the point. The question is, is chlorophyll good for you, and if so how and why? Presumably if it is in fact a healthy component of a diet, that is true whether consumed as an isolate or as part of some spinach. As Laura says, people certainly make health claims for it. Is there any science anywhere to back it up, beyond this 1936 paper that reports some apparent benefits for anaemic rabbits, and a few papers on its use (or more commonly the use of chlorophyllin) in cancer treatment? If not, is it worth bringing it up just to say, well, people say it's good for you but there isn't really any science to back it up? It's intriguing that it's so chemically similar to haemoglobin - another point that I would've thought worth mentioning here in passing - and it's not absurd to imagine that one might be used to synthesise the other... but who knows? My Google Scholar skills are failing me here, I'm afraid. --Oolong (talk) 16:53, 17 October 2011 (UTC)

Chlorophyll is used in supplements for a variety of benefits. It possesses great antibacterial action, heals and repairs tissue, and increases circulation to the organs. It also serves as a blood purifier and detoxifier, as well as an internal deodorizer.

Possible Benefits

Increases circulation to the organs by dilating blood vessels Removes toxins and purifies blood Provides antibacterial action Promotes cellular health Acts as an internal deodorizer Helps the liver build red blood cells Relieves constipation and soothes stomach ailments

Usage Guidelines There is no established RDA for Chlorophyll and no known side effects. —Preceding unsigned comment added by 71.124.131.5 (talk) 02:53, 28 April 2008 (UTC)

That's great, but it's completely unsourced. As an anonymous claim without documentation, it has no value. --EncycloPetey (talk) 04:07, 28 April 2008 (UTC)

Merge Chlorosis here[edit]

Merge The Chlorosis article is very short. It is a condition usually caused by a nutrient deficiency that disrupts the biosynthesis of chlorophyll, and so closely overlaps with the biosynthesis section that ought to be in the Chlorophyll article. --EncycloPetey (talk) 04:50, 8 February 2008 (UTC)

Do you think there will be more info added to this page on chlorophyll? The Chlorosis topic would/should be much larger than it is now. I have no objection to the merge - but the chlorosis section would dominate the page (except for the large pictures already here). Hardyplants (talk) 22:58, 8 February 2008 (UTC)
It would only dominate the page temporarily. There is a lot of information still to be added about chlorophyll. --EncycloPetey (talk) 04:43, 9 February 2008 (UTC)
If you merge the two pages, I will work on the Chlorosis part. As a side note, the picture on that page is not really an example of chlorosis but of albinism, a common condition in some plants seedlings, it is nearly always a fatal condition- though there are some plants that later on develop enough chloroplasts to "survive". There is in fact some named Hosta cultivars that come out all white and later in growing season develop some green streaking. These are maternally derived pigments and during celliar division not all the seedlings receive the pigments. Hardyplants (talk) 20:21, 9 February 2008 (UTC)

Oppose I don't think it would be a good idea to merge chlorosis - an article on a plant disease - with an article on chlorophyll, which is much wider in scope. (To be perfectly honest, I'm surprised to see that this article is so relatively short at the moment!) I just added some viticultural aspects to the chlorosis article, and I don't really see that info belonging in the general chlorophyll article, but I do think they belong where they are! Tomas e (talk) 17:07, 4 May 2008 (UTC)

Oppose I arrived here after looking up "chlorosis," which I suspected my beans and tomatoes have, and to find its remedy. I would not have looked in "chlorophyll." By the way, don't I remember there is a Chlorophyll A and B? What about subtypes, algae and chlorophyll-producing bacteria and so on? Lots of good stuff left out, and no reason to merge chlorosis just to make this article look better. Just link to it. —Preceding unsigned comment added by Deopressoliber (talkcontribs) 13:43, 6 September 2008 (UTC)

Oppose The Chlorosis article would have specific info about causes/treatments/susceptability.. Since it has also been expanded since February, I'm going to remove the merge notice. eug (talk) 10:10, 21 December 2008 (UTC)

Color[edit]

What is the exact color of chlorophyll (all types)? Press olive, win oil (talk) 21:13, 11 February 2008 (UTC)

That is indicated by the absorption spectrum in the article. The light wavelengths not absorbed will be reflected, giving the compound color. In this case, chlorophyll is green, as indicated in the outset of the article. --EncycloPetey (talk) 21:54, 11 February 2008 (UTC)

Yes, it's green all right, but how about a color space please? Press olive, win oil (talk) 20:36, 15 February 2008 (UTC)

You can see the wavelengths of absorption in the graph in the article. --EncycloPetey (talk) 22:59, 15 February 2008 (UTC)

Some discussion on the fluorescence of chlorophyll would be interesting. (130.207.218.197 (talk) 15:02, 25 September 2012 (UTC))

Why oh why is there references to opinion pieces in the section discussing why chlorophyll has a specific colour? Does this really fit the editorial standards? How are opinion pieces considered scholarly or peer reviewed citations? Alternative one could reference the thermodynamic trade off between chlorophyll synthesis and chlorophyll energy production. After all if one is going to conjecture anything you might as well start by noting that at a minimum the energy extracted chlorophyll has to be used to produce more chlorophyll, which indicates an efficiency feedback, that is it is likely that building a a chlorophyll molecule to extract at all frequencies would require more energy (or entropy) than could be extracted by the molecule. It is probably that their is some peer review literature out there along this line. Ughhh, frustrating Insightaction (talk) 20:38, 2 June 2014 (UTC)

I entirely agree with your removal of the whole section, at least as it was worded. To cause a photochemical reaction, you need to absorb a photon or photons of a particular energy and hence frequency. Ultimately there has to be enough energy to cause H2O → O2 + H+ + e-; absorbing infrared photons for photosynthesis would be pointless. The section seemed to be based on a lack of understanding of the chemistry involved. Peter coxhead (talk) 21:10, 2 June 2014 (UTC)
Or it could simply be that the plant already produces more energy than it can use therefore it doesnt need to absorb all the energy in sunlight. Its more important that it use the nitrogen in the most efficient way possible. Just granpa (talk) 14:42, 16 June 2014 (UTC)

Authenticity of the fluorescent wavelength[edit]

At the end of the article, it is stated that chlorophyll a autofluoresces at 673 nm. Isn't that rather blue? In my experience, the light given off by chlorophyll a under the microscope in response to a fluorescent lamp is apple red. --♦♦♦Vlmastra♦♦♦ (talk) 00:05, 15 April 2008 (UTC)

Checking out the issue, I was apparently thinking of the spectrum backwards... still, is there a cite?--♦♦♦Vlmastra♦♦♦ (talk) 00:39, 15 April 2008 (UTC)
The best I can find is information on the first fluorescence bands to be discovered. It also appears that the wavelength of fluorescnce is temperature-dependent, so I'd be surprised if the 673 nm wasn't tied to a particular temperature. --EncycloPetey (talk) 01:53, 15 April 2008 (UTC)

Do different plants have different type of chlorophyll?[edit]

It is unclear from reading this article whether or not a single plant uses more than one kind of chlorophyll. Is this the case, or is it species-specific? I came to the article to find this out.65.183.135.231 (talk) 17:41, 22 May 2008 (UTC)

The information is addressed in the article about biological pigments. --EncycloPetey (talk) 14:33, 8 November 2011 (UTC)

References[edit]

3. Green, 1984 - Is this an article, book, brochure? There needs to be more information to be able to track this reference down. 130.235.188.110 (talk) 08:28, 21 January 2011 (UTC)~

10. Gross, 1991 - Is this an article, book, brochure? There needs to be more information to be able to track this reference down. —Preceding unsigned comment added by 12.156.213.43 (talk) 17:40, 9 April 2010 (UTC)

Error?[edit]

I have removed the following comment from the article. It seems to be referring to File:Chlorophyll ab spectra2.PNG. -- Ed (Edgar181) 12:05, 8 November 2011 (UTC)

This graph is still incorrect. The Chl b spectrum is not Chlorophyl b - more likely Chl c1c2 (RJ Ritchie 2006)

Chloroplasts and cyanobacteria[edit]

I think the first sentence is incorrect. Do cyanobacteria even have chloroplasts? They are prokaryotes, and I believe chloroplasts are only found in eukaryotes.

bradweir (talk) 21:21, 21 June 2012 (UTC)

Yes, you are quite right. I have edited the sentence. Well-spotted! Peter coxhead (talk) 06:48, 22 June 2012 (UTC)

At what temperature does chlorophyll break down?[edit]

In the video "Do We Really Need the Moon", an astrobiologist is interviewed (from 46:00 onwards) and she says that chlorophyll breaks down at over 70 degrees centigrade. She pointed out that photosynthesis ends when this happens. What is the exact temperature when chlorophyll breaks down, are there any other consequences, does the rate of photosynthesis slow down before the critical temperature is reached? I began to think that plants can cool themselves up to some point, so the air temperature does not probably affect plants quickly. Also, I believe that black asphalt can reach such temperatures and grass and trees can grow near such sources of high temperature air. link to the video on Youtube --Hartz (talk) 13:06, 5 October 2012 (UTC)

About Intelligent Design?[edit]

I will remove the sentence:"Astronomer and mathematician Fred Hoyle conjectured that chlorophyll was likely to be an interstellar molecule, pointing out the similarities of its light absorbing properties to interstellar dust." in the "Why green not black" section. It is not improving the section, and present as true a minor hypothesis, built as a support to intelligent design theory. — Preceding unsigned comment added by 85.81.28.237 (talk) 07:07, 19 March 2013 (UTC)

Agree. Tuvalkin (talk) 16:43, 2 April 2013 (UTC)