[Corvettaholic]

I did some reading on chlorophyll and all the other pigments and molecules that go with it, and I have a couple questions. I do understand that it takes light energy to knock electrons around to convert the input CO₂ and H₂0 to create what looks like a hydrocarbon and O₂. What I want to know is by just having a ton of chlorophyll in a pool of water, can photosynthesis occur outside of a plant? I mean it can't really be this simple, because I have a tendency to oversimplify things, but what would I REALLY need to perform photosynthesis outside of a plant? Like in a dish?

The reason for doing this is I want to harvest the hydrocarbon, burn it, and spin a small steam generator. Pretty much want my garden to power my low power outside lights. I got interested in this after my solar cell discussion on a high voltage forum, where solar cells are 30% efficient, and plants are something like 80%.

[ATMyller]

I never heard of in vitro photosynthesis done in practice. It would be cool if someone could pull that off: goodbye need for raw oil, goodbye global warming.

[jdurg]

I've actually never heard of photosynthesis resulting in the creation of a burnable hydrocarbon.  I have always been taught that it produces a carbohydrate.  (Hence why plants do it.  To create the carbohydrates they need for energy).  Plus, if you look at the formulas of the products and reactants, into the photosynthesis goes CO₂ and H₂O, and out of it definitely comes O₂.  Therefore, the only thing left is a carbon atom and a water molecule which would together form a carbohydrate.  (As I don't think they would just form CH₂O which is also known as formaldehyde).  

[dexangeles]

6H2O + 6CO2 ---photosynthesis-----> C6H12O6 + 6O2  

[Corvettaholic]

A carbohydrate, right. Can't you burn those? Its got the carbon, its got the hydrogen, but will the oxygen screw it up?

[dexangeles]

I believe, as far as I remember, dehydration of glucose + fructose produces sucrose (table sugar), a disaccharide we get from beats, sugar cane, etc....

well you can burn sugar, but I don't know if it will serve your purpose  

i'd rather burn it a lil and have it kinda soft like caramel  

[jdurg]

Carbohydrates can burn, but they aren't volatile so you have to heat up the solid mass quite a bit so that it can melt and then burn.  Basically, it's like trying to burn sugar for fuel.

[Kong]

Pouring Chlorophyll pigment in a pool and expecting energy to come of it is sort of like drinking lighter fluid and expecting.....I don't know to be able to run faster or something.  

For the most part the chloroplast(engine) does the work.  The chlorophyll just obsorbs the energy. (gasoline)

[Kong]

I used to have a pool  as well.....If you let it sit for a long time it actually fills with quite alot of chlorophyll all by its self.  


The collection of light by the chlorophyll causes an oxidation reduction reaction that as I understand it creates electrons.  These electrons inside the chloroplast creates a voltage.  As the electrons flow through channesl to equlize the voltage reactions are driven.  In a nut shell.  

[Corvettaholic]

Kong, you mentioned the magic word, "voltage"! I found something similar to your explanation on google, but there wasn't enough info for me to fab up an experiment. I have an inflatable kiddie pool just DYING to produce electricity. So the chloroplast is the motor, and the chlorophyll supplies a usable fuel. How in the world would I be able to isolate chloroplasts?

[savoy7]

To add to Kong's explanation

In organisms energy production - that is not biochemical but chemiosmotic - requires a double membrane to produce a conc gradient with H+ or protons.  We see these double membranes in Mitochondria (eukaryotes use this organelle for oxidative respiration), Chloroplasts (the organelle this forum has been talking about) and even in some prokaryotes (bacteria)

in just scratching the surface- In green plants
photons hit the pigment - chlorophyll is one example (different types depending on species) - the pigment becomes "excited" of course this requires the light to be a specific wavelength - chlorophyll absorbs in the extremes of the visible light spectrum of the EMS & reflects in the middle - hence green plants

The pigment when excited "transfers" electrons to a series of proteins in one of membranes of the chloroplast - these series are called Photosystems (I & II)  & there are several results of this process:  one you've mentioned in the photosynthesis equation - water will breakdown into Oxygen gas and Hydrogens

the other is the part that "powers"
H+ are pumped against the gradient into the interior of the thylakoid - there is a high conc of them there and they want to get out - so they passively go through an ATPase to produce ATP

anyway - long story short - products of these photosystems (ATP & electron carriers like NADPH) are used in either a C3 or C4 cycle (Calvin) to produce glucose


I really shorten this - a good resource for cellular biology is Molecular Biology of the Cell by Alberts et al


As far as isolating chloroplasts - not to hard - usually done in an undergraduate cell biology course.  Any cell biology lab manual will probably have students blending some spinach to isolate chloroplasts.  An old manual would be Gasque (~1989).  There's a lab in there for isolating chloroplasts.  He's an old prof of mine.  Went to his website and he had a link to an online cell biology lab manual from Gustavus Adolphus College http://homepages.gac.edu/~cellab/chpts/chpt8/ex8-1.html   I gave it a glance, looks similiar to what I did a long time ago.  Also explains how to remove outer membrane of the chloroplast.


The concept of active transport (proton pump) to produce a conc gradient which then can use passive transport (facilitated diffusion through an ATPase or other proteins) is a commonly used process to convert energy in the biotic world.

[Corvettaholic]

I understand a lot more now, thanks! So it appears there won't be any clear anode or cathode, so too bad for voltage production. Oh well, it was worth a thought!

[dexangeles]

a potato works