How to extract Flavonoids?

Question

I need some help with a chemistry project, im looking for a flavonoid extraction and i dont find any exact one.

I need the exact sustances to it, the process, and i heard something about i can extract it from the orange or any other fruit.

Thanks. Sorry but my english is not so good

Answer 1

Flavonoids in plants typically consist of flavonoid glycones... the flavonoid "nucleus" with a sugar "tail".  The glycones are fairly soluble in polar solvents, including water -- but alcohol is more typically used.

Flavonoid aglycones (with the sugar removed) are soluble in non-polar solvents.

You can make a first pass at the problem with chucking some plant tissue in a blender or tissue macerator with a fairly minimal volume of 95% EtOH (a sparkproof blender is nice, otherwise things can get exciting!).  Blend well, then vacuum filter and wash with more EtOH, and concentrate the material in a vacuum dryer.   You can further extract any aglycones by re-macerating the tissue with ethyl acetate and refiltering and then drying down the extract under vacuum.  In orange, you're going to get a bunch of carotenoids, too.

If you're just interested in the aglycones, macerate the tissue in weak HCl (I've forgotten the concentration we used) in a hot water bath.  Extract with ethyl acetate.

You can finetune these procedures for various species and various chemical species you wish to extract, but for quick survey work, these do pretty well.  Supercritical fluids are used  some now, but that's a bit more specific than I think you want.

You'll want to check on the work Jeffrey Harborne and Tom Mabry did in the late 60's and onward.  There are several books like "The Flavonoids" with information that I think you may want to review.

Answer 2

first the main factors of the extraction temperature, the concentration of the extracting agent, extraction time and the materials ratio (the weight of fruits: volume of the extracting agent), which affect the extraction of flavonoids were studied individually, and then the optimum extracting conditions of flavonoids from raspberry fruits were determined by adopting L9(33) orthogonal experiments after making  analysis of variance and significance evaluation diagram of extracting process was: materialsextract filter enrichment  extracted by using ethyl acetateraw extract of flavonoidsconfirm the volume by using 95% ethanol solution measure.