Sciencemadness Discussion Board

Cholesterol

chromium - 25-7-2006 at 13:51

In my opinion cholesterol is funny substance because many of its esters have liquid crystal properties. For example:

Quote:

Cholesteryl benzoate - Cholesterol is boiled with benzoyl chloride for a few minutes and the solution poured into alcohol. The precipitate of cholesteryl benzoate is recrystallised from hot alcohol. This compound melts at 145C to a turbid liquid, which becomes clear at 178 - 180C; on cooling, it exhibits a play of colours, of which blue is the most marked.


I know two ways how to obtain cholesterol, neither of them is quite what i want (or can) to do:

Quote:

Preparation.
(1) From Gallstones.
Cholesterol is most easily prepared from gallstones. The powdered stone is extracted with mixture of ether and alcohol. The filtered solution, on evaporation, leaves a residue of cholesterol. It is purified by boiling with alcoholic potash, the solution is evaporated to dryness and residue extracted with ether. The crystals obtained after evaporation of the ether are recrystallised from alcohol.

(2) From Brain.
Sheep's brain is dried, or ground up with some sand and about 3 parts of plaster of Paris. The dry material is powdered and covered with acetone. The acetone is filtered off and the mass again treated with acetone. On distilling off the acetone, crystals of cholesterol remain. They may be purified as above.


Any other ways how to buy, extract or make it?


(Quotes are from: R. H. A. Plimmer - Practical organic and bio-chemistry, 1926, pages 343 - 344)

not_important - 25-7-2006 at 14:55

If you don't want to pay the prices to get cholesterol, its esters, or other liquid crystal materials, from vendors, the you are pretty much forced to extract it from animal products.

If zombie food (brains) or gallstones of any sort aren't your idea of fun, you get forced into less rich sources sources. Eggs or butter, kidneys, liver, or maybe the Asian shrimp paste could be used. None of these is as good as (begin zombie font) brains (end zombie font). As shown in the following link, brains have at least three times as much cholesterol as other meats, and about 5 times as much as eggs (gram for gram). A Kg of butter nets you about 2 grams of cholesterol, about 1/10th what brains yield.

http://www.ruchihealth.com/health/cholesterol_content.htm

With meat you'd have to grind it first; eggs, liver, or shrimp paste would be boiled with toluene using azeotropic distallation to first remove the water. After that cool and filter, then wash the residue with more toluene. Combine the extracts and distill off the toluene, leaving the fatty material.

For butter or the above fatty extract follow the gallstone process of alcoholic saponification, drying, and extraction.

chromium - 25-7-2006 at 15:08

I have nothing against the brains or gallstones. I just have no idea where to get them without killing animals myself.

not_important - 25-7-2006 at 15:38

Ummm ...

http://www.alibaba.com/catalog/10283135/Ox_Cow_Cattle_Gallst...

fresh brains should be available at butchers, perhaps 'ethnic' depending on where you live. Ditto for kidneys, liver is a more common meat organ. Brains may be cheap now because of worries about BSE. If you can find a slaughterhouse ask there.

Sandmeyer - 25-7-2006 at 16:10

Duh, even my grandmother knows where cholesterol is present, but how is he supposed to isolate that compound from materials you mention? Do you have a method or what? Why not simply buy it from a chem supplier?

EDIT: sorry I somehow managed to miss the method you provided... ;) But is there a reference?

[Edited on 26-7-2006 by Sandmeyer]

Vitus_Verdegast - 25-7-2006 at 17:13

the Merck Index sez:

Prepared commercially from the spinal cord of cattle by petroleum ether extraction of the non-saponifiable matter. Also produced from wool grease. Cholesterol from animal organs always contains cholestanol (dihydrocholesterol) and other saturated sterols.

Laboratory procedure for isolation from gallstones:
L.F. Fieser, Organic Experiments (Heath, Boston, 3rd ed. 1964 p.70)

Practically insoluble in water (about 0.2mg/100ml)

Slightly soluble in alcohol (1.29% w/w at 2O°C), more in hot alcohol (28g in 100g 96% EtOH at 80°C)

One gram dissolves in 2.8 ml ether, 4.5 ml chloroform and in 1.5 ml pyridine

Also soluble in benzene, pet ether, oils, fats and aqueous solutions of bile salts. This should provide enough data to perform a crude extraction.

sparkgap - 25-7-2006 at 18:07

We extract cholesterol from egg yolks back here. ;) The slaughterhouse's so far away...

Extract with ethanol, vaporize, reflux with ethanolic KOH, neutralize, salt out, recrystallize, and voila. :D

sparky (~_~)

Vitus_Verdegast - 25-7-2006 at 18:44

Around here brains are sold cheaply as a food item in every supermarket. I suppose the Bovine Spongiform Encephalopathy Security Code has turned green over the years :P

What about drying them in an oven, grounding, and a continuous extraction with ether before proceeding to the saponification stage? :cool:

EDIT:

Or this might be preferable:

"Lanolin is chiefly a mixture of cholesterol and the esters of several fatty acids. Crude (non-medical) grades of lanolin also contain wool alcohols, which are an allergen for some people. It is insoluble in water, but forms an emulsion."

"Lanolin is often used as a raw material for producing vitamin D3."

"Lanolin is used commercially in a great many products ranging from rust-preventative coatings to cosmetics to lubricants."

The Ghost of Emanuel Merck whispers:

Chemically it is a wax rather than a fat, being a complex mixture of esters and polyesters of 33 high molecular weight alcohols and 36 fatty acids. The alcohols are of three types: aliphatic alcohols, steroid alcohols and triterpenoid alcohols.

Reviews on composition, derivatives, modifications and uses:
Drug & Cosmet. Ind. 80, 744 (1957) and 83, 292 (1958)
Chemiker Ztg. 83, 707 (1959)

Monograph:
Wool wax, Chemistry and Technology (Interscience 1956)

Lanolin contains about 25-30% water. It is a white unctuous mass; shlight odor. Practically insoluble in water, soluble in chloroform or ether with separation of the water.

Anhydrous lanolin is sparingly soluble in cold, more so in hot ethanol.

Freely soluble in C6H6, Et2O, CHCl3, acetone, pet ether and CS2.



[Edited on 26-7-2006 by Vitus_Verdegast]

not_important - 25-7-2006 at 19:08

Drying should work, but it's slower than some like. A food dehydrater is another option, perhaps.

Doing the extraction with alcohol or acetone can get away from the drying, it that you will pull much of the water out of whatever. If you then treat the extract with solid salt, much of the water will go into forming a brine. Separate, distill off the solvent; this should denature proteins and the like that have tagged along. After than the saponification; alcoholic KOH is good but more expensive, I've just done aq NaOH in an asparagus steamer pot - scientific term "a tall stainless steel beaker" - under ultrasound - a used, hacked jewelry cleaner. Added a little alcohol and extract with "pet ether" - distilled petrol or naphtha, fractionated to get ride of the higher boiling crude.

No refs, acquired over years of reading older chemistry and biology books.



Vittus - I don't see an inhabitant of Bedlam as being worried about BSE 8-)

Edit - ver good, I forgot about lanolin. Fairly cheap

http://www.libertynatural.com/bulk/94.htm



[Edited on 26-7-2006 by not_important]

Vitus_Verdegast - 25-7-2006 at 21:43

Can you give an estimate of the yield of cholesterol you obtained?

I wonder how much is to be obtained from lanolin too...

Quote:

Vittus - I don't see an inhabitant of Bedlam as being worried about BSE 8-)


:D :D
I have business interests with the National Cattlemen's Beef Association and the USDA

chromium - 26-7-2006 at 01:05

Many thanks for all! I think, egg yolks may be best way for first tryout.

Sparky, do you dry egg yolks somehow before extracting them with ethanol? How much ethanol do you use for given amount of egg yolk?

sparkgap - 29-7-2006 at 06:39

Nah, drying wan't done, chromium. We just plunked the finely mashed yolks into hot alcohol. It was 6 yolks to 120 mL of alcohol. We netted around half a gram of cholesterol for those 6 yolks. Of course, this can vary depending on how healthy were the chickens that laid those eggs. ;)

(edit: IIRC, there are eggs that have more cholesterol in the yolk than chicken's. You might want to experiment a bit if other bird eggs are accessible in your area)

sparky (~_~)

[Edited on 29-7-2006 by sparkgap]

Vitus_Verdegast - 29-7-2006 at 09:44

The British Pharmaceutical Codex.
Published by direction of the Council of the Pharmaceutical Society of Great Britain, 1911.


ADEPS LANAE B.P.
WOOL FAT.

Wool fat, or anhydrous lanolin, is a purified cholesterol fat obtained from the wool of the sheep, Ovis aries, Linn. (Order Ungulata). The natural grease is extracted from the wool by kneading with water, with which it readily forms an emulsion; on heating, it separates as a distinct layer at the surface of the liquid. Purification is effected by repeated treatment with water in a centrifugal machine, or by some other suitable process. Wool fat is also official in the U.S.P. It occurs as a light yellow, tenacious, fatty mass, having a slight, peculiar odour, and not readily becoming rancid. Melting-point, 40° to 44.4°.

If 1 gramme of wool fat be boiled with 20 mils of alcohol and the solution filtered after cooling, the filtrate should not be rendered turbid by the addition of a 5 per cent. alcoholic solution of silver nitrate (absence of chlorides). A distinctive test for wool fat is that for cholesterol—1 gramme of the fat dissolved in 3 or 4 mils of acetic anhydride gives with 3 decimils (0.3 milliliter) of sulphuric acid a pink colouration, soon changing to green and blue. When a 2 per cent. solution in chloroform is gently poured over the surface of concentrated sulphuric acid it gradually develops a purple-red colouration at the junction of the liquids. If 10 grammes be heated with 50 mils of water on a water-bath the aqueous layer on filtration should not yield glycerin on evaporation, and when boiled with potassium hydroxide should not evolve the odour of ammonia (absence of nitrogenous organic matter).

The saponification value of wool fat ranges from 90 to 102. It is practically impossible to saponify wool fat in aqueous solution of potassium hydroxide, but saponification may be effected by alcoholic potash under pressure; on evaporating the alcohol from the saponified liquid and dissolving the residue in water the cholesterol may be extracted by means of ether; on evaporating the ethereal liquid the cholesterol is left in the form of characteristic scaly crystals. Soft paraffin, being unsaponifiable, would be readily detected by the saponification test, and so also would glycerides by their much higher figures.

Insoluble in water; sparingly soluble in alcohol, more so in boiling alcohol (about 1 in 75), the hot alcoholic solution, on cooling, depositing most of the wool fat in the form of flocks; readily soluble in chloroform, ether, carbon bisulphide, acetone, benzene, or petroleum ether.

Constituents.—Wool fat contains the alcohols cholesterol and isocholesterol, together with various esters, the acids in combination being lanoceric, lanopalmitic, carnaubic, myristic, oleic, and probably cerotic and palmitic acids.

Uses.—Wool fat is closely allied to the natural secretions of the skin; recent experiments show that, in the pure state, it is not very readily absorbed, but when mixed with an equal quantity of olive oil or soft paraffin it readily penetrates the skin, and is useful for promoting the cutaneous absorption of drugs. Unlike lard it does not become rancid. It takes up about 50 per cent. of water, and is thus available for use in ointments in which the proportion of water is too great to permit of incorporation with any other fatty base. By the addition of a small quantity of wool fat to soft or liquid paraffin, the latter can be formed into stable emulsions with water, as in the preparation of parenols.
PREPARATIONS.

Adeps Lanae Hydrosus, B.P. and U.S.P.—HYDROUS WOOL FAT.
Wool fat, 70; distilled water, 30. Hydrous wool fat is employed as an ointment basis, generally for substances in aqueous solution. It may be mixed with olive oil, soft paraffin, or lard, by which its stickiness is much diminished and its absorbability increased.

Unguentum Adipis Lanae, Ph.G.—WOOL FAT OINTMENT, Ph.G.
Wool fat, 20; distilled water, 5; olive oil, by weight, 5.

Unguentum Lanolini, B.P.C.—LANOLIN OINTMENT.
Hydrous wool fat, 50; soft paraffin, 50. Mixes well with powders, oils, and aqueous solutions, and is a useful basis for dispensing purposes.

Unguentum Lanolini Anhydrosi, B.P.C.—ANHYDROUS LANOLIN OINTMENT.
Wool fat, 50; soft paraffin, 50.

Unguentum Lanolini Oleosum, B.P.C.—OILY LANOLIN OINTMENT. Syn.—Wool Fat Ointment.
Hydrous wool fat, 9; olive oil, 1. Used as an emollient, and as a basis for the application of drugs that are required to penetrate the skin.

gil - 16-12-2006 at 18:43

Chicken egg contain about 0.200 g. of colesterol,almost all in the yolk.goose and duck may have 25% more,for the same weight. Animals diet will greatly influence this figures.

[Edited on 18-12-2006 by gil]