DE2620834A1 - PROCESS FOR THE PREPARATION OF 4-HYDROXY L (-) PROLIN - Google Patents

Description

Process for the production of 4-hydroxy L (-) proline

SOCIETE LA BIOCHIMIE APPLIQUEE A L «INDUSTRIE S.A. (SOLABIA)

609848/0982

ORIGINAL INSPECTED

7620834

-z-

The present invention relates to a method for Production of 4-hydroxy L (-) proline, which is more commonly referred to as L-hydroxyproline.

There are numerous processes for the production of L-hydroxyproline, which can be divided into several groups.

In the first manufacturing group there is a synthesis of the compound causes. Due to the two asymmetrical carbon atoms, a mixture of four isomers is obtained: L and D hydroxy-proline, L and D allohydroxyproline, their separation is difficult.

In a second group of processes, L-hydroxyproline is isolated by precipitation from gelatin hydrolysates. Arginine is precipitated first, usually with 2 _f ^ -Dinitro-I-Naphthol-T-sulfonic acid (Flavic acid). Thereafter, the most troublesome aminoacetic acids are precipitated by methyl alcohol, namely lysine and histidine in the form of Phosphortungstaten and / or glycocolla. The hydroxyproline can be precipitated in the form of pure sugar or picrate, the compound obtained later having to be broken down. Precipitation in the form of N-acetyl-O-benzoylhydroxyproline has also been described. These processes are difficult to perform and require expensive products and large amounts of solvents.

A third group of processes makes use of the treatment of a gelatin hydrolyzate with sodium nitrite. All aminoacetic acids are destroyed by the removal of the amines and are therefore no longer recoverable, with the exception of proline and hydroxyproline, which are converted into nitrous acid. This stage poses problems related to environmental safety what also applies to the subsequent phase of reconversion of nitrous acid.

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To the best of our knowledge, no procedure has yet been described which allows the industrial isolation of hydroxyproline by ion exchangers. However, there are methods of deposition of aminoacetic acids known, which should also be applicable for the deposition of hydroxyproline. the main procedures are listed below.

The first method is that you get the protein hydrolyzate passes over exchange columns; it is mostly about carboxyl exchangers with acetates, citrates or other salts can be buffered to pH values on the order of 3 to pH. This makes it possible only at a time one or several aminoacetic acids - depending on the resin content, pH value and ionizing capacity of the buffer - to be retained. However, the ion exchangers behave as a result of the buffering If it is more selective, its performance is considerably reduced, which forces the use of very large quantities is.

A second method consists in fixing all aminoacetic acids on an acid exchanger as well as in one selective washing out by pH buffer with constant or increasing Ionizing capacity, or sometimes by an acid or a base. The exchanger quantities are still here very large, and only dilute solutions are obtained, most of which contain significant amounts of ions which are necessary for the Washout were needed. This principle was mainly used in the analytical field.

Finally, there is the "displacement process" used by J.R. BENDALL, Nature (1947), Volume 16O, page 374, and by S.M. PARTRIDGE, Biochem. Jour. (1952), Volume 51, Page 628, has been described and wherein a hydrolyzate freed from aromatic aminoacetic acids on a strongly acidic exchanger is fixed in hydrogen form, in such a way that half or two thirds of the total capacity can be used. That

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Washing is done with very dilute sodium bicarbonate in order to obtain partially separated aminoacetic acids. Is at This process considerably reduces the exchange volume, so it requires the separation of the aromatic aminoacetic acids very large amounts of active black, and the products obtained are highly diluted. This procedure was also - just like the previous two - never used successfully for the manufacture of hydroxyproline.

It is the aim of the present invention to overcome the aforementioned disadvantages to eliminate by presenting a process for the production of hydroxyproline in which only small amounts of ion exchange can be used without the use of buffers, and which the possible use of low-collagen Products allowed as starting material, which up to now could not be used for the production of hydroxyproline.

The present invention relates to a process for the production of L (-) hydroxyproline, characterized by the hydrolysis of a raw material which contains a possibly pretreated collagen, further by the decolorization of the protein hydrolyzate obtained and by the passage of the solution obtained over a weak basic exchanger, whereby glutamic acids, aspartic acids and mineral anions are retained; After leaving the first exchanger, the solution is passed over a strongly acidic exchanger, the amount of which has been calculated in advance so that 75-95% of the aminoacetic acids present in the solution are retained; the solution is obtained by passing water over the exchanger; then the solution is concentrated to 180-350 g / l hydroxyproline - but preferably between 230 and 280 g / l -, decolorized and, after acidification to 3.8-4.6 pH, crystallized in order to obtain pure hydroxyproline in crystal form.

Another feature of the present invention is insert

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of de-tanned leather waste, of possibly degreased, dehaired and decalcified hides and rinds as well as bone decalcification as raw material.

This raw material can also undergo a pretreatment as described below before hydrolysis in order to facilitate the subsequent stages of the process.

You can of course also use gelatine as a raw material, as this will achieve the best results. However, it is Gelatin expensive. Now, one of the novel features of the method of the invention is that low-collagen (and therefore weakly hydroxyproline-containing) industrial proteins can be used, which are strong mineral or may have other impurities. A previous conversion of the skins or the bone decoction into gelatine is unnecessary. Industrial sub-products made from hides and even cartilage can serve as raw materials.

For example, the following raw materials can be used:

1. Waste from leather processing:

a) Waste from raw hides that may have been dehaired, flesh scraps after soaking or dehairing, split bark, various machine wastes, hides unsuitable for tanning for whatever reason.

b) De-tanned waste (e.g. chrome leather cuttings, waste from vegetable tanning, (after de-tanning).

2. Waste from meat and cured products production:

a) any defatted and / or ground rinds,

b) possibly defatted and pretreated bones,

c) slaughterhouse waste consisting essentially of hides .

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ORIGINAL INSPECTED

These raw materials can be used in their raw state directly for the acid hydrolysis, but primarily the separation the fat is difficult. In fact, filtering for acid hydrolysis is less simple and the lack of uniformity and constancy of the raw material makes production more difficult.

However, this raw material can very well be used in the raw state in the following cases:

- if the waste is in good condition and free of sulfur and calcium and if there is no fat wants to win back. In this case, these raw materials can be used without further ado, and they only need then to be filtered for acid hydrolysis if they are very fatty; in such a case it can it is desirable that they be as described below To undergo pretreatment.

if this waste contains a lot of calcium, but is otherwise in a good state of preservation, because this ion in the manufacturing process described below for hydroxyproline doesn't bother.

- if the environment in which the process for the production of hydroxyproline and other aminoacetic acids takes place, the storage of malodorous raw materials is permitted.

If the quality of the aforementioned raw materials is not sufficient for direct use, the present invention provides pre-treatment of these raw materials; the various corresponding modes of implementation are defined below.

The bones z. B. are boiled or preferably in a pressure cooker with steam injection under a pressure of up to 12 bar but between 1 and 6 bar - treated for 30 minutes to 6 hours. The bone decoction obtained is continuous or in fractions into a fat-like and a

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Separated aqueous phase in which the amino acids are contained in the form of proteins. The separated in this way aqueous phase is then hydrolyzed.

The raw materials can be subjected to an extraction with warm water, the purpose of which is to separate out fats and most of the soluble mineral salts. The product obtained in this way is either in the form of strongly brown-gray colored and non-translucent pieces or in the form of a powder. This product is a good raw material for the production of hydroxyproline and other amino acids, ζ. G. Proline and arginine, according to the process of the invention. It usually contains 5-10 % hydroxyproline and its cost price is much lower than that of the cheapest gelatin.

The raw material can be treated by leaching using protein-degrading enzymes, as described below be: the possibly ground and depending on their content Dry matter enriched with water becomes a Enzyme added, e.g. B. pepsin, trypsin, papain, fradiase (protease of Streptomyces fradiae), pronase (protease of Streptomyces griseus) and subtilisin, or a mixture of enzymes or organs with a high concentration of enzymes such as e.g. B. Pancreas or gastric mucosa, preferably in ground form. The pH is adjusted and depending on the used Maintain enzymes. The degradation can take place at ambient temperature; however, it is better depending on the reaction mixture to heat the enzymes for thermal stability in order to speed up the process and also the separation of the fatty substances to facilitate. The use of anti-bacterial agents is unnecessary if the pH of the reaction mass is very high deviates from neutrality (in the case of pepsin) or if the temperature is above approx. 50 ° C (case with Fradiase and Papain). The separation of the fats is easier if the mass is kept in slow and / or intermittent motion will.

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This stage is especially interesting when the fat content of the raw material is high (which can be the case with rinds, even if they have been previously degreased), namely with regard to the recovery of lard, which in itself makes the process profitable. The protein-containing Decoction is fat-free; it is easy to separate the insoluble constituents low in hydroxyproline therefrom, e.g. B. Hair, nails, foreign bodies of other than protein origin, skin, etc. The protein decoction only has a partial effect Undergo hydrolysis, which are supplemented in the hydrolysis phase of the manufacturing process of this invention got to. However, there are some rare enzymes, such as pronase, that can be used to hydrolyze the acidic process of its manufacture can bypass hydroxyproline according to the invention.

It should be noted that in the special case of de-tanned and sulfur-containing tannery waste, which in the acidic Medium - mainly with pepsin - have been treated, sulphurous hydrogen is released, which can be treated with suitable Must separate or collect means such as ventilation, absorption by sodium bicarbonate, etc.

According to a further embodiment of this invention, the raw materials can be subjected to an acidic pretreatment, which is of particular interest if the storage of waste at the place of manufacture is a nuisance; this is especially true for tanneries. The waste is in as closed a tub as possible with very different Amount of water and a strong acid mixed in. Water is only required when the mechanical aids do not allow waste and acid to be mixed in a sufficiently uniform manner. A strong acid is preferred as the acid Acid like hydrochloric acid, sulfuric acid or phosphoric acid to use, which is needed to keep the pH below 5 and preferably below 3 and stabilize the waste bacteriologically. You can add up to 50 equivalents of acid per kg Dry matter - but preferably up to about 20 equivalents -

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use. If the waste contains sulfur, the released hydrogen sulfide is separated with suitable means or caught. During the subsequent hydrolysis, the amount of acid required can depend on from the amount used for this pretreatment.

The present invention also includes a pretreatment which is a combination of the phases described above represents. It can e.g. B. be of interest to acidify the waste at the place of its generation, then with protein-degrading To treat enzymes, e.g. B. with pepsin, either immediately after the acidification of the waste or as an initial phase in the course of the process for the preparation of hydroxyproline according to the invention. The hydrolysis of the possibly pretreated raw materials can be carried out with any strong acid, e.g. B. with hydrochloric acid or sulfuric acid. Numerous methods are known. All or part of the acid can be used by a known method separate, for example by vacuum concentration (hydrochloric acid) and by precipitating the sulfuric acid with lime. This deposition is not absolutely necessary. However, the acid concentration must be increased either by separation or by dilution to a value below 4N, preferably below 2.5N.

According to the invention, first of all a decolorization with the aid of an activated carbon or preferably by contact with a decolorizing agent Resin causes. For this, z. B. a Duolit S 30 resin or Duolit ES 861 from DIA-PROSIM, 107, rue Edith Cavell, 94 Vitry. The decolorization does not necessarily have to be done in this phase, but it does Advantage of protecting the remaining, subsequent resins and improving the effectiveness of the cleaning processes brought about by these resins. It is also possible to have this decolorization phase during another stage of the procedure, or

6098 4 8/0982

ORIGINAL INSPECTED

2620334 - ίο -

but to carry out one or more additional decolorization.

The hydrolyzate is passed over an anion exchanger with weak polarity, i. H. weakly basic, which is previously in OH form was brought. This exchanger holds the acid used for the hydrolysis or what is after the deposition is left of it, completely back. It also holds at least two thirds of glutamic and aspartic acids - but preferably 9/10 - back.

The weakly basic exchanger can, for. B. a Duolit A 366 resin from DIA-PROSIM or an Amberlit IR 45 from the company ROHM & HAAS. It is advantageous to distribute it over two columns connected in series.

The main advantage of a weak polarity of the anion exchanger is that the regeneration is less expensive than with high polarity, but the effectiveness of the treatment is reduced perfectly sufficient.

The solution is then passed through a cation exchanger, which must have a strong polarity. However, it is it is possible to make its regeneration more economical by replacing it with a weakly acidic one immediately preceding it Exchanger protects. The last-named exchanger fixes the cations, which are then the most difficult to displace, when they are fixed on a strong exchanger. An Amberlite IRC 50 resin from ROHM & HAAS or Use Duolit C 464 from DIA-PROSIM. The regeneration medium is reversed during the regeneration phase Direction directed over the solution to be treated, d. H. starting at the strong exchanger.

The cation exchanger with strong polarity (strongly acidic) is able to use all Withhold aminoacetic acids. It is important here to limit the amount of exchanger so that it is saturated,

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ORIGINAL INSPECTED

before he has fixed all of the ingested aminoacetic acids. The correct amount depends on the performance of the exchanger, which is often very different, and also on the cation content of the hydrolyzate and on the presence of the aforementioned protective exchanger. The amount must be calculated in such a way that 75 - 95 % of the aminoacetic acids absorbed are fixed. 75-85% should preferably be retained in the case of a raw material containing very high levels of hydroxyproline, such as a gelatin hydrolyzate, or 85-95 % in the case of a raw material low in hydroxyproline.

A Duolit C 25 D resin from DIA PROSIM or an Amberlit IR 120 resin from ROHM & HAAS can be used.

The capacity of these resins is 2 equivalents per liter. It takes 2.5-6 liters to treat 1000 g of aminoacetic acids. Too large an amount of strongly acidic resin will cause the hydroxyproline yield is low or zero; too little resin, on the other hand, leads to insufficient enrichment, so that crystallization of the recovered product does not give a sufficiently pure product.

It is too difficult to achieve a good yield and a high degree of purity at the same time when the resin is only contained in a single column. Two columns of the same type produce good results, although it is better if the first column has a higher capacity than the second column.

The cation exchanger is used in H ⁺ -FOiTn. No washout buffer or reagent is used that would require further separation. The amount of aminoacetic acids fed to the cation exchanger must be regulated very precisely. A change in the moisture content in the raw material or a loss of solution during a preceding phase can namely lead to the disadvantage already mentioned

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an excess or lack of resin. For elimination this disadvantage makes it possible to control, for example, the amount of aminoacetic acids supplied. In case of excess the excess amount can be deposited or, in the case of a deficiency, amino nitrogen can be maintained at a constant level by adding to be supplemented by ammonia.

The regeneration of the exchangers does not present any particular difficulties. In general, this is done with baking soda or Ammonia with 1 to 4 N is used for the basic exchanger, hydrochloric acid or sulfuric acid of 1.5 - 4 N with possibly a preceding one Leaching by ammonia for the acid exchanger (s) and finally soda or ammonia from 0.3 to 3 N with possibly subsequent 0.2-2 mol / l hydrochloric acid for the adsorbent resin.

The solution, which is obtained after passing through strongly acidic resin, has a straw yellow color, a pH value between 3 »8 and 5 - preferably 3.9-4.5 - and contains, especially depending on the dilution of the hydrolyzate, 5 40 g / l hydroxyproline, but preferably 20-35 g / l.

If the previous steps have been carried out correctly and, above all, has the amount of aminoacetic acid been correctly calculated, which is to be treated per liter of exchanger, the leaching product contains 30 - 60 g of hydroxyproline per 100 g of aminoacetic acids, but preferably 35-50 g.

Before the crystallization phase, concentration and, in general, decolorization are necessary, the sequence of these two operations being irrelevant. It is possible to do a pre-concentration followed by decolorization and final concentration. It is concentrated until a pale yellow colored solution is reached, which contains approximately 180-350 g / l hydroxyproline, but preferably 230-270 g / l _; contains.

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If necessary, the concentrate is acidified with a small amount of acetic acid or formic acid to the point that one pH of 3.8-4.6, but preferably between 4 and 4.3, is maintained. This acidification is not always necessary.

The crystallization is brought about by adding an alcohol such as ethyl or methyl alcohol. You can also use a mixture use in particular from the two aforementioned alcohols. One volume unit of concentrate becomes 1-4 volume units Alcohol, but preferably 2-3 volume units, is used.

The suspension of crystals is preferred after 12-48 hours of residence in a cold room - between 0 and - filtered. The crystals are mixed with a volatile solvent that mixes with water - such as one of the aforementioned Alcohols or their mixture - purified. After that, they are either in a vacuum or in a ventilated heating cabinet spun between 40 and 110 ° C and dried.

The drying does not need to be very thorough, as in general recrystallization is required. It is carried out exactly like the first crystallization, namely after dissolving the crystals in water to a concentration of 180-400 g / l hydroxyproline, but preferably between 250 - 350 g / l. Decolorization, such as with activated charcoal, is generally useful prior to adding the alcohol.

In addition to the recovery of hydroxyproline, this process also allows the recovery of interesting sub-products both from the crystallization mother liquor and from the leachate of the exchangers. A mineral salt free and low-glutamic acid, aspartic acid and low-hydroxyproline collagen hydrolyzate is made by washing out the strongly acidic exchanger with ammonia in 0.5 N - 3 N and by vacuum concentration of the Leach product obtained. It can be used as a fraction or as it is. ,

609848/0982

ORIGINAL INSPECTED

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The following examples are given to illustrate the present invention.

EXAMPLE 1

250 liters of water, 250 kg of technical sulfuric acid and 250 kg of hide glue are placed in an autoclave equipped with a stirrer. The mixture is heated to such an extent that a pressure of 1 bar is maintained inside the autoclave for eight hours. At the the following day 550 liters of black liquid are drawn off, which are diluted to 1,800 liters and 20 kg of diatomite are added will. Then it is filtered.

The filtrate is then passed over 4 columns mounted in a row, which in the correct order 500 liters of Duolit S 30, 1100 liters of Duolit A 366, another 1100 liters of Duolit A 366 and 820 liters of Amberlit IR 120. As soon as all of the filtrate has been given up, water is driven in until it is drained of amino acids. About 1000 liters of solution are obtained which contain 85 kg of dry matter, 23 kg of which are hydroxyproline. The solution is then passed through a column containing 270 liters of Amberlit IR 120 and forced through with water. You get 570 liters with a hydroxyproline content of η 12.5 kg and 28 kg dry matter.

This solution is vacuum-concentrated to a volume of 45 liters, then decolorized at 80 ° C. with 500 g of Acticarbone 2S and filtered. After washing the black cake, 48 liters of solution are obtained.

It crystallizes by adding 120 liters of methanol; this is followed by a few hours of settling and lingering in one cool room for the day after next.

Filter in vacuo, wash the crystals with about 20 liters of methanol, spin thoroughly and dry. This equates to 8.8 kg

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ORIGINAL IMSPECTED

Product which contains 5-10 % proline, 3-5 % glycine and 0.5-1% alanine. The product is dissolved in 22 liters of water; 350 g of Acticarbone and 30 ml of formic acid are added to bring the pH to 4.2. Then it is heated to 70 ° and filtered. After washing the black product, 30 liters of solution are obtained, which is crystallized by adding 75 liters of methanol. The crystals are cleaned with methanol and dried. 6.5 kg of hydroxyproline are obtained.

EXAMPLE 2

The procedure is the same as in Example 1, but the column with 270 liters of Amberlit IR 120 is omitted. The solutions are divided in 3 successive steps and then together over the 820 liter column directed.

EXAMPLE 3

The procedure is as in Example 1, but the solution is passed directly from the first to the second column with IR 120 without prior collection or dosing.

EXAMPLE 4

The procedure is as in Example 1; after collecting the aminoacetic acids not fixed on the columns with IR 120 resin However, the aminoacetic acids fixed by ammonia 2 N will be washed out: 1200 liters for the first column and 400 liters for the second. The leachates are collected by fractions and then the ratio of Hydroxyproline / total aminoacetic acid concentrations determined.

The most productive fractions can be crystallized provided that their mixture contains more than 38-40 % hydroxyproline.

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The remaining fractions are either returned to the column with 270 liters of Amberlit IR 120 (more than 20 % hydroxyproline content) or mixed with a hydrolysis stock (content 10 - 20 %) or for the production of by-products (content below 10 %) with the next batch. ) is used.

With this process a yield improved by about 20% is achieved.

EXAMPLE 5

Identical to any of the preceding examples, but with the crystallization mother liquors after distillation of the alcohol can be reused. The mother liquors from the first crystallization are used in the subsequent hydrolysis decoction added. The mother liquors from the recrystallization become the solution to be crystallized in the subsequent operation added.

EXAMPLE 6

2 Identical to any of Examples 1 to 5, the

-1

However, crystallization mother liquors are passed over an IR 120 resin, in a ratio of 150 g of aminoacetic acids per liter of resin. When you exit the column you get a from Aminoacetic acid-free water-alcohol mixture that can be easily distilled. The aminoacetic acids become ammonia Washed out 2 N and the fractions obtained are then used as in Example 4, depending on their degree of purity.

EXAMPLE 7

The hydrolysis is carried out as in Example 1. 290 liters are taken from the 550 liters of hydrolysis effluent and neutralized them with milk of lime to get a pH of 7.3.

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The calcium sulfate cake is filtered and washed with water. The filtrate and wash water are with the rest of the non-neutralized hydrolysis effluent. This gives 750 liters, which contain 1400 acid equivalents.

The following day 20 kg of diatomite are added; the liquid is filtered and passed one after the other over 300 liters of Duolit S 30 resin, 1000 liters of Duolit A 366, which is distributed on two columns of 500 liters each, like over 1350 liters of amberlite IR 120 resin in two columns (900 + 450 liters).

400 liters are obtained, which contain 9.5 kg of hydroxyproline, which crystallize and recrystallize them as in the above Examples and gains 4.5 kg of hydroxyproline

The 450 liter column is washed out by 60 liters of 2 N ammonia (minor washout) to give 380 liters of washout product to obtain, which contains 6 kg of hydroxyproline and 19 kg of other aminoacetic acids. This washout product is passed through a column with 200 liters of IR 120 after the crystallization mother liquors. By washing out with 100 Liters of ammonia 2 N give 110 liters of solution, which is 6 kg Hydroxyproline contains 9 kg of other aminoacetic acids. There are 3 crystallizations to obtain 2.3 kg of hydroxyproline necessary.

EXAMPLE 8

Identical to example 1; the column with adsorbent resin S 30 is here, however, arranged between the pillars with A 366.

EXAMPLE 9

Identical to example 1; the column with Amberlit IR 120 contains only 600 liters of resin instead of 820 liters.

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ORIGINAL INSPECTED

In addition, this column is a column with 200 liters of Duolit C 464 connected upstream.

EXAMPLE 10

100 kg of non-ground rind, 1 kg of powdered papain and 2 liters of acetic acid are placed in a solution with 25 liters of water in a 500-liter tub. It is heated to 60 ° C. The rinds gradually sink in, while the liquid level rises as the seeds continue to be sown. After one to two hours, the reaction mass can be easily stirred; stirring is continued at regular intervals. The next day, the lard floating on top (14 kg) and 90 liters of aqueous solution with 30 % dry extract and small, suspended solids are drawn off.

27 kg of sulfuric acid are added to this solution; the reaction mixture is in an autoclave (identical to the one in Example 1) heated. In this way 100 liters of a black brew are obtained, which is diluted to 200 liters.

This solution is then treated as described in Example 1, the amounts of resin and reactants used being im Ratio 1: 9 can be reduced.

EXAMPLE 11

200 kg of various tannery waste, 100 liters of warm water and 200 g of sulfuric acid are added; the mixture is stirred slowly, 100 g of pepsin and a sufficient amount are added Add amount of sulfuric acid to bring the pH to 1-1.5. The temperature will be between 35 and 40 ° C and kept the pH between 1 and 1.8. To The stirring is stopped after about 24 hours of treatment. You can decant and collect separately:

- 25 kg agglomerated and coagulated on the surface

Fat that is separated and

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. ORIGINAL INSPECTED

230 liter solution, which contains 21 % dry extract as well as various insoluble components and from which hydroxyproline can be produced according to the method described above.

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ORIGINAL INSPECTED

Claims (19)

2B20834 PATENT CLAIMS \ 1.,. Process for the production of 4-hydroxy L-proline, characterized in that a raw material with possibly pretreated collagen contained therein is hydrolyzed, then the protein hydrolyzate obtained is decolorized and the solution is passed to a weakly basic exchanger to remove the glutamic acids, aspartic acids and retain mineral anions. The solution emerging from the first exchanger is then passed to a strongly acidic exchanger which is provided in a pre-calculated amount so that it retains 75-95% of the aminoacetic acids present in the solution. The solution is collected by passing water over the exchanger. The solution is then concentrated to 180-350 g / l hydroxyproline, but preferably to 230-280 g / l, decolorized and, after acidification, crystallized to 3.8-4.6 pH to obtain the pure hydroxyproline in crystal form. 2. A method for the preparation of hydroxyproline according to claim 1, characterized in that the raw material is made from de-tanned leather waste, from possibly defatted, dehaired and decalcified skins and rinds as well as bone decal. 3. The method according to claim 2, characterized in that the untanned and possibly decalcified waste by extraction be degreased with warm water. 4. The method according to claim 2, characterized in that the tanned waste cold or at a temperature of below 100 ° C can be de-tanned. 5. The method according to claim 2, characterized in that the untanned waste a pretreatment with one or several protein-degrading enzymes or with protein-degrading - 21 609848/0982 ORSGiHAL INSPECTED > -; 2 O: ί 3 4 organs rich in building enzymes are subjected and the separated fat is possibly collected, 6. The method according to claim 5, characterized in that the protein-degrading enzymes are pepsin, trypsin, papain, Fradiase (protease from Streptomyces Fradiae), pronase (protease from Streptomyces Griseus) and subtilisin. 7. The method according to claim 2, characterized in that the untanned waste is pretreated with strong acid be subjected. 8. The method according to claim 7, characterized in that it is hydrochloric acid, sulfuric acid or the strong acid Phosphoric acid, 9. The method according to claim 2, characterized in that the Bone aDSUd by long boiling in water or by steam injection into an autoclave and by subsequent Deposition of an aqueous phase obtained therefrom is obtained with the aid of decantation. 10. Manufacturing method according to claim 1, characterized in that that the hydrolyzate is decolorized over a decolorizing resin or activated charcoal. 11. Manufacturing method according to claim 10, characterized in that that the decolorizing resin is a Duolit S 30 or ES 861 resin. 12. Manufacturing method according to claim 1, characterized in that that the weakly basic exchanger is a Duolit A 366 or Amberlit IR 45 resin. 13. Manufacturing method according to claim 1, characterized in that that the strongly acidic exchanger is a Duolit C 25 D or Amberlit IR 120 resin, which in a - 22 - HO 9848/0982 ORIGINAL INSPECTED Amount of 2.5-6 liters per kg of aminoacetic acids used will. 14. Manufacturing method according to claim 1, characterized in that that a weakly acidic exchanger is placed in front of the strongly acidic exchanger. 15. Manufacturing process according to claim 14, characterized in that that the weakly acidic resin is Amberlit IR C 50 or Duolit C 464 resin. 16. The method according to claim 1, characterized in that the Discoloration phase or phases can be carried out at each stage before the final crystallization can. 17. Manufacturing method according to claim 1, characterized in that that by adding one to four volume units of alcohol, but preferably from two to three Units of volume, per unit volume of the solution is crystallized » 18. The method according to claim 17 »characterized in that the alcohol is methyl or ethyl alcohol or a mixture thereof. 19. The method according to claim 1, characterized in that the aminoacetic acids, except for hydroxyproline, which on the acid exchangers are fixed, can be obtained by washing with ammonia. 60 984 8/09 8 2 'OR ₁ GiNAUNSPECTED