KR101023538B1 - A method of producing L-Cystine - Google Patents
A method of producing L-Cystine Download PDFInfo
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- KR101023538B1 KR101023538B1 KR1020090005408A KR20090005408A KR101023538B1 KR 101023538 B1 KR101023538 B1 KR 101023538B1 KR 1020090005408 A KR1020090005408 A KR 1020090005408A KR 20090005408 A KR20090005408 A KR 20090005408A KR 101023538 B1 KR101023538 B1 KR 101023538B1
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- C07C323/57—Thiols, sulfides, hydropolysulfides or polysulfides substituted by halogen, oxygen or nitrogen atoms, or by sulfur atoms not being part of thio groups containing thio groups and carboxyl groups bound to the same carbon skeleton having the sulfur atoms of the thio groups bound to acyclic carbon atoms of the carbon skeleton the carbon skeleton being further substituted by nitrogen atoms, not being part of nitro or nitroso groups
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Abstract
본 발명은 아미노산중에서 황을 함유하는 엘-시스틴(L-Cystine)을 추출제조하는 방법을 개시한다. 엘-시스틴은 건강증진, 간기능개선용 식품첨가물과 원료의약품으로 사용되는 뛰어난 효과가 있다. The present invention discloses a method for extracting L-Cystine containing sulfur among amino acids. L-cystine has the excellent effect of being used as food additives and drug substance for health promotion and liver function improvement.
아미노산, 엘-시스틴, 아세틸시스테인, 건강증진, 간기능 개선 Amino acids, L-cystine, acetylcysteine, health promotion, liver function improvement
Description
본 발명은 엘-시스틴(L-Cystine)의 제조방법에 관한 것으로, 더욱 구체적으로는 엘-시스테인 및 그 분리여액 그리고 아세틸시스테인 및 그 분리여액으로부터 엘-시스틴을 각각 분리 및 정제하여서 회수하는 방법에 관한 것이다.The present invention relates to a method for preparing L-Cystine, and more particularly, to a method for recovering L-cystine from L-cysteine and its filtrate and acetylcysteine and its filtrate, respectively. It is about.
종래 엘-시스틴(L-Cystine)은 대부분을 머리카락에 함유하고 있는 케라틴단백질을 산가수분해하여 추출 분리하여왔다. 즉, 머리카락을 일정비율의 염산 용액에 침적하여, 100∼105℃에서 가온하여 머리카락을 용해하고 이 용해액에서 모래, 고무, 핀 등 불순물을 여과망을 이용하여 여과 제거한 다음 그 분리 여액을 100∼105℃에서 6∼7시간 가수분해하여 머리카락의 함유성분 중 케라틴단백질을 아미노산 형태로 분해하여 얻었다. Conventional L-cystine (L-Cystine) has been extracted and separated by acid hydrolysis of keratin protein that contains most of the hair. That is, the hair is immersed in a predetermined ratio of hydrochloric acid solution, heated at 100 to 105 ° C to dissolve the hair, and impurities, such as sand, rubber, and pin, are filtered out from the solution using a filtering network, and the filtrate is separated from 100 to 105. It was hydrolyzed at 6 ° C. for 6 to 7 hours to obtain keratin protein in the amino acid form.
여기에 활성탄을 처리하여 탈색여과한 다음 암모니아로 pH 4.5∼5.0으로 중화하여 조시스틴을 얻을 수 있다. The treated carbon can be treated with decolorized filtration, and then neutralized with ammonia to pH 4.5-5.0 to obtain jocithin.
이러한 조시스틴은 불순물과 기타의 아미노산을 함유하고 있어서 한번 더 정제과정을 거쳐야만 하였다, These chocystins contained impurities and other amino acids, which had to be purified once more.
즉, 조시스틴을 염산용액에 더 용해하여 활성탄으로 탈색 여과하고 pH를 1.0∼2.5 로 조절하여 기타 아미노산 및 불순물을 제거하여 왔다. That is, the crude cysteine was further dissolved in hydrochloric acid, decolorized and filtered with activated carbon, and the pH was adjusted to 1.0 to 2.5 to remove other amino acids and impurities.
종래 L-시스틴의 제조방법으로서, L-세린을 NaOH용액을 첨가하여 PH 8.5로 적정화한 다음 L-시스테인을 형성하고 이를 디에틸슬폭시드 존재하에 산화하여 제조하는 방법이 국내특허 공보 90-8249호에 공지되어 있으며, 또 다른 제조방법으로서 β-치환된 L-알라닌을 트립토판 신타아제 존재하에서 효소반응시킴을 특징으로 하는 L-시스틴과 L-시스테인 혼합물을 제조하는 방법이 국내특허 공보 89-4021호에 각각 공지되어 있다.As a conventional method for preparing L-cystine, a method of preparing L-serine by optimizing L-serine to PH 8.5 by adding NaOH solution and then forming L-cysteine and oxidizing it in the presence of diethylsulfoxide is disclosed in Korean Patent Publication No. 90-8249. As known in the art, another method for preparing L-cystine and L-cysteine mixture, which is characterized by enzymatic reaction of β-substituted L-alanine in the presence of tryptophan synthase, is disclosed in Korean Patent Publication No. 89-4021. Each is known in the art.
또, 이와 관련 기술로서 화장품용 L-시스틴의 펄 제조방법으로 L-시스테인을 천역색소용액에 투입하여 용해하고 산과 알카리를 가하여 PH3~9로 조절한 후 20~50℃에서 혼화하여 되는 L-시스틴 펄 조성물 제조 방법이 국내특허공보 89-1877호에 개시되어 있다.In addition, as a related technology, L-cystine is added to dissolve L-cysteine in a natural dye solution using a pearl production method of cosmetic L-cystine, and adjusted to PH3-9 by adding acid and alkali, and then mixed at 20-50 ° C. A method for preparing a pearl composition is disclosed in Korean Patent Publication No. 89-1877.
한편, 엘-시스틴을 전기환원에 의하여 엘-시스테인을 생산하기도 하였는데, 이와 같은 엘-시스테인은 파마약의 원료 및 간기능 개선, 진해거담제의 유도체 원료로 사용되고 있으며, 이 엘-시스테인 및 그 분리여액에서 엘-시스틴을 추출할 때에는 엘-시스테인 분리여액에 엘-시스테인의 함유량의 몰비율 만큼 과산화수소(H2O2)를 천천히 투입하면 엘-시스테인이 엘-시스틴으로 산화되는데 여기서 엘-시스틴을 추출하여 왔다.On the other hand, L-cystine was produced by the electro-reduction of the el-cysteine, such el-cysteine is used as a raw material for the pharmaceutical and liver function, derivative material of antitussive expectorant, the el-cysteine and its filtrate When extracting el-cystine at, slowly add hydrogen peroxide (H 2 O 2 ) to the el-cysteine filtrate as much as the molar ratio of the content of el-cysteine, and then el-cysteine is oxidized to el-cystine. Has come.
상기에서 엘-시스테인의 제조과정 또는 아세틸시스테인의 생산과정에서 남은 분리여액은 대부분 폐기되어 환경오염의 원인이 되어왔던 결함이 있었다.The separation filtrate remaining in the production process of the L-cysteine or the production process of acetylcysteine is mostly a defect that has been a cause of environmental pollution.
그러나, 본 발명의 목적은 상기 폐기되는 엘-시스테인 및 아세틸시스테인 여액으로부터 건강증진 및 간기능개선 및 뛰어난 효과가 있는 고순도의 엘-시스틴(L-Cystine)을 회수·제조하는데 있다.However, it is an object of the present invention to recover and manufacture high purity L-Cystine, which is effective in promoting health and improving liver function and excellent effects from the discarded L-cysteine and acetylcysteine filtrate.
본 발명의 상기 목적은 엘-시스틴으로부터 환원에 의해 얻어진 엘-시스테인의 합성유도체인 아세틸시스테인의 버려지는 분리 여액으로부터 산분해, 산화, 탈색, 정제 과정을 거쳐 엘-시스틴을 추출, 회수함으로써 달성하였다.The object of the present invention was achieved by extracting and recovering L-cystine from acidic separation, oxidation, decolorization, and purification from the discarded separation filtrate of acetylcysteine, a synthetic derivative of L-cysteine obtained by reduction from L-cystine. .
즉, 엘-시스틴의 환원에 의해 생성된 엘-시스테인을 아세틸화하여 수득된 아세틸시스테인은 기침, 가래에 효과가 있는 진해거담제로 널리 사용되고 있다. 아세틸시스테인을 합성 추출한 후에 남은 분리여액에는 미회수된 아세틸시스테인이 있는데, 순환 농축 공정을 통해 일부 아세틸시스테인은 회수되기도 하지만, 경제성 또는 회수율을 이유로 대부분 폐기하고 있는 실정이다. That is, acetylcysteine obtained by acetylating L-cysteine produced by the reduction of L-cystine is widely used as an antitussive expectorant for coughing and sputum. The remaining filtrate remaining after the synthetic extraction of acetylcysteine is unrecovered acetylcysteine. Although acetylcysteine is recovered through a circulating concentration process, it is mostly disposed of due to economical efficiency or recovery rate.
그러나, 미회수된 분리여액에는 다량의 아세틸시스테인이 함유되어 있어 회수할 필요성이 있으며, 미회수 아세틸시스테인 분리여액을 산성으로 하고 가수분해하면 아세틸기가 분해되어 엘-시스테인으로 변화된다. 이렇게 생성된 엘-시스테인을 다시 과산화수소 등을 이용하여 산화시킨 다음 탈색여과 후 중화시켜 고순도의 엘-시스틴을 회수·제조할 수 있다.However, the unrecovered separation filtrate contains a large amount of acetylcysteine and needs to be recovered. When the unrecovered acetylcysteine separation filtrate is acidified and hydrolyzed, the acetyl group is decomposed and converted into el-cysteine. The L-cysteine thus produced is oxidized again with hydrogen peroxide, and then neutralized after decolorization filtration to recover and manufacture high purity L-cystine.
본 발명은 종래의 머리카락으로부터 엘-시스틴을 제조하는 공정에서 폐기되었던 엘-시스테인 및 아세틸시스테인 분리 여액을 산가수분해, 산화, 중화 등의 간단한 공정을 통해 고순도의 엘-시스틴을 회수할 수 있는 효과가 있을 뿐만 아니라, 환경오염을 줄일 수 있는 뛰어난 효과가 있다.The present invention has the effect of recovering high-purity el-cystine through a simple process such as acid hydrolysis, oxidation, neutralization of the el-cysteine and acetylcysteine separation filtrate, which was discarded in the process of producing el-cystine from the conventional hair. Not only that, there is an excellent effect to reduce environmental pollution.
본 발명은 케라틴단백질인 머리카락으로부터 산가수분해를 통해 엘-시스틴을 제조하는 공정에서 엘-시스테인 및/또는 아세틸시스테인을 포함하는 분리여액으로부터 엘-시스틴을 추출·회수하는 방법을, 바람직한 실시예를 통하여 상세히 설명한다. The present invention provides a method for extracting and recovering L-cystine from a filtrate containing L-cysteine and / or acetylcysteine in the process of producing L-cystine through acid hydrolysis from keratin protein hair. It will be described in detail through.
엘-시스틴은 물에 대한 용해도가 25℃에서 0.01g/100mL 로 극히 낮고 온도에 따른 용해도의 변화도 거의 없기 때문에 온도를 60∼80℃ 유지하면서 추출, 분리할 수 있다. 상기 온도를 유지함으로써 엘-시스틴의 결정 비중을 향상시킬 수 있는 장점도 있다.L-cystine has very low solubility in water of 0.01g / 100mL at 25 ° C and little change in solubility with temperature, so it can be extracted and separated while maintaining the temperature of 60-80 ° C. Maintaining the temperature also has the advantage of improving the specific gravity of the L-cystine.
이하, 본 발명의 바람직한 실시예를 통하여 발명의 구체적인 구성을 상세히 설명한다.Hereinafter, the specific configuration of the invention through the preferred embodiment of the present invention will be described in detail.
실시예 1 : 머리카락으로부터 엘-시스틴의 추출정제Example 1 Extraction of L-cystine from Hair
머리카락 300g에 35% 염산 450mL와 정제수 100mL 혼합액을 투입하여 100∼104℃에서 6시간동안 산가수분해한 후에 활성탄 10g을 넣고 45℃에서 3시간 정도 탈색여과를 하고, 여과액량을 1,000mL 되게 정제수를 투입하였다. 이 후 암모니아수에 의해 pH 4.5∼5.0로 조정하여 엘-시스틴 조결정을 얻었다. Into 300g of hair, 450 ml of 35% hydrochloric acid and 100 ml of purified water were added and acid hydrolyzed at 100-104 ° C. for 6 hours, 10 g of activated carbon was added and decolorized filtered at 45 ° C. for about 3 hours, and the filtrate was 1,000 mL. Input. Thereafter, the pH was adjusted to 4.5 to 5.0 with ammonia water to obtain an L-cystine crude crystal.
이 조결정을 분리회수하여 8% 염산 용액에 용해시켜서 용액 총량이 700mL로 되게 하고, 다시 활성탄 4g을 투입하여 탈색 여과하였다. 이 여과액을 가온하여 60℃을 유지하고 암모니아수에 의해 pH 1.2∼2.5로 조정하여 60∼80℃ 유지하고 2시간이상 교반하여 엘-시스틴을 석출, 분리하여서 엘-시스틴 15g을 얻을 수 있었다. The crude crystals were separated and recovered and dissolved in an 8% hydrochloric acid solution so that the total amount of the solution was 700 mL. Then, 4 g of activated carbon was added and decolorized and filtered. The filtrate was kept at 60 ° C., adjusted to pH 1.2-2.5 with ammonia water, maintained at 60-80 ° C., stirred for 2 hours or more to precipitate and separate L-cystine, thereby obtaining 15 g of L-cystine.
실시예 2 : 엘-시스테인 및 그 분리여액으로부터 엘-시스틴의 회수Example 2 Recovery of L-cystine from L-cysteine and its Filtrates
엘-시스테인의 분리여액 200mL에 엘-시스테인 함유량의 몰비에 해당하는 34% 과산화수소 11mL를 천천히 투입하여 3시간 이상 산화시켰다. 엘-시스테인의 검출 여부를 닌히드린 정성 반응으로 확인하고 산화를 완료하였다. 200 mL of the el-cysteine filtrate was slowly added with 11 mL of 34% hydrogen peroxide corresponding to the molar ratio of the el-cysteine and oxidized for 3 hours or more. The detection of L-cysteine was confirmed by the ninhydrin qualitative reaction and the oxidation was completed.
이 반응액에 활성탄 1g을 투입하여 45∼55℃에서 3시간동안 탈색 여과하고 25% 암모니아수 42mL를 첨가하여 엘 시스틴의 등전점인 pH 4.9로 조정한 다음, 엘-시스틴 조결정을 분리하였다.1 g of activated carbon was added to the reaction solution, decolorized and filtered at 45 to 55 ° C. for 3 hours, and 42 mL of 25% aqueous ammonia was added thereto to adjust the pH to 4.9, which is the isoelectric point of El cystine, and then the L-cystine crude crystal was separated.
상기 조결정은 탈색 정제를 위해 물 200mL의 비이커에 투입한 후 35% 염산 34mL를 투입하여 완전히 용해시켰다. 다시 활성탄 1g을 투입하여 45∼55℃에서 3시간동안 탈색 여과하고, 여과액의 액량을 총 800mL로 증량하기 위하여 물 200mL를 추가하여 60℃로 가온하였다. 60℃로 가온시킨 후에 25%암모니아수 230mL를 투입하여 pH 1.2로 조정하고 60∼80℃ 유지하여 2시간이상 교반하여서 엘-시스테인을 충분히 석출시켰다. The crude crystals were completely dissolved by adding a beaker of 200 mL of water to a decolorized tablet and adding 34 mL of 35% hydrochloric acid. Again, 1 g of activated carbon was added and decolorized and filtered at 45 to 55 ° C. for 3 hours, and 200 mL of water was added to warm the solution to a total of 800 mL. After warming to 60 ° C., 230 mL of 25% ammonia water was added thereto, adjusted to pH 1.2, maintained at 60 to 80 ° C., and stirred for 2 hours or longer to sufficiently precipitate L-cysteine.
이를 분리 여과하여 엘-시스틴을 103℃ 열풍건조기에서 3시간 이상 건조하여 27g의 엘-시스틴을 얻었다(도 1 참조).This was filtered and el-cystine was dried in a 103 ° C. hot air dryer for 3 hours or more to obtain 27 g of L-cystine (see FIG. 1).
실시예 3 : 아세틸시스테인 및 그 분리여액으로부터 엘-시스틴의 회수Example 3 Recovery of L-cystine from Acetylcysteine and its Filtrates
아세틸시스테인 분리여액 200mL에 35% 염산 20mL를 투입하여 반응액의 염산 농도가 20%로 되도록 조정하였다. 이 용액을 산가수분해가 가능하도록 환류냉각 장치가 연결된 분해조에 넣고 heating mentle로 103℃에서 3시간 산가수분해를 완료하고 냉각하였다(도 2 참조).20 mL of 35% hydrochloric acid was added to 200 mL of the acetylcysteine separation filtrate, and the reaction solution was adjusted so that the concentration of hydrochloric acid was 20%. The solution was placed in a digester connected to a reflux condenser to enable acid hydrolysis, and the acid hydrolysis was completed for 3 hours at 103 ° C. with a heating mentle and cooled (see FIG. 2).
가수분해액에 함유되어 있는 엘-시스테인의 몰비에 해당하는 34% 과산화수소 11mL를 천천히 투입하여 3시간 이상 산화시켜 엘-시스테인의 검출 여부를 닌히드린 정성 반응으로 확인하여 산화를 완료한 다음, 상기 실시예 2와 동일한 공정을 거쳐서 27g의 엘-시스틴을 얻었다.11 ml of 34% hydrogen peroxide corresponding to the molar ratio of L-cysteine contained in the hydrolyzate was slowly added and oxidized for 3 hours or longer to confirm the detection of L-cysteine by a ninhydrin qualitative reaction to complete oxidation. 27 g of L-cystine was obtained through the same process as in Example 2.
한편, 상기 실시예 2 내지 3에 있어서, 조결정 분리 과정을 생략하고 탈색 여과하여 총액량을 800mL로 조정한 후에 60℃로 가온하고, 25% 암모니아수를 투입하여 pH 1.2∼2.5로 조정한 다음, 60∼80℃로 유지하면서 2시간이상 교반하여 엘-시스틴을 석출, 분리하여 얻을 수도 있음은 물론이다.On the other hand, in the above Examples 2 to 3, the crude crystal separation process was omitted, decolorized filtration to adjust the total liquid amount to 800 mL, then warmed to 60 ℃, 25% ammonia water was added to adjust the pH to 1.2 to 2.5, Of course, it is also possible to precipitate and separate L-cystine by stirring for 2 hours or more while maintaining at 60 to 80 ℃.
도 1은 엘-시스테인의 산화 반응 공정도이다.1 is a flowchart of oxidation reaction of L-cysteine.
도 2는 아세틸시스테인의 가수분해 반응 고정도이다. 2 is a high accuracy of the hydrolysis reaction of acetylcysteine.
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| JPS58188846A (en) * | 1982-04-28 | 1983-11-04 | Nippon Rikagaku Yakuhin Kk | Separation of cystine or cysteine and tyrosine |
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| JPS58188846A (en) * | 1982-04-28 | 1983-11-04 | Nippon Rikagaku Yakuhin Kk | Separation of cystine or cysteine and tyrosine |
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