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Mini Review Collagen extraction process 1 Schmidt, M. Received: 18 March Collagen is a fibrous protein which is dominant in the connective tissue of animals; it has a wide Received in revised form: range of applications in the food, pharmaceutical, cosmetic and photographic industries, among 30 September others. There is a growing interest in the extraction process of collagen and its derivatives due Accepted: 13 November to the growing tendency to use this protein to replace synthetic agents in various industrial processes, which results in a greater appreciation of the by-products from animal slaughter.

Keywords Collagens characteristics depend on the raw material and the extraction conditions, which subsequently determine its application. The most commonly used extraction methods are based Hydrolysis on the solubility of collagen in neutral saline solutions, acid solutions, and acid solutions with Proteases added enzymes.

Recently, the use of ultrasound, combined with these traditional processes, has Ultrasound By-products proven effective in increasing the extraction yield. The objective of this review is to address the different collagen extraction processes, from raw materials to the use of combinations of chemical and enzymatic processes, as well as the use of ultrasound.

The information outlined in this article have been collected from different national and international journals in Agricultural Sciences e Science and Food Technology, using four bibliographic databases and also some books of renowned authors.

Were selected articles published between and , to address the different collagen extraction processes have been studied. All Rights Reserved. Introduction provide a greater appreciation of the by-products of animal slaughter Karim and Bhat, ; Gmez- Collagen is the dominant protein in connective Guilln et al.

Thus, it is The main sources of collagen are the skin, tendons, necessary to determine the appropriate extraction cartilage and bones. Some studies have addressed process for each raw material in order to obtain the ways of obtaining collagen from different animal best performance and the best collagen characteristics sources, such as fish and birds, as alternatives to bovine for the desired application.

There is great demand in the food industry for There is growing interest in the processes used to collagen and gelatin because of their high protein extract collagen and its derivatives due to the growing content and their functional properties, such as water tendency to use this protein in place of synthetic absorption capacity, gel formation, and the ability agents in various industrial processes, and also to to form and stabilize emulsions.

In the biomedical. Email: rosacrisprestesdornelles outlook. Several studies al. Several of these have examined collagen in order to obtain bioactive by-products have been studied, including the Achilles compounds with antimicrobial, antioxidant and anti- tendon Li et al. Lin et al. The objective of this review is to address the Recent research has examined alternative different collagen extraction processes, from raw sources for the extraction of collagen, with particular materials to the use of combinations of chemical and emphasis on fish by-products Muralidharan et al.

This is mainly due to religious restrictions, journals in Agricultural Sciences e Science and Food regarding the non-consumption of pork by Muslims Technology, using four bibliographic databases and and Jews, and also the risk of bovine spongiform also some books of renowned authors.

Were selected encephalopathy BSE Kaewdang et al. The yield of japonicus Kim et al. According to Bhaskar et Li et al. Despite the extraction of marine collagen is as delicacies that command high prices Toldr et easy and safe this collagen presents some limitations al.

However, the majority of by-products in their application, due to its low denaturation are not suitable for human consumption due to temperature Subhan et al. As a result, a potential source The extraction of collagen from poultry slaughter of income is lost, and the cost of disposal of these waste has also been researched, but with less products has become increasingly high Jayathilakan emphasis because of the risk of the transmission of et al.

Nevertheless, there is a growing avian influenza Saito et al. Studies have awareness that these by-products can represent been performed regarding emu skin Dromaius valuable resources if they are used properly. Obtaining those b etc. Other higher added value and reduced environmental types of collagen are only present in very small damage Toldr et al.

It is an important component in the support structures in Collagen extraction process vertebrates and invertebrates. Chemical hydrolysis is more commonly ; Voet et al. In poultry and fish it plays a similar role to products with high nutritional value and improved that of invertebrates and is an important component functionality are required Martins et al. Moreover, enzymatic processes generate less waste Collagen molecules are about nm long, with and may reduce the processing time, but they are a molar mass of , Da; they are stabilized by more expensive.

To extract collagen it is necessary to hydrogen bonds and intermolecular bonds Silva remove numerous covalent intra- and intermolecular and Penna, , which are composed of three cross-links, which primarily involves residues of helical polypeptide chains, each with about lysine and hydroxy-lysine, ester bonds and other amino acids, which are called an chain.

The chains bonds with saccharides, all of which makes the become entangled, forming a stable triple helix process quite complex Ran and Wang, The triple helix molecules Before the collagen can be extracted a pre- have terminal globular domains and are called treatment is performed using an acid or alkaline procollagen.

These globular regions are cleaved process, which varies according to the origin of the in varying degrees to give a polymerized structure raw material. The pre-treatment is used to remove tropocollagen , which is the basic unit of collagen. The most commonly used hydrophobic and electrostatic interactions Nelson extraction methods are based on the solubility of and Cox, ; Damoradan et al.

The amino acid sequence in collagen is generally a repetitive tripeptide unit Pre-treatment Gly-X-Y , where X is frequently Pro and Y is Hyp Due to the nature of the cross-linked collagen Nelson and Cox, As been reported, which are classified according to a result, a mild chemical treatment is necessary to their structure into: striatum fibrous , non-fibrous break these cross-links before extraction Schreiber network forming , microfibrillar filamentous and and Gareis, To this end, diluted acids and those which are associated with fibril Damoradan et bases are employed, and the collagen is subjected al.

It consists of three polypeptide chains, two of In the acidic form of pre-treatment the raw material which are identical, which are called chain 1 I and is immersed in acidic solution until the solution 2 I , and which are composed of different amino penetrates throughout the material. As the solution acids. Type II collagen occurs almost exclusively penetrates the structure of the skin at a controlled in cartilage tissue and it is believed that the 1 II temperature it swells to two or three times its initial subunit is similar to the 1 I subunit.

Table 1. Some procedures used in the extraction of collagen from animal waste reported in the literature. This raw materials with less intertwined collagen fibers, process is used for thicker materials that require a such as porcine and fish skins Almeida, b.

The hydrolysates that were produced in Ctenopharyngodon idella. Concentrations of different conditions showed distinct properties. The NaOH from 0. The products obtained and 20C. However, 0. The extractions with acidic pH and high 20C. In addition to the use of acids and bases, temperature produced collagen with reduced molar enzymes or chemicals may also be used to cleave the mass.

In general, the hydrolysates obtained with cross-linked bonds to obtain products with different acidic pH formed firmer gels. The water retention characteristics Schrieber and Gareis, The three tested variables use of this method is limited Yang and Shu, Increased temperature and lactic acid, and inorganic acids such as hydrochloric concentration of acetic acid increased the yield to acid.

However, organic acids are more efficient than a certain value, which then decreased. The optimal inorganic acids Skierka and Sadowska, ; Wang conditions to obtain the highest yield of acid-soluble et al. Organic acids are capable of solubilizing collagen in skin from grass carp were: an acetic acid non-crosslinked collagens and also of breaking some concentration of 0. Therefore, acidic solutions, bladder of barramundi Lates calcarifer was especially acetic acid, are commonly used to extract extracted by Sinthusamran et al.

The pre- collagen. The acid-soluble collagen pre-treated material is added to the acid solution, from the swim bladder showed a higher yield In both cases the collagen was identified as on the raw material Wang et al. Both the skin and the swim bladder of barramundi After the extraction stage, a filtering is performed showed potential for collagen extraction. To obtain alkaline pre-treatment and extraction with acetic collagen powder, the filtrate is usually subjected acid for grass carp Ctenopharyngodon idella can to precipitation with NaCl.

The precipitate is then be performed at a temperature range of 4 to 20C collected by centrifugation and subsequently re- instead of the commonly used low temperature of dissolved in a minimum volume of 0. In this case, there was no significant loss of and then dialyzed in 0. In general, chemical hydrolysis processes seek Kittiphattanabawon et al.

The extraction was initially For the extraction of collagen by enzymatic performed with acetic acid for 48 hours at 4C. The mixture is continuously the acid-extracted collagen. Furthermore, the spectra stirred for about 48 hours at 4C followed by filtration of both collagens that were obtained by FTIR were Li et al.

The method of extraction can influence the Woo et al. Pre-treatment was performed with NaOH well as water retention and emulsification capacity. Subsequently, digestion enzyme, temperature, time and pH , the pre- with pepsin 0. The optimal extraction conditions were Thus it is necessary to perform a partially obtained with a pre-treatment of 0. This factor has emphasized the use Acipenser schrenckii using NaCl, acetic acid and of selected animal or vegetable proteolytic enzymes, pepsin for extraction.

Initially, the skin was pre- such as trypsin, chymotrypsin, pepsin, pronase, treated with NaCl and Tris-HCI and then the saline- alcalase, collagenases, bromelain and papain Gmez- soluble collagen was extracted SSC in 0.

After the extraction with salt, substrate protein. In addition, enzymatic hydrolysis the residue was suspended in 0. The degree of hydrolysis, moderate conditions of action, material that was insoluble in acetic acid was used and lower salt content in the final hydrolyzate. All the isolated collagens Despite the high cost of enzymatic hydrolysis, maintained a triple helix structure and were mainly the fact that it results in lower levels of waste, better type 1 collagen, with similar morphology and amino control of the process and higher yield justifies the acid profiles.

The spectroscopic analysis in the mid- use of enzymes. Ultrasound has been used successfully in collagen remained intact, even after the ultrasonic collagen extraction by reducing the processing time treatment. In addition, higher than 16 kHz Chemat and Khan, The the yield of collagen from the skin of Japanese sea effects of ultrasound in liquid systems are mainly bass Lateolabrax japonicus increased greatly with due to the phenomenon known as cavitation Hu et increased treatment time and amplitude of ultrasound.

During sonication, cavitation bubbles are However, studies of the effect of ultrasound quickly formed, which then suffer a violent collapse, on enzyme activity are still very limited Li et al. This ; Yu et al. Yu et al. Extraction with ultrasound did not alter the time may give rise to elevated temperatures and shear major components of the collagen, more specifically strength, as well as high pressures within the medium the 1, 2 and chains. Conventional extraction was performed with pepsin 50 Umg-1 of sample in acetic acid for 48 hours.

For Conclusions the extraction with ultrasound the same conditions were used, but the times of extraction with ultrasound This review examined differences in collagen 3 to 24 h and pepsin 24 to 45 hours were varied, extraction processes because this is a key step in resulting in a total of 48 hours of treatment.

The achieving higher yield, purity and structural integrity combination of ultrasound with pepsin resulted in a of this protein, as well as saving time and reducing greater efficiency of collagen extraction, reaching a process costs.

Among the methods of extraction yield of 6.

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Embed Size px x x x x O Instituto Nacional de Cincia e Tecnologia de Biologia Estrutural e Bioimagem INBEB uma iniciativa pioneira com a misso de criar e consolidar uma infraestrutura tcnico-cientfica que permita o estudo das estruturas de sistemas biolgicos, desde o nvel macromolecular at o organismo inteiro, lanando mo das tcnicas mais avanadas e de mais alta resoluo possvel. O INBEB promove a interdisciplinaridade, fazendo com que reas convencionais como biofsica, parasitologia, microbiologia, imunologia, bioqumica, farmacologia, qumica e computao tenham suas fronteiras estendidas. Isto permite a maior interao entre grupos para solucionar diversos problemas biolgicos.

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Mini Review Collagen extraction process 1 Schmidt, M. Received: 18 March Collagen is a fibrous protein which is dominant in the connective tissue of animals; it has a wide Received in revised form: range of applications in the food, pharmaceutical, cosmetic and photographic industries, among 30 September others. There is a growing interest in the extraction process of collagen and its derivatives due Accepted: 13 November to the growing tendency to use this protein to replace synthetic agents in various industrial processes, which results in a greater appreciation of the by-products from animal slaughter. Keywords Collagens characteristics depend on the raw material and the extraction conditions, which subsequently determine its application. The most commonly used extraction methods are based Hydrolysis on the solubility of collagen in neutral saline solutions, acid solutions, and acid solutions with Proteases added enzymes. Recently, the use of ultrasound, combined with these traditional processes, has Ultrasound By-products proven effective in increasing the extraction yield.

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