Proteases ficin

One of the most characteristic differences between papain and the other sulfhydryl proteases, ficin and bromelain, is the absence of carbohydrate in papain. Glycopeptides have been isolated from ficin (48) and bromelain (49, 50, 51, 52). In the case of bromelain the carbohydrate moiety composed of mannose, xylose, fucose, and N-acetylglucosamine is covalently linked to an asparagine residue of the peptide chain through a glucosamine component of the sugar moiety (51,52). 

Photographic industry Protease (ficin) Dissolve gelatin off scrap film, allowing recovery of its silver content. 

Proteases (ficin from figs, actinidin from kiwi, papain from papaya, bromelain from ananas)... 

Like other proteases, ficin may cause contact allergies in certain individuals, and large oral doses are reported to cause catharsis (merck). 

Corresponding equations were derived for the cysteine proteases ficin, actinidin, bromelain B and D, and the serine proteases subtilisin, chymotrypsin, and trypsin. In all cases, the coefficient of the electronic a term is around 0.4-0.7. Whereas the other regression coefficients in equations (16) and (17) are also relatively similar, the constant terms of both equations differ by about 1.8 log units, which indicates that the lower lipophilicity of the mesyl group, as compared with a much more lipophilic benzoyl group, is responsible for the lower binding affinities of the mesyl amides. To prove this hypothesis, a series of (4-X-Phe)-CONHCH2COO-pyrid-3-yl analogs 12 was synthesized and tested. As expected, lipophilicity determines the structure-activity relationship in this part of the molecules (equation IS). " " ... 

Soya Proteins. Early attempts to make albumen substitutes from soya protein also ran into problems. A bean flavour tended to appear in the finished product. A solution to these problems has been found. Whipping agents based on enzyme modified soy proteins are now available. The advantage of enzymatic modification is that by appropriate choice of enzymes the protein can be modified in a very controlled way. Chemical treatment would be far less specific. In making these materials the manufacturer has control of the substrate and the enzyme, allowing the final product to be almost made to order. The substrates used are oil-free soy flakes or flour or soy protein concentrate or isolate. The enzymes to use are chosen from a combination of pepsin, papain, ficin, trypsin or bacterial proteases. The substrate will be treated with one or more enzymes under carefully controlled conditions. The finished product is then spray dried. 

Taschini, P. and MacDonald, D. (1987) Protease digestion step in immunohistochemical procedures ficin as a substitute for trypsin. Lab. Med. 18, 532-536. 

Plant Proteases. These include the well known proteases papain, bromelain and ficin. Most plant enzymes are available as comparatively unpurified powder extracts, although papain is notable for being available in a stabilized and purified liquid form. Prospects for increased supply of plant enzymes, in response to greater use in traditional applications or for new processes, depend on several factors. Tlie influence of cultivation conditions, growth cycle and climate requirements make new supplies long term projects. 

The greatest variety of industrial enzymes are presently derived from microbial sources, with a lesser diversity coming from plant and animal sources 34), Enzymes derived from plant sources and which are used extensively in the food industry include papain, bromelain, ficin, and amylases. Animal enzymes of economic importance include trypsins, lipases, and gastric proteases. 

In enzymes, the most common nucleophilic groups that are functional in catalysis are the serine hydroxyl—which occurs in the serine proteases, cholinesterases, esterases, lipases, and alkaline phosphatases—and the cysteine thiol—which occurs in the thiol proteases (papain, ficin, and bromelain), in glyceraldehyde 3-phosphate dehydrogenase, etc. The imidazole of histidine usually functions as an acid-base catalyst and enhances the nucleophilicity of hydroxyl and thiol groups, but it sometimes acts as a nucleophile with the phos-phoryl group in phosphate transfer (Table 2.5). 

PROTEASE. A proteolytic enzyme that weakens or breaks the peptide linkages in proteins, They include some of the more widely known enzymes such as pepsin, trypsin, ficin, bromelm, papain, and rennin. Being water soluble they solubilize proteins and are commercially used for meat tendenzers, bread baking, and digestive aids. 

Bromelain differs from (be other cysieinyl proteases papain and ficin in its 140-told difference of Itcat for the BAEK and BAA hydrolysis, suggesting a difference in the mechanism of catalysis for both substrates [37]. For BABE hydrolysis, deacylation is predominantly the rate-limiting step, while for BAA hydrolysis (he acylation is rate limiting [42]. However, Wharton et aL [43] explained the differences in kcot for BAEE and BAA hydrolysis a gauming (hat nonproductive binding plays a role in catalysis. 

Source. Enzymes for food applications come from all three kingdoms plant, animal, and microbial. Traditionally used plant and animal enzymes are the plant proteases such as papain, ficin and bromelain, plant amylases from malt, and animal rennin which is used in cheese manufacture. Microbial cells are the usual and most promising future source of industrial enzymes. Estimates of the number of microorganisms in the world tested as potential sources of enzymes fall around 2% with only about 25 organisms, including a dozen or so fungi, currently used for industrial enzymes. 

Cysteine proteases are so called because of a critical cysteine involved (together with an adjacent histidine) in the catalytic mechanism. Cysteine proteases include papain-related proteases, calpain-related proteases and the caspases. Papain-like cysteine proteases include the plant enzymes actinidin, aleurain, bromelain, caricain, chymopapain, ficin and papain and the lysosomal cathepsins B, C, H, K, L and S. Cathepsin C is multimeric (MW -200,000), but the other papain-related proteases are monomeric with MWs of about 20,000-35,000. While cathepsin C is a dipeptidyl aminopeptidase, the other enzymes are endopeptidases. Cathepsin B is an endopeptidase and a dipeptidyl carboxypeptidase. Cathepsin H is an endopeptidase and an aminopeptidase. In higher animals, cathepsin B generates peptides from antigens for presentation to T cells by the major histocompatibility... 

Among the proteolytic enzymes, the plant proteases are the most widely used in the food industry. Most of the plant proteases which have been studied are characterized by a free sulfhydryl group which is essential for their activity. The most important of these so-called sulfhydryl or thiol proteases are papain, ficin, and bromelain. Since the literature on these enzymes has been the subject of several recent reviews (i, 2, 3, 4), major emphasis is placed in this presentation on the use of these enzymes in the food industry. Some of the more recent developments relating to the structure and function of the sulfhydryl proteases are discussed. 

Since several excellent books and monographs are available on this subject 11, 12, 13, 14, 15), only a brief survey is presented here. The principal commercial uses of the sulfliydryl proteases are summarized in Table I. Although papain is used mainly for these purposes, ficin and bromelain also have been used with essentially the same results. 

Inhibition. Since papain, ficin, and bromelain are all enzymes whose activity depends on a free SH group, it is to be expected that all thiol reagents act as inhibitors. Thus, a-halogen acids or amides and N-ethyl-maleimide irreversibly inhibit the thiol proteases. Heavy metal ions and organic mercurial salts inhibit in a fashion that can be reversed by low molecular weight thiols, particularly in the presence of EDTA which... 

PINEAPPLE, Ananas comosm (L). Merr., Family Bromdiaceae and PAPAYA, Carica papaya, L., Family Carica-ceae are two plants which contain proteolytic enzymes bromelain in pineapple and papain in unripe papaya fruits. These two are proteases and can degrade protein in meat in cases where there is a deficiency of digestive enzymes. Papain is widely used as a meat tenderiser as are ficin from Ficus glabra and the bromelains. It is also used in more purified form (Chymopapain) in chemonucleolysis to shrink ruptured or slipped vertebral discs. 

M05A B Antiinflammatory enzymes A variety of animal and plant proteases are used to reduce inflammation and swellings in wounds and abscesses after minor dental surgery, for example. The plant enzymes include papain, bromelains and ficin. These and animal enzymes such as trypsin and chy-motrypsin (pancreatic enzymes) are used as debriding agents in burn tissue, pus etc. 

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