Ficin papain

Malus domestica (apple) (Rosaceae) [immature fruit] Apple cystatin (11 kDa phytocystatin) Bromelain, Ficin, Papain [0.2 nMl [170]... 

Tappel (99) reported on the hydrolytic activity of various enzymes. They found that the relative hydrolysis of muscle proteins increased in the following order pepsin, Rhozyme A-4, ficin, papain, bromelain, protease 15, Rhozyme P-11, and trypsin. Wang et al. (100) observed that papain was twice as active as ficin towards elastin, a minor component of connective tissue. Ficin and bromelain had equal enzyme activity towards collagen, a major component of connective tissue. Kang and Rice (101) studied the effects of various tenderizing enzymes on water-soluble sarcoplasmic proteins, salt-soluble myofibrillar proteins, and the insoluble stromal proteins. Table VII tabulates the results of some of these studies. 

Thiol proteinase inhibitor 90,000 Ficin, papain, cathepsin B and bromelain 45, 46... 

Plant enzyme preparations (ficin, papain, bromelain) are used to tenderize meat. These substances are either sprayed onto the meat cuts or are distributed via the blood vessels of the animal either shortly before or after slaughtering. 

Bromelain has shown a wide variety of pharmacological effects in cliiucal, in vitro and in vivo studies. These effects include bum debridement, anti-inflammatory activity, prevention of epinephrine-induced pulmonary edema, smooth muscle relaxation, stimulation of muscle contractions, enhanced antibiotic absorption, immunomodulation, cancer prevention and remission, antitumor activity, ulcer prevention, sinusitis relief, appetite inhibition, shortening of labor, and enhanced excretion of fat. The precise nature of these effects (some of which are not produced by other proteases such as ficin, papain, and trypsin) is not clear. 

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. 

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. 

Additional examples of type d (Scheme 5.1) bifunctional reactants are provided by the alkaline-earth metal ion complexes of lariat ethers 8-10, bearing a sulfhydryl side arm, instead ofthe phenolic hydroxyl of a calixcrown [23,24]. Here the acyl-receiving and acyl-releasing unit, like in papain and ficin, is a sulfhydryl group. 

In the course of investigations using 4-chloro-7-nitrobenzofurazan as a reactivity probe for identifying the active sites of a number of enzymes such as papain, ficin, and bromelain, the intermediacy of Meisenheimer adducts derived from direct attack of thiolate groups located in the protein has been assumed on the basis of the spectral changes accompanying the process of replacement of the chloro group.232,233... 

Studies of the pH dependence of Vmax //ccat(Eq.9-57) reveal a bell-shaped dependence on pH with pfCa values301 302 of 4 and 9. However, the ion pair is formed at a pH below four with apparent pfCa values of 2.5,2.9, and 3.3 for ficin, caricain, and papain, respectively.302 These low values can be assigned principally to Cys 25 with only very small contributions from His 159 (see Eq. 6-75). A third pKa, perhaps of a nearby carboxylate from Glu 50, affects the rate. For caricain the nearby Asp 158 (Fig. 12-15) has been implicated.303 304... 

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. 

Enzyme Nomenclature. The number of enzymes known exceeds two thousand. A system of classification and nomenclature is required to identify them unambiguously. During the nineteenth century, it was the practice to identify enzymes by adding the suffix -in to the name of their source. Names such as papain, ficin, trypsin, pepsin, etc, are still in use. However, this system does not give any indication of the nature of the reaction catalyzed by the enzyme or the type of substrate involved. 

Stem bromelain has a broad substrate specificity, dose to the specificity of ficin (EC 3.4.22.3), end hydrolyzes a great variety of synthetic and natural substrates. It preferentially cleaves peptide bonds when a hydrophobic group is in the rz position. (According to Scheduler and Betger [32], the amino add residues in a substrate undergoing cleavage are designated as Pi, P2, P3, etc. in the N-tennmal direction and Pi, Y P3r, etc. in the C-temunal direction from the cleaved bond.) Predominantly Gly-Fhe, Phe-Ser, Tyr-Ile, and "iyr-Val bands are cleaved [33,34]. The specificity of bromelain is different from that of papain and ficin in that it hydrolyzes most effectively derivatives of Lys, Ala, T r, Gly, and Asn [35]. 

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. 

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