Trypsin inhibitor activity

Mustakas et al. (46) evaluated the effects of extruder-processing on nutritional quality, flavor, and stability of the product in an attempt to describe extruder conditions which would be acceptable in all three respects. Urease activity was used as an estimation of trypsin inhibitor activity thus the area between the two urease curves in Figure 2 indicates processing conditions which strike a balance between too much and too little heat treatment, showing optimal nutritional quality. Using the flavor and peroxide value isograms, processing conditions may be chosen such that acceptable flavor and stability may also be achieved. 

The degree of destmction of trypsin inhibitors is influenced by moisture content as well as processing time and temperature. With dry extmders, the highest reduction in trypsin inhibitor activity (TIA) appears to occur at the temperature range of 138°C to 150°C and a process moisture content of 20%. It is almost impossible to achieve these parameters without using steam preconditioning, as water injection directly into the extmder barrel can only be done successfully in very limited... 

Tamarind seeds also contain small amounts of anti-nutritional factors such as tannins, phytic acid, hydrogen cyanide, trypsin inhibitor activity and phytohaemaglutination activity, (5). The presence of tannins and other coloring matter in the testa make the whole seeds unsuitable for direct human consumption. Therefore, the testa has to be separated from the kernels by boiling or roasting. Otherwise, side effects such as depression, constipation and gastrointestinal disorders may result (Anon, 1976, cited in (5)). Bhatta et al. (2001, cited in (5)), have considered that a natural source of tannin from tamarind seed husks can be used to depress gas production in mmen fermentation, particularly in crossbred dairy cows. 

Trypsin inhibitor activity of tamarind is 26 Trypsin Inhibitor Unit mg and exhibits lower inhibitory activity than that of varions edible legrrmes like Cicer arietinum. Lens exculenta, Vigna unguiculata (Al-Bakir et al, 1982, cited in (4)) or soybean (Kanwar et al, 1991, cited in (4)). In an earher stirdy with soybeans (Kanwar et al, 1991, cited in 4)), it was reported that cooking eliminates more than 98% trypsin inhibitor activity. 

Wang and Johnson (2001) reported on test measurement methods that were major indicators of soybean oil quality. These tests included peroxide value, anisidine value, FFA content, phospholipid content, total tocopherol content, oxidative stability index, color, and moisture content. For soybean meal, they reported on urease activity, protein dispersibility index (PDI), rumen bypass or rumen undegradable protein, trypsin inhibitor activity, moisture content, residual oil content, protein content, fiber content, color, amino acid profiles, and protein solubility under alkaline (KOH) conditions. 

Romarheim, O.H. M.A. Aslaksen T. Storebakken A. Krogdahl A. Skrede. Effect of extrusion on trypsin inhibitor activity and nutrient digestibility of diets based on fish meal, soybean meal and white flakes. jArch. Anim. Nutr. 2005, 59, 365—375. 

Fig. 19.4. Effect of atmospheric steaming on trypsin inhibitor activity and protein efficiency ratios of soybean meal fed to rats (Source Rackis, 1974).

Fig. 19.7. Correlation between trypsin inhibitor activity and alkaline (HOH) solubility, PDI, and RUP of soybean meals E-E designates extrusion-expelling and SE designates solvent extraction (Source Wang Johnson, 2001).

Figure 2. Indirect measurement of peanut trypsin inhibitor activity by immuno-electrophoretic analysis.

Trypsin inhibitor activity of four soybean varieties during... 

Time Maturation, Days Period Germination Days at 22° C Trypsin Inhibitor Activity, mg/g, Dry-Basis° ... 

Trypsin inhibitor activity on extracts of ddulled Imnature beans decreased 97-98% after 2.5 min In boiling water, e... 

Effect of maturity on trypsin inhibitor activity and heat inactivation in soybeans ... 

Kumar A, Sharma S (2008) An evaluation of multipurpose oil seed crop for industrial uses (Jatropha curcas L.) a review. Ind Crop Prod 28 1-10 Kumar V, Rani A, Tindwani C, Jain M (2003) Lipoxygenase isozymes and trypsin inhibitor activities in soybean as influenced by growing location. Food Chem 83 79-83 Kunioka M, Kawaguchi Y, Doi Y (1989) Production of biodegradable copolyesters of 3-hydroxy-butyrate and 4-hydroxybutyrate by Alcaligenes eutrophus. Appl Microbiol Biotechnol 30 56-573... 

XII Hageman factor The first factor in the intrinsic pathway. A/, 74000 (bovine), 76000 (human). Single chain glycoprotein. Activated by plasmin, kallikrein and XII,. Inhibited by antithrombin III (inhibition accelerated by heparin). Cl esterase inhibitor and lima bean trypsin inhibitor. Activation of XII initiated by contact with abnormal surfaces. 

Yen, J. T., Hymowitz, T., and Jensen, A. H., 1974, Effects of soybeans of different trypsin-inhibitor activities on performance of growing swine, J. Anim. Sci., 38 304-309. 

Russet Burbank potatoes were quartered and placed in a water bath at 80 C for 10 min. The tubers were rinsed with cold water and blended to a paste. Absolute ethanol was blended in slowly with the paste until it was 80% ethanol by volume. The mixture was filtered through Whatman No. 1 filter paper with the aid of a vacuum. The ethanol in the filtrate was removed by vacuum evaporation and the resulting solution was dialyzed in a 2,000 MW cut off dialysis bag against several changes of distilled water. The remaining extract in the dialysis bag was lyophilized. The dry material contained one major polypeptide, CPI, and some minor components. On a protein basis the material was over 95% CPI. Purity of this crude CPI fraction was also demonstrated by electrophoresis by the method of Panyim and Chalkley (8). No Inhibitor I nor Inhibitor II could be detected by immunological techniques, however a small quantity of trypsin inhibitor activity (less than 0.5%) was present, presumably from contamination by the polypeptide trypsin inhibitor that is present in potato tubers (4). This CPI preparation was utilized for the chick feeding experiments. 

Perez-Maldonado, R.A., Mannion, P.W., FarreU, D.J. and James, A.T. (1999), Raw Soybeans Selected for Low Trypsin Inhibitor Activity for Poultry Diets, Cleveland, Australia Rural Industries Research Development Corporation, www.rirdc.gov.au/ reports, accessed 28 August 2004. 

With soybean Bowman-Birk proteinase inhibitor, Odani and Ikenaka (1973) succeeded in separating two small fragments, one with 38 amino acids residues having a trypsin inhibitor activity, the other with 29 residues having a chymotrypsin inhibitor activity. However, reconstitution was not achieved. 

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