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Trypsin Inhibitor Activity (trypsin + inhibitor_activity)
Selected AbstractsVegetative Storage Protein with Trypsin Inhibitor Activity Occurs in Sapindus mukorassi, a Sapindaceae Deciduous TreeJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 4 2009Shi-Biao Liu Abstract A vegetative storage protein (VSP) with trypsin inhibitor activity in a deciduous tree, Sapindus mukorassi, was characterized by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western-blot, immuno-histochemical localization, light- and electro-microscopy, together with analysis of proteinase inhibitor activity of the purified VSP in vitro. There were two proteins with molecular masses of about 23 and 27 kDa in a relatively high content in the bark tissues of terminal branches of S. mukorassi in leafless periods. The proteins decreased markedly during young shoot development, indicating their role in seasonal nitrogen storage. Immuno-histochemical localization with the polyclonal antibodies raised against the 23 kDa protein demonstrated that the 23 kDa protein was the major component of protein inclusions in protein-storing cells. The protein inclusions were identified by protein-specific staining and should correspond to the electron-dense materials in different forms in the vacuoles of phloem parenchyma cells and phloem ray parenchyma cells under an electron microscope. So, the 23 kDa protein was a typical VSP in S. mukorassi. The 23 and 27 kDa proteins shared no immuno-relatedness, whereas the 23 kDa protein was immuno-related with the 22 kDa VSP in lychee and possessed trypsin inhibitor activity. The 23 kDa protein may confer dual functions: nitrogen storage and defense. [source] Quality attributes of vegetable soybean as a function of boiling time and conditionINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2009Leandro A. Mozzoni Summary Vegetable soybeans are marketed fresh or frozen, either shelled or in pods. The objective of this research was to characterise the change in quality attributes of vegetable soybean with boiling time (0,20 min), and presence/absence of pods, using an electrical-resistance stove or a steam-jacketed kettle. Trypsin inhibitor activity (TIA), texture, colour, soluble sugars, nitrogen, calcium and iron content were analysed. Blanching using a steam-jacketed kettle for approximately 2 min rendered 80% inactivation of TIA, and resulted in high colour, texture and sucrose. There were no differences between blanching in pods or shelled for TIA, colour and texture; however, blanching in pods prevented losses of sucrose. Blanching did not affect iron, mono- and oligosaccharide levels, but increased nitrogen and calcium content. Additionally, we observed that all traits decreased linearly with cooking time when using an electrical-resistance stove, except for calcium and nitrogen that increased, and oligosaccharides that remained constant. [source] Quality Characteristics of Spaghetti as Affected by Green and Yellow Pea, Lentil, and Chickpea FloursJOURNAL OF FOOD SCIENCE, Issue 6 2005Yonghuan H. Zhao ABSTRACT Spaghetti was made from semolina, containing 5% to 30% milled flours of green pea, yellow pea, chickpea, and lentil, respectively. Physical-chemical characteristics and descriptive sensory and consumer acceptance characteristics were measured. Spaghetti containing legume flours darkened the spaghetti (P < 0.05) but did not affect the cooked weight significantly. Cooking loss and firmness increased with an increase in legume flour content. Trypsin inhibitor activity (TIA/g) was significantly reduced after cooking. Descriptive intensity analysis showed that the firmness, pulse flavor, and color intensity of the pasta products increased with the increase in the percentages of legume flour fortification up to 30%, whereas the intensity of the shiny appearance, elasticity, and overall quality decreased. Consumers preferred control spaghetti (without legume additives) more than the spaghetti containing legume flours and they slightly liked the spaghetti with 15% lentil or green pea and the spaghetti with 20% chickpea or yellow pea. [source] Changes in the biochemical and functional properties of the extruded hard-to-cook cowpea (Vigna unguiculata L. Walp)INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2010Karla A. Batista Summary Changes in the biochemical and functional properties of the hard-to-cook cowpea bean after treatment by the extrusion process are reported. The extrusion was carried out at 150 °C, with a compression ratio screw of 3:1, a 5-mm die, and a screw speed of 150 r.p.m. The extrusion caused the complete inactivation of the ,-amylase and lectin and it also reduced the trypsin inhibitor activity (38.2%) and phytic acid content (33.2%). The functional properties were also modified by the process, an increase of 2.5 times in the water absorption index and 3.1% in the water solubility were observed. The digestibility of the hard-to-cook flour of the cowpea bean was improved after the extrusion, with a 55.9% increase in protein digestibility and a 5.9% increase in starch digestibility. [source] Vegetative Storage Protein with Trypsin Inhibitor Activity Occurs in Sapindus mukorassi, a Sapindaceae Deciduous TreeJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 4 2009Shi-Biao Liu Abstract A vegetative storage protein (VSP) with trypsin inhibitor activity in a deciduous tree, Sapindus mukorassi, was characterized by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Western-blot, immuno-histochemical localization, light- and electro-microscopy, together with analysis of proteinase inhibitor activity of the purified VSP in vitro. There were two proteins with molecular masses of about 23 and 27 kDa in a relatively high content in the bark tissues of terminal branches of S. mukorassi in leafless periods. The proteins decreased markedly during young shoot development, indicating their role in seasonal nitrogen storage. Immuno-histochemical localization with the polyclonal antibodies raised against the 23 kDa protein demonstrated that the 23 kDa protein was the major component of protein inclusions in protein-storing cells. The protein inclusions were identified by protein-specific staining and should correspond to the electron-dense materials in different forms in the vacuoles of phloem parenchyma cells and phloem ray parenchyma cells under an electron microscope. So, the 23 kDa protein was a typical VSP in S. mukorassi. The 23 and 27 kDa proteins shared no immuno-relatedness, whereas the 23 kDa protein was immuno-related with the 22 kDa VSP in lychee and possessed trypsin inhibitor activity. The 23 kDa protein may confer dual functions: nitrogen storage and defense. [source] Defense mechanisms against grazing: a study of trypsin inhibitor responses to simulated grazing in the sedge Carex bigelowiiOIKOS, Issue 9 2007Åsa Lindgren Trypsin inhibitors have been suggested to constitute an inducible defense in the sedge Carex bigelowii, and some former studies suggest that this might be a cause for the cyclic population dynamics in many alpine and arctic small mammals, for example lemmings (Lemmus lemmus). We investigated this further by using a method of simulated grazing (clipping) at different intensities, in three different habitats with varying resource availability, with different harvest times (hours after clipping), and two different stages of ramets (reproductive/vegetative) in a study from the Swedish mountain range. Our results do not indicate that C. bigelowii has an inducible defense constituted by an increase in trypsin inhibitor activity (TIA), but rather that the amount of soluble plant proteins (SPP) is lowered in wounded plants. The responses were somewhat different in the three habitats, with ramets growing in the marsh showing the highest ratio of TIA to SPP, due to low amounts of SPP. We did not find any significant effects of harvest time, or of the stage of the ramet that could support the hypothesis of an inducible defense. To conclude, we could not find any evidence for an inducible defense consisting of trypsin inhibitors in Carex bigelowii ramets, but we did find variations in the amount of SPP that may have nutritional consequences for herbivores. [source] | |||||||||||||