Salt-soluble Protein Fraction Research Articles

Study of macronutrients in hemp seeds during short-term germination

At present, hemp seeds are becoming increasingly popular as a source of nutrients. This work addressed the dynamics of macronutrients in the process of short-term germination of hempseeds by chemical and spectroscopic methods. Lyudmila 2021 cultivated hemp seeds along with hemp sprouts were used as objects of research. The germination of hemp seeds was carried out under laboratory conditions using special trays at 18–20 °C with the water added at a ratio of 2:1 for 5 days with periodic moistening. The obtained experimental data on the protein complex suggested that, in the studied interval of the germination of hemp seeds, the key hydrolytic decomposition of proteins occurs along with changes in structural components, including through the synthesis of new proteins accompanying the sprouting. The variations in such parameters as fat content, acid number and peak intensity of functional groups in the lipid fingerprint region (1745, 1157 and 1140 cm-1) indicated the accumulation of fatty acids as a result of the hydrolysis of triglycerides. The analysis of the IR spectra of hemp sprouts and the intensity of the bands of the corresponding functional groups in the carbohydrate region (1200–680 cm-1) suggested the intensive hydrolytic decomposition of polysaccharides. The variation in the content of extractive matter in the aqueous solutions of hemp sprouts indicated the accumulation and utilisation of water-soluble substances at the early stages of germination. The data on the predominance of water- and salt-soluble protein fractions indicated an increase in the biological value of hemp seeds during short-term germination.

The study of biochemical properties of legume flour (peas, soybeans), physical and baking indicators of the dough from mixtures with wheat flour

High protein content, simplicity and time of cooking are two main advantages with which legumes have gained popularity among the population, however, this culture is used not only in its pure form, but also in the form of additives for baking. Adding pea and soybean flour to composite mixtures affects the behavior of the dough, requires corrections in the baking process, and all these issues can be resolved by farinographic analysis. The purpose of the current study was to determine the biochemical parameters of whole-meal pea and soybean flour, to study the rheological properties of the dough of composite mixtures with grain legume flour and to evaluate the efficiency of mixing pea and soybean flour with premium wheat flour according to the results of baking assessment. There has been identified nutritional value of whole-meal pea and soybean flour, additives exceeding the protein content on 13.2–23.6%, oil content on 1.3–21.2%, sugar content on 3.2–9.3%, which is very important in baking. There has been characterized the influence of the type of ingredients (pea, soybean flour) on the rheological properties of dough using farinographic analysis, when 5% addition of pea flour (the variety ‘Flagman 9’) to composite mixtures did not worsen the physical traits of the dough, 10 and 15% addition reduced dough stability on 1–2 minutes, valorimetric assessment on 4–6 e.u., but water absorption capacity of flour raised on 6% in relation to wheat flour. The addition of whole-meal soybeans (the variety ‘Samer 1’) strengthened and improved the physical the dough parameters, however, the volume of bread reduced because of a decrease in gluten percentage in the mixtures and the prevailing salt-soluble (globulins) and water-soluble (albumin) protein fractions. There has been estimated the efficiency of mixtures of premium wheat flour with wholemeal pea and soybean flour, when the overall baking assessment gave positive results of 4.0–4.6 points; in that case the bread is attractive, of regular shape, with smooth crust without cracks, the crumb color is light yellowish with fine porosity, but a little denser than in control, the smell is pleasant and fragrant.

Comparison of the Nutritional Composition of Bullfrog Meat from Different Parts of the Animal.

The objective of this study was to evaluate the nutritional content of bullfrog meat from different parts of the animal, including fore-chest, thigh and calf. Bullfrog meat was found to be a rich source of proteins, essential amino acids and minerals, but with a low fat content, compared with other aquatic meat products. There was no significant difference (p>0.05) between thigh and calf in mineral content (K, P, Na, Mg, Ca, Zn, Fe, Cu, and Mn), but the contents of K, P, and Mg were higher in thigh and calf than in the fore-chest (p<0.05). The salt-soluble, water-soluble and insoluble protein bands in sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) electrophoresis, from fore-chest, thigh and calf were similar, with the most abundant bands being 35 kDa (salt-soluble protein), 35–48 kDa (water-soluble protein) and 48 kDa (insoluble protein). The results showed that the insoluble protein content in the fore-chest meat was higher than that in the thigh meat and calf meat, but the salt-soluble protein fraction was the most abundant in thigh meat. These results showed that the nutrients in different parts of bullfrog meat were different.

Short-term capture-based aquaculture of Atlantic cod (Gadus morhua L.) generates good physicochemical properties and high sensory quality during frozen storage

The annual global catch of Atlantic cod (Gadus morhua L.) is above 1,000,000 tons, and a large proportion is preserved and sold as frozen products. In Greenland, a new innovative fishing method centred on capture-based aquaculture has been developed. To compare the new fishing and processing method with the conventional method, the texture, colour, water holding capacity, salt soluble proteins and sensory properties of fillets were evaluated during 12 months of frozen storage. High quality life (HQL) and practical storage life (PSL) were determined for each fishing and processing method based on sensory evaluation, and by using water holding capacity and the salt soluble protein fraction as indices of quality. Capture-based aquaculture fishing and related processing increased frozen storage durability regarding texture attributes, blood content and sensory properties compared to the conventional method. Lowering the storage temperature to −40 °C increase the HQL to >12 months compared to a HQL of 4–6 months at −20 °C.

Expression of α-amylase inhibitors in diploid Triticum species

The aim of the work was to characterize the expression of various α-amylase inhibitors (αAIs), well known anti-nutritional compounds, for the development of healthier diploid wheat-based functional foods.The salt-soluble protein fractions from the seeds of 53 accessions among Triticum monococcum subsp. monococcum (T.m.), T. monococcum subsp. boeoticum (T.b.) and Triticum urartu (T.u.) were analyzed by immunoblotting after SDS–PAGE and Urea–PAGE using polyclonal antibodies (PABs) raised against 0.19 and 0.28 αAIs expressed in bread-wheat. Reverse zymography with human saliva and Tenebrio molitor α-amylases was used to assay inhibition activity. A great variability of the expression of αAI-related proteins was observed among T.b. and T.u. PABs, and reverse zymography revealed different bands, often not correlating with those present in bread-wheat. Two-dimensional electrophoresis followed by immunoblotting and mass spectrometric analysis identified these proteins as αAIs. Interestingly, no signal was observed within T.m. accessions. This makes T.m. an important candidate for the production of novel functional foods.

Influence of cooking process on protein fractions in cooked ham and mortadella

The mortadella is a pork meat sausage (in natural or artificial bowel) accurately triturated and mixed with little backfat cubes, salt, sodium nitrate and nitrite, spices and peppercorns, and then cooked in oven for many hours. The cooked ham is obtained from an anatomically completed piece of meat; the working process provides the addiction of salt and spices, the brine, the bones removal, the churning and the pressing, so the cured meat is first packed in a mould provided for this purpose, then cooked and after cooled and packed. The meat cooking is the last step in the cooked sausage production technology, and let us obtain a stable and eatable product. The effect of the heat and the lenght of processing are the main responsibles for modifications in water- and salt-soluble protein fractions. Indeed myofibrils denature themselves after cooking and consequently their solubility decreases; particularly the denaturation begins over 30°C in the myosin chain, instead the actin solubility begins to decrease over 60°C, being the actin more stable than myosin (Barbieri et al., 1997)...

Capillary electrophoresis for bovine and ostrich meat characterisation

The objective of this study was to characterise, compare and quantify the water soluble protein (WSP) and salt soluble protein (SSP) fractions from bovine and ostrich muscle by using sodium dodecyl sulphate polymer-filled capillary gel electrophoresis (CE-SDS). Samples were raw ostrich leg and eye round beef collected 24 and 48 h, respectively, after sacrifice from local slaughter houses. WSP were extracted with cold double distilled deionized water and SSP with 0.6 M NaCl/0.01 M phosphate buffer pH 6 with 0.5% polyphosphates. Separation of WSP and SSP extracts was achieved by CE-SDS. Quantitative data for individual proteins was generated by constructing a calibration curve using bovine serum albumin (BSA) as a standard. The WSP profiles showed differences for bovine and ostrich meat, both qualitatively and quantitatively and could be employed for species differentiation. Quantitative data derived for WSP and SSP from bovine and ostrich muscle showed significant differences among individual proteins. A comparison of protein profiles form ostrich and bovine meat should be useful for meat species differentiation and muscle characterisation for establishing relations to meat quality.

Use of the enzyme transglutaminase for developing glutenfree noodle products from pea flour

Yellow pea flour contains very low quantity of prolamins, thus it could be a good alternative dietary source for individuals suffering from celiac disease or wheat allergy. Beside emulsifiers, enzymes can be used for developing noodle structure with high quality. Transglutaminase (TG) enzyme was tested in model systems for improving noodle structure by using beneficial cross-linking property of the enzyme. Sensory-and cooking properties and biochemical attributes of proteins were evaluated to characterize structure-function relationships in accordance with the concentration of the applied enzyme. The amount of water and salt soluble protein fractions was reduced meaningfully and the molecular weight distributions assessed by SDS PAGE were changed by addition of 50–200 mg kg −1 TG enzyme. At the same time, sensory properties were improved and high water uptake and low cooking loss were also observed. Forasmuch an increase has been expected in the amount of the cross-linked molecules, the cross-reactivity o...

Proteolysis in Model Sourdough Fermentations

Model wheat doughs started with six different lactic acid bacteria (LAB), with or without a commercial baker's yeast culture, were used to study proteolysis in sourdough fermentations. Cell counts, pH, and free amino acid concentration were measured. Sequential extraction of dough samples was performed to separate wheat proteins. The salt-soluble protein fraction (albumins and globulins) was analyzed by RP-HPLC and SDS-PAGE, whereas propanol-soluble (gliadins) and insoluble (glutenins) protein fractions were analyzed by SDS-PAGE only. Multivariate statistical methods were used for the analysis of results. The presence of yeasts and LAB affected RP-HPLC and SDS-PAGE patterns of the salt-soluble fraction in a complex way. The only changes in the gluten proteins that could be related to the presence of LAB were the appearance of new protein fragments (20 and 27 kDa) from gliadins and the degradation of high molecular weight glutenin subunits.

Physicochemical, functional and microbiological quality of buffalo liver

Buffalo liver is an important edible meat byproduct. However, in developing countries including India, it has a low commercial value and is underutilized. The present investigation was conducted to provide basic information on physicochemical, functional and microbiological quality of buffalo liver. Proximate composition was: moisture – 71.92%, protein – 18.44%, fat – 5.60%, carbohydrate – 2.72%, total ash – 1.32% and total energy – 135 kcal. Mineral concentrations (mg%) in liver were: Na – 60.04, K – 274, Ca – 5.60, Mg – 6.20, Fe – 20.86 and Cu – 5.60. Mean glycogen (mg/g), total liver pigments (mg/g) and cholesterol (mg%) were 7.07,8.49 and 283.88, respectively. The mean pH values of buffalo liver was 6.42, WHC – 38 ml per 100 g and cooking yield was 73.15%. Protein extractability studies indicated that liver contains higher amounts of water-soluble proteins (20–40%) than salt soluble proteins (7–15%) and presence of high molecular weight proteins in salt soluble protein fractions. The average microbial counts (log 10 cfu/g) for different organisms were APC – 6.10; psychrotrophs – 4.30; enterobacteriaceae counts – 4.97; staphylococcal counts 2.50 and total coliforms – 2.82.

Identification of Allergen Fractions of Wheat Flour Responsible for Anaphylactic Reactions to Wheat Products in Infants and Young Children

Wheat is a food allergen which occasionally causes anaphylactic reactions exclusively in young children. There is very little knowledge of the clinical outcome in cases of food-related anaphylaxis and the differences in the allergenic protein components of food involved, comparing individuals who have suffered from an anaphylactic reaction with other individuals. The objectives of the present study were to examine the clinical features of 7 young children who had experienced anaphylactic reactions after ingesting wheat flour-containing products, and to analyze the allergens in wheat flour responsible for the anaphylactic symptoms. We measured the total IgE levels and the levels of IgE antibodies specific to wheat flour and performed IgE immunoblotting, comparing the sera from these children with sera from patients with atopic dermatitis. All sera from children who had experienced anaphylactic reactions were found to be positive for IgE specific to wheat. IgE immunoblotting revealed that 3 of these 7 children had sera showing reactivity to components of the salt-soluble protein fraction (16, 35–67 and 94 kD) and salt-insoluble protein-containing fraction (16, 38 and 70 kD) and 4 had no sera showing reactivity to components of the salt-soluble fraction. Patients with atopic dermatitis showed similar staining patterns. Various proteins in wheat flour could be allergens responsible for anaphylaxis and atopic dermatitis in infants or young children. Our findings suggest that these two clinically diverse allergic diseases do not necessarily represent responses to different allergenic proteins of wheat.

Variation of Storage Proteins and Isozymes within Maize Inbred Lines

Seed storage proteins of ten maize inbred lines were investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis. In addition, fourteen isozyme loci representing nine isozyme systems were analysed. Salt-soluble protein fraction contained a large number of proteins (30 - 40 bands) of different sizes with genotypic differences among the ten inbred lines. The methionine-rich 10 kD zein showed differential expression in the ten inbred lines with different migration rates on the SDS-PAGE. This polypeptide was completely absent in the inbred line G221D. Among nine of the inbred lines, eight of 14 isozyme loci were polymorphic and six were monomorphic resulting in seven unique fingerprints.

Iron solubilisation by chicken muscle protein digests

The objective of this work was to compare the solubilisation of iron by in vitro digests of soluble and insoluble protein fractions from chicken muscle. Chicken breast muscle was extracted to provide dilute salt-soluble protein (DSSP) and dilute salt-insoluble protein (DSIP) fractions. These fractions together with casein and ovalbumin were subjected to in vitro digestion in the presence of ferric iron. After proteolytic digestion, soluble iron increased fourfold for DSSP, 20-fold for DSIP, twofold for casein and 0.5-fold for ovalbumin. 64% of the soluble iron in the DSSP digest and 30% of the soluble iron in the DSIP digest were ferrous; in the casein and ovalbumin digests, less than 6% was ferrous. Dialysable iron was less than 5% of the soluble iron for all proteins and was mostly ferric iron. DSIP solubilised twice as much iron as DSSP but much less than casein or ovalbumin digests. It was concluded that muscle proteins solubilise iron by reduction and chelation to mostly large (non-dialysable) peptides resulting from digestion.

Changes in flax ( Linum usitatissmum) seed nitrogenous compounds during germination

The changes in the nitrogenous compounds of flaxseed during an 8-day germination period were studied. The dry matter content of the seeds was reduced by 35% at the end of the germination. During the germination period, a relatively small decrease was observed in total nitrogen content, but there was an increase in the content of non-protein nitrogen from 9 to 33.5% of the total amount. An increase in the total content of free amino acids was also observed. Among individual amino acids, glutamine showed a marked change during the germination period indicating that it is the favoured amide donor in the developing flax seedlings. An increase in the water-soluble protein and a decrease in the salt-soluble protein fractions was also observed. The content of polyamines, namely agmatine, spermidine and putrescine, which are important in controlling cellular metabolism and growth, was also increased during the germination period. After day 8 of germination, the contents of cyanogenic glycosides, linustatin and neolinustatin in the seeds were reduced by 40 and 70%, respectively. Trypsin inhibitor content was very low in flaxseed and only trace amounts were present after 8 days of germination.

Taxonomic evaluations of the genusPinus (Pinaceae) based on electrophoretic data of salt soluble and insoluble seed storage proteins

Electrophoretic studies on seed storage proteins of various gymnosperm species showed that both salt soluble and insoluble protein fractions give taxonomic information. Among species of the genusPinus evident differences are found between the subgeneraHaploxylon (Strobus) andDiploxylon (Pinus). In sect.Strobus the two subsectt.Strobi andCembrae are readily distinguished fromP. bungeana (sect.Parrya) which appears to fall in an intermediate position between haploxyl and diploxyl pines. Among the species of subg.Diploxylon, “mountain pines” show very similar protein patterns in agreement with their recent speciation (Quaternary).

Glutamine enhances storage protein synthesis in Medicago sativa L. somatic embryos

The vigor of seedlings from dry somatic embryos is considerably less than the vigor of seedlings from seeds, perhaps due to the low levels of storage proteins and low levels or different species of carbohydrates deposited in the dry somatic embryos. The effects of sucrose, abscisic acid and glutamine applied during maturation on the accumulation of storage proteins in the dry somatic embryos of Medicago sativa L. were investigated in an attempt to improve vigor. A cell suspension containing 2,4-dichlorophenoxyacetic acid (2,4-D) was sieved and the somatic embryos were developed to the torpedo stage on hormone-free BOi2y medium for 7 days. For experimentation, embryo maturation was divided into two phases of 10 days duration each: phae II and phase II maturation. The components of the cell culture medium were varied during the first 10-day period of maturation (phase I). This was followed by phase II maturation on standard BOi2y medium with 20 μM abscisic acid (ABA) to induce desiccation tolerance. Fully matured and air-dried somatic embryos were sampled for analysis. Increasing sucrose from 30 to 50 g l −1 and adding a 50-mM glutamine supplement to the phase I maturation medium increased somatic embryo dry weight from 1.5 to 2.5 mg. Sucrose did not have a significant effect on synthesis of either the low salt soluble (S-1) protein fraction containing water soluble enzymatic proteins, high and low molecular weight and alfin (7S) storage proteins, or the high salt soluble (S-2) fraction proteins containing mainly medicagin (11S) storage proteins. The presence of 2 μM ABA depressed total protein accumulation, whereas 50 mM glutamine increased the synthesis of the S-2 relative to S-1 proteins. In the presence of 50 mM glutamine the quantity of high salt soluble S-2 proteins, consisting of mainly medicagin (11S) storage proteins, increased 2-fold in somatic embryos. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that glutamine increased the polypeptides of the storage proteins, especially medicagin (11S). This enhancement may represent improved nutrition of the somatic embryo or enhanced transcription or translation of the storage protein genes.

Endosperm protein accumulation in wild and cultivated barley and their cross grown in spike culture

The high protein wild relatives of cultivated cereals have proven difficult to utilize in plant breeding by direct selection for high grain protein percentage, and hence alternative selection criteria are needed. In this study, a spike culture method was used to measure differences in protein accumulation between wild and cultivated barley, and their cross, at different levels of nitrogen supply. Three genotypes, barley cultivar Hordeum vulgare L. cv. Clipper, a wild barley accession H. spontaneum Koch line 363, and a high protein F5 line (38.4) derived from their cross, were grown from 8 to 27 days after flowering in in vitro spike culture. Nitrogen supply in the culture medium was either 0.4 g/l or 2.0 g/l of N supplied as NH4NO3. Spikes were harvested at approximately 3 day intervals during grain development, and salt soluble and hordein protein fractions were measured. Lines 363 and 38.4 differed from ‘Clipper’ in having extremely high initial rates of protein accumulation, even at 0.4 g/l N. In high nitrogen conditions all three genotypes reached similar salt soluble plus hordein protein levels. Hordein-1 and hordein-2 fractions were measured separately; the percent of hordein-1 was higher in lines 363 and 38.4 than in ‘Clipper’ at 0.4 g/l N. For all parameters measured, pot-grown spikes of matching age were harvested and were shown to be similar to the 0.4 g/l N treatment. The possible utilization of spike culture for identification of critical protein accumulation parameters is discussed, in relation to their possible utilization in breeding.

Electrophoretic characterization of rice varieties using single seed (salt soluble) proteins

Variation of salt soluble protein fractions of seeds has been observed in a number of rice varieties as recorded in their electrophoregram tracings: both qualitative and quantitative differences were present. Analysis of variance has been found to be useful in estimating the quantitative differences. These tracings or patterns appear to be unique for each of the varieties investigated and seem to be genetical in nature as they remain constant under different environmental conditions, and therefore could be conveniently used for variety identification.

SOY AND MEAT PROTEINS AS FOOD EMULSION STABILISERS. 3. THE INFLUENCE OF SOY AND MEAT PROTEIN FRACTIONS ON OIL-WATER INTERFACIAL TENSION.

Abstract Interfacial tension measurements at an oil-water interface determined as a function of pH and NaCl indicate that the adsorption of 7S, IIS and acid precipitated (APSP) soy protein fractions, and water (WSMP) and salt soluble (SSMP) meat protein fractions, are time dependent and are greatly influenced by molecular configuration. The interfacial tension decreases more rapidly, and its equilibrium value is lower, with increasing compactness of the molecules. The nonglobular SSMP fraction exhibited the fastest rate of interfacial tension reduction and the lowest equilibrium value, with WSMP next in order. Soy protein fractions were less effective, with the 7S fraction exerting a greater influence than the IIS fraction or APSP.

SOY AND MEAT PROTEINS AS FOOD EMULSION STABILIZERS 1. VISCOELASTIC PROPERTIES OF CORN OIL‐IN‐WATER EMULSIONS INCORPORATING SOY OR MEAT PROTEINS

The creep compliance‐time response of 50% (wt/wt) corn oil‐in‐water emulsions has been studied at a constant stress of 47.8 dyne cm−2 over the pH range 2.5–7.5. The emulsions were stabilised by acid precipitated (APSP), 7S(7SPRF) or 11S(11SPRF) soy protein fractions, water soluble (WSMP) or salt soluble (SSMP) meat protein fractions. All the emulsions exhibited viscoelasticity. WSMP emulsions exhibited the highest initial viscoelasticity parameter values and this was attributed to the strong interlinking of WSMP loops adsorbed on the surfaces of adjacent oil drops. The parameter values of all the emulsions increased during the first 5–7 days storage and then they decreased. At any selected pH the 7SPRF emulsions exhibited the largest relative increase in parameter values. The changes in viscoelasticity during storage were explained on the basis of the relative effects of further protein loop interlinkage and drop coalescence.