HUMIN FORMATION DURING WHEAT GLUTEN HYDROLYSIS

1950 ◽  
Vol 28f (7) ◽  
pp. 234-237 ◽  
Author(s):  
C. V. Lusena

The effect of different amounts of starch and crude fat on humin formation during the hydrolysis of gluten prepared from a commercial flour depended on the acid/protein ratio, high ratios giving less humin nitrogen and less humin weight. The nitrogen content of humin was almost independent of the acid/protein ratio but increased with decreasing humin formation. Filtration time increased markedly with increasing purity of the samples. The color of the hydrolyzates varied slightly with impurities and acid/protein ratios.

2014 ◽  
Vol 62 (20) ◽  
pp. 4762-4768 ◽  
Author(s):  
L. Giesler ◽  
D. Linke ◽  
R. G. Berger

2014 ◽  
Vol 1081 ◽  
pp. 110-114 ◽  
Author(s):  
Zhen Zhu ◽  
Hua Yin ◽  
Yan An

This research adopts the pancreatin hydrolysis of silk fibroin active peptide, evaluate the antioxidant activity of hydrolysates. In the process of hydrolysis of silk fibroin, by measuring the amino nitrogen content of neutral formaldehyde titration method. Find the amino nitrogen content gradually stabilized at around 0.37g/L, and superoxide free radical scavenging rate changing with time fluctuation trend, superoxide free radical scavenging rate to a maximum of 65.03% at 220min.The use of silk fibroin hydrolysis process optimization,reaction time 160min, enzyme concentration4% , substrate concentration 20mg/ml, pH 8, temperature 38°C. The hydrolysis process under the hydrolysate on superoxide radical scavenging rate of 72.73%. The scavenging rate of hydroxyl radical is 47.24%. Red blood cell hemolysis induced by H2O2 inhibition rate was 24.30%.


1970 ◽  
Vol 120 (1) ◽  
pp. 15-24 ◽  
Author(s):  
P. S. G. Goldfarb ◽  
R. Rodnight

1. The intrinsic Na+, K+, Mg2+ and Ca2+ contents of a preparation of membrane fragments from ox brain were determined by emission flame photometry. 2. Centrifugal washing of the preparation with imidazole-buffered EDTA solutions decreased the bound Na+ from 90±20 to 24±12, the bound K+ from 27±3 to 7±2, the bound Mg2+ from 20±2 to 3±1 and the bound calcium from 8±1 to <1nmol/mg of protein. 3. The activities of the Na++K++Mg2+-stimulated adenosine triphosphatase and the Na+-dependent reaction forming bound phosphate were compared in the unwashed and washed preparations at an ATP concentration of 2.5μm (ATP/protein ratio 12.5pmol/μg). 4. The Na+-dependent hydrolysis of ATP as well as the plateau concentration of bound phosphate and the rate of dephosphorylation were decreased in the washed preparation. The time-course of formation and decline of bound phosphate was fully restored by the addition of 2.5μm-magnesium chloride and 2μm-potassium chloride. Addition of 2.5μm-magnesium chloride alone fully restored the plateau concentration of bound phosphate, but the rate of dephosphorylation was only slightly increased. Na+-dependent ATP hydrolysis was partly restored with 2.5μm-magnesium chloride; addition of K+ in the range 2–10μm-potassium chloride then further restored hydrolysis but not to the control rate. 5. Pretreatment of the washed preparation at 0°C with 0.5nmol of K+/mg of protein so that the final added K+ in the reaction mixture was 0.1μm restored the Na+-dependent hydrolysis of ATP and the time-course of the reaction forming bound phosphate. 6. The binding of [42K]potassium chloride by the washed membrane preparation was examined. Binding in a solution containing 10nmol of K+/mg of protein was linear over a period of 20min and was inhibited by Na+. Half-maximal inhibition of 42K+-binding required a 100-fold excess of sodium chloride. 7. It was concluded (a) that a significant fraction of the apparent Na+-dependent hydrolysis of ATP observed in the unwashed preparation is due to activation by bound K+ and Mg2+ of the Na++K++Mg2+-stimulated adenosine triphosphatase system and (b) that the enzyme system is able to bind K+ from a solution of 0.5μm-potassium chloride.


2020 ◽  
Vol 5 (5) ◽  
pp. 332-337
Author(s):  
B. A. Kuts ◽  
◽  
V. G. Kuryata

The article presents a study of changes in the functioning of the source-sink system in the heterotrophic phase of development of horse beans (Vicia faba L.) under the conditions of the artificial combination of external (darkness) factor and internal factor (antigiberelline retardant) during germination. It was found that the action of the drug significantly reduced the length of the epicotyl, root and total seedling. Similarly, the dry matter mass of the seedling organs decreased. The level of using seed spare substances under the influence of retardant decreased, as evidenced by the maximum dry matter of cotyledons in plants of this variant and a decrease in the utilization of reserve substances for root and epicotyl formation during germination. Tebuconazole inhibited the breakdown of starch in the dark. The higher content of sugars in the seeds of scotomorphic plants in comparison with the control is associated with a less intensive outflow for the needs of organogenesis – the formation of root and epicotyl structures. Quantitative changes in nitrogen content in scotomorphic seeds were much smaller than changes in starch content. This indicates that the retardant in the dark inhibits the hydrolysis of the reserve protein of the seed, but the process is started after the hydrolysis of starch. The purpose of the study was to establish the effect of tebuconazole on the processes of germination and redistribution of carbohydrates in seedlings of Vicia faba L. Material and methods. The work was carried out on seedlings of horse beans (Vicia faba L.) of Vivat variety, which is a medium-ripe high-yielding variety with a vegetation period of 100-105 days. The variety is technological, resistant to major diseases, has high resistance to lodging, shedding of beans and their cracking. Results and discussion. The combined effect of darkness and the drug of anti-gibberellin action of tebuconazole were used to regulate the intensity of source-sink relations during the germination of horse bean seeds. The seeds of the experimental variant were soaked for a day in 0.5% solution of the triazole-derived drug tebuconazole. Tebuconazole is a transparent crystalline substance of hazard class 3. The seeds of the control variant were soaked for 24 hours in distilled water and sown in cuvettes with wet sand. The biological replication of the experiments is fivefold. The experiment was performed under the action of light and in dark in order to study the implementation of programs of skoto-and photomorphogenesis. Morpho-biometric parameters (root length, seedling length, dry matter weight of individual organs and the whole plant) were determined on the day of 18 of germination. Determination of nitrogen content was carried out according to Keldal method, starch in the organs of seedlings was performed by iodometric method, to determine the content of total sugar and reducing sugar we used Bertrand method in modification by V. Kosolapov. Conclusion. The combination of exogenous and endogenous factors during seed germination significantly changed the intensity of donor-acceptor relations in horse bean seedlings. Under the action of the drug significantly slowed the growth of seedlings in the dark. There was the decrease in the dry matter of the organs of the seedling in dark and noted lower rates of use of reserve substances for organogenesis during germination


Author(s):  
Ahmad Athamneh ◽  
Justin Barone

Trypsin hydrolysis of wheat gluten produced glutamine-rich short peptides with a tendency to self-assemble into supermolecular structures extrinsic to native wheat gluten. Fourier transform infrared and X-ray diffraction data suggested that the new structures formed resembled that of cross-β amyloid fibrils found in some insect silk and implicated in prion diseases. The superstructures were about 10 μm in diameter with clear right-handed helical configuration and appeared to be bundles of smaller fibrils of about 63 nm in diameter. Results demonstrate the potential for utilizing cheap protein sources and natural mechanisms of protein self-assembly to design advanced nanomaterials that can provide a wide range of structural and chemical functionality.


1970 ◽  
Vol 120 (1) ◽  
pp. 1-13 ◽  
Author(s):  
R. Rodnight

1. The effect of chemical agents on the turnover of the Na+-dependent bound phosphate and the simultaneous Na+-dependent hydrolysis of ATP by a membrane preparation from ox brain was studied at an ATP/protein ratio of 12.5pmol/μg. 2. The agents were added immediately after phosphorylation of the preparation in a medium containing 50mm-sodium chloride and 2.5μm-[γ-32P]ATP. 3. Concentrations of sodium chloride above 150mm, calcium chloride to 20mm and suramin to 1.4mm inhibited both phosphorylation and dephosphorylation and concomitantly slowed ATP hydrolysis. At 125mm-sodium chloride dephosphorylation and hydrolysis were slightly slowed without affecting phosphorylation. 4. Ethanol to 1.6m concentration inhibited dephosphorylation without affecting phosphorylation; the bound phosphate was increased and ATP hydrolysis slowed. 5. Ouabain to 4mm concentration partially inhibited ATP hydrolysis and caused a transient (1–2s) rise in bound phosphate followed by a rapid fall to a lower plateau value, which eventually declined to zero by the time ATP hydrolysis was complete. 6. Of the detergents examined Lubrol W, Triton X-100 and sodium deoxycholate had no significant effect on turnover. Sodium dodecyl sulphate and sodium decyl sulphate to 3.5mm and 20mm respectively completely inhibited turnover and ATP hydrolysis and stabilized the bound phosphate.


1972 ◽  
Vol 23 (6) ◽  
pp. 1059 ◽  
Author(s):  
J Leibholz ◽  
PE Hartmann

The digestion of organic matter, nitrogen, and sulphur was measured in sheep fitted with re-entrant duodenal cannulae. The sheep were given 1.4, about 16, or 30 g of nitrogen per 24 hr from barley roughage with or without a nitrogen supplement of lucerne, wheat gluten, or casein. A further diet supplied 16.1 g of nitrogen per day but consisted of 83 % low-quality roughage compared with 50% in the other diets. The flow of digesta to the duodenum varied from 4.4 to 6.8 1. per 24 hr with dry matter intakes of 480–800 g per 24 hr. The sheep were fed hourly and watered continuously, and there was a more than 10-fold variation in the flow of digesta to the duodenum over 2-hr collection periods. The digestibility of organic matter was lower for the diet supplying 1.4 g of nitrogen per day than for the other diets. Between 77 and 96 % of the apparent digestion of organic matter occurred before the duodenum. In the sheep given 1.4 g of nitrogen per 24 hr, the flow of nitrogen to the duodenum was 4.8 g per 24 hr, while in the sheep given about 16 g of nitrogen daily the flow of nitrogen to the duodenum was 8.4–11.8 g per 24 hr. Only 35 % of the dietary intake of nitrogen reached the duodenum in the sheep given 30 g of nitrogen daily. The sheep given the diet containing 83 % low-quality roughage showed a lower retention of nitrogen than those given the other diets of similar nitrogen content. Between I and 9 % of the flow of nitrogen to the duodenum was in the form of ammonia. The flow of sulphur to the duodenum was between 33 and 55% of the dietary intake, while 72-99% of the apparent digestion of sulphur occurred before the duodenum. The digestibility of dietary sulphate sulphur was greater than that of the sulphur found in lucerne.


2009 ◽  
Vol 50 (2) ◽  
pp. 205-209 ◽  
Author(s):  
Jin-shui Wang ◽  
Zhi-yan Wei ◽  
Lu Li ◽  
Ke Bian ◽  
Mou-ming Zhao

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