SOME ASPECTS OF THE ENZYMIC HYDROLYSIS OF URINARY 17-KETOSTEROID CONJUGATES

1960 ◽  
Vol 38 (7) ◽  
pp. 769-776 ◽  
Author(s):  
R. Hobkirk ◽  
J. J. Cohen
Keyword(s):  
Liver Enzymes ◽  
Striking Difference ◽  
Degree Of Hydrolysis ◽  
Enzyme Preparations ◽  
Bacterial Preparation ◽  
Bacterial Enzyme ◽  
The Difference ◽  
Normal Urine ◽  
High Degree ◽  
Hydrolysis Of

Four enzyme preparations containing β-glucuronidase, of bacterial, mammalian, and molluscan origin, have been shown to be equally effective in liberating 17-ketosteroids (17-KS) of the 5β-(etiocholane) configuration in normal urine. The bacterial preparation releases steroids of the 5α-(androstane) configuration more rapidly than do the molluscan enzymes and with much greater ease than does the liver enzyme. In view of the data obtained it seems unlikely that the striking difference between the bacterial and liver enzymes can be due to the hydrolysis of some labile conjugate, such as sulphate, by the former and not by the latter. Possibilities that the difference is due to the hydrolysis of an unknown type of urinary conjugate by the bacterial preparation, or to the low specificity of the bacterial β-glucuronidase, are discussed. The high degree of hydrolysis of 17-KS conjugates by the bacterial enzyme followed by solvolysis suggests this as a most useful hydrolytic procedure.

SOME ASPECTS OF THE ENZYMIC HYDROLYSIS OF URINARY 17-KETOSTEROID CONJUGATES

1960 ◽  
Vol 38 (1) ◽  
pp. 769-776
Author(s):  
R. Hobkirk ◽  
J. J. Cohen
Keyword(s):  
Liver Enzymes ◽  
Striking Difference ◽  
Degree Of Hydrolysis ◽  
Enzyme Preparations ◽  
Bacterial Preparation ◽  
Bacterial Enzyme ◽  
The Difference ◽  
Normal Urine ◽  
High Degree ◽  
Hydrolysis Of

Four enzyme preparations containing β-glucuronidase, of bacterial, mammalian, and molluscan origin, have been shown to be equally effective in liberating 17-ketosteroids (17-KS) of the 5β-(etiocholane) configuration in normal urine. The bacterial preparation releases steroids of the 5α-(androstane) configuration more rapidly than do the molluscan enzymes and with much greater ease than does the liver enzyme. In view of the data obtained it seems unlikely that the striking difference between the bacterial and liver enzymes can be due to the hydrolysis of some labile conjugate, such as sulphate, by the former and not by the latter. Possibilities that the difference is due to the hydrolysis of an unknown type of urinary conjugate by the bacterial preparation, or to the low specificity of the bacterial β-glucuronidase, are discussed. The high degree of hydrolysis of 17-KS conjugates by the bacterial enzyme followed by solvolysis suggests this as a most useful hydrolytic procedure.

scholarly journals Effect of agitation on the efficiency of enzymatic hydrolysis of highly concentrated media of extruded corn starch

2020 ◽  
Vol 82 (3) ◽  
pp. 96-103
Author(s):  
A. Y. Sharikov ◽  
V. V. Ivanov ◽  
M. V. Amelyakina
Keyword(s):  
Dynamic Viscosity ◽  
Corn Starch ◽  
Degree Of Hydrolysis ◽  
Screw Extruder ◽  
Enzyme Preparations ◽  
Continuous Mixing ◽  
Dextrose Equivalent ◽  
Twin Screw ◽  
High Degree ◽  
Hydrolysis Of

The influence of the mixing factor and its intensity was investigated at the stage of developing a technology for processing highly concentrated hydrolysates (50% solids) of extruded corn starch. The starch was extruded using a twin-screw extruder at a temperature of 185 °C and a pressure at the die of 2 MPa. Extruded substrate was hydrolyzed with enzyme preparations of ?-amylase and glucoamylase for 4 hours with different stirring modes. The significance of the stirring speed on the degree of hydrolysis of extruded starch, especially in the first 2 hours of enzymatic treatment, has been established. As a result of 4-hour exposure, the dextrose equivalent of the hydrolyzate incubated without stirring was 52.2. Dextrose equivalent of the hydrolysates stirred at speed of 100, 200 and 500 rpm was 54.5, 59.3, and 59.8, respectively. The study of rheological properties showed that the dynamic viscosity of a medium without stirring significantly differed from the viscosity of a medium with stirring throughout the entire hydrolysis period. As a result, the dynamic viscosity of the sample without stirring and with stirring decreased from 3 Pa?s to 0.35 Pa?s and from 2.5-2.8 Pa?s to 0.145-0.221 Pa?s, respectively. An double increase of the glucoamylase dosage made the mixing factor after 4 hours of hydrolysis insignificant and increased the dextrose equivalent value by 18-35%. The dextrose equivalents of samples without stirring and with stirring at a frequency of 200 rpm were 70 and 71, respectively. But in the first 2 hours of hydrolysis, the stirring factor for samples with an increased dosage of glucoamylase was also statistically significant. The study showed that hydrolysis of highly concentrated media of extruded starch under the condition of high-quality homogenization with the enzymes provides a high degree of bioconversion without the requirement for continuous mixing,

scholarly journals Coal Fly Ash Ceramics: Preparation, Characterization, and Use in the Hydrolysis of Sucrose

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Ricardo Pires dos Santos ◽  
Jorge Martins ◽  
Carlos Gadelha ◽  
Benildo Cavada ◽  
Alessandro Victor Albertini ◽  
...  
Keyword(s):  
Fly Ash ◽  
Surface Area ◽  
Power Plants ◽  
Coal Fly Ash ◽  
Thermal Power ◽  
Coal Ash ◽  
Mineralogical Composition ◽  
Degree Of Hydrolysis ◽  
High Degree ◽  
Hydrolysis Of

Coal ash is a byproduct of mineral coal combustion in thermal power plants. This residue is responsible for many environmental problems because it pollutes soil, water, and air. Thus, it is important to find ways to reuse it. In this study, coal fly ash, obtained from the Presidente Médici Thermal Power Plant, was utilized in the preparation of ceramic supports for the immobilization of the enzyme invertase and subsequent hydrolysis of sucrose. Coal fly ash supports were prepared at several compaction pressures (63.66–318.30 MPa) and sintered at 1200°C for 4 h. Mineralogical composition (by X-ray diffraction) and surface area were studied. The ceramic prepared with 318.30 MPa presented the highest surface area (35 m2/g) and amount of immobilized enzyme per g of support (76.6 mg/g). In assays involving sucrose inversion, it showed a high degree of hydrolysis (around 81%) even after nine reuses and 30 days’ storage. Therefore, coal fly ash ceramics were demonstrated to be a promising biotechnological alternative as an immobilization support for the hydrolysis of sucrose.

scholarly journals Effect of Enzyme Modified Soymilk on Rennet Induced Gelation of Skim Milk

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3084 ◽  
Author(s):  
Kaixin Li ◽  
Jianjun Yang ◽  
Qigen Tong ◽  
Wei Zhang ◽  
Fang Wang
Keyword(s):  
Electron Microscopy ◽  
Moisture Content ◽  
Skim Milk ◽  
Degree Of Hydrolysis ◽  
Microscopy Imaging ◽  
High Degree ◽  
Physical And Chemical ◽  
Hydrolysis Of ◽  
New Protein ◽  
Scanning Electron

In this study, soymilk was hydrolyzed to different degrees with flavourzyme, and then soymilk and enzyme modified soymilk at various levels were added to skim milk respectively, to generate a mixed gel using rennet. Rheological properties, scanning electron microscopy imaging, and physical and chemical indexes were examined to reveal the effect of enzyme modified soymilk on rennet induced gelation of skim milk. Results showed that soymilk inhibited the aggregation of skim milk, led to a decrease in storage modulus (G’), significantly increased moisture content and curd yield, and the resulting network was coarse. Enzyme modified soymilk with a molecular weight below 20 kDa led to a more uniform curd distribution, which counteracted the reduction of G’ and allowed for the formation of a stronger gel. Both the moisture content and the curd yield increased with the addition of soymilk and enzyme modified soymilk, and overall the effect of adding a high degree of hydrolysis of enzyme modified soymilk was superior. Compared to untreated soymilk, the addition of a certain amount of enzyme modified soymilk resulted in a new protein structure, which would improve the texture of blend cheese.

scholarly journals Influence of type of pre-hair treatment from different types of animal sources on the degree of hydrolysis of keratin

2020 ◽  
Author(s):  
Darina Zheleva ◽  
Margarita Koleva
Keyword(s):  
Disulfide Bonds ◽  
Degree Of Hydrolysis ◽  
Animal Source ◽  
Hydrolysis Process ◽  
Hair Samples ◽  
Animal Hair ◽  
The Difference ◽  
Pre Treatment ◽  
Hydrolysis Of ◽  
Sheep Wool

Keratin biomaterials have many different advantages over other biomolecules. A number of techniques have been studied to prepare keratin hydrolysates. Many of them use strong reagents and the processes take place under very drastic conditions. The present study focuses on the following aspects: producing keratin hydrolysates from various animal sources; application of various methods for extraction; comparison of the type of treatment over the degree of hydrolysis. Sheep wool samples were used, respectively native and alkaline pre-treated and samples of goat hair, respectively native and enzyme pre-treated. The methods used for the hydrolysis of keratin materials are: 1) by sulfotolysis with sodium pyrosulfate and urea; 2) with thioglycolic acid and 3) with sodium hydroxide. The obtained hydrolysates were characterized by qualitative reactions, spectrophotometric and FTIR analysis. It was found that the samples from one and the same animal source show very different properties and different degrees of hydrolysis. The highest degree of hydrolysis was achieved for the pre-treated samples. It was proved that the method of hydrolysis with NaOH is the most appropriate for sheep wool and to a much greater extent for the alkaline treated wool than for the native. The reducing agent: sodium pyrosulfate and urea is the most appropriate for enzyme pre-treated samples of goat skin. Therefore, pre-treatment of animal hair samples facilitates the hydrolysis process and makes it easier to break disulfide bonds. The disadvantage of proteins, and in particular keratins, is the difference in the structure of macromolecules, which are obtained from different animal sources. Therefore, this requires a specific approach to the hydrolysis of keratin from each individual animal source.

NEW FUNCTIONAL FOODS FROM TWO COMPONENTS GRAIN MIXTURE (WHEAT AND FLAX)

1970 ◽  
pp. 54-58
Author(s):  
Е. Р. Meleshkina ◽  
G. N. Pankratov ◽  
I. S. Vitol ◽  
R. Kh. Kandrokov
Keyword(s):  
Wheat Flour ◽  
Functional Foods ◽  
Fat Content ◽  
Innovative Technology ◽  
Degree Of Hydrolysis ◽  
Wheat Grain ◽  
Enzyme Preparations ◽  
Two Component ◽  
Processed Products ◽  
Hydrolysis Of

This paper describes the new functional products (compositional flour, bran) obtained from a two-component grain mixture according to the developed innovative technology. It was shown that the preliminary peeling of wheat grain does not affect the distribution of fat in the milled products, the fat content in flour is proportional to the amount of flax in a two-component grain mixture. The content of linoleic acid (w-6) in the sample of wheat flour is 2.4 times less than in the sample of wheat-flax flour (0.53% vs. 1.27%); the content of linolenic acid (w-3) in the sample of wheat flour is 53.7 times less than in the sample of wheat-flax flour (0.035% vs. 1.88%). The fat content in bran of two-component grain mixtures of wheat and flax is about 2 times higher than their content in wheat bran. Enriched foods have been obtained, products from which will help to compensate for the lack of polyunsaturated fatty acids (PUFAs) of the w-3 family in the diet of a modern person. The effectiveness of enzyme preparations of proteolytic and cellulolytic action in the hydrolysis of biopolymers of processed products of two-component mixtures based on wheat and flax (bran) was studied. It is shown that the use of biotechnological modification methods allows to obtain structurally modified products with a certain degree of hydrolysis of biopolymers with the aim of using them to create functional food products.

scholarly journals Optimization of the Hydrolysis of Safflower Oil for the Production of Linoleic Acid, Used as Flavor Precursor

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Marya Aziz ◽  
Florence Husson ◽  
Selim Kermasha
Keyword(s):  
Linoleic Acid ◽  
Candida Rugosa ◽  
Thermomyces Lanuginosus ◽  
Degree Of Hydrolysis ◽  
Safflower Oil ◽  
Lipozyme Tl Im ◽  
Porcine Pancreas ◽  
Experimental Findings ◽  
High Degree ◽  
Hydrolysis Of

Commercial lipases, from porcine pancreas (PPL),Candida rugosa(CRL), andThermomyces lanuginosus(Lipozyme TL IM), were investigated in terms of their efficiency for the hydrolysis of safflower oil (SO) for the liberation of free linoleic acid (LA), used as a flavor precursor. Although PPL, under the optimized conditions, showed a high degree of hydrolysis (91.6%), its low tolerance towards higher substrate concentrations could limit its use for SO hydrolysis. In comparison to the other investigated lipases, Lipozyme TL IM required higher amount of enzyme and an additional 3 h of reaction time to achieve its maximum degree of SO hydrolysis (90.2%). On the basis of the experimental findings, CRL was selected as the most appropriate biocatalyst, with 84.1% degree of hydrolysis. The chromatographic analyses showed that the CRL-hydrolyzed SO is composed mainly of free LA.

Studi Eksegetis Yohanes 1:1-18 Sebagai Apologetik Terhadap Kristologi Saksi Yehuwa

2016 ◽  
Vol 1 (2) ◽  
pp. 1-41
Author(s):  
Pangeran Manurung
Keyword(s):  
Striking Difference ◽  
Human Being ◽  
John 1 ◽  
Jehovah’S Witnesses ◽  
Jehovah's Witnesses ◽  
Jehovah's Witness ◽  
Search Results ◽  
The Bible ◽  
God The Father ◽  
The Difference

Eksegesa John 1 : 1-18 shows that the Jehovah's Witness teachings deviate from the truth of the Bible and dangerous for Christians . The danger Christology of Jehovah's Witnesses should be bringing us to the prudence and discretion to reject it . It can be said that Jehovah's Witnesses do not include Christianity in accordance with the search results against their teachings . first ; they do not recognize the Bible that has been issued by the Indonesian National Bible Institute and consider if the Bible has too much harm to use their own New Translation of the Holy Scriptures that have been proven not a translation , but just a collection of interpretations and teachings of their leader alone . second ; Jehovah's Witnesses do not acknowledge Jesus as Lord and Savior only . They simply believe that salvation is obtained through belief in Jehovah and his kingdom and perform service message and follow the trial associations .                Before errors interfere Christology Christology of Jehovah's Witnesses Bible , please note that the topic of Christology is the difference between Christianity and other religions . This discussion has also become one of the topics that face many attacks from the outside or from within Christianity , either in the form of religion , philosophy , and ideology . The debate on this topic appeared since the beginning of Christianity , and give rise to a long and complex debate for nearly three centuries ( 300 years ) !! . Such debates will continue to exist throughout the period and just a rehash issues that had once appeared . And Christians should study the various debates and views of the ever emerging that are not easily fooled by the views back to this era .Eksegesa John 1 : 1-18 has been done and produce a biblical Christology and biblical correct . The truth is not in doubt because of the analysis conducted in accordance with the procedures and rules that apply in general . Now if Christology Christology of John compared with Jehovah's Witnesses, it will show a striking difference . Once observed , Christology Witnesses builds upon the interpretation of individuals who previously have had a negative Christological doctrine .                Conclusion those who think that Jesus is the firstborn of Creation ; Jesus was a human being ; Jesus is God in creating a peer ; Jesus lower than God , Jesus is the Angel Gabriel , and other Christological doctrine which basically degrading nature of Christ is a form of insult to the majesty of Christ . The Bible clearly and emphatically teaches that Christ is God incarnate , private alpha and omega , the creator of all that exists , and the equivalent of God the Father . Summing Christ as superior human or clear eldest creation is false teachings . The followers of Jehovah's Witnesses must repent. Amen

Polarographic study of hydrolysis of [8-lysine]vasopressin and its derivatives with blood serum of pregnant women

1980 ◽  
Vol 45 (4) ◽  
pp. 1099-1108 ◽  
Author(s):  
Mikuláš Chavko ◽  
Michal Bartík ◽  
Evžen Kasafírek
Keyword(s):  
Blood Serum ◽  
Pregnant Women ◽  
Degree Of Hydrolysis ◽  
Polarographic Study ◽  
Ph Optimum ◽  
Lysine Vasopressin ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of ◽  
Vasopressin Analogues

A polarographic study of the hydrolysis of [8-lysine]vasopressin and some hormonogens of the vasopressin series with the blood serum of women in the last week of pregnancy was studied. The dependence of hydrolysis on pH (pH optimum: 7.4-7.50, substrate concentration (Km 1.2 . 10-5M), pH stability and thermal stability were determined. The rate of hydrolysis of individual vasopressin analogues decreases in the order: [8-lysine]vasopressin > Nα-glycyl-prolyl[8-lysine]-vasopressin > Nα-leucyl-[8-lysine]vasopressin > Nα-alanyl-[8-lysine]vasopressin > Nα-phenyl alanyl-[8-lysine]vasopressin > Nα-diglycyl-[8-lysine]vasopressin > Nα-prolyl-[8-lysine]vasopressin > Nα-triglycyl-[8-lysine]vasopressin > Nα-sarcosyl-glycyl-[8-lysine]vasopressin. The degree of hydrolysis gradually increases to a multiple with the length of the pregnancy in consequence of the presence of oxytocine. However, vasopressin is also hydrolysed to a small extent with the enzymes from the blood sera of non-pregnant women. Under similar analytical conditions oxytocin was not hydrolysed with the sera of non-pregnant women and therefore oxytocin is a more suitable substrate than vasopressin for polarographic determination of serum oxytocinase.

Research on Enzymatic Hydrolysis of Whey Protein

2013 ◽  
Vol 411-414 ◽  
pp. 3205-3209
Author(s):  
Fang Qian ◽  
Lei Zhao ◽  
Shu Juan Jiang ◽  
Guang Qing Mu
Keyword(s):  
Enzymatic Hydrolysis ◽  
Whey Protein ◽  
Degree Of Hydrolysis ◽  
Quadratic Regression ◽  
Orthogonal Regression ◽  
Single Factor Analysis ◽  
Verification Test ◽  
Enzyme Dosage ◽  
Hydrolysis Conditions ◽  
Hydrolysis Of

Based on single factor analysis for the enzymatic hydrolysis of whey protein, papain was selected as the optimal enzyme and its enzymatic hydrolysis conditions were optimized by the quadratic regression orthogonal rotary test. The orthogonal regression model for degree of hydrolysis (DH) to three factors including temperature (X1), time (X2), enzyme dosage (X3) was established as follow: DH=10.40+0.22X1+0.30X2+1.31X3+0.019X1X2+0.011X1X3-0.039X2X3-0.39X12-0.16X22-0.40X32, Verification test showed a DH of 11.7% was obtained at the optimal hydrolysis condition of 56.6°C, 113.8 min and enzyme 8213.7 U /g protein, which basically consisted with the model theoretical value.

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