scholarly journals A CHROMATOGRAPHIC STUDY OF HYDROLYSIS IN THE FEULGEN NUCLEAL REACTION

1957 ◽  
Vol 3 (1) ◽  
pp. 71-88 ◽  
Author(s):  
Philip S. Woods
Keyword(s):  
Deoxyribonucleic Acid ◽  
Degradation Products ◽  
High Rate ◽  
Chromatographic Technique ◽  
Chromatographic Study ◽  
Hydrolysis Time ◽  
Acid Hydrolysate ◽  
Tissue Sections ◽  
Labile Fraction ◽  
Hydrolysis Of

In a study on Feulgen hydrolysis of frozen-dried alcohol-fixed lily anthers, a chromatographic technique was developed to analyze the acid hydrolysate for some of the degradation products of nucleic acid. Hydrolysis was accomplished by 10 per cent perchloric acid at 20°C., and a typical hydrolysis time-Feulgen intensity curve was obtained, with maximum staining occurring at 19 hours. Microphotometric measurements indicated that the amount of stain per nucleus was no different from amount in nuclei fixed and hydrolyzed by more conventional procedures. Uracil-containing material (from ribonucleic acid) was almost completely separated from thymine-containing material (deoxyribonucleic acid) of tissue sections by acid treatment for 1½ hours. Adenine (purines), as the base, was effectively all removed from the deoxyribonucleic acid at the time of optimum hydrolysis. Detectable amounts of thymine-containing material appeared in the hydrolysate shortly after the onset of hydrolysis; and the amount increased rapidly with increased hydrolysis time. At the time of optimum hydrolysis approximately two-thirds of the total deoxyribonucleic acid thymine was lost. The removal of these thymine-containing fragments was linear with respect to time during the first 24 hours and occurred at a relatively high rate. Removal after 24 hours was also linear but was at a markedly lower rate. These results would suggest that two kinds of deoxyribonucleic acid exist in lily anthers; an acid-labile fraction amounting to approximately three-fourths of the total, and an acid-resistant fraction making up the remainder. In the Feulgen procedure much of the labile fraction is lost by the time of optimum hydrolysis and is not stained; most of the stable fraction remains in the tissue and is stained. In light of these findings the use of the Feulgen method as a means of determining cytochemically relative amounts of deoxyribonucleic acid in nuclei by measuring their Feulgen dye content was discussed.

Influence of high hydrostatic pressure on the proteolysis of β-lactoglobulin A by trypsin

2006 ◽  
Vol 73 (1) ◽  
pp. 121-128 ◽  
Author(s):  
Rosa Chicón ◽  
Josefina Belloque ◽  
Isidra Recio ◽  
Rosina López-Fandiño
Keyword(s):  
High Pressure ◽  
Degradation Products ◽  
Thiol Group ◽  
Hydrolysis Time ◽  
Structural Modifications ◽  
Disulphide Bonds ◽  
Free Thiol Group ◽  
Β Lactoglobulin ◽  
Hydrolysis Of ◽  
Tryptic Hydrolysis

This work describes the effect of the hydrolysis time and pressure (0·1–400 MPa) on the proteolysis of β-lactoglobulin A (β-lg A) with trypsin, either conducting hydrolysis of β-lg under pressure or hydrolysing β-lg that was previously pressure treated. Pressurisation, before or during enzyme treatments, enhanced tryptic hydrolysis of β-lg. Trypsin degraded pressure-modified β-lg and pressure-induced β-lg aggregates, favouring proteolysis to the intermediate degradation products: (Val15-Arg40), (Val41-Lys69)S-S(Leu149-Ile162) and (Val41-Lys70)S-S(Leu149-Ile162). These were further cleaved at the later stages of proteolysis to yield: (Val15-Tyr20), (Ser21-Arg40), (Val41-Tyr60), (Trp61-Lys69)S-S(Leu149-Ile162) and (Trp61-Lys70)S-S(Leu149-Ile162). Particularly, in the tryptic hydrolysates of pre-pressurized β-lg, two other fragments linked by disulphide bonds: (Lys101-Arg124)S-S(Leu149-Ile162) and (Tyr102-Arg124)S-S(Leu149-Ile162), were found. These corresponded to rearrangement products induced by SH/SS exchange between the free thiol group of Cys121 and Cys160, that normally forms the disulphide bond Cys66-Cys160. In the light of these results, structural modifications of β-lg under high pressure are discussed.

Analysis of the hydrolysates from cured and uncured urea-formaldehyde (UF) resins with two F/U mole ratios

Holzforschung ◽  
2018 ◽  
Vol 72 (9) ◽  
pp. 759-768 ◽  
Author(s):  
Muhammad Adly Rahandi Lubis ◽  
Byung-Dae Park
Keyword(s):  
Functional Groups ◽  
Degradation Products ◽  
Urea Formaldehyde ◽  
Chemical Species ◽  
Gel Permeation Chromatography ◽  
Hydrolysis Time ◽  
Water Hydrolysis ◽  
Hydrolysis Of ◽  
C Nmr

Abstract Uncured and cured urea-formaldehyde (UFcured) resins prepared with formaldehyde/urea (F/U) mole ratios of 1.0 and 1.2 and at the catalyst levels of 1, 2 and 3% NH4Cl were hydrolyzed for 5, 15 and 30 min and the degradation products were evaluated using gel permeation chromatography, Fourier-transform infrared (FTIR) and liquid carbon-13 nuclear magnetic resonance (13C-NMR) spectroscopies. The molar masses of the degradation products, their functional groups and structures were determined. An extended hydrolysis time and higher catalyst levels resulted in compounds with higher molar masses. Similar functional groups and distribution of chemical species were found by both FTIR and 13C-NMR spectroscopies in the hydrolysates of UFcured, indicating water hydrolysis of hydroxymethyl groups and then methylene linkages. Methylene linkages and mono- and tri-hydroxymethyl ureas were mainly responsible for the liberation of formaldehyde from UFcured during hydrolysis. The indicated compounds are believed to contribute to the long-term release of formaldehyde from the resins. This is the first systematic report on the composition of UFcured hydrolysates.

scholarly journals Optimization of hydrolysis conditions for xylans and straw hydrolysates by HPLC analysis

2021 ◽  
Author(s):  
Alexander Beckendorff ◽  
Anne Lamp ◽  
Martin Kaltschmitt
Keyword(s):  
Sulfuric Acid ◽  
Acid Concentration ◽  
Hplc Analysis ◽  
Degradation Products ◽  
Sulfuric Acid Concentration ◽  
Corn Cob ◽  
Hydrolysis Time ◽  
Conversion Rates ◽  
Hydrolysis Temperature ◽  
Hydrolysis Of

AbstractOligosaccharide analysis is commonly done by acid hydrolysis and following HPLC analysis. A major problem is the incomplete hydrolysis of oligosaccharides and disaccharides and the increasing formation of volatile furfural from pentose monomers and hydroxymethylfurfural (HMF) from hexose monomers. This paper optimizes the conditions of hydrolysis approaches and proposes a method for oligosaccharide quantification. The optimal condition for hydrolysis of model xylan from corn cob was found to be for 100 °C hydrolysis temperature, 120 min hydrolysis time, and 2 wt% sulfuric acid concentration. Under these conditions, the total free and bound xylose yield was 77.4% and hemicellulose conversion 87.4% respectively; no degradation products were found. The optimal conditions for hydrolysis of model xylan from beech wood were found to be for 120 °C hydrolysis temperature, 120 min hydrolysis time, and 2 wt% sulfuric acid concentration. Under these conditions, the total free and bound xylose yield was 65.1% and hemicellulose conversion 70.5% respectively; no degradation products were found. For pentosan hydrolysate, conditions were further optimized (110 °C, 60 min, 2 wt% H2SO4). Standard addition of xylan from the corn cob for hydrolysation showed similar conversion rates (< 2% deviation); no matrix effects were detected.

Peritoneal Fluid and Plasma Fibrinolytic Activity in Women with Pelvic Inflammatory Disease

1992 ◽  
Vol 68 (02) ◽  
pp. 102-105 ◽  
Author(s):  
P J Dörr ◽  
E J P Brommer ◽  
G Dooijewaard ◽  
H M Vemer
Keyword(s):  
Pelvic Inflammatory Disease ◽  
Inflammatory Disease ◽  
Peritoneal Fluid ◽  
Fibrinolytic Activity ◽  
Degradation Products ◽  
Adhesion Formation ◽  
High Rate ◽  
Control Group ◽  
The Difference ◽  
Fibrinolytic Parameters

SummaryPrevious studies have shown that the fibrinolytic activity of peritoneum is depressed in local inflammation. We measured fibrinolytic parameters in peritoneal fluid and in plasma of 10 women with pelvic inflammatory disease (PID). Nine women, in whom laparoscopy for sterilisation was performed, served as a control group.In the peritoneal fluid of women with PID, PAI-Ag, t-PA-Ag and u-PA-Ag were many times higher than in the control group. In contrast to the antigens which may be present in inert complexes, the potentially active compounds, measured as t-PA activity and plasmin-activable scu-PA, were not significantly different in the two groups, and in none of the samples was the active enzyme tcu-PA detectable. Nevertheless, the mean peritoneal fluid TDP and FbDP concentrations were about twenty times higher in the PID group than in the control group. In plasma of PID patients, none of the parameters except u-PA-Ag differed from those in the control group. The difference between control and patient plasma u-PA-Ag was statistically significant, but too small to attach any relevance to the observation.Our data suggest that, in contrast to the classical concept of decreased fibrinolytic activity as a cause of adhesion formation, intraperitoneal fibrinolysis is enhanced in peritoneal inflammation through stimulation of the local production of t-PA and u-PA. Despite concomitant production of PAI, fibrinolysis occurs at a high rate, resulting in high levels of fibrin degradation products. Since this activated fibrinolysis does not meet the demand, therapeutic enhancement should be considered to prevent adhesions.

Outcome of Treatment of Deep-Vein Thrombosis with Urokinase: Relationship to Dosage, Duration of Therapy, Age of the Thrombus and Laboratory Changes

1984 ◽  
Vol 51 (02) ◽  
pp. 236-239 ◽  
Author(s):  
A D’Angelo ◽  
P M Mannucci
Keyword(s):  
Degradation Products ◽  
High Rate ◽  
Bleeding Complications ◽  
Vein Thrombosis ◽  
Treatment Regimens ◽  
Duration Of Therapy ◽  
Laboratory Changes ◽  
Deep Vein ◽  
Dose Dependent ◽  
Higher Doses

SummaryForty-one patients with phlebographically proven DVT of the popliteal, femoral or iliac veins were treated with different regimens of urokinase (UK) given by continuous intravenous infusion. The four groups were comparable with respect to localization, extension and estimated age of the thrombi. Another phlebographic picture was taken within 48 hr after the end of UK infusion. Substantial lysis had occurred in 2 of 10 patients treated with 1500 U/kg/h for 2 days, in 4 of 11 treated with 2500/U/kg/h for 3 days, in 2 of 10 treated with 2500 U/kg/h for 7 days and in 4 of 10 treated with 4000 U/kg/h for 4 days. Only thrombi younger than 8 days could be lysed, with 61% (8/13) rate of lysis for thrombi less than 5 days old. Bleeding complications were observed more frequently with the higher doses and longer durations of therapy. The four treatment regimens all induced dose-dependent changes in fibrinogen, fibrin(ogen) degradation products, plasminogen and antiplasmin. Neither pre- nor postinfusion values of these parameters could differentiate patients with lysis from those without lysis. It is concluded that UK can provoke a high rate of thrombolysis of DVT treated early after the appearance of symptoms but that there is no relationship between UK-induced modifications of fibrinolysis and the outcome of therapy.

Urea hydrolysis and inorganic N in a Luvisol after application of fertiliser containing rare-earth elements

Soil Research ◽  
2003 ◽  
Vol 41 (4) ◽  
pp. 741 ◽  
Author(s):  
Xingkai Xu ◽  
Zijian Wang ◽  
Yuesi Wang ◽  
Kazuyuki Inubushi
Keyword(s):  
Rare Earth ◽  
Rare Earths ◽  
Substantial Reduction ◽  
Application Rate ◽  
Urea Hydrolysis ◽  
High Rate ◽  
Short Term ◽  
N Content ◽  
N Fertilisers ◽  
Hydrolysis Of

In recent decades, Chinese agriculturists have used rare-earth-containing fertilisers as basal fertilisers together with N fertilisers (e.g. urea). We studied urea hydrolysis and its hydrolysis products in a laboratory experiment using urea-N fertiliser with rare earths at rates from 0.5 to 50% (w/w). The results indicated that application of rare earths at a high rate could result in a short-term inhibition of urea hydrolysis and an increase in soil (NH4+ + NO3– + NO2–)-N content. When the application rate of rare earths was higher than 5% of the applied urea-N (corresponding to 10 mg/kg soil), soil exchangeable NH4+-N content increased significantly following the hydrolysis of the applied urea. Increasing the application rate of rare earths appeared to reduce the content of soil urea-derived (NO3– + NO2–)-N. A substantial reduction in soil pH was found immediately after application of rare earths and urea. We conclude that application of rare earths at >10 mg/kg may lead to a substantial increase in the content of urea-derived N in the soil, via the inhibition of urea hydrolysis and nitrification.

Investigation of acid hydrolysis for carbohydrate analysis in kraft black liquor

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Silvia Maitz ◽  
Marlene Kienberger
Keyword(s):  
Acid Hydrolysis ◽  
High Performance ◽  
Degradation Products ◽  
Black Liquor ◽  
Amperometric Detection ◽  
Kraft Process ◽  
Kraft Black Liquor ◽  
Carbohydrate Degradation ◽  
Reliable Detection ◽  
Hydrolysis Of

Abstract Black liquor (BL) from the kraft process is considered a promising feedstock for several biorefinery scenarios. Besides lignin and carboxylic acids, this liquor also contains hemicelluloses and their degradation products. A simple and reliable detection of those is of importance for further processing of the liquor. The present paper presents a thorough investigation of quantitative analysis of carbohydrates, by performing acid hydrolysis experiments with a concentrated BL sample of 44% total dry solids. The hydrolysates were then analysed for the four monosaccharides arabinose, xylose, galactose and glucose, by high performance ion chromatography (HPIC) with pulsed amperometric detection. The amount of sulphuric acid needed for complete hydrolysis of the carbohydrates was determined in the range of 3.5–5 mol kg−1 of BL. A lower acid concentration led to insufficient liberation of galactose and glucose, while higher acid concentrations led to degradation of arabinose and xylose. The carbohydrate degradation was also investigated over time for different dilutions and hydrolysis temperatures. These experiments confirmed that the hexoses require considerably harsher conditions for complete liberation compared to xylose and arabinose. The use of internal recovery standards (RSs) was tested; the highest recoveries were obtained by direct spiking of the samples with the RS prior to hydrolysis.

scholarly journals Complexing power of hydro-soluble degradation products from γirradiated polyvinylchloride: influence on Eu(OH)3(s) solubility and Eu(III) speciation in neutral to alkaline environment

2017 ◽  
Vol 105 (8) ◽  
Author(s):  
Pascal E. Reiller ◽  
Elodie Fromentin ◽  
Muriel Ferry ◽  
Adeline Dannoux-Papin ◽  
Hawa Badji ◽  
...  
Keyword(s):  
Oxidation State ◽  
Alkaline Hydrolysis ◽  
Degradation Products ◽  
Alkaline Environment ◽  
Hydrolysis Of

AbstractThe complexing power of hydrosoluble degradation products (HDPs) from an alkaline hydrolysis of a 10 MGy γ-irradiated polyvinylchloride is studied. The complexation of Eu(III), as an analogue of lanthanide and actinide radionuclides at their +III oxidation state for oxygen containing functions, is evidenced both from the increasing of Eu(OH)

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