ENZYMIC HYDROLYSIS OF A GLUCOMANNAN FROM JACK PINE (PINUS BANKSIANA LAMB.)

1961 ◽  
Vol 39 (4) ◽  
pp. 815-826 ◽  
Author(s):  
O. Perila ◽  
C. T. Bishop
Keyword(s):  
Pinus Banksiana ◽  
Jack Pine ◽  
Molar Ratio ◽  
Enzymic Hydrolysis ◽  
Hydrolysis Of

A crude glucomannan was isolated from jack pine holocellulose in 17% yield. Repeated delignification and copper complexing of this product provided a purified glucomannan (5% of the holocellulose) containing glucose, mannose, galactose, and xylose in a molar ratio of 10:25:1:1. This polysaccharide was hydrolyzed by a commercial hemicellulase preparation, the cleavage products being removed by continuous dialysis of the reaction mixture. The following oligosaccharides were isolated from the hydrolyzate and identified; yields are based on the glucomannan:[Formula: see text]

CONSTITUTION OF AN ARABOGALACTAN FROM JACK PINE (PINUS BANKSIANA LAMB)

1957 ◽  
Vol 35 (9) ◽  
pp. 1010-1019 ◽  
Author(s):  
C. T. Bishop
Keyword(s):  
Methyl Ether ◽  
Pinus Banksiana ◽  
Jack Pine ◽  
Degree Of Polymerization ◽  
Average Degree ◽  
Water Soluble ◽  
Molar Ratio ◽  
Hydrolysis Of ◽  
Homogeneous Hydrolysis

A water soluble arabogalactan isolated from jack pine was shown to have a molar ratio of arabinose to galactose of 1:13, and a number average degree of polymerization of 53 ± 3. Fractionation data and electrophoresis indicated that the arabogalactan was homogeneous. Hydrolysis of the methyl ether of the polysaccharide yielded 2,3,5-tri-O-methyl-L-arabinose (4 moles); 2,3,4,6-tetra-O-methyl-D-galactose (12–13 moles); 2,3,4-tri-O-methyl-D-galactose (19 moles); 2,6-di-O-methyl-D-galactose (1 mole); and 2,4-di-O-methyl-D-galactose (14 moles). Some features of the structure of the arabogalactan are discussed on the basis of these results.

CONSTITUTION OF A GLUCOMANNAN FROM JACK PINE (PINUS BANKSIANA, LAMB)

1960 ◽  
Vol 38 (6) ◽  
pp. 793-804 ◽  
Author(s):  
C. T. Bishop ◽  
F. P. Cooper
Keyword(s):  
Pinus Banksiana ◽  
Group Analysis ◽  
Periodate Oxidation ◽  
Jack Pine ◽  
Degree Of Polymerization ◽  
Molar Ratio ◽  
Partition Chromatography ◽  
Pine Wood ◽  
Terminal Units ◽  
End Group

A hemicellulose fraction from jack pine wood has been shown to contain D-mannose, D-glucose, and D-galactose in a molar ratio of 49:17:2. The glucomannan was electrophoretically homogeneous and showed a degree of polymerization of 18–21 by three different methods of end group analysis. Methylation and hydrolysis yielded the following O-methyl ethers: 2,3,4,6-tetra-O-methyl-D-glucose (2.8 moles); 2,3,4,6-tetra-O-methyl-D-galactose (1 mole); 2,3,6-tri-O-methyl-D-mannose (52 moles); 2,3,6-tri-O-methyl-D-glucose (15.3 moles); di-O-methyl-D-glucose (1 mole); di-O-methyl-D-galactose (2 moles). Lack of survival of any monosaccharides in the periodate-oxidized glucomannan showed that there was no branching through C2 or C3 of any of the units. Gas–liquid partition chromatography was used to analyze products from methylation and hydrolysis and from periodate oxidation and reduction of the polysaccharides. The results showed that the glucomannan from jack pine was composed of 1 → 4 linked β-D-mannose and β-D-glucose residues with D-galactose residues present as non-reducing terminal units. Branching, if any, must occur through C6 of units making up the polysaccharide. This structure is compared with those of glucomannans found in other soft woods.

scholarly journals Synthesis, Structure and In Vitro Anticancer Activity of Pd(II) Complex of Pyrazolyl-s-Triazine Ligand; A New Example of Metal-Mediated Hydrolysis of s-Triazine Pincer Ligand

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 119
Author(s):  
Jamal Lasri ◽  
Matti Haukka ◽  
Hessa H. Al-Rasheed ◽  
Nael Abutaha ◽  
Ayman El-Faham ◽  
...  
Keyword(s):  
Thermal Conditions ◽  
Molar Ratio ◽  
Chloride Salt ◽  
Pincer Ligand ◽  
Hydrogen Bonding Interactions ◽  
Square Planar ◽  
Hirshfeld Analysis ◽  
Hydrolysis Of ◽  
Mcf 7

The square planar complex [Pd(PT)Cl(H2O)]*H2O (HPT: 6-(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazine-2,4(1H,3H)-dione) was obtained by the reaction of 2-methoxy-4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazine (MBPT) pincer ligand with PdCl2 in a molar ratio (1:1) under thermal conditions and using acetone as a solvent. The reaction proceeded via C-N cleavage of one C-N moiety that connects the pyrazole and s-triazine combined with the hydrolysis of the O-CH3 group. The reaction of the chloride salt of its higher congener (PtCl2) gave [Pt(3,5-dimethyl-1H-pyrazole)2Cl2]. The crystal structure of [Pd(PT)Cl(H2O)]*H2O complex is stabilized by inter- and intra-molecular hydrogen bonding interactions. Hirshfeld analysis revealed that the H...H (34.6%), O...H (23.6%), and Cl...H (7.8%) interactions are the major contacts in the crystal. The charges at Pd, H2O, Cl and PT are changed to 0.4995, 0.2216, −0.4294 and −0.2917 instead of +2, 0, −1 and −1, respectively, using the MPW1PW91 method. [Pd(PT)Cl(H2O)]*H2O complex has almost equal activities against MDA-MB-231 and MCF-7 cell lines with IC50 of 38.3 µg/mL.

scholarly journals Optimized 5-Fluorouridine Prodrug for Co-Loading with Doxorubicin in Clinically Relevant Liposomes

Pharmaceutics ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 107
Author(s):  
Debra Wu ◽  
Douglas Vogus ◽  
Vinu Krishnan ◽  
Marta Broto ◽  
Anusha Pusuluri ◽  
...  
Keyword(s):  
Single Agent ◽  
Molar Ratio ◽  
Control Group ◽  
Drug Tolerability ◽  
Breast Cancer Model ◽  
In Vivo Testing ◽  
Chemical Profiles ◽  
Hydrolysis Of ◽  
Doxorubicin Liposomes

Liposome-based drug delivery systems have allowed for better drug tolerability and longer circulation times but are often optimized for a single agent due to the inherent difficulty of co-encapsulating two drugs with differing chemical profiles. Here, we design and test a prodrug based on a ribosylated nucleoside form of 5-fluorouracil, 5-fluorouridine (5FUR), with the final purpose of co-encapsulation with doxorubicin (DOX) in liposomes. To improve the loading of 5FUR, we developed two 5FUR prodrugs that involved the conjugation of either one or three moieties of tryptophan (W) known respectively as, 5FUR−W and 5FUR−W3. 5FUR−W demonstrated greater chemical stability than 5FUR−W3 and allowed for improved loading with fewer possible byproducts from tryptophan hydrolysis. Varied drug ratios of 5FUR−W: DOX were encapsulated for in vivo testing in the highly aggressive 4T1 murine breast cancer model. A liposomal molar ratio of 2.5 5FUR−W: DOX achieved a 62.6% reduction in tumor size compared to the untreated control group and a 33% reduction compared to clinical doxorubicin liposomes in a proof-of-concept study to demonstrate the viability of the co-encapsulated liposomes. We believe that the new prodrug 5FUR−W demonstrates a prodrug design with clinical translatability by reducing the number of byproducts produced by the hydrolysis of tryptophan, while also allowing for loading flexibility.

Variation in Quantity of Methanol Recovered from Raisins

1963 ◽  
Vol 46 (2) ◽  
pp. 341-343
Author(s):  
M Alice Brown ◽  
James R Woodward ◽  
Floyd DeEds
Keyword(s):  
Methyl Ester ◽  
Esterase Activity ◽  
Enzymic Hydrolysis ◽  
Methanol Content ◽  
Naturally Occurring ◽  
Pectin Esterase ◽  
Hydrolysis Of

Abstract The amount of naturally occurring methanol in fruit must be known so that the quantity left as fumigation residue can be determined. In a study of methanol content of raisins, which had given inconsistent results, the raisins were subjected to different conditions of treatment immediately prior to methanol determination. Conditions that favored pectin esterase activity gave higher values for methanol content than conditions known to inactivate enzymes. Evidence was also obtained that both chemical and enzymic hydrolysis of methyl ester groups of pectic materials occur during analysis.

scholarly journals Permeability of muscle capillaries to small heme-peptides. Evidence for the existence of patent transendothelial channels.

1975 ◽  
Vol 64 (3) ◽  
pp. 586-607 ◽  
Author(s):  
N Simionescu ◽  
M Siminoescu ◽  
G E Palade
Keyword(s):  
Plasma Proteins ◽  
Intercellular Junctions ◽  
Rat Diaphragm ◽  
Enzymic Hydrolysis ◽  
Graphic Analysis ◽  
Heme Peptides ◽  
Future Work ◽  
Hydrolysis Of ◽  
Muscle Capillaries

Two heme-peptides (HP) of about 20-A diameter (heme-undecapeptide [H11P], mol wt approximately 1900 and heme-octapeptide [H8P], mol wt approximately 1550), obtained by enzymic hydrolysis of cytochrome c, were sued as probe molecules in muscle capillaries (rat diaphragm). They were localized in situ by a perixidase reaction, enhanced by the addition of imidazole to the incubation medium. Chromatography of plasma samples showed that HPs circulate predominantly as monomers for the duration of the experiments and are bound by aldehyde fixatives to plasma proteins to the extent of approximately 50% (H8P) to approximately 95% (H11P). Both tracers cross the endothelium primarily via plasmalemmal vesicles which become progressively labeled (by reaction product) from the blood front to the tissue front of the endothelium, in three successive resolvable phases. By the end of each phase the extent of labeling reaches greater than 90% of the corresponding vesicle population. Labeled vesicles appear as either isolated units or chains which form patent channels across the endothelium. The patency of these channels was checked by specimen tilting and graphic analysis of their images. No evidence was found for early or preferential marking of the intercellular junctions and spaces by reaction product. It is concluded that the channels are the most likely candidate for structural equivalents of the small pores of the capillary wall since they are continuous, water-filled passages, and are provided with one or more strictures of less than 100 A. Their frequency remains to be established by future work.

Investigation of the products of an enzymic hydrolysis of collagens

Biochemistry ◽  
1969 ◽  
Vol 8 (12) ◽  
pp. 4716-4723 ◽  
Author(s):  
Howard B. Bensusan
Keyword(s):  
Enzymic Hydrolysis ◽  
Hydrolysis Of

scholarly journals Constancy of the optimum temperature of an enzyme under varying concentrations of substrate and of enzyme

1914 ◽  
Vol 88 (602) ◽  
pp. 258-262
Keyword(s):  
Experimental Evidence ◽  
Aspergillus Oryzae ◽  
Hydrolytic Enzyme ◽  
Fixed Duration ◽  
Optimum Temperature ◽  
Enzymic Hydrolysis ◽  
Main Interest ◽  
General Law ◽  
The Moment ◽  
Hydrolysis Of

In a recent paper a new enzymic relation is recorded. For the enzymic hydrolysis of salicin—by the enzyme which Gabriel Bertrand and the author have named salicinase —it is found that, in an action of fixed duration, the temperature of greatest activity of the ferment is always the same, whatever the dilutions of substrate and of enzyme adopted for the determination. In other words, the duration of the action being constant, the optimum tem­perature of the ferment is independent of the concentration both of the substrate and of the enzyme. The observation is suggestive: if true of one enzyme it may be true of all, and possibly becomes the enunciation of a general law. Herein, for the moment, lies its main interest. In the present paper further experimental evidence for this hypothesis in given, in the case of another hydrolytic enzyme, the maltase of Aspergillus oryzæ (taka-diastase).

Oligomeric stannoxanes

1968 ◽  
Vol 46 (14) ◽  
pp. 2409-2413 ◽  
Author(s):  
Shmuel Migdal ◽  
David Gertner ◽  
Albert Zilkha
Keyword(s):  
Dicarboxylic Acids ◽  
Molar Ratio ◽  
Sodium Salts ◽  
Interfacial Conditions ◽  
Organotin Polyesters ◽  
Basic Hydrolysis ◽  
Hydrolysis Of

The controlled basic hydrolysis of tetrabutyl-1,3-dichlorodistannoxane under interfacial conditions was found to lead to α,ω-dichlorooligostannoxanes, Cl(SnBu2O)nSnBu2Cl, n being controlled by the molar ratio of base to distannoxane. These oligostannoxanes were identical with those prepared by other methods. They were used in the preparation of oligostannoxane dicarboxylates and organotin polyesters, having stannoxane recurring units in their backbone, by reaction with the sodium salts of mono- or dicarboxylic acids under interfacial conditions.

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