Showing papers on "Gelatin published in 1975"

Raman scattering of collagen, gelatin, and elastin.

Abstract: The Raman spectra of collagen, gelatin, and elastin are presented. The Raman lines in the latter two spectra are assigned by deuterating the amide N-H groups in gelatin and by studying the superposition spectra of the constituent amino acids. Two lines appear at 1271 and 1248 cm−1 in the spectra of collagen and gelatin that can be assigned to the amide III mode. Possibly, the appearance of two amide III lines is related to the biphasic nature of the tropocollagen molecule, i.e., proline-rich (nonpolar) and proline-poor (polar) regions distributed along the chain. The melting, or collagen-to-gelatin transition, in water-soluble calf skin collagen is studied and the 1248-cm−1 amide III line is assigned to the 31 helical regions of the tropocollagen molecule. Elastin is thought to be mostly random and the Raman spectrum confirms this assertion. Strong amide I and III lines appear at 1668 and 1254 cm−1, respectively, and only weak scattering is observed at 938 cm−1. These features have been shown to be characteristic of the disordered conformation in proteins.

Purification of rheumatoid synovial collagenase and its action on soluble and insoluble collagen.

Abstract: 1 The neutral collagenase released into the culture medium by explants of rheumatoid synovial tissue has been purified by ultrafiltration and column chromatography, utilising Sephadex G-200, Sephadex QAE A-50 and Sephadex G-100 superfine. 2 The final collagenase preparation had a specific activity against thermally reconstituted collagen fibril of 312 μg collagen degraded min−1 mg enzyme protein−1, representing more than a 1000-fold increase over that of the active culture medium. 3 Electrophoresis in polyacrylamide disc-gels with and without sodium dodecyl sulphate showed the enzyme to migrate as a single protein band. Elution experiments from polyacrylamide gels and chromatography columns have provided no evidence for the existence of more than one collagenase. 4 The molecular weight of the enzyme, as determined by dodecylsulphate-polyacrylamide gel electrophoresis, was 33000. 5 Data obtained from studies with the ion-exchange resin and from gel electrophoresis in acid and alkaline buffer systems suggested a basically charged enzyme. 6 It did not hydrolyse the synthetic collagen peptide Pz-Pro-Leu-Gly-Pro-d-Arg and non-specific protease activity was absent. 7 The collagenase attacked undenatured collagen in solution at 25°C resulting in a 58% loss of viscosity and producing the two characteristic products TCA (3/4) and TCB (1/4). 8 At 37°C and pH 8.0 both reconstituted collagen fibrils and gelatin were degraded to peptides of less than 10000 molecular weight. 9 As judged by the release of soluble hydroxyproline peptides and electron microscopic appearances the enzyme degraded human insoluble collagens derived from tendon and soft juxta-articular tissues although rates of attack were less than with reconstituted fibrils. 10 The data suggests that pure rheumatoid synovial collagenase at 37°C and neutral pH can degrade gelatin, reconstituted fibrils and insoluble collagens without the intervention of non-specific proteases. 11 The different susceptibilities of various collagenous substrates to collagenase attack are discussed.

Photographic light-sensitive material

Abstract: A photographic light-sensitive material having improved anti-adhesive properties comprising an uppermost layer containing acid-processed gelatin and a surface active organic fluoro-compound.

Process for producing microcapsules

Abstract: In a process for producing microcapsules of complex hydrophilic colloid material enclosing fine particles of a hydrophobic substance, the improvement characterized in that: An acid-treated gelatin and at least one of carboxy-modified cellulose derivatives are used as the hydrophilic colloid materials, the amount of the cellulose derivative being 1/7 to 1/40 the amount of the gelatin by weight, the cellulose derivative having an average polymerization degree of 50 to 1,000 and a carboxyl substitution degree of 0.4 to 1.5, and The coacervation of the colloid material solution is effected at a pH of 4.8 to 6.0.

Structure and Formation of the Gelatin Gel

Abstract: It was the aim of the present work to investigate the elastically active elements of gelatin gels. There have been several attempts2-5 to convert quantities which change during the course of gelation in the concentration of elastically active clements of the network. All these attempt have in common that the conversion of the reaction coordinate is not bascd on the knowledge of the resulting structure of the gel but merely the benefit of a convenient mathematical formalism suggested an application.The molecular characterization of the gelatin was established by gel permeation chromatography, gel electrophoresis and the measuremen t of light scattering.The structural elements of the gelatin gel were made visible by two independent mcthods of prcparation: ncgative staining and freeze etching. The resulting samples wcrc investigated with the transmission clectron microscope. The fibrous-associationtype structure of the gelatin gel was further morc quantitatively de. eribed by thc measurement of perme...

The lysis effect of bull spermatozoa on gelatin substrate film methodical investigations.

Abstract: Proteolytic activity in the acrosomes of ejaculated bull spermatozoa was demonstrated using an autoradiographic film as a gelatin substrate. Incubation of the spermgelatin adducts at +37 degrees C and 94% humidity, which was kept constant by ventilating an incubator with water-saturated compressed air, yielded reproducible results. Gelatin depolymerisation started adjacent to the posterior segment of the acrosome within 30 to 60 s after application of individual spermatozoa to the substrate membrane and, finally, increased to a white circular digestion area enveloping the entire sperm head. The observed gelatinolysis seems to be mainly caused by acrosin, the trypsin-like acrosomal proteinase. This conclusion is supported by the positive correlation (r = +0.83, P is less than or equal to 0.01) found between the mean values of the lysis areas of individual spermatozoa on gelatin films and the acrosin activity of the sperm population measured with Bz-Arg-OEt as substrate after acidic extraction of the spermatozoa. In addition, prior saturation of the substrate layers with acrosin inhibitor (SSPI-I, II) from boar seminal plasma prevented the lysis reaction. Extraction of acrosin from the spermatozoa before application to the gelatin membranes resulted in a complete loss of any proteolytic activity. If spermatozoa were stored for 4 to 6 days at +4 degrees C or -20 degrees C in Tris buffer and afterwards applied to the substrate layer, lysis areas of individual spermatozoa differed markedly. Spermatozoa from undiluted ejaculated frozen at -20 degrees C showed no proteolytic effect on gelatin films. In general, there was a high correlation (r = +0.83, P is less than or equal 0.01) between the number of "living cells" characterized by live-dead staining and the percentage of spermatozoa active on the substrate membranes.

Process for adhering hydrophilic layers to dimensionally stable polyester films

Abstract: Hydrophilic layers are made to adhere to dimensionally stable polyester film supports by applying to an unstretched or only longitudinally stretched polyester film an adhesive layer from an aqueous coating composition comprising a chlorine-containing copolymer formed of 45 to 99.5 % by weight of at least one of the monomers vinylidene chloride and vinyl chloride, 0.5 to 10 % by weight of an ethylenically unsaturated mono- or dicarboxylic acid or of N-vinyl pyrrolidone, and 0 to 54.5 % by weight of at least one monomer taken from acrylamides, methacrylamides, esters of acrylic acid, methacrylic acid and maleic acid, and N-alkyl maleimides. Immediately thereafter, without drying of the adhesive layer, a subbing layer is applied thereto from an aqueous gelatin solution comprising a plasticizer for the gelatin. After drying of the two layers, they are biaxially or transversally stretched together with the polyester film support, and heat-setted. Finally a hydrophilic layer is applied to the subbing layer. The polyester film may be a film of polyethylene terephthalate and the hydrophilic layer applied to the subbing layer may be a light-sensitive gelatin silver halide emulsion layer.

Reversible extinction of the morphogen in bone matrix by reduction and oxidation of disulfide bonds

Abstract: β-Mercaptoethanol (β-ME) or dithiothreitol (DTT) reduction extinguishes the capacity of bone matrix gelatin to produce new bone following implantation in a muscle pouch. If the reducing solution is used in concentrations of 50 mmoles/l or less, the extinction can be partially reversed by bubbling of oxygen through the solution for one hour. Sulfhydryl group blocking reagents prevent reoxidation of reduced bone gelatin, and restoration of the bone morphogenetic property (BMP). Unspecific borohydride reduction at 37° destroys bone yi yield irreversibly, but at 2° reduction of free aldehyde groups in bone gelatin does not prevent β-ME and DTT reversible extinction. These observations are interpreted to suggest that the disulphide linkage may be an essential part of the biologically active conformation of either anon-collagenous bone morphogenetic polypeptide firmly bound to collagen or a collagen by-product entrapped within a water insoluble gel matrix.

Acidified milk gel and method of producing the same

Abstract: This invention provides for the combination of milk, an acid food juice, sweetening agent, optional acidulent and a thickener comprising gelatin and carboxy methyl cellulose in a palatable, high protein, stable low pH gel. The food juice remains within the product as a finely divided widely dispersed mixture, providing uniformity of flavor without noticeable particles or graininess.

Fractionation of Functional Lymphocytes Sensitized to Basic Encephalitogen on Derivatized Collagen and Gelatin Gels

Abstract: The lymph node cells of basic encephalitogen (BE)-sensitized guinea pigs were fractionated on derivatized collagen and gelatin gels. The population of cells specifically reactive to this antigen can be isolated from derivatized gelatin gels and retain their viability and functionality as assayed in vitro. The specific binding of BE-sensitized cells to BE-derivatized gels comprised between 1 and 2% of the cells applied per plate. The ratio of sensitized cells bound to non-sensitized cells bound ranged between 4 and 6. The viability and functionality of adherent cells detached from collagen gels after enzymatic degradation were impaired. In contrast, the responses obtained with the adherent cell population released from the gelatin gels, by melting at 37°C, were equal or greater than those of the original unfractionated lymph node cell cultures. Furthermore, it was possible to obtain a nonadherent cell population which was virtually completely depleted of the capacity to respond to the sensitizing antigen.

An Antigenic Antimorphogenetic Bone Hydrophobic Glycopeptide (AHG)

Abstract: A hydrophobic glycopeptide, isolated from fresh marrow-free cortical bone of the rat, extinguished the bone morphogenetic response of insoluble bone matrix gelatin which otherwise invariably produces new bone from migrating mesenchymal cells after implantation in muscle of the rat. Incubation of the 10 to 100 pg of the glycopeptide per milligram of bone gelatin in phosphate or Tris-HCl buffer, pH = 7.4, for 2khours recombines the hydrophobic polypeptide and gelatin. Incubated with doses of 50 to 100 ug, implants of gelatin in Sprague-Dawley recipients are rapidly resorbed by a lymphocyte-plasma eel 1-macrophage infiltrate without developing any new bone. With 10 to 20 μg, infiltrate appears and bone develops inversely in proportion to the dose. Bone develops at all dose levels only when bone matrix gelatin and glycopeptide were prepared from an inbred strain of Lewis rats and recipients were of the same strain, and thereby suggests that only allogeneic AHG, produces an antigenic antimorphogenetic...

Silver halide photographic materials with surface layers comprising both alkali and acid produced gelatin

Abstract: Silver halide photographic sensitive materials which comprise a surface layer containing acid treated gelatin and alkali treated gelatin, wherein the ratio by weight of the alkali treated gelatin to the acid treated gelatin is about 0.5 to less than about 100%.

Gelatin manufacture-peroxide liquefaction process

Abstract: Gelatin is extracted from collagen-containing substances by liquefaction with hydrogen peroxide as the sole lyotropic agent. Collagen-bearing tissue is liquefied through agitation with hydrogen peroxide at about 45°-60° C. for from about 4 to about 24 hours at concentrations such that the weight of peroxide is from about 1/3 to 3 times the weight of collagen protein within the system. The thus formed colloidal solution gels upon cooling, and gelatin degradation is minimized by removing peroxide from the solution before the gelatin is dried.

The Lability of Aldimine Crosslinks on Dissolution of Chicken Bone Collagen by Protein Denaturants

Abstract: Bone collagen is highly insoluble in dilute solutions of salt or acid in comparison to the collagens of most unmineralized connective tissues. However, it has been shown that a large proportion of collagen in demineralized chicken bone can be solubilized as gelatin by protein denaturants such as LiC1, KCNS, CaC12, guanidine HC1 or guanidine thiocyanate (GLIMCHER and KATZ, 1965; EYRE and GLIMCHER, 1972). It was thought that the extraction of the collagen was mediated by the rupture of certain crosslinking bonds that were peculiar to the bone collagen and were responsible for its extreme insolubility in non-denaturing solvents. It has been suggested however that the bone gelatin that was extracted from chicken bone by guanidine HC1 may be extensively degraded, presumably by cleavage of peptide bonds (MILLER et al., 1967; PIEZ, 1968).

A process for hardening gelatin

Abstract: A process for hardening, e.g., gelatin, in particular, a gelatin used for photographic light-sensitive materials, which comprises treating gelatin, a non-gelatin hydrophilic high molecular weight material containing primary or secondary amino groups or a composition containing the same with a compound represented by the following general formula (I): ##STR1## WHEREIN R 1 and R 2 , which may be the same or different, each represents a monovalent residue which is bonded through a carbon atom or a sulfur atom thereof to the nitrogen atom forming the carboxylic acid ester, and R 1 and R 2 may combine to form a ring structure; R is a divalent or trivalent residue which is bonded through a carbon atom or a nitrogen atom thereof to the carbon atom of the carboxyl group in the carboxylic acid ester, and n is 2 when R is a divalent residue and n is 3 when R is a trivalent residue.

Pharmaceutical suspension for opaqing empty gelatin capsules

Abstract: A pharmaceutical suspension of titanium dioxide for use in admixing with gelatin solutions for the manufacture of empty opaque gelatin capsules is provided which comprises: titanium dioxide, glycerin, sodium lauryl sulfate, simethicone, sodium citrate and water. A process is also provided which entails the requirement for adding the sodium citrate as the final ingredient in the suspension.

Process for producing edible granules

Abstract: An aqueous solution of edible gelatin, which contains food proteins, is added dropwise to edible oil in such a way that granules form. These are washed with water and given a solid coat by treatment with an aqueous solution of vegetable tannins. The coat formed is reinforced by treatment with a solution of trivalent iron salts of a physiologically tolerated acid and an aqueous solution of acidic polysaccharides. The granular product is thermally stable up to temperatures of 50 DEG C. Appropriate secondary treatment can result in the product being similar to genuine caviar with respect to flavour and aroma.

Process for crosslinking hydrophilic colloids with triazine compounds

Abstract: The present invention relates to a process for crosslinking hydrophilic materials by means of a triazine compound of the formula ##STR1## The process is preferably used for crosslinking gelatin in photographic material.

The rheological properties of solutions and gels of gelatin in different solvents

Abstract: A systematic study was made of the rheological properties of gelatin solutions and gels on replacing the solvent water by DMSO and formamide. A marked change in the character of the systems examined took place and in increase in their high elasticity was observed, the latter being due to changes in the nature of the bonds in the spatial network, and to changes in the conformations of the macromolecules. Contrary to statements published in literature, the results of these investigations show that the elastic modulus is largely determined by the type of solvent used in the case of gelatin solutions.

Nongelling Components from Gelatin Gels: Extraction and Identification

Abstract: Appreciable fractions of gelatin are. found to pcrsist in a mobilc, sol phase whcn rigid gels are examined by scd,mcntatlon (Johnson and Metcalfe, 1967) and, as In thc prescnt study, by proton magnctic rcsonance and extraction mcthods. Aqueous cxtractions on thin layer~ of 4 per cenl gels have pcrmilled isolation of thc sol fraction. This frnclion, at a given Icmperature bclow the melung Point, IS hown (by muluplc gcl-extract-melt cycles) to consist of a significant weight fraction (10 per cent or greater at 18°C, dependll1g upon the gelatin source). Amino aCid analyses provide strong cvidence that the sol fraction consists mainly of α2 chains or fragmcnts thcreof. A value of Mw≈-3 . 104 was found for the sol fraction isolated in this study.

Oil contg. microcapsules by coacervation - in a gelatin and gum arabic soln. contg. thixotropic agent

Abstract: The prodn. of oil-contg. microcapsules by coacervation in a mixed soln. of gelatin and gum arabic is carried out in the presence of a thixotropic agent. The latter remains in the liq. medium throughout the process. The process is esp. useful for the prodn. of pressure-sensitive copying materials. The thixotropic agent prevents excessive aggregation of the microcapsules. The thixotropic agent is pref. a polysaccharide, e.g. "Keltrol" or "Kelzan". It should be used in an amt. of >=4 wt.% based on gelatin.

Process for production of micro capsules containing oily liquid

Abstract: PURPOSE:To produce micro capsules by using phase-separation phenomenon of gelatin and phytin acid and/or alkali, alkaline earth metals in water.

Subcutaneous secretin in dogs: influence of solvent and volume of solvent.

Abstract: Pancreatic secretion in response to subcutaneously injected secretin was studied in three dogs with chronic pancreatic and gastric fistulas. Three solvents: saline, gelatin, carboxymethylcellulose (CMC); two volumes of solvent: 2 and 6 ml; and two doses of secretin: 75 and 150 clinical units were tested. Gelatin was more effective than CMC in prolonging the action of secretin; the duration of the plateau of secretion was about twice as long with gelatin as with saline. Increasing the volume of solvent from 2 to 6 ml also increased the total duration of secretion and total HCO-3 output. It is concluded that gelatin is a suitable vehicle for prolonging the action of secretin.