Showing papers on "Gelatin published in 1993"

Gels and gelling of globular proteins

Abstract: Food gels have many useful properties. Globular protein gels are more nutritious than polysaccharide gels, but most are not as transparent as agarose or gelatin gels. However, by controlling the pH, ionic strength and heating procedure, it is possible to obtain desirable transparent gels from solutions of globular proteins, currently an unused source. The transparent protein gels are interesting substances in which beat-denatured proteins appear to form highly ordered linear polymers.

A new type of biomaterial for artificial skin: Dehydrothermally cross-linked composites of fibrillar and denatured collagens

Abstract: A new type of biomaterial for artificial skin was developed as a form of sponge by combining fibrillar collagen (F-collagen) with gelatin. The sponge was physically and metabolically stabilized by introducing dehydrothermal cross links. To get the final product, various conditions in the preparation of sponges were evaluated by in vitro cellular responses and in vivo tissue reactions. Fibroblasts placed on a sponge of gelatin attached themselves to it, migrated well into the sponge, and remained inside it for at least 7 days. However, sponges of gelatin showed structural instability for hydrolytic degradation by the cells. Most fibroblasts appeared not to penetrate into the interior of a sponge of F-collagen but to remain on its surface when fibroblasts were placed on the sponge, suggesting poor attraction of F-collagen toward cells. Implantation experiments of sponges of F-collagen revealed an intense infiltration of neutrophils into the sponge, indicating F-collagen as an inducer of the inflammatory reaction. These aggravating characters of F-collagen sponges were greatly improved by blending gelatin with F-collagen. The new type of collagen-based biomaterials developed in the present study is expected to become a useful matrix substance for artificial skin.

Pharmaceutical and other dosage forms

Abstract: A fast dissolving, solid dosage form defined by a matrix containing gelatin, pectin and/or soy fiber protein and one or more amino acids having from about 2 to 12 carbon atoms.

Polyanhydride microspheres that display near-constant release of water-soluble model drug compounds

Abstract: A new method to prepare polyanhydride microspheres capable of near-constant sustained release of low molecular weight, water-soluble molecules is presented. The polyanhydrides used were poly-(fatty acid dimer) (PFAD), poly(sebacic acid) (PSA), and their co-polymers [P(FAD-SA)]. Acid orange 63 (AO), acid red 8 (AR), and p-nitroaniline, were used as model release molecules. P(FAD-SA) microspheres containing the molecules with or without gelatin were prepared by a modified solvent evaporation method using a double emulsion. The microspheres were spherical with diameters of 50–125 µm and encapsulated more than 85% of the molecule, irrespective of the compound used. Near-zero-order degradation kinetics were observed for 5 days as judged by sebacic acid (SA) release. Microsphere degradation was pH sensitive, being enhanced at high pH, and became more stable in acidic conditions, irrespective of the incorporation of gelatin in the matrix. For the gelatin-free microspheres, a close correlation of SA release and AO release was observed (2% loading), suggesting a release mechanism that was controlled dominantly by degradation. However, the incorporation of gelatin into the microsphere significantly extended the periods of molecule release from P(FAD-SA) microspheres, although the degradation profile of the microspheres themselves was quite similar to that of gelatin-free microspheres. It is possible that an interaction between FAD monomers and gelatin molecules causes continued release, even after the polymer matrix completely degrades (even after complete degradation, FAD monomers remain because of their poor water solubility). Thermal analysis of polyanhydride microspheres at different degradation stages demonstrated that a crystalline structure was formed between gelatin and the FAD monomers produced with microsphere degradation. This gelatin effect on the extended period of drug release was not observed for microspheres prepared from other polyanhydrides: poly (sebacic acid) and its co-polymer of bis(p-carboxyphenoxy) propane and sebacic acid. It is therefore likely that the crystalline structure formed between gelatin and FAD monomers may function as a reservoir for water-soluble drugs, leading to an extended period of molecule release from the gelatin-loaded P(FAD-SA) microspheres.

Shaped articles containing plant extract(s), in particular pellets, and their pharmaceutical or cosmetic use

Abstract: Shaped articles containing plant extract(s), in particular pellets, are formed by dispersing the plant extract(s) in a matrix predominantly composed of a skeleton builder, i.e. collagen, gelatin, fractionated gelatin, a collagen hydrolysate, a gelatin derivative, plant protein or plant protein hydrolysate. They are storage-stable, and their pharmacological and cosmetic characteristics are essentially unaltered in comparison with the native extract. They are prepared by a simple process in which liquid plant extract(s) is(are) mixed or emulsified in a solution of the skeleton builder, or solid extracts are dissolved or suspended in a solution of the skeleton builder, the dispersion of skeleton builder and plant extract(s) is added dropwise to an intensely cold, inert, liquefied gas, preferably liquid nitrogen, thus shaping the pellets, and the shaped pellets are dried. The plant extract employed is preferably Aloe vera juice.

Controlled release microcapsules

Abstract: Microcapsules are prepared by encapsulating a core material with a capsule shell wall containing glutaraldehyde crosslinked gelatin and at least one water soluble plasticizer that reduces the permeability of the crosslinked gelatin Optionally, the capsule shell wall also contains a feeding deterrent that dissuades accidental ingestion of the microcapsule Upon exposing the microcapsules to water, the plasticizer is removed making the shell wall permeable whereby the encapsulated core material is released Materials such as insecticides, herbicides, plant growth regulating agents, and fungicides may be encapsulated and released at a controlled location, time and rate

Deep-frozen, pre-proofed doughs

Abstract: The invention concerns with deep frozen, pre-proofed doughs that contain 0.5-10 wt % of a gelatin relating compound, optionally in combination with other dough improvers like ascorbic acid, vital gluten, xylanase, amylase or DATA-esters. In particular the combination with xylanase/amylase leads to unexpected results (s.v. and/or ovenspring of baked products made from the doughs). As gelatin relating compounds gelatin, hydrolysed gelatin, collagen hydrolysate and/or gelatin precursors can be used.

A biodegradable tgf-beta delivery system for bone regeneration

Abstract: A biodedegradable composition for the con- troled release of TGF-β is described. This composition is very useful for the delivery of TGF-β in the regeneration of bone. The composition contains, among other components, demineralized bone matrix and a degradable homopolymer or copolymer such as poly (lactic-co-glycolic acid). An implantable delivery system for TGF-β release in a predictable and controlled manner with time is described in which an implantable support is formed or coated with this biodegradable composition. TGF-β is stabilized in a composition contains an organic acid buffer, and to which additional components such as mannitol, human serum albumin, gelatin and/or a non-ionic detergent have been added.

Enhanced solubility pharmaceutical solutions

Abstract: Pharmaceutically acceptable solutions of acidic, basic or amphoteric pharmaceutical agents are disclosed. These solutions are suitable for encapsulation in gelatin capsules for subsequent oral administration and include the pharmaceutical agent, an ion species and a solvent system.

Encapsulation apparatus and process

Abstract: A continuous solvent free gelatin encapsulation apparatus and process includes an oil roll bank assembly (20) for applying a controlled amount of a food-approved lubricant to a first side of the gelatin ribbon and an applicator guide bar assembly (40) for applying a controlled amount of food-approved lubricant to a second side of the gelatin ribbon. Two opposing food-approved lubricant coated gelatin ribbons are then united in a die assembly (50) to form gelatin capsules which are then dried and recovered.

Measurement of Temperature-dependent Ice Fraction in Frozen Foods

Abstract: Ice fraction was measured for solutions containing glucose, sucrose, gelatin, and egg albumin at various concentrations at temperatures from 0 to -20°C. For glucose and sucrose solutions, the ice fraction was accurately measured from phase diagram, which could be interpreted by solution thermodynamics with two parameters. The ice fractions of these sample solutions increased with decreases in both temperature and concentration. Because of the limited applicability of the phase diagram method only to systems with low molecular weight materials, the DSC method was also used for ice fraction measurement. The DSC method, corrected for temperature-dependent latent heat of ice and corrected with Pham’s equation, provided a good approximation for ice fractions with general applicability. The DSC method was used to measure the ice fractions of gelatin and egg albumin gels as a function of solute concentration. The freezing point and bound water of gelatin and egg albumin gels were described as a function of conce...

Caplets with gelatin cover and process for making same

Abstract: Disclosed is a novel simulated capsule medicament consisting of a solid core covered with two shrink-wrapped, hard-shell gelatin capsule halves. The solid cores are covered with the hard-shell gelatin capsule halves by individually shrink-wrapping onto first one end of the core a first hard-shell gelatin capsule half and then individually shrink-wrapping onto a second end of the core a second hard-shell gelatin capsule half.

Expendable Core for Casting Processes

Abstract: A method is provided for forming a sand core which is suitable for use in casting processes, and in particular squeeze casting processes, to form internal features and intricate external features of a cast article. The core forming method involves the use of a single-component gelatin binder whose degradation at elevated temperatures is catalyzed by additions of a ferric compound. The gelatin binder is a mixture of proteins derived from amino acids such as glycine, L-proline, alanine, L-glutamic acid, L-aspartic acid, and/or small percentages of others, such that the gelatin binder is water soluble and therefore easily eliminated from the core sand at the end of the casting process. Due in particular to the presence of the ferric compound, the gelatin binder readily degrades at low temperatures, such as those associated with aluminium casting processes, such that the core degrades sufficiently to permit the sand to freely flow from the cast article without the need for core removal operations. Finally, the gelatin-based binder is nontoxic, such that its elimination from the sand to reclaim the sand for reuse does not pose an environmental hazard.

Purification and characterization of a protease from Porphyromonas gingivalis capable of degrading salt-solubilized collagen.

Abstract: An enzyme capable of hydrolyzing the substrate 4-phenylazobenzyloxycarbonyl-L-prolyl-leucyl-glycyl-prolyl-D-ar gin ine (pZ-peptide), pZ-peptidase, was purified from the oral bacterium Porphyromonas gingivalis. pZ-peptidase hydrolyzed salt-solubilized type I collagen from rat skin, rat plasma low-molecular-weight kininogen, and transferrin at room temperature in the presence of calcium and dithiothreitol. pZ-peptidase did not cleave acid-soluble type I calf skin collagen, type V placental collagen, lysozyme, albumin, or human plasma fibrinogen. Furthermore, the purified enzyme did not hydrolyze N-alpha-benzoyl-DL-Arg-p-nitroanilide, Gly-Pro-p-nitroanilide, N-p-tosyl-Gly-Pro-Arg-p-nitroanilide, N-p-tosyl-Gly-Pro-Lys-p-nitroanilide, azoalbumin, or azocasein. Under reducing conditions, the native enzyme migrated as a single band at 120 kDa on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. However, when heated to 100 degrees C for 10 min in SDS under reducing conditions, the enzyme migrated as a major band at 50 kDa and a minor band at 60 kDa on SDS-polyacrylamide gel electrophoresis. Zymography using calf skin gelatin revealed the gelatin-cleaving activity of the enzyme as evidenced by a diffuse band in the range of 120 to 300 kDa under reducing conditions at room temperature, suggesting that this is the native form of the enzyme. However, incubation at 50 degrees C for 10 min under reducing conditions showed gelatin-cleaving activity at a distinct band of 60 kDa. A minimum temperature of 50 degrees C was required to dissociate the 60-kDa chain from the native complex in active form on gelatin zymography. The ability of the enzyme to cleave other proteins, including kininogen and transferrin, suggests that it has specificity for the Pro-X-Gly sequence found in several proteins, including collagen.

Functional methionines in the collagen/gelatin binding domain of plasma fibronectin: effects of chemical modification by chloramine T.

Abstract: Chemical modification of plasma fibronectin (pFn) or its 40-kDa collagen/gelatin binding (CGB) domain by low concentrations of chloramine T (CT), a methionine-specific oxidant, caused decreased binding affinity between pFn or the isolated CGB domain and Sepharose-immobilized denatured collagen or a Texas Red-labeled CNBr fragment CB7 from the alpha 1 chain of type I collagen. Kds obtained by fluid-phase fluorescence polarization binding assays increased upon oxidation about 17-fold for pFn and by 4-fold for the CGB domain. Comparison of CT-oxidized and native CGB domains by endogenous tryptophan fluorescence and CD spectra gave no indication of conformational changes. delta GH2O, the free energy of unfolding at infinite denaturant dilution, derived from guanidinium chloride denaturation curves, differed by less than 0.7 kcal/mol for the oxidized and native CGB domains, indicating essentially equivalent conformational stabilities. We show here that methionyl residues found at positions 412, 432, and 446 are the sites of the oxidative modification. Modification protection experiments carried out in the presence of gelatin demonstrated specific protection of otherwise oxidizable methionyl residues and preservation of high-affinity binding. These results implicate methionyl residues as functional in contributing to high-affinity binding interaction between fibronectin and gelatin.

The attachment, spreading and growth of baby hamster kidney cells on collagen, chemically modified collagen and collagen-composite substrata

Abstract: Various replicates of collagen substrata were prepared to study the attachment, growth and spreading of baby hamster kidney (BHK) cells. Cell attachment was measured in both the presence and absence of serum. Spreading and growth did not occur in the absence of serum. Attachment to fibrous collagen was less than that found with glass, rat-tail tendon collagen or films prepared from pepsin-solubilized collagen (PS-collagen). Incorporation of hyaluronate, heparin and protamine sulphate into the fibrous collagen and the acetylation of fibrous collagen had little effect. However, incorporation of chondroitin sulphate or chemical modification of fibrous collagen by either methylation or succinylation increased BHK cell attachment. In the absence of serum, the attachment to collagen, acetylated collagen and collagen composites was reduced. The reduction in attachment was marked with fibrous collagen and gelatin films, but less so with collagen composites, acetylated collagen, rat-tail tendon and PS-collagen films. Interestingly, attachment to succinylated collagen and methylated collagen was largely unaffected by the absence of serum, and possible reasons for this are discussed. Cell shape measurements showed decreased spreading of BHK cells on chemically modified collagen films, especially on gelatin films and dried PS-collagen gels. Cell shape and spreading on PS-collagen, rat-tail tendon collagen and collagen-composite films was found to be similar to that on fibrous collagen. BHK cell growth on fibrous collagen, chemically modified collagens, collagen composites, rat-tail tendon and PS-collagen films was similar to that found on plastic tissue culture substrate. Denaturation of fibrous collagen resulted in decreased growth, and BHK cell growth was markedly reduced on PS-collagen gels and dried gels.