Showing papers on "Gelatin published in 1981"

Metalloproteinases from rabbit bone culture medium degrade types IV and V collagens, laminin and fibronectin

Abstract: Gel-filtration chromatography of culture medium from rabbit bone explants separates three latent metalloproteinases with activities against collagen, proteoglycan and gelatin respectively. The fractions degrading proteoglycan also degrade laminin, fibronectin and the polymeric products of pepsin-solubilized type IV collagen and can also solubilize insoluble type IV collagen. The fractions degrading gelatin are capable of degrading solubilized type V and 1 alpha,2 alpha,3 alpha (cartilage) collagens, as well as the lower-molecular-weight products of pepsin-solubilized type IV collagen. All activities can be inhibited by 1,10-phenanthroline and occur in either partially or totally latent forms that can be activated by 4-aminophenylmercuric acetate.

Investigation into the ageing process in gels of gelatin/water systems by the measurement of their dynamic moduli

Abstract: During the ageing (renaturation) process of 1–5% aqueous gelatin solutions the dynamic moduli were measured in the temperature range from −1.2 °C to 25.2 °C. The renaturation process appears to be strongly dependent on concentration, temperature and thermal history. The process at 25.2 °C appears to be of 3rd order, whereas the rate determining step appears to be the aggregation of mono helices into triple helices.

Microcapsules with a defined opening temperature, a process for their production and their use

Abstract: Microcapsules having a defined release temperature and being formed of gelatin or a mixture of gelatin with gum arabic, carboxymethylcellulose and/or anionic polymers, the gelatin having been hardened with a natural and/or synthetic tanning agent and with a carbonyl compound, and the process for making said microcapsules.

Gelatin-based sprayable foam as a skin substitute.

Abstract: Physical and antimicrobial properties of a newly developed gelatin based spray-on foam bandage for use on skin wounds have been evaluated. The aqueous foam is sprayed from aerosol containers and effectively covers and washes uneven wound surfaces. The foam dries to form an adherent and stable three-dimensional matrix which diminishes evaporative water losses. The foam possesses antimicrobial activity against gram-positive, gram-negative, and fungal contaminants.

Composite material of de-N-acetylated chitin and fibrous collagen

Abstract: A composite material of de-N-acetylated chitin and fibrous collagen, which may be prepared by bringing the de-N-acetylated chitin and the fibrous collagen into mutual contact in an aqueous acidic medium followed by deacidifying the obtained product, the fibrous collagen being able to be partially replaced by gelatin and/or soluble collagen, and a shaped material derived from the composite material is excellent in mechanical strength, heat-resistance and biostability and advantageously employed in the field of medical materials, edibles such as edible casing and base materials for inmobilizing enzyme.

Mechanical spectroscopy of filled gelatin gels

Abstract: Small deformation mechanical measurements were performed on the model system of glass filled gelatin gels. By using well characterised samples of glass spheres, rods and irregular pieces of intermediate shape, e.g. plates at varying phase volume of filler, the effect of size, shape and phase volume on the shear storage and loss moduli could be investigated.

Chemiluminescence by polymorphonuclear leukocytes adhering to surfaces.

Abstract: Stimulation of the plasma membranes of granulocytes results in an oxidative metabolic response. This response can be measured by measuring the reduction of oxidizable substrates, such as Nitro Blue Tetrazolium, as well as by measuring the energy released as light (chemiluminescence). While investigating the oxidative response of human granulocytes, we observed a marked variation in the chemiluminescence response when leukocytes were suspended in a balanced salt solution without gelatin or any other protein. We performed systematic study to investigate the role of protein in suspensions of human polymorphonuclear leukocytes. Final results were identical with human serum, albumin, fetal calf serum, and gelatin; gelatin was used as the protein source in most experiments. Polymorphonuclear leukocytes suspended in Hanks balanced salt solution without gelatin decreased in numbers during incubation at room temperature (approximately 50 percent after 60 min). Cell structures were observed on the walls of the tubes containing leukocyte suspensions without gelatin. Numbers of polymorphonuclear leukocytes were stable in suspensions containing gelatin. A chemiluminescence response which peaked at approximately 10 min and was sustained for at least 30 min was observed in suspensions of polymorphonuclear leukocytes without gelatin. This surface attachment-stimulated chemiluminescence occurred in the absence of either soluble or particulate stimuli. Chemiluminescence was inhibited by either superoxide dismutase or sodium azide and did not occur with suspensions of granulocytes from patients with chronic granulomatous disease. We postulate that both superoxide- and myeloperoxidase-dependent oxidative metabolic reactions are induced during the adherence of polymorphonuclear leukocytes to surfaces. Gelatin or other proteins in leukocyte suspending media are necessary when assays are performed to evaluate the metabolic responses of these cells to particulate or soluble stimuli.

Proteinaceous Surfactants Produced from Gelatin by Enzymatic Modification: Evaluation for Their Functionality

Abstract: Proteinaceous surfactants were prepared by applying the “one-step process” which permitted covalent incorporation of amino acid esters directly into proteins during treatment with papain. Gelatin was used as a hydrophile and n-alkyl esters of L-leucine as lipophiles. Each of the hydrophile-lipophile mixtures was incubated with papain under the following conditions: medium, 1M carbonate (pH 9) or a 20:80 mixture of acetone-1M carbonate (pH 9) containing 2 mM 2-mercaptoethanol; concentration of gelatin in the medium, 33% (w/w); L-leucine ester vs gelatin ratio, 0.1 mole/100g; papain vs gelatin, 1% (w/w); incubation period, 15 min; and temperature, 37°C. The enzymatic reaction was stopped by adding 1N HCl and the product purified by dialysis followed by washing with hot acetone or dichloromethane to remove low-molecular species. Each product was found to be a mixture of peptides having a wide range of molecular weight, with an average at approximately 7,500 daltons. The amounts of the alkyl moieties covalently incorporated were in a range 1.1–1.2 moles per 7,500g of the products. Their surfactancy varied depending particularly on the carbon number of the alkyl moiety; the products resulting from the incorporation of C4–C6 alkyl esters of leucine showed greater whippability, whereas the incorporation of the C10–C12 alkyl esters gave products having a higher ability to stabilize an o/w type emulsions.

Preservation and transportation of bacteria by a simple gelatin disk method.

Abstract: A wide range of bacterial species, e.g., Enterobacteriaceae and Neisseria, Streptococcus, Branhamella, Haemophilus, Gemella, Pseudomonas, Flavobacterium, and Bacteroides species, were successfully preserved for 1 to 5 years by our gelatin disk drying method. The beta-lactamase activity of penicillinase-producing Neisseria gonorrhoeae was retained for more than 3 years with this method. Good results were also obtained upon airmailing many strains of N. gonorrhoeae embedded in gelatin disks from Japan to the United States. Neisseria, Branhamella, Gemella, and Haemophilus organisms suspended in the reagent used in the preparation of the gelatin disks could be preserved for 6 to 12 months after freezing the cell suspensions at -20 degrees C. Furthermore, modification of our gelatin disk preservation method made possible the safe long- and short-distance transportation of clinical isolates. Our methods can be used by any small laboratory, since they require only conventional instruments and reagents.

Process for fabricating stable holograms

Abstract: An improved method for fabricating a light weight dichromated gelatin hologram package on plastic or glass substrates is provided. The prior art cover plate protecting the gelatin layer is eliminated by depositing on the gelatin a material providing a barrier to atmospheric moisture and possessing abrasion-resistant properties. In one embodiment, the photosensitive gelatin layer is deposited on a plastic substrate employing at least one subbing layer which provides a barrier to atmospheric moisture. Protection of the gelatin layer is provided by a plasma deposited silicon nitride film thereon.

Proteinaceous Surfactants Produced from Gelatin by Enzymatic Modification: Application to Preparation of Food Items

Abstract: Proteinaceous surfactants produced from gelatin by papain-catalyzed incorporation of L-leucine n-alkyl esters were used as ingredients replacing conventional surfactants for food use. The incorporation of leucine Cz-C6 alkyl esters gave surfactants effective in making snow jelly. In ice cream making, a leucine C12 alkyl ester-incorporated product used as the surfactant gave a high degree of overrun even in a few minutes from the start of whipping. This surfactant was applicable also to making mayonnaise, with formation of a tine emulsion having favorable hardness and adhesiveness. In bread making as well, the same surfactant was usable and found preferable to monostearin. The use of this surfactant resulted in satisfactory loaf quality as well as slow staling of bread over a long period of storage.

Influence of Gelatin on Bioassayable and Immunoreactive Opsonic Fibronectin

Abstract: Plasma fibronectin has a high affinity for denatured collagen (gelatin) and exerts an opsonic influence on phagocytosis of test colloids and clearance of tissue debris by macrophages. This study evaluated the effect of in vitro and in vivo interaction of gelatin with plasma on measurable bioassayable opsonic activity and immunoreactive fibronectin. Incubation of human, dog, sheep, and rat plasma with gelatin prior to in vitro assay decreased (P less than 0.05) the ability of plasma to augment particle uptake in the liver slice bioassay. Incubation of plasma with gelatin also decreased the concentration of fibronectin that could be detected by electroimmunoassay. Intravenous infusion of gelatin into rats, dogs, and sheep resulted in an acute depression in both bioassayable and immunoreactive opsonic observations suggest that deficits of opsonic fibronectin as documented in injured patients by bioassay and electroimmunoassay may not be exclusively related to actual depletion of fibronectin from blood but may be, in part, due to binding of fibronectin to blood-borne material post-trauma, i.e., collagenous tissue debris, whose presence in plasma may limit its detection by both assays.

Carbopol-Gelatin Coacervation: Influence op Some Variables

Abstract: The extent and integrity of microencapsulation is hypothesized to be dependent on the optimization of sediment weight and volume. This led to the investigation of the effects of the type of gelatin or carbopol, the ratios of the coacervate materials, the total colloid concentrations, the starting pH of gelatin sol and the stirring rate. Investigation showed that gelatin, type A, at pH 6.8 together with carbopol 941 gave best results. Optimum carbopol-gelatin ratio was found to be 1/10, above which the sediment weight and volume decreased significantly. Increase in the total colloid concentration results in a parallel increase in sediment weight till concentration of 1.1% w/v above which the increase in sediment weight was less pronounced. A stirring rate of 300-350 r.p.m. gave an almost spherical, uniform coacervates with average diameter of 59u.

Stabilized fruit suspensions and method for preparing the same

Abstract: A fruit suspension which contains a mixture of from 70% to 30% low methoxyl pectin and from 30% to 70% xanthan based on the total weight of gum added, preferably a 50:50 mixture, is effectively stabilized. Such a mixture is particularly useful in stabilizing the fruit suspension employed in sundae style yogurts because it eliminates problems with unwanted gelatin and fruit float.

Process for the preparation and purification of gelatin and pyrogen-free gelatin so prepared

Abstract: A process of preparing an essentially pyrogen-free gelatin solution from cattle hides and/or tanner's stock is described. The essentially pyrogen-free gelatin solution and the use of the pyrogen-free gelatin solution for various pharmaceutical, surgical and medical uses are also described.

Composite material of de-n-acetylated chitin and fibrous collagen, its production and use

Abstract: Problems with conventional collagen materials such as insufficient strength are overcome by a composite material of de-N-acetylated chitin and fibrous collagen. This material may be prepared by bringing the de-N-acetylated chitin and the fibrous collagen into mutual contact in an aqueous acidic medium followed by deacidifying the product obtained. The fibrous collagen can be partially replaced by gelatin and/or soluble collagen. The composite material finds use in medical materials, as an edible casing for food and as a base material for immobilizing an enzyme.

Lyophilized hydrocolloid foam

Abstract: A lyophilized foam sponge product having medically useful hemostatic and adhesive properties formed from the hydrocolloids, gelatin, -pectin, and sodium carboxymethylcellulose and having a density of from about 001 to about 010 grams/cc The gelatin is present at from about 20% to about 80% by weight of the final product and the pectin and sodium carboxymethylcellulose are each present at from about 10% to about 50% by weight of the final product The product is prepared by forming an aqueous colloidal dispersion of hydrocolloids, aerating or foaming, freezing, and lyophilizing

Collagen wound dressing

Abstract: Collagen wound dressing characterized in that it contains collagen in combination with a resorbable biopolymer from the group fibrinogen, SH groups modified gelatin, SH groups modified collagen or SH groups modified regenerated oxycellulose. This collagen wound dressing can be glued to the tissue and does not show the disadvantages of the known fibrin adhesive in combination with resorbable collagen.

Enhancement of recovery of Neisseria meningitidis by gelatin in blood culture media.

Abstract: The efficacy of gelatin for the recovery of Neisseria meningitidis from blood cultures was evaluated in a clinical setting. The organism was isolated from seven patients with meningococcal infections in blood culture media containing 1% gelatin. In contrast, only two blood cultures from these patients were positive in media without gelatin (P less than 0.05). Gelatin did not influence the recovery of other organisms isolated during this study. Conventional blood culture media may be supplemented with gelatin when meningococcemia is suspected.

Non-bitter Protein Hydrolysates

Abstract: Deboned, defatted chicken meat (78% protein, d.b.) was reacted with pancreatin to produce a bitter hydrolysate as judged by a trained sensory panel. The hydrolysis was carried out at 60°C, an enzyme concentration of 4.3%, pH of 8.55 (carbonate buffer) and a salt concentration of 0.6 M (KC1). These conditions resulted in >95% substrate solubility after 120 min. Enzyme activity was monitored by formol titration. Samples for sensory analysis and α amino nitrogen were taken after 0, 30, 60,90 and 120 min and it was found that when chicken alone was reacted with enzyme a steady increase in bitterness was perceived by the panel up to 90 min, reaching a level equivalent in quinine concentration to over .003%. The α amino nitrogen curve was similar in shape to that for bitterness, increasing from about 6 to 23 mg/ g total protein. When gelatin was added (1:1 protein basis, enzyme level constant) the α amino nitrogen curve was not substantially altered but no significant increase in bitterness was perceived. When glycine, which is a sweet amino acid found in large quantities in gelatin, was added to the chicken hydrolysate at the same level that would have been in a chicken: gelatin preparation, it significantly reduced bitterness while proline and hydroxyproline alone did not. It was concluded that the mechanism by which gelatin affects protein hydrolysate may be the ability of the endogenous amino acid glycine to mask bitterness.

Independence of Reciprocal Attachment Sites on Denatured Collagen and Fibronectin from Antigenic Sites, and Binding of Gelatin-based Plasma Substitutes to Plasma Fibronectin

Abstract: Fibronectin and denatured collagen possess attachment sites for each other and, in addition, antigenic sites reacting with the respective antibodies. Using an enzyme linked immunosorbent assay it was shown that attachment sites and antigenic sites on fibronectin and on collagen reacted independently of each other. Gelatin-based plasma substitutes blocked the binding of fibronectin to denatured collagen thus showing that attachment sites for fibronectin are preserved in the gelatin preparations used for manufacturing these plasma substitutes. Antigenic sites, in contrast, were destroyed during the manufacturing process as shown with antibodies to denatured collagen raised in guinea-pigs. It is concluded that complex formation of gelatin-based plasma substitutes with plasma fibronectin may occur upon infusion of such plasma substitutes but that formation of antigen/antibody complexes in vivo is unlikely.

Grafting onto Protein. I. Graft Copolymerization of Poly(methyl Acrylate) onto Gelatin

Abstract: Poly(methyl acrylate) has been graft copolymerized onto a soluble protein, gelatin, in aqueous medium by using eerie amnionic nitrate (CAN) as the redox initiator. Graft copolymerization was carried out at 35, 45, and 55°C for various reaction periods. Maximum percent grafting occurred at 45°C. Nitric acid was found to influence grafting. Percent grafting has been determined as a function of (1) concentration of CAN, monomer, and nitric acid; (2) time; and (3) temperature.

Encapsulation of indomethacin

Abstract: Indomethacin is encapsulated by aqueous gelatin/polysaccharide coacervation by first forming a dispersion or paste of Indomethacin in a water-miscible liquid polyhydroxyalkane. Preferably the coacervate system is gelatin/acacia and the polyhydroxyalkane is glycerol.