EP0845031A1 - Procedes et composes chimiques permettant de modifier des polymeres - Google Patents

Procedes et composes chimiques permettant de modifier des polymeres

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Publication number
EP0845031A1
EP0845031A1 EP96927804A EP96927804A EP0845031A1 EP 0845031 A1 EP0845031 A1 EP 0845031A1 EP 96927804 A EP96927804 A EP 96927804A EP 96927804 A EP96927804 A EP 96927804A EP 0845031 A1 EP0845031 A1 EP 0845031A1
Authority
EP
European Patent Office
Prior art keywords
polymer
protein
effector moiety
paper
improvement
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP96927804A
Other languages
German (de)
English (en)
Inventor
Robert Bates
Stephen David Greenaway
David John Hardman
Margaret Huxley
James Howard Slater
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hercules LLC
Original Assignee
Hercules LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hercules LLC filed Critical Hercules LLC
Publication of EP0845031A1 publication Critical patent/EP0845031A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/20—Macromolecular organic compounds
    • D21H17/21—Macromolecular organic compounds of natural origin; Derivatives thereof
    • D21H17/22—Proteins
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/16—Sizing or water-repelling agents
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/005—Microorganisms or enzymes

Definitions

  • the present invention relates to methods and chemical compounds for modifying the physical properties of a polymer.
  • the present invention relates to methods and chemical compounds for modifying the physical properties of a polymer by binding to the polymer a chemical compound, hereinafter referred to as an "effector moiety", which confers on the polymer improved fluid, electrical or strength properties.
  • Naturally occurring polymers include, for example, proteins (including keratin, which is the principal component of wool) , starch, pectin, guar, chitin, lignin, agar, alginate, and polysaccharides such as cellulose and hemi-celluloses (including xylan, mannose and arabinose) .
  • Cellulose is encountered in the form of, for example, wood fibre and annual crop fibre (for example, hemp, straw, rice, flax, jute) based products such as paper, and cotton, which may be in the form of fibres, yarns, threads or a variety of woven and non-woven textile or fabric products.
  • Xylanose is the principal component of xylan, otherwise known as he i-cellulose which occurs in grasses, cereal, straw, grain husks and wood.
  • Starch occurs in seeds, fruits, leaves, bulbs etc.
  • the physical properties of polymers and materials containing polymers may be modified by a variety of chemical and physical treatments. Such chemical and physical treatments may be directed at modification of the polymer structure itself or at modification of the bulk properties of the material containing the polymer.
  • the bulk properties of a material containing a polymer may, for example, be modified by admixture to the material of agents such as wet strength agents, dry strength agents or other chemical compounds which modify the physical properties of the material. Admixture of such chemical compounds to the material typically does not bind the compounds strongly to the polymer and problems may therefore be experienced with wastage of the chemical compounds and with the compounds leaching out of the material, resulting in variations in the properties of the material.
  • Leaching out of the chemical compound may be reduced by a charge balancing protocol in which the ionic charge of the chemical compound is made equal and opposite to that of the polymer- containing material.
  • the charge on both components varies widely requiring careful and frequent control measures.
  • the modifying effect of the chemical compound may also rely on covalent binding to the polymer in order to properly achieve a modifying effect.
  • promoters may be required to facilitate binding of certain chemicals to the material.
  • the chemical compounds may be applied to the surface of the material by, for example, immersion or printing.
  • the chemical compounds typically do not bind to the surface of the material and problems may be encountered with diffusion of the compounds away from the intended site of application.
  • non-covalent binding interactions are known; for example, the binding interaction between an antibody and an antigen and the binding interaction between biotin and avidin or streptavidin.
  • Enzymes capable of modifying an enzyme substrate also typically rely on a non-covalent binding interaction with the enzyme substrate in order to function.
  • One such class of enzymes comprise enzymes which degrade polymers, for example proteinases, keratinases, chitinases, ligninases, agarases, alginases, xylanases, mannases- amylases, cellulases and he i-cellulases.
  • enzymes which degrade polymers for example proteinases, keratinases, chitinases, ligninases, agarases, alginases, xylanases, mannases- amylases, cellulases and he i-cellulases.
  • cellulases and hemi-cellulases cleave saccharide or polysaccharide molecules from cellulose and hemi-cellulose, respectively, and amylases cleave glucose from starch.
  • binding domains of such proteins can be separated from the active-site domains by proteolysis.
  • the isolated binding domains have been shown to retain binding capabilities (Van Tilbeurgh, et al . , FEBS Letters, 204(2) . 223-227, August 1986).
  • Use of cellulose binding domains of cellulases has been proposed as a means of roughening the texture of the surface of cellulosic support, while use of cellulase active-site domains has been proposed as a means of smoothing the texture of such surfaces (International patent application WO93/05226) .
  • binding domains have also been characterised at the genetic level (Ohmiya et al .,Microbial Utilisation of Renewal Resources, 8., 162-181, 1993) and have been subcloned to produce new fusion proteins (Kilburn et al . , Published International Patent Application WO90/00609; Ong et al . , Enzyme Microb. Technol, H, 59-65, January 1991; Shoseyov et al . , Published International Patent Application
  • fusion proteins have then been used as anchor proteins for specific applications. Such proteins have been used as an aid to protein purification through adhesion of the fusion proteins to cellulosic support materials used in protein purification strategies (Kilburn et al . , United States Patent 5,137,819; Greenwood et al . , Biotechnology and Bioengineering, 4_4, 1295-1305, 1994) .
  • the ability to immobilize fusion proteins onto cellulosic supports has also been suggested as a means of immobilization for enzyme bioreactors (Ong et al . , Bio/Technology, J, 604-607, June 1989; Le et al . Enzyme Microb. Technol., 35, 496-500, June 1994), and as a means of attaching a chemical "tag" to a cellulosic material (International Patent Application 093/21331) .
  • a method of treating a polymer to achieve an improvement in at least one property selected from fluid, electrical and strength properties comprising binding an effector moiety to said polymer via a protein linkage for the purpose of achieving said improvement, said effector moiety being different from said protein linkage and said protein linkage being different from said polymer, said effector moiety and said protein linkage being present in an amount effective to achieve said improvement.
  • the polymer may comprise a polymeric molecule or a polymeric material comprising polymeric molecules.
  • reference to an effector moiety and a protein linkage refers to at least one effector moiety and at least one protein linkage, respectively.
  • the present invention encompasses a method of treating a polymer to achieve an improvement in at least one property selected from fluid, electrical and strength properties comprising binding at least one effector moiety to at least one polymer via at least one protein linkage for the purpose of achieving said improvement, said at least one effector moiety being different from said at least one protein linkage and said at least one protein linkage being different from said at least one polymer, said at least one effector moiety and said at least one protein linkage being present in an amount effective to achieve said improvement.
  • a method of treating a polymer to achieve an improvement in at least one property selected from fluid, electrical and strength properties comprising contacting said polymer with an effector moiety and a protein for the purpose of achieving said improvement, said effector moiety being different from said protein and also different from said polymer, and said protein being different from said polymer, and said effector moiety and said protein being present in an amount effective to achieve said improvement.
  • the invention encompasses a method of treating a polymer to achieve an improvement in at least one property selected from fluid, electrical and strength properties comprising contacting at least one polymer with at least one effector moiety and at least one protein for the purpose of achieving said improvement, said at least one effector moiety being different from said at least one protein and also different from said at least one polymer, and said at least one protein being different from said at least one polymer, and said at least one effector moiety and said at least one protein being present in an amount effective to achieve said improvement.
  • composition of matter comprising a polymer to which is bound an effector moiety via a protein linkage, said effector moiety being different from said protein linkage, wherein said effector moiety and said protein linkage are present in an amount effective to achieve an improvement in at lea ⁇ t one property selected from fluid, electrical and strength properties of said polymer.
  • method of treating paper or the constituent fibres of paper to achieve an improvement in at least one property ⁇ elected from fluid, electrical and strength properties comprising binding at least one effector moiety to said paper or constituent fibres of paper via at least one protein linkage for the purpose of achieving said improvement, said at least one effector moiety being different from said at least one protein linkage and said at least one protein linkage being different from said paper or constituent fibres of paper, and said at least one effector moiety and said at least one protein linkage being present in an amount effective to achieve said improvement.
  • the present invention provides methods and chemical compounds for modifying the fluid, electrical and/or strength properties of a polymer or material containing a polymer by binding to the polymer an effector moiety capable of conferring the desired property.
  • polymer includes reference to materials containing a polymer.
  • the polymer-containing material may consist exclusively of polymer or may comprise polymer in combination with other components.
  • the polymer may comprise any polymer of any number of monomeric units.
  • the polymer comprises a naturally occurring polymer or a chemically modified derivative thereof.
  • the naturally occurring polymer may, for example, comprise a protein such as keratin, or a polysaccharide such as a starch, pectin, guar, chitin, lignin, agar, alginate.
  • the polymer comprises a polysaccharide.
  • the polysaccharide may comprise any polysaccharide, for example, mannose, xylanose, cellulose or a hemi-cellulose, preferably cellulose.
  • Materials comprising cellulose may comprise wood-fibre or annual crop fibre (for example, hemp, straw, rice, flax, jute) based material, such as paper.
  • the material may comprise cotton in the form of fibre, thread or woven or non-woven textile, fabric or cotton-based paper.
  • the material comprises paper.
  • the present invention may be employed to modify any fluid, electrical or strength property of the polymer.
  • Properties of the polymer that may be modified include wet strength and dry strength, sizing, hydrophobicity, dye resistance and stain resistance, fluid penetration, oil and water repellency, electrical conductivity and resistance, electrical capacitance, pH and biometallic properties.
  • the protein employed in the present invention may comprise any protein capable of binding to the polymer.
  • the protein is capable of binding the polymer with a dissociation constant of (Kd) less than 1 x 10 "3 M.
  • the term "protein” includes peptide, oligopeptide and polypeptide, as well as protein residues, protein- containing species, chains of amino acids and molecules containing a peptide linkage. Where the context requires (*.r examnle, when protein is bonded to another molecule). reference to a protein means a protein residue.
  • protein linkage refers to a protein or protein residue via which an effector moiety is bound to a polymer.
  • the protein may comprise a naturally occurring protein, or fragment thereof or modified protein obtainable by chemical modification or synthesis or by expression of a genetically modified gene coding for the protein.
  • modified protein includes chemical analogs of proteins capable of binding to a polymer.
  • proteins capable of binding polymers are well known and include enzymes selected from the group comprising cellulases, hemi-cellulases, mannases, xylanases, proteinases, keratinases, chitinases, ligninases, agarases, algina ⁇ es and amylases.
  • a variety of cellulases are known which are dependent upon binding to cellulose for their activity.
  • cellulases examples include those isolable from bacterial organisms such as Cellulomonas fimi and fungal organisms such as Trichoderma viride, Aspergillus niger, Penicillium funiculosum, Trichoderma reesei and Humicula insolens, available as commercial preparations from Sigma Chemical Sigma-Aldrich Company Ltd., Novo Nordisk A/S, BDH Ltd., or ICN Biomedicals Ltd.
  • the protein may be produced by recombinant DNA techniques as disclosed in, for example, International Patent application W094/24158.
  • Cellulases generally comprise a cellulase binding domain and a domain responsible for cellulase activity.
  • the present invention may employ the cellulase as a whole or a fragment thereof capable of binding to cellulose.
  • a cellulase binding domain may be obtained from whole cellulase by treatment with protease(s), such as papain.
  • the present invention may employ an exo-cellulase or an endo-cellulase.
  • the protein comprises a naturally occurring enzyme which is capable of binding to the polymer. More preferably, in respect of paper, the catalytic activity is deactivated.
  • the catalytic activity of the enzyme may be deactivated by, for example, attachment of the effector moiety or cross-linking of the enzyme.
  • Cross-linking of the enzyme may be achieved with any suitable protein cross ⁇ linking agent such as a dialdehyde such as glutaraldehyde.
  • the protein comprises a deactivated naturally occurring cellulase.
  • the effector moiety may be attached to the protein capable of binding to the polymer in any convenient manner.
  • the effector moiety may be covalently bonded directly to the ' protein, via suitable reactive functional groups in the effector moiety and protein.
  • Recognition of suitable reactive functional groups and, if necessary, their chemical modification to facilitate covalent bonding are within the ability of a person of ordinary skill in the art.
  • Examples of covalent bond formation include formation of an amide bond between a carboxyl group and an amine group, by means of carbodiimide or dimethyl formamide activation of the carboxyl group.
  • the effector moiety may be attached to any suitable part of the polymer binding protein.
  • the effector moiety may be attached to the polymer binding protein at the N-terminal end of the protein, for example via the N-terminal amino group.
  • it may be attached at the C-terminal end of the protein, for example via the C-terminal carboxyl group.
  • the effector moiety may be attached to the protein via an alternative functional group present, for example, in the amino acid chain of the protein or in a side chain thereof or introduced into the protein for the purpose of attachment to the effector moiety.
  • the effector moiety may, for example, be attached via a thiol group present in cysteine, a hydroxyl group present in serine or threonine, an amino group present in lysine or arginine, an amide group present in asparagine or glutamine, a carboxyl group present in aspartic acid or glutamic acid or an aromatic or heteroaromatic group present in phenylalanine, tyrosine, tryptophan or histidine, or derivatives thereof.
  • the effector moiety may be attached to the protein via a linker.
  • the linker may, for example, comprise a difunctional molecule capable of reacting with a reactive site of the protein and a reactive site of the effector moiety so as to link the protein and effector moiety. It may be advantageous to include such a linker as a spacer between the protein and effector moiety, so that the two species are sufficiently spaced apart so as not to interfere sterically with each other's activity. A linker may also be advantageous in providing suitable functional group with which to join the effector moiety and protein.
  • the effector moiety may be attached to the protein via a non-covalent binding pair of molecules.
  • non-covalent binding pairs of molecules include biotin and avidin, streptavidin or neutralite.
  • the effector moiety is covalently attached to streptavidin whilst the polymer binding protein is covalently attached to biotin. Combining these components facilitates binding of the streptavidin and biotin portions of each component and hence attachment of the effector moiety to the polymer binding protein.
  • the effector-streptavidin component may be mixed with the protein-biotin component either before or after the protein component has been bound to the polymer.
  • the effector moiety may be covalently attached to biotin, whilst the protein is covalently attached to avidin, streptavidin, or neutralite.
  • effector moiety may be attached to the polymer. Two or more types of effector moiety may be used in order to reinforce each other's effect or to provide two or more effects simultaneously. It will be appreciated that in general the effector moiety may be attached to the polymer binding protein either before or after the polymer binding protein is bound to the polymer.
  • the method of the present invention may comprise contacting a conjugate of the effector moiety and the protein with the polymer, or may comprise contacting the effector moiety with a comjugate of the protein and polymer. Alternatively, attachment of the effector moiety to the protein and attachment of the protein to the polymer may be accomplished in situ in a one-step process.
  • Binding may be by means of a chemical bond such as a covalent bond or by means of a non-covolent physical interrelation, tie, association, attraction or affinity.
  • the effector moiety may comprise any moiety capable of conferring a desired physical property.
  • the effector moiety may comprise an atom, molecule or chemical compound or residue thereof capable of conferring the desired physical property.
  • the effector moiety comprises a chemical compound capable of conferring a desired physical property.
  • the agent may comprise a wet strength agent such as an aldehyde eg glutaraldehyde or dialdehyde starch or its cationic derivative, polyamide resin, polyacrylamide copolymer glyoxal, glyoxylated polyacrylamide, polyethyleneimine, polyamineepichlorohydrin polymers, polyamidoamine epichlorohydrin polymers, urea formaldehyde and melamine formaldehyde polymers, synthetic latexes, formaldehyde modified proteins or other polymers used for the purpose of imparting wet strength to paper; a dry strength agent such as starch, anionic or cationic starch, polyacrylamide, amphoteric, cationic or anionic polyacrylamide copolymers, anionic or cationic guar, locust bean gum or anionic or cationic modifications thereof.
  • a wet strength agent such as an aldehyde eg glutaraldehyde or dialdehyde starch or
  • an agent capable of conferring electrical conductivity ⁇ uch a ⁇ a metal an agent capable of conferring stiffness; an agent capable of conferring absorbency; an agent capable of conferring hydrophilicity; an agent capable of modifying density; a metallising agent; an agent capable of modifying pH, such as a buffer (for example, to impart resi ⁇ tance to acid degradation) .
  • the effector moiety may comprise a cro ⁇ -linking or matrix forming agent or re ⁇ idue thereof, which may it ⁇ elf ⁇ erve to modify the phy ⁇ ical properties of the polymer, or may serve to modify the properties of the protein and hence the physical properties of the polymer, or may serve to entrap a further agent capable of modifying the physical properties of the polymer.
  • Preferred examples of cross-linking matrix forming agents comprise ⁇ dialdehydes, such as glutaraldehyde. Dialdehyde ⁇ such as glutaraldehyde can for example form a matrix with a cellulase derived protein. The cellulase/glutaraldehyde matrix confers improved wet strength and dry strength on paper, sizes the paper and/or may entrap further agents such a ⁇ Ti0 2 or CaC0 3 .
  • paper refers to any material in the form of a coherent sheet or web, comprising an interlaced network of cellulose containing fibres derived from vegetable source ⁇ optionally mixed with fibre ⁇ from vegetable, mineral, animal or ⁇ ynthetic sources in various proportions and optionally mixed with fine particles of inorganic materials such as oxides, carbonates and sulphates of metallic elements in various proportions.
  • paper includes paperboard which refers to paper when the weight of the paper sheet or web is greater than 200g/m 2 .
  • Vegetable source ⁇ of cellulo ⁇ e include wood, straws, Bagasse, Esparto, bamboo, Kanaf, Grass, Jute, Ramie, Hemp, Cotton, Flax.
  • the crude vegetable derived cellulose is processed to form pulp, the material from which paper is made, either mechanically, chemically or both.
  • Cellulose containing pulps may be described as mechanical, chemimechanical and chemithermomechanical, semi chemical, high yield chemical, full chemical (see “Pulp and Paper, Chemistry and Chemical Technology", Third Edition, Volume 1 pages 164, 165 edited by James P. Cassay ISBN 0-471-03175-5 (v.l)) according to the method of pulp preparation and purification.
  • the effector moiety may be attached to the polymer at any suitable stage in the manufacture and proce ⁇ ing of the polymer or material containing the polymer.
  • the effector moiety i ⁇ to be applied to paper it may be attached at the pulp ⁇ tage or at any ⁇ tage during the formation of the wet pulp matrix or during the pre ⁇ sing and rolling of the matrix to form paper.
  • the effector moiety may be attached to the formed paper product by immersing the paper in a bath containing the reagents for attaching the effector moiety or by any suitable spraying, spreading, brushing, coating or printing process.
  • the effector moiety may again be attached at any stage in the proces ⁇ ing of the cotton fibre. It may be attached to cotton fibre, thread, yarn or to woven or non-woven cotton fabric or textiles.
  • the effector moiety may be attached by immersing the material in a bath containing the reagents for attaching the effector moiety or by any suitable spraying, spreading, brushing, coating or printing process.
  • control may be exercised as to whether the effector moiety is distributed throughout the polymer material or is substantially restricted to the surface levels of the material.
  • the effector moiety In cases where the effector moiety is directed at modifying the bulk propertie ⁇ of the material, it may be advantageous to ensure even distribution of the effector moiety uniformly throughout the material. Accordingly, the effector moiety should be attached at an early stage in the manufacture. For example in the manufacture of paper where the effector moiety is directed at modifying the bulk properties of the paper, the effector moiety should be applied at the pulp stage.
  • the effector moiety In cases where the effector moiety is directed at modifying the surface properties of the material, it may be sufficient to restrict the effector moiety to the surface levels of the material, with an attendant advantage in reducing the quantities of effector moiety required. Accordingly, the effector moiety should preferably be supplied at a late stage in the manufacture. For example, in the manufacture of paper, where the effector moiety is directed at modifying the surface propertie ⁇ of the paper the effector moiety should be applied to the paper ⁇ urface.
  • the effector moiety may be de ⁇ irable to apply the effector moiety to one or both planar surfaces of the paper.
  • Such a structure is capable of transporting liquids through its middle layer by capillary action and is particularly useful in the manufacture of dip- ⁇ tick type diagnostic as ⁇ ay ⁇ .
  • a particular feature of the pre ⁇ ent invention concerns the ability to modify the physical properties of the polymer or material containing the polymer in a reversible manner.
  • Conventional treatment of polymers to impart particular physical propertie ⁇ are often non-rever ⁇ ible.
  • the conventional treatment ⁇ often render the polymer un ⁇ uitable for recycling.
  • the repulping of paper is made more difficult and may be impos ⁇ ible if the paper i ⁇ treated with conventional wet strength agents.
  • the present invention lends itself to the
  • the effector moiety may, for example, be released from the polymer-containing material by treatment with a protease which cleaves the protein attaching the effector moiety to the polymer; alternatively, the effector moiety may be attached to the protein by means of a selectively cleavable linker; cross ⁇ linking agents such a ⁇ aldehyde- ⁇ ub ⁇ tituted ⁇ tarch may be cleaved by amylase.
  • a further advantage of the present invention lies in the fact that the desired physical property is imparted essentially immediately to the material. In conventional , treatments to impart wet strength to paper, heat treatment and curing over several weeks may be required.
  • Figure 1 shows the effect of cellulase concentration on glutaraldehyde cross-linked cellulase imparted wet strength.
  • Figure 2 shows the effect of glutaraldehyde concentration on glutaraldehyde cross-linked cellulase imparted wet strength
  • Figure 3 shows the effect of pH on glutaraldehyde cross ⁇ linked cellulase imparted wet strength
  • Figure 4 show ⁇ the effect of temperature on glutaraldehyde cro ⁇ -linked cellula ⁇ e imparted wet strength
  • Figure 5 hows the effect of incubation time on glutaraldehyde cros ⁇ -linked cellula ⁇ e imparted wet strength
  • Figure 6 shows the effect of pre-incubation time on glutaraldehyde cross-linked cellulase imparted wet strength
  • Figure 7 shows the effect of glutaraldehyde cross-linked cellulase on the wet strength of paper produced from different wood pulp ⁇ .
  • the protocols defined below represent the techniques used to characterize the use of cellulase as a biobridging agent for the attachment of effector moieties to cellulose.
  • Anhydrous materials are not essential but the above mentioned weights should be recalculated to take into account any "water of crystallization" in the hydrated salts.
  • the cellulases that have been used were derived from fungal source ⁇ and are available either as aqueous solution ⁇ or freeze dried powder ⁇ .
  • Cellula ⁇ e derived from Penicillium funiculo ⁇ um (Sigma Aldrich Co. Ltd., Poole, Dorset, U.K.) is available as a tan powder and should be stored at below 0 C.
  • the cellulase When used as an additive for handsheets the cellulase was first be prepared as a 20% total solids solution in 2 / 3 PBS. Into a large shallow beaker was placed 200g of the dry enzyme preparation. To this was then added slowly 800g of 3 PBS. The mixture was gently stirred with a glas ⁇ rod. Vigorous agitation of the solution should NOT be used to disperse the powder as denaturing of the enzyme may occur. Any clumps of enzyme preparation may be broken up gently with the glass rod. If the cellulase solution is prepared the day before use then it should be stored at 4 C.
  • Cellulase derived from Trichoderma Reesei is available either as freeze dried powder from Sigma Aldrich Co. Ltd. Poole, Dorset, U.K. or as an aqueous solution from Novo Nordisk A/S, Bagsvaerd, Denmark. When using the powder, the procedure and handling practi ⁇ es for preparation of the aqueous solution with Penicillium funiculosum apply here as well.
  • the cellulase solution was added to the stock on the basis of the total protein content of the enzyme solution (e.g. 10 parts of dry protein per 100 parts of dry fibre) .
  • cellulose such as microcrystalline cellulose (Avicel, SigmaCell) or water-leaf paper pulp
  • Cellula ⁇ e ⁇ olutions typically containing between 200-600 mg protein ml -1 in 3 ml buffer
  • concentration of protein added was experimentally determined at the start of the binding assay using the assay developed by Sedmak and Grassberg (Analytical Biochemistry, 79., 544-552 (1977)).
  • the tubes were shaken at the desired temperature (typically between 4°C and 30°C but usually at room temperature), for a period of time (typically 1 to 90 min, usually between 5 to 15 min). Samples (0.5 - 1ml) were then taken for assay.
  • sample ⁇ were centrifuged in a 1 ml Eppendorf tube using a bench-top microfuge for 5 min and the supernatant retained for determination of protein concentration remaining in the supernatant (unbound cellula ⁇ e) .
  • the supernatant protein concentration was subtracted from the initial protein concentration thereby defining the amount of cellulase associated with the cellulose pellet.
  • Bovine serum albumin (BSA) was used in the as ⁇ ay as a control.
  • results were presented as either the amount of protein bound to the cellulose as a percentage of the protein added, or as the amount of protein bound to the cellulo ⁇ e a ⁇ a percentage of the protein/cellulo ⁇ e (%w/w) .
  • a solution of biotinamido N-hydrosuccinimide ester (B cap NHS) in N,N-dimethylformamide (DMF) was prepared (1 mg ml -1 ) .
  • a solution of cellulase was prepared in distilled water (77 mg ml -1 ) .
  • a water-leaf paper sheet usually 2 cm 2
  • biotinylated cellulase at a range of concentrations between 0.05 to 100 ⁇ g ml "1 protein in 1/3 PBS (10 ml) for 45 min to 2 h at 4°C in a shallow Petri-dish with shaking.
  • PBS containing Tween 20 (0.1% vv -1 ) were also performed.
  • Paper pulp was incubated with the biotinylated cellulase in 1/3 PBS containing Tween 20 (0.1% vv -1 ) for 45 min at room temperature with shaking.
  • a disc of paper was formed from the paper pulp-biotinylated cellulase using the paper making filter. The paper disc was removed from the filter, rolled and allowed to dry overnight.
  • the paper was incubated with milk powder (4% wv "1 ) in PBS for 45 min at either 4°C or room temperature with shaking to block non-specific binding of the HRP- streptavidin conjugate. The paper was then washed, 3x 3 min, u ⁇ ing 0.5% (wv -1 ) milk powder in 1/3 PBS containing Tween 20 (0.1%vv _1 ). The ⁇ olution was discarded and replaced after each wash.
  • horseradi ⁇ h peroxidase (HRP) - ⁇ treptavidin conjugate was prepared as a 1:1000 part solution using milk powder (0.5% wv -1 ) made up in 1/3 PBS containing Tween 20 (0.1%vv _1 ). A suitable volume (2 to 10 ml) was added to cover the paper sheet which wa ⁇ then incubated for 45 min at room temperature with ⁇ haking.
  • the paper was then washed 3x 5 min, in 1/3 PBS containing milk powder (0.5% wv -1 ) and Tween 20 (0.1%w ⁇ 1 ) . The wa ⁇ h ⁇ olution was discarded and replaced after each wash. The paper was then washed 3x 5 min using 1/3 PBS and again the wash solution was discarded and replaced after each wash.
  • the cellulose bound cellulase-biotin-HRP-streptavidin conjugate was then visuali ⁇ ed by the ECL method or quantified u ⁇ ing the OPD methodology.
  • ECL Enhanced chemiluminescence
  • the paper was incubated for exactly 1 min at room temperature without agitation.
  • the detection reagent was drained off and the paper was blotted between two pieces of tissue paper to remove excess reagent.
  • the blotted paper was then transferred to a piece of cling film and wrapped securely to remove any air pockets.
  • the paper was placed in a film ca ⁇ sette minimising the delay between incubating the paper and exposing it to the Hyperfilm.
  • the film was carefully placed on top of the paper and the film exposed for 15 s ensuring that the film did not move during exposure. This first sheet of film was then removed and immediately replaced with a second film which was then exposed for 1 min.
  • the substrate buffer was prepared by dissolving 1 OPD tablet (60 mg; o-phenylenediamine dihydrochloride, Sigma Chemicals, UK) in 150 ml 0.06 M phosphate-citrate buffer (0.2 M Na 2 HP0 4 , 121.5 ml; 0.1 M citric acid 121.5 ml made up to 500 ml distilled water and the pH adjusted to 5.0) to give a final OPD concentration of 0.4 mg ml. j . Note that thi ⁇ reagent is light sen ⁇ itive. 10 ⁇ l of fresh 30% H 2 0 2 per 25 ml of substrate buffer was added immediately prior to use.
  • the paper samples containing the biotinylated cellulase were placed into a 50 ml Falcon tube. 25 ml of the complete substrate buffer solution was added to the tube and shaken at room temperature for 30 ⁇ to 20 min, and usually between 5 and 15 min, then the reaction was stopped by adding 1 ml of 3M H 2 S0 4 . The absorbence was then determined at 492 nm and reference was made to a standard curve of 0D 49 vs biotinylated cellulase concentration in order to calculate the concentration of biotinylated cellulase present on or in the paper.
  • Carbodiimides react with carboxylate groups to form activated carboxyls. Amino groups then attack these activated carboxyls to form covalent peptide bonds. This chemistry can be used to attach paper effector chemicals which contain free carboxyl groups to the amino groups on peptides.
  • abietic acid was coupled to cellulase.
  • reaction was then stopped by the addition of sodium acetate (0.1 M; pH 5.0) and exces ⁇ abietic acid and WS-CDI was removed by exhaustive dialysi ⁇ in pho ⁇ phate buffer.
  • the coupled cellulase was then used to bridge the abietic acid onto cellulose as described above.
  • Water-leaf paper pulp slurry was produced in the following manner: 10 g water-leaf paper was cut into 1 cm 2 squares and macerated in a domestic herb mill (CH100, Kenwood Ltd. UK) for 3 min with 100 ml distilled water.
  • the volume wa ⁇ increased to 100 ml with distilled water and paper sheets (6 cm 2 ) produced using a laboratory-designed paper making apparatus operated in the following manner: a suspension of paper pulp (0.2% wv -1 ) was poured into a plastic filter holder which houses a fine nylon filter mesh. By applying a vacuum for a few seconds the pulp was formed into a paper ⁇ heet ⁇ upported by the me ⁇ h. The filter me ⁇ h was removed from the apparatus and the paper sheet ⁇ andwiched between a second nylon mesh and blotted between adsorbent paper towel ⁇ . The paper sheet was carefully removed from the paper-making me ⁇ h, flattened by rolling and allowed to dry overnight.
  • the wet-strength of the paper samples were retested to include BSA controls to assess the specificity of action of the bridging protein.
  • the paper samples were prepared a ⁇ follows
  • samples prepared using cross-linked BSA showed an increased wet tensile strength compared to the controls, this was 100 fold less than that of the glutaraldehyde cros ⁇ -linked cellula ⁇ e.
  • cellulase 0.5 to 8 mg ml" 1
  • glutaraldehyde 0.1 to 2.5 vv "1 )
  • pH 5.0 to 10.0
  • temperature 25°, 37° and 45°C
  • incubation time 5 to 120 min
  • time of pre-incubation of the cellulase and glutaraldehyde 15 to 60 min
  • the GCC wet strength composition was applied to paper produced from different types of pulp: ground wood pulp (GWP) , chemo- thermo-mechanical pulp (CTMP) , hard wood pulp (HWP) , soft wood pulp (SWP) and water-leaf pulp (W-LP; 70% HW: 30% SW) .
  • GWP ground wood pulp
  • CTMP chemo- thermo-mechanical pulp
  • HWP hard wood pulp
  • SWP soft wood pulp
  • W-LP water-leaf pulp
  • W-LP water-leaf pulp
  • HWP Buffer ⁇ 5 ⁇ 15.3 Cellulase ⁇ 10 ⁇ 15.3 Glutaraldehyde ⁇ 10 ⁇ 15.3 Cellulase + > 300 119 Glutaraldehyde
  • protease solutions were prepared using commercial protease preparation supplied by Sigma Chemical Sig a-Aldrich Company Ltd., Fancy Road, Poole, Dorset, BH17 7NH: ficin (4 ⁇ l ml -1 solution in PBS buffer at pH 6.5); papain (5 ⁇ l ml "1 solution in PBS buffer at pH 6.5); Protease K (2.8 mg ml -1 solution in PBS buffer pH 8.0); ⁇ -chymotrypsin (1.0 mg ml "1 solution in PBS buffer at pH 8.0) .
  • Paper square ⁇ (1.5 x 1.5 cm) prepared from water-leaf paper pulp strengthened with glutaraldehyde cross-linked cellulase were taken and incubated with the following treatments outlined in Table 5.
  • Paper sheet ⁇ prepared either from water-leaf paper pulo (0.2 g) wet ⁇ trengthened with glutaraldehyde cro ⁇ s-linked cellulase or with pulp (-0.2 g) prepared without any wet strength agent were taken and subjected to a multitude ⁇ of treatments.
  • the squares were then removed and dipped into phosphate buffer (pH 8.0) and placed in a universal bottle containing 20 ml fresh phosphate buffer (pH 8.0) .
  • the sample was then vortex mixed to ascerate the paper.
  • a water-leaf paper sheet (0.2 g) made from pulp prepared with PBS without any wet strength agent was placed in a universal bottle with 14 ml 1/3 strength PBS. The sample was vortex mixed to macerated the paper and the pulp was made into a fresh piece of paper.
  • a glutaraldehyde cross-linked cellulase strengthened paper sheet (0.2g) was cut into 1 cm 2 pieces and mascerated in a blender in 30 ml of 1/3 strength PBS. 20 mg T. reesei cellula ⁇ e (10 mg ml "1 ) and 0.5 ml glutaraldehyde solution (25% vv -1 ) were added. The sample was incubated on an orbital shaker for 60 min at room temperature, The pulp was u ⁇ ed to prepare a new ⁇ heet of paper.
  • the ⁇ e re ⁇ ult ⁇ indicate that GCC - containing pulp, when made into a new paper sheet, retains some wet tensile strength properties; that pulp produced by protease treatment, as opposed to physical disruption, generates stronger paper when recycled and that the further addition of GCC imparts the best wet tensile strength properties to the recycled sheets.
  • the glutaraldehyde used in the following examples was a 25% aqueous solution commercially available from Merck Ltd. (Poole, Dorset, U.K.)
  • the furnish used was a blend of ECF bleached hardwood and softwood pulps (ratio of 70:30 HW/SW) .
  • the stock wa ⁇ prepared with 1 / 3 PBS and no filler ⁇ were added.
  • Both the cellulase solution and glutaraldehyde solution were added to the thick (2% consistency) stock.
  • the sto ' ck was at ambient temperatures (20-25'C).
  • the cellulase solution was added first to the stock (avoiding any splashing or splattering of the solution) . When one minute had elapsed from the addition of the enzyme, the aqueous glutaraldehyde was added.
  • the incubation time of the additives was fifteen minutes, starting from the end of enzyme addition. During this incubation period the movement of the stock may appear to become easier/fa ⁇ ter. If this is apparent then reduce the stirrer speed as much as pos ⁇ ible.
  • the thick stock in the proportioner was then diluted to a consi ⁇ tency of 0.25% u ⁇ ing DEMI water only. Normal agitation speeds in the proportioner were employed to mix the stock.
  • the white water box was filled with DEMI water for handsheet formation.
  • the handsheet forming wire in place in the mould as ⁇ embly, one litre of stock from the proportioner was added to the Deckle Box, together with water from the white water box.
  • the contents of the Deckle Box were agitated with the perforated agitator (moved up and down five time ⁇ ) .
  • the agitator was re ⁇ ted on the surface of the water to help dampen the motion of the water in the Deckle Box.
  • the water was then pumped back to the white water box and the initial wet mat was formed.
  • foaming may occur in the Deckle Box. This foam may still persi ⁇ t after the initial wet mat i ⁇ formed and can be quite substantial. Some of this foam can be dispersed if the pump is kept on for a few seconds after the water has been removed so that air can be drawn through the mat.
  • the wet mat and handsheet wire were removed from the mould to the pres ⁇ .
  • the moisture content of the pressed sheet should be 70%.
  • the pressed sheet was then dried on an electrically heated drum dryer.
  • the surface temperature of the dryer was between 60'C and 105'C and the speed of the dryer was such that the pressed sheet was in contact with the hot surface for 35 to 180 seconds.
  • the final moisture content of the sheet should be between 4 and 7% (typically 5%) .
  • the sheet may stick to the surface of the drum dryer when the above conditions are employed. This may occur because of nonuniform pres ⁇ pressures being applied across the width of the sheet. Steps should be taken to avoid this.
  • the surface temperature of the drum dryer is below 70 * C, it is necessary to extend the contact time further or increase the initial pressing on the wet mat to remove more water or to do both. It is possible to reduce the moisture content of the pres ⁇ ed sheet to less than 60%.
  • the wet tensile breaking strength of paper and paper board is defined by method T 456 om - 87; the tensile breaking properties of paper and paper board is T494 om - 81; the HST (Hercules Sizing Test) i ⁇ defined as size test for paper by ink resi ⁇ tance T 530 pm - 83; and the Cobb test is defined by T 441 om - 90.
  • Standard drying conditions refers to drying at 105°C for 35 seconds
  • the wet and dry tensile strengths were determined by methods T456om-87 and T494om-81, respectively, and the ratio of wet to dry tensile strength expressed as a percentage. These are the data presented in the tables where the higher the value, the better the wet strength.
  • the sizing effect was measured by the HST (Hercules size test) (TAPPI method T530pm-83) and the data recorded in seconds. The higher the value, the better the sizing.
  • HST value is greater than 20g, more preferably greater than 12Og, more preferably greater than 200g. Size effect was also measured by the Cobb test (TAPPI method T441om-90) and the data recorded in grams/m 2 .
  • “Fully saturated” means that the paper showed no sizing at all.
  • the Cobb value is les ⁇ than 30g/m 2 , more preferably le ⁇ s than 2lg/m' !
  • bio-metalization of water-leaf paper was demonstrated.
  • the technique was based on the affinity of streptavidin for biotin.
  • the biotin label was linked to the cellulase which in turn was linked to streptavidin labelled with gold particles.
  • Biotinylated cellulase was incubated with the paper pulp in 1/3 PBS buffer (pH 7.4), containing Tween 20 (0.1% vv "1 ) for 45 min at room temperature with shaking. A paper square (6 cm 2 ) was formed, rolled and allowed to dry overnight at ambient temperature.
  • the Auroprobe BLplus labelled streptavidin conjugate and enhancer was used according to the manufacturer's recommendation to attach and visualize the gold particle ⁇ (Fostel et al . , Chromosoma, £0, 254, (1984); Hutchinson et al . , J. Cell Biol., 95, 609, (1982)).
  • the enhancer solution coated the gold particles with silver to create an orange/brown colour which was indicative of the presence of the metal ⁇ . Control ⁇ heets which did not contain the biotinylated cellulase did not develop the orange/brown colouration and hence were not coated with the metal.
  • the capacitance of bio etalized paper sheets was compared to control sheets to determine if the presence of the gold- labelled cellulase altered the capacitance characteristics of paper.
  • Paper sheets were produced from W-LP containing either cellulase, gold labelled cellulase, enhanced gold labelled cellulase and cellulase-free control ⁇ .
  • the sheet ⁇ were each held between two metal plates connected to a capacitance meter.
  • the metal plates were held in position in a jig which ensured that a constant and reproducible distance was maintained between the plates.
  • the capacitance (C) was calculated using the following equation
  • Two amylase enzymes were characterized using HPLC: an ⁇ -amylase (Type X-A crude preparation) from Aspergillus oryzae and amyloglucosida ⁇ e from A . niger (available from Sigma Aldrich Co. Ltd., Poole, Dor ⁇ et, United Kingdom).
  • the main catalytic peak ⁇ of each preparation were determined using a starch glucose-relea ⁇ e assay.
  • the binding efficiencies of each protein were determined against a range of starches with BSA controls included in the assessment.
  • the following qualitative a ⁇ say was used to detect glucose and cellobiose in test samples.
  • the assay was carried out in a micro titre dish at room temperature.
  • the same method ⁇ were al ⁇ o u ⁇ ed to produce an HPLC profile for the amyloglucosidase.
  • 100 ⁇ l of a 0.007 dilution in 0.1 M PBS (pH 7.0) was loaded onto the HPLC and monitored at 230 nm 0.1 AUS. 1 ml fractions were collected and tested for reducing sugars released from starch suspensions as above.
  • the sample was centrifuged at 13,000 rpm for 5 min and 100 ⁇ l samples loaded onto the HPLC column.
  • the binding of amyloglucosidase was also tested against cationic starch.
  • BSA was also used in the same way as a control. The final concentration of the BSA used was 0.2% (wv -1 ) in 0.1 M PBS.

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  • Paper (AREA)
  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

Ces procédés et compositions permettent d'améliorer les propriétés fluides, électriques ou de résistance d'un polymère par liaison à celui-ci d'une fraction effectrice par l'intermédiaire d'une protéine. On améliore ainsi en particulier les propriétés du papier en y liant une fraction pouvant lui conférer une propriété telle qu'une résistance accrue à l'état humide ou sec ou un encollage amélioré, grâce à une protéine telle qu'une cellulase pouvant se lier à la cellulose de ce papier.
EP96927804A 1995-08-16 1996-08-16 Procedes et composes chimiques permettant de modifier des polymeres Withdrawn EP0845031A1 (fr)

Applications Claiming Priority (3)

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GBGB9516766.4A GB9516766D0 (en) 1995-08-16 1995-08-16 Method and chemical compounds for modifying polymers
GB9516766 1995-08-16
PCT/GB1996/002009 WO1997007203A1 (fr) 1995-08-16 1996-08-16 Procedes et composes chimiques permettant de modifier des polymeres

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CA (2) CA2229358A1 (fr)
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GB9711984D0 (en) * 1997-06-11 1997-08-06 Vincent Julian F V Biodegradable waterproofing of paper & paper products
US6146497A (en) * 1998-01-16 2000-11-14 Hercules Incorporated Adhesives and resins, and processes for their production
US6468955B1 (en) 1998-05-01 2002-10-22 The Proctor & Gamble Company Laundry detergent and/or fabric care compositions comprising a modified enzyme
AU7275498A (en) * 1998-05-01 1999-11-23 Procter & Gamble Company, The Laundry detergent and/or fabric care compositions comprising a modified enzyme
WO1999064678A1 (fr) * 1998-06-08 1999-12-16 ALBUPRO Ltd Matiere fibreuse impermeable a l'eau
IL133134A0 (en) * 1999-11-25 2001-03-19 American Israeli Paper Mills Improved paper products
US7364890B2 (en) 2001-07-28 2008-04-29 Midwest Research Institute Thermal tolerant avicelase from Acidothermus cellulolyticus
EP1860121A3 (fr) * 2001-10-16 2008-12-03 Swetree Technologies Ab Procédé de modification de matériaux glucidiques polymères
AT412733B (de) * 2003-09-04 2005-06-27 Fine Foods Handels Und Beteili Verfahren zur beschichtung von papier, karton oder ähnlichen materialien
US20070131368A1 (en) * 2005-12-14 2007-06-14 Sonoco Development, Inc. Paperboard with discrete densified regions, process for making same, and laminate incorporating same
US7842362B2 (en) 2006-02-17 2010-11-30 Sonoco Development, Inc. Water-resistant wound paperboard tube
GB0609477D0 (en) * 2006-05-12 2006-06-21 Ciba Sc Holding Ag Process for making paper and paperboard
US8871922B2 (en) 2009-03-20 2014-10-28 Fpinnovations Cellulose materials with novel properties
CN102086611B (zh) * 2010-11-30 2012-11-14 王祥槐 一种用于改变和改善纤维表面性质的组合物和造纸方法
BR112014005290B1 (pt) * 2011-09-09 2021-11-09 Novozymes A/S Método para melhoramento da resistência do papel
US20140116635A1 (en) * 2012-10-10 2014-05-01 Buckman Laboratories International, Inc. Methods For Enhancing Paper Strength
CN108755216B (zh) * 2018-05-07 2021-04-13 希杰尤特尔(山东)生物科技有限公司 利用复合酶提升阔叶浆纤维强度的方法
CN109082936B (zh) * 2018-08-16 2020-11-24 内江师范学院 一种纸张表面施胶剂及其制备方法

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US3809605A (en) * 1972-10-30 1974-05-07 American Cyanamid Co Fibrous mats and sheets containing immobilized enzymes entrapped in their interstices
FI82734C (fi) * 1987-12-07 1991-04-10 Enso Gutzeit Oy Foerfarande foer framstaellning av en pappers- eller kartongprodukt och en genom foerfarandet framstaelld produkt.
US5340731A (en) * 1988-07-08 1994-08-23 University Of British Columbia Method of preparing a B-1,4 glycan matrix containing a bound fusion protein
WO1993005226A1 (fr) * 1991-08-29 1993-03-18 University Of British Columbia Procede de modification de fibres de polysaccharides

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CA2229588A1 (fr) 1997-02-27
WO1997007203A1 (fr) 1997-02-27
JPH11510701A (ja) 1999-09-21
DE69610841T2 (de) 2001-03-01
EP0845060B1 (fr) 2000-11-02
CN1199421A (zh) 1998-11-18
AU6824896A (en) 1997-03-12
BR9610219A (pt) 1999-06-15
JPH11510861A (ja) 1999-09-21
EP0845060A1 (fr) 1998-06-03
GB9516766D0 (en) 1995-10-18
TW353092B (en) 1999-02-21
CA2229358A1 (fr) 1997-02-27
CN1199439A (zh) 1998-11-18
WO1997007282A1 (fr) 1997-02-27
BR9610327A (pt) 2005-09-06
PT845060E (pt) 2001-03-30
AU6750296A (en) 1997-03-12
DE69610841D1 (de) 2000-12-07

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