摘要:
The present invention relates to a DNA sequence, which codes for endomannanase produced by fungi of the genus Trichoderma and transferred into a yeast or fungus strain induces that strain to produce endomannanase, as well as to a method for isolating genes coding for endomannanases. The invention also relates to vectors, yeast strains and fungal strains containing the DNA sequence. Furthermore, the invention provides an enzyme product containing at least one endomannanase, which contains at least one of the following endomannanases produced by fungi of the Trichoderma genus: an enzyme having mannanase activity and an isoelectric point (pI) of about 3.8, an enzyme having mannanase activity and a pI of about 4.1, an enzyme having mannanase activity and a pI of about 4.5, an enzyme having mannanase activity and a pI of about 5.4 and an enzyme having mannanase activity and a pI of about 6.5, the isoelectric points being determined by isoelectric focusing. The endomannanase enzyme and enzyme products according to the invention can be used for hydrolyzation of mannopolymers, in particular in connection with bleaching of lignocellulosic pulps.
摘要:
The present invention relates to a DNA sequence, which codes for endomannanase produced by fungi of the genus Trichoderma and transferred into a yeast or fungus strain induces that strain to produce endomannanase, as well as to a method for isolating genes coding for endomannanases. The invention also relates to vectors, yeast strains and fungal strains containing the DNA sequence. Furthermore, the invention provides an enzyme product containing at least one endomannanase, which contains at least one of the following endomannanases produced by fungi of the Trichoderma genus: an enzyme having mannanase activity and an isoelectric point (pI) of about 3.8, an enzyme having mannanase activity and a pI of about 4.1, an enzyme having mannanase activity and a pI of about 4.5, an enzyme having mannanase activity and a pI of about 5.4 and an enzyme having mannanase activity and a pI of about 6.5, the isoelectric points being determined by isoelectric focusing. The endomannanase enzyme and enzyme products according to the invention can be used for hydrolyzation of mannopolymers, in particular in connection with bleaching of lignocellulosic pulps.
摘要:
The present invention concerns a method for enzymatic treatment of lignocellulosic materials which contain xylan-polymers, such as cellulose kraft pulps. According to a method of the present kind, at least a part of the hexenuronic acid groups present in the material is selectively removed in order to remove metal ions from the pulp, to change the surface charge thereof, to improve the brightness stability of the pulp and to render the material more suitable for enzymatic treatment.
摘要:
The present invention concerns a process for reducing the susceptibility of lignocellulosic material to unwanted yellowing, particularly yellowing caused by light and heat. According to the invention, the fibres are activated enzymatically or chemically and then contacted with a modifying agent capable of bonding to the oxidized fibre material, rendering the lignocellulosic fibre material improved resistance to brightness reversion. By means of the invention, brightness reversion caused by light or heat or a combination thereof can be retarded and even stopped.
摘要:
The present invention concerns a process for producing fibre composites. In particular, the invention provides a novel way of producing biodegradable composites comprising a hydrophobic polymer material and a reinforcing component of fibres derived from plant materials. Composite material produced by means of the present invention has improved strength properties and enhanced adhesion between the bifunctional fibre and the natural or synthetic polymer.
摘要:
The present invention relates to fibre compositions. In particular, the present invention concerns a process for producing a fibre composition comprising a lignocellulosic fibre material and a synthetic, electrically conductive polymer formed by polymerized monomers. The invention provides for good adhesion between the fibre matrix and the polymer, because the monomer is polymerized directly on the fibre. The conductivity of the polymer is improved and the electrical properties and conductivity levels of the modified fibre can be adjusted by changing the amounts of the electrically conductive polymer.
摘要:
The present invention concerns a process for modifying a lignocellulosic fibre material. In particular, the present invention gives new properties to the fibrous matrix of the material. This is achieved by producing fibrous products with modified properties by activating the fibres of the matrix with an oxidizing agent and attaching compounds to the activated fibre in order to incorporate desired, pre-selected properties in to the fibre matrix. The invention makes possible to produce novel kinds of fibrous materials having practically a large variety of properties. Examples of such properties include hydrophobic hydrophilic character.
摘要:
The present invention relates to polyesterases having cutinase and/or suberinase activity obtainable from Coprinus and Trichoderma. The invention further relates to a method for producing the polyesterases, and to polynucleotides, vectors and host cells used therein. The enzymes are useful in hydrolysing cutin, suberin and other polyesters for example in treating agricultural or food raw materials, or wood raw materials, pulp and paper products and waste, and in modifying polyester fibers, or in laundry and dish applications.
摘要:
Extracellular tyrosinases obtainable from Trichoderma spp. and methods for producing them by recombinant technology. The enzymes are particularly useful in cross-linking food proteins.
摘要:
The present invention relates to a method for modifying polyamide. The method comprises that polyamide is contacted with an enzyme preparation comprising an effective amount of protease enzyme in aqueous environment under conditions suitable for the function of the enzyme. The enzyme is preferably selected from the group of aspartic proteases, cysteine proteases and metallo-proteases.