JP2023532160A - Method for Enzymatic Treatment of Plant Biomass to Produce Textile Grade Fibers - Google Patents

Abstract

The present invention discloses an enzyme-based method for producing high quality textiles from plant-derived biomass. The present invention discloses a method for producing high quality textile grade fibers with no loss of quality parameters compared to textile grade fibers produced from cellulosic biomass by conventional methods using harsh chemical treatments. ing. The fibers produced from raw natural fibers in this way can be spun into yarns in an automated procedure and the yarns can be woven into high quality fabrics on power looms as well as hand looms.

Description

The present invention relates to the field of obtaining textile grade fibers from plant-derived biomass using enzymatic methods, and in particular to methods of treating various types of raw natural fibers by enzymatic means to obtain textile grade fibers. More particularly, the present invention relates to treating cellulosic biomass with enzymatically active methods to produce high quality textile grade fibers without the use of harsh chemicals or treatments.

As the world's population grows, the demand for textile materials continues to increase, and has nearly doubled over the past 16 years. At the same time as providing food and clothing for the world's growing population, there is also a growing need to conserve land and resources. Therefore, efforts are being made to obtain fiber and food from the same crop land resource. In addition, petroleum-based synthetic fibers are not biodegradable, which poses another challenge to the ecosystem. These challenges can be overcome if we can produce high-quality textile-grade fibers from various types of plant-based biomass, many of which are also agricultural by-products. Cellulose is the most abundant organic matter on earth and, in its natural and regenerated forms, is a major source of fiber for the textile industry. Plants are a major source of natural cellulosic fibers, and these cellulosic fibers can be used to produce a variety of different types of fibers for various industrial applications. These cellulosic fibers are obtained from plants grown primarily for fiber or from plants where fiber is primarily considered a by-product, such as coconuts, sugar cane, bananas, pineapples. Globally, agriculture produces millions of tons of agricultural by-products each year. Some by-products are used in animal feed and small-scale applications. Many agricultural by-products contain significant amounts of cellulose, especially fibrous. By-product fibers have not been widely used due to their limited availability, difficult extraction, poor spinnability, low-quality fibers that cannot be used to produce high-end products, and limited growing areas. Downstream utilization of agricultural by-products brings economic benefits to producers, as well as environmental benefits by reducing the amount of by-products discarded. In addition, products using these agricultural by-products are 100% biodegradable with added qualities such as breathability, hypoallergenicity, and high hygroscopicity.

Many agricultural by-products are particularly fibrous and contain significant amounts of cellulose, which can be used to produce fibers that can be used in a variety of industries. However, natural fibers extracted from plant biomass are generally coarse and rich in lignin and hemicellulose. Because of this, these fibers are very hard and thick, and their use is limited to a few areas such as handicrafts, handlooms, and upholstery. The process of converting such thick, stiff fibers into softer fibers involves chemical treatments that are very harsh and cause environmental problems. Also, the fiber quality achieved so far by conventional enzymatic methods is not sufficient for textile applications because it is difficult to spin into yarn, and spinnable grades require more harsh chemical processes, with drawbacks such as fiber brittleness and loss of luster.

Enzymes are known to have several advantages over chemical or mechanical processes for textile fiber production, but attempts to make textile-grade fibers from raw natural fibers using entirely enzymatic processes have so far been unsuccessful. Most of the processes that use enzymes use harsh chemical treatments during the process or use large amounts of enzymes for long periods of time. Furthermore, these processes do not produce high quality fibers from raw fibers, nor have they been shown to be spun into yarn in an automated manner and the resulting yarn can be woven using a power loom. The materials made by these processes are rough-made and hand-woven many times. Documents such as CN107385523A (7) and CN108977895A (8) describe the use of enzymes to produce fibers from hemp and corn, but these processes involve pretreatment with acids and alkalis and are treated with high concentrations of enzymes for long periods of time, resulting in fibers that are not as fine as the fibers obtained by the method of the present invention and that can be spun into yarn on a power loom.

The present invention presents an environmentally friendly method of enzymatically converting plant-derived biomass into high quality textile grade fibers without the use of harsh chemical or mechanical treatments. The methods disclosed herein use primarily enzymes to produce high quality textile fibers that are typically obtained by conventional methods through harsh chemical and/or mechanical treatments.

The present invention encompasses a method of converting raw natural fibers into textile grade fibers, the method comprising enzymatically converting raw natural fibers obtained from plant-derived biomass into textile grade fibers, wherein the textile grade fibers have a fiber denier of 75 dpf (denier per fiber) or less and a breaking strength of at least 50 g. In one embodiment, the fiber has a breaking strength of 175g.
In one embodiment, the plant-derived biomass is composed of plants selected from the group consisting of banana, pineapple, cannabis, nettle, flax, jute, sisal, and ramie.
In one embodiment, the total enzyme concentration in the fiber treatment vessel is 0.5-1%.
In one embodiment, the enzymatic treatment for converting raw natural fibers into textile grade fibers is carried out for 2-4 hours.
In one embodiment, the enzymes used in enzymatically treating the raw natural fibers are selected from the group consisting of cellulases, pectinases, hemicellulases, lignases, esterases, amylases, and peroxidases.
In one embodiment, the method further comprises alkaline protease treatment of the raw natural fiber prior to the enzymatic treatment step.
In one embodiment, the alkaline protease concentration present in the fiber treatment vessel is 0.1-0.3%.

In one embodiment, the method further comprises mechanically or manually opening the raw natural fibers prior to enzymatic treatment.
In one embodiment, the plant-derived biomass is not mechanically or manually treated to open the raw natural fibers prior to enzymatic treatment.
In one embodiment, the method does not include any chemical treatment steps.
In one embodiment, the method does not include any chemical pretreatment steps prior to the enzymatic step.
In one embodiment, the method further comprises performing a mild chemical treatment after the enzymatic treatment.
In one embodiment, the textile grade fibers produced from the methods disclosed herein can be spun into yarn by automated methods. In one embodiment, the produced yarn is woven or knitted into a fabric. In one embodiment, the yarn is woven into the fabric using a power loom or hand loom.
In one embodiment, yarns made from textile grade fibers produced from the methods disclosed herein are woven or knitted.
In one embodiment, the fibers are made into fabrics without being mixed with other types of fibers.
In one embodiment, the textile grade fibers produced by the methods disclosed herein are blended with other man-made or natural fibers to create at least a 20 count yarn.
In one embodiment, the present invention encompasses textile grade fibers made from the methods disclosed herein, which have high tensile strength, good stretchability, high tenacity, and finer diameter.

FIG. 1 is a flow chart showing the steps in the method for producing textile grade fibers from plant-derived biomass disclosed in the present invention.

DETAILED DESCRIPTION The present invention discloses a method for the enzymatic production of textile grade fibers from plant-derived biomass. More particularly, the present invention relates to producing high quality textile grade fibers by treating cellulosic fibers by enzymatic methods without the use of harsh chemical treatments. This method is environmentally friendly and the fibers produced are of the same high quality as conventionally produced from cotton.
Cellulose is the most abundant organic matter on earth and its natural and regenerated forms are the primary fiber source for textiles. Plants are the main source of natural cellulosic fibers. These cellulosic fibers can be used to produce different types of fibers for various industrial applications. Globally, agriculture produces millions of tons of agricultural by-products each year. Many agricultural by-products, especially fibrous, contain significant amounts of cellulose. Using more agricultural by-products brings economic benefits to producers, as well as environmental benefits by reducing the amount of by-product waste. In addition, this agricultural byproduct product is 100% biodegradable. By-product fibers have not been used extensively because of their limited availability, difficulty in extraction, poor end-product quality limiting their use in high-end products, and performance problems such as poor spinnability, rough texture, and stiff hand.

Conventionally, there is a process called "immersion" as a method of extracting fibers from plant stems, trunks and leaves. The traditional dipping process is Dew-Retting, which utilizes bacteria and fungi from the environment to delignify the fibers and transform them into a state suitable for use in conventional textile machinery. Field dipping has inconsistent results, poor fiber quality, is usually limited to limited areas, and occupies agricultural land during the dipping process. Chemical methods of dipping are used and these typically produce fibers with more consistent and improved physical properties, but such chemical methods pose many environmental problems, including waste disposal problems. Apart from that, the finished textile products are of poor quality in terms of brightness index and low tensile strength.
The present invention provides an enzymatic method for converting plant-based or plant-derived biomass into high-grade textile fibers. The methods disclosed herein use small amounts of enzymes and do not involve alkaline or acid pretreatment of the raw natural fibers. This method allows short enzymatic treatment times and yields spinnable fibers with very high quality indicators. This fiber can be spun into yarn in an automated way and the resulting yarn can also be woven into cloth on a power loom, so it can be used to make fabrics/textiles on an industrial scale.

Definitions As used herein, the term "plant-derived biomass" is defined as biomass derived from plants. It may be from plants specifically grown for its biomass, or it may be a by-product of the main crop. Plant-derived biomass can be from any plant, including naturally-growing plants or agricultural crops.
As used herein, the term "raw (raw) natural fibers" is defined as fibers that have been mechanically removed from plant biomass using manual processes or mechanical extractors. Examples of raw natural fibers include, but are not limited to, fibers obtained from banana, hemp, bamboo, nettle, flax, pineapple, ramie, jute, kenaf, cesar, abaca, coconut.

Raw fibers (raw fibers) are extracted from plant biomass by mechanical extractors. The machine peels off the biomass and extracts the bast fibers.

As used herein, the term "degumming" is defined as the process of separating fibers by removing biomolecules such as pectin, starch, hemicellulose, gums, and other biomolecules that bind the fibers together.

The terms "fiber treatment vessel" and "treatment bath" and "bath" are used interchangeably herein to refer to a vessel or bath in which enzymatic treatment of green fibers takes place. The proportion of enzyme used and the amount of raw fiber added to the bath will depend on the volume of the bath. A liquid in a container is also referred to herein as a "solution" or "liquid." It may be water or any other aqueous solvent with additives for optimal action of the enzyme.
The main component of plant cell walls is lignocellulose, which consists of lignin (15-20%), hemicellulose (25-30%), and cellulose (40-50%). These components form a complex three-dimensional network bound by covalent and non-covalent interactions.
Lignocellulose is commonly found, for example, in plant fibers, pulp, stems, leaves, husks, knotty stems, shells, and/or cobs, or wood and/or shrub fibers, leaves, branches, bark, and/or wood. Examples of lignocellulosic materials include agricultural biomass, e.g. agricultural and/or forestry materials and/or residues, branches, bushes, knotty stems, forests, cereals, grasses, short turnwood crops, herbaceous crops and/or leaves, crop residues such as corn, millet and/or soybeans, herbaceous materials and/or crops, forests, fruits, flowers, needles, logs, roots, saplings, shrubs, switch grasses, vegetables, fruit skins, vines, wheat grains, husks, hard and Softwoods, or any combination thereof, include, but are not limited to.

Hemicellulose is composed of monosaccharides such as L-arabinose, D-galactose, and D-mannose and xylan, a heteropolysaccharide substituted with organic acids such as acetic acid, ferulic acid, and glucuronic acid, interwoven with glycosidic and ester bonds. Depolymerization of this complex polymer is necessary for its efficient utilization in different industrial applications.

As used herein, the term "raw (raw) natural fibers" is defined as fibers that have been mechanically removed from plant biomass using manual processes or mechanical extractors. Examples of raw natural fibers include, but are not limited to, fibers obtained from banana, hemp, bamboo, nettle, flax, ramie, jute, kenaf, cesar, abaca, coconut.

Raw fibers (raw fibers) are extracted from plant biomass by a mechanical extractor, which delaminates the biomass and extracts bast fibers.

The terms "enzyme preparation", "enzyme cocktail" and "enzyme composition" are used interchangeably herein and refer to a preparation comprising at least one enzyme, which does not contain any chemicals.
As used herein, "Cellulase" or "cellulases" means an enzyme capable of hydrolyzing cellulose to glucose. Non-limiting examples of cellulases include mannan endo-1,4-β-mannosidase, 1,3-β-D-glucan glucanohydrolase, 1,3-β-glucan glucanohydrolase, 1,3-1,4-β-D-glucan glucanohydrolase and 1,6-β-D-glucan glucanohydrolase.

As used herein, "Xylanase" or "xylanases" refers to an enzyme that can hydrolyze xylan to xylobiose and xylotriose.
Xylanases are involved in the depolymerization of xylan into monosaccharides and xylooligosaccharides, endo-1,4-β-d-xylanase (EC 3.2.1.8), β-d-xylosidase (EC 3.2.1.37), α-glucuronidase (EC 3.2.1.139), acetylxylan esterase (EC 3.1.1.72), α-l-arabinofuranosidase (EC 3.2.1.55), p-coumarate esterase (3.1.1.B10) and ferulic acid esterase (EC 3.1.1.73).

The term "pectinase" includes any acid pectinase enzyme. Pectinases are a group of enzymes that hydrolyze the glycosidic bonds of pectic substances, mainly poly-L,4-α-D-galacturonide and its derivatives, and are understood to include the mature protein or its precursor forms, or functional fragments thereof that have essentially the activity of the full-length enzyme. Furthermore, the term pectinase enzyme is intended to include homologs or analogues of such enzymes. Pectinases can be classified according to their preferential substrates, highly or poorly methyl-esterified pectin and polygalacturonic acid (pectic acid), and their reaction mechanism, β-elimination or hydrolysis. There are two types of pectinase: the endo-type, which mainly cleaves polymers at random sites within the chain to give a mixture of oligomers, and the exo-type, which attacks from one end of the polymer and produces monomers and dimers. According to Enzyme Nomenclature (1992), several pectinase activities acting on the smooth part of pectin are pectate lyase (EC 4.2.2.2.2), pectin lyase (EC 4.2.2.10), polygalacturonase (EC 3.2.1.15), exopolygalacturonase (EC 3.2.1.67), exopolygalacturonase are included in the class of enzymes such as Nases (EC 4.2.2.9) and exopolyα-galacturonidases (EC 3.2.1.82).

Laccase belongs to the multicopper oxidase (MCO) enzyme family and is classified as benzenediol oxygen reductase (EC 1.10.3.2), also called urushiol oxidase, p-diphenol oxidase. Because it has low substrate specificity, uses oxygen as an electron acceptor, and produces water as a by-product, it is considered a versatile enzyme that can oxidize many phenolic and non-phenolic molecules.

Endo-1,4-β-d-mannanase (EC 3.2.1.78) is a catalyst that randomly cleaves β-d-1,4-mannopyranosyl bonds within the backbone of galactomannans, glucomannans, galactoglucomannans, and mannans. They release short-chain β-1,4-mannooligomers and can be further hydrolyzed to mannose by β-mannosidase (EC 3.2.1.25).

Alpha-amylase is a starch hydrolase. Amylase is responsible for hydrolyzing starch into oligosaccharides. α-Amylase hydrolyzes 1,4-α-glucosidic bonds in compounds containing 3 or more glucose molecules. β-amylase liberates (mainly) β-maltose from starch and other compounds.

In one embodiment, the amylase used in the present invention is α-amylase.

As used herein, enzymatic activity is defined in units. One unit of enzyme (U) is the amount of enzyme that catalyzes the reaction of 1 μmol of substrate per minute.
The activity definitions of the enzymes used in the present invention are shown below. Substrates used for activity measurement may be known substrates for a given enzyme. Furthermore, the enzymes used can be any known ones.

Cellulase:
One unit of activity corresponded to the amount of enzyme that released 1 μmol of D-form glucose [glucose] reducing sugar (as glucose) per ml per minute under assay conditions. Any suitable substrate can be used to assess activity. The substrate used herein is carboxymethylcellulose sodium salt-low viscosity (SIGMA-ALDRICH).

Xylanase:
One unit of activity corresponds to the amount of enzyme that releases 1 μmol of xylose reducing sugar (glucose equivalent) per ml per minute under assay conditions. The substrate used herein for the evaluation of xylanase activity is xylan (SRL) from beech wood.

Pectinase:
One unit of activity corresponds to the amount of enzyme that releases 1 μmol of D-galacturonic acid reducing sugar (glucose equivalent) per 1 ml per minute under assay conditions. The substrate used herein is apple-derived pectin (SIGMA).

Polygalacturonase:
One unit of activity corresponds to the amount of enzyme that releases 1 μmol of D-galacturonic acid reducing sugar (glucose equivalent) per ml per minute under assay conditions. The substrate used for activity evaluation in the present invention is polygalacturonic acid sodium salt (SIGMA).

amylase:
One unit of activity corresponds to the amount of enzyme that releases 1 μmol of maltose reducing sugar (glucose equivalent) per ml per minute under assay conditions. The substrate used for activity evaluation in the present invention is potato starch soluble (HIMEDIA).

Mannanase:
One unit of activity corresponds to the amount of enzyme that releases 1 μmol of mannose reducing sugar (as glucose) per ml per minute under assay conditions. The substrate used for activity evaluation in the present invention is carob seed-derived locust bean gum (SIGMA).

Laccase:
One IU is defined as the amount of enzyme required to oxidize 1 μmole of guaiacol per minute. The substrate used for evaluating the activity of the present invention is guaiacol (SIGMA-ALDRICH).

As used herein, the terms "textile grade fiber" and "textile fiber" are used interchangeably and refer to fibers that are soft and have properties suitable for making textiles.
Tensile strength and elongation at break are two of the most important mechanical properties for textile grade fibers. The tensile strength of fibers is often expressed in tenacity in units of force per denier or tex.

As used herein, the term "cellulosic fibers" is defined as fibers containing at least 20% cellulose and made of cellulose ethers or esters, which are of plant origin and can be obtained from plant bark, wood, leaves, or other plant parts. In addition to cellulose, fibers may contain pectin, hemicellulose, lignin as major constituents, apart from other minor constituents. The proportion of these components varies with the type of raw material and changes the mechanical properties of the fiber.

As used herein, the term "man-made fibers" is defined as fibers that do not occur in nature and are typically made from various chemicals or regenerated from plant fibers. Examples of man-made fibers include, but are not limited to, polyester; polyamide-(nylon); acrylic;

As used herein, the term "denier" is used to describe the fineness of a textile material quantified as the weight of the material in grams per 9,000 meters of that material.

Denier values given herein are denier values for each fiber or filament. Theoretically, denier can also be measured for yarns, but the denier values given herein refer to the denier value for each textile grade filament produced by the methods disclosed herein. 2 and single filament fibers. A general calculation method is as follows.
1 denier = 1g/9000m
= 0.11 mg/m

In practice, measuring 9000m is time consuming and impractical. Typically, a 900m sample is weighed and the result is multiplied by 10 to give the denier weight (9).

The term stretch is defined as a percentage of the starting length. Elastic stretchability is very important because non-elastic textile products are useless. They must be easy to deform and easy to recover. If the textile fiber is highly stretchable, it is easier to process and it is more comfortable to wear.

As used herein, the term "reflectance" of a fiber is defined as the percentage of light reflected by the material, or a measure of its reflection.
The term "breaking strength" of a fiber is defined herein as the maximum amount of tensile stress a material can withstand before breaking or deforming.
Tensile strength is a measure of the maximum force reached when breaking a fiber. Tenacity is a measure of the same force in relation to the linear density of the fiber or yarn. The ratio of the load required to break a sample to the linear density of that sample is called tenacity.

Breaking strength is the force applied to break the fiber relative to the cross-sectional area of the fiber, and is called breaking strength.

A loom is a device for weaving threads to obtain fabric. A loom creates fabric by interlacing threads that are aligned in the machine direction with threads that are aligned in the width direction.
hand loom. A handloom is a simple, human-powered machine used for weaving.
power loom. Power loom: A type of loom that uses mechanical force to weave patterns and threads into the fabric instead of human power.

Embodiments The present invention encompasses a method of converting raw natural fibers into textile grade fibers, the method comprising enzymatically converting raw natural fibers obtained from plant-derived biomass into textile grade fibers, wherein the textile grade fibers have a fiber denier of 75 dpf (denier per fiber) or less and a breaking strength of at least 50 g. In one embodiment, the fiber has a breaking strength of 175g.
In one embodiment, the plant-derived biomass consists of plants selected from the group consisting of banana, cannabis, sisal, pineapple, nettle, flax, jute, and ramie.
In one embodiment, the total enzyme concentration in the fiber treatment vessel is 0.5-1%.
In one embodiment, the enzymatic treatment for converting raw natural fibers into textile grade fibers is carried out for 2-4 hours.
In one embodiment, the enzyme used in enzymatically treating the raw natural fiber is selected from the group consisting of cellulase, pectinase, hemicellulase, lignase, esterase, amylase, or peroxidase.
In one embodiment, the method further comprises alkaline protease treatment of the raw natural fiber prior to the enzymatic treatment step.
In one embodiment, the alkaline protease is present in the fiber treatment vessel at a concentration of 0.1-0.3%.

In one embodiment, the method further comprises mechanically or manually opening the raw natural fibers prior to enzymatic treatment.
In one embodiment, the plant-derived biomass is not mechanically or manually treated to open the raw natural fibers prior to enzymatic treatment.
In one embodiment, the method does not include any chemical treatment steps.
In one embodiment, the method does not include any chemical pretreatment steps.
In one embodiment, the method further comprises performing a mild chemical treatment after the enzymatic treatment.
In one embodiment, the textile grade fibers produced from the methods disclosed herein can be spun into yarn by automated methods. In one embodiment, the yarn produced is woven or knitted into a fabric. In one embodiment, the yarn is woven into the fabric using a power loom or hand loom.
In one embodiment, yarns made from textile grade fibers produced from the methods disclosed herein are woven or knitted.
In one embodiment, the fibers are made into fabric without being mixed with other types of fibers.
In one embodiment, the textile grade fibers produced by the methods disclosed herein are blended with other fibers selected from cellulosic fibers, linen, cotton, tencel or higher to create at least a 20 count yarn.
In one embodiment, the invention encompasses textile grade fibers produced from the methods disclosed herein, which have higher tensile strength, better stretchability, higher tenacity, and smaller diameters than fibers produced by other conventional methods of processing raw natural fibers from agricultural waste.
In one embodiment, textile grade banana fiber is blended with other fibers in a 1:3 ratio.

In one embodiment, the method disclosed above further comprises mechanically treating the raw natural fiber prior to enzymatic treatment. In one embodiment, the method disclosed above further comprises mild chemical treatment of the raw natural fiber after enzymatic treatment. In one embodiment, mild chemical treatment is performed by bleaching followed by bleach neutralization.

In one embodiment, the chemical treatment is followed by removing excess water from the fiber or hydro-extracting. In one embodiment, the method further comprises preparing the fabric with a softening agent after hydro-extraction. In one embodiment, the softener is a silicone softener or an amphoteric softener (eg, Siligen, Sapamine, Zylon SFC). In one embodiment, the softeners used are amphoteric softeners.

One embodiment is a method of converting raw natural fibers into textile grade fibers, the method comprising the following steps. (a) opening fiber bundles from plant biomass into smaller fiber bundles by mechanical treatment, (b) subjecting the small fiber bundles to at least one enzymatic step, the enzyme being selected from the group consisting of pectinase, protease, cellulase, hemicellulase, amylase, and mannanase to produce textile grade fibers from the small raw fiber bundles, and (c) softening the fibers to a fiber diameter of 75 denier or less and a fiber breakage of 175 g. A process for producing textile grade fibers which is:

In one embodiment, the method includes enzymatic degumming of the fibers to remove biomolecules such as pectin, hemicellulose and lignin.

In one embodiment, examples of plant parts that can be used to extract plant-derived biomass include, but are not limited to, stems, leaves, and pseudostems.

In one embodiment, raw plant fibers are extracted using banana, ramie, and bamboo stalks as plant-derived biomass.
In one embodiment, the raw natural fibers are cellulose-based fibers and contain at least 20% cellulose. In one embodiment, the raw natural fiber also includes pectin, hemicellulose, lignin.

In one embodiment, the plant-derived biomass may be agricultural waste such as banana pseudostem, corn husk, corn stalk, rice straw, sorghum leaf, sorghum stalk, soybean straw, wheat straw, cotton stalk, and barley straw, and combinations thereof.

In one embodiment, the methods disclosed herein are used to convert banana, hemp or jute fibers into textile grade fibers.
In one embodiment, plant-derived biomass or raw fibers from plants can also be used directly for processing by the methods disclosed herein without mechanical extraction into smaller fiber bundles.

In one embodiment, the enzyme used in enzymatically treating the raw natural fiber is selected from the group consisting of cellulase, pectinase, hemicellulase.

In one embodiment, the enzymatic activities for converting raw natural fibers into textile grade fibers are pectinolysis, hydrolysis, and oxido-reductase activities according to the methods disclosed herein.

In one embodiment, the hydrolase activity removes non-cellulosic components from the plant biomass.
In one embodiment, the oxido-reductase activity enhances the brightness of the fiber.

In one embodiment, the methods disclosed herein further comprise enzymatic treatment followed by a mild chemical treatment to increase the whiteness index.

In one embodiment, the methods disclosed herein further comprise enzymatic treatment to increase the whiteness index followed by a mild chemical treatment, wherein the mild chemical treatment is performed with alkali and/or peroxide.

One embodiment of the present invention encompasses textile grade fibers produced by the methods provided herein.

In one embodiment, textile grade fibers produced by the methods disclosed herein have higher tensile strength, better stretchability, better spinnability, higher tenacity, lower resistance, smaller diameter, and higher brightness index compared to fibers obtained by chemical treatment of raw natural fibers.

In one embodiment, the textile grade fibers produced by the methods disclosed herein have a fiber diameter of 75 denier or less.
In one embodiment, the breaking strength of the textile grade fiber made from hemp is 50g or more.
In one embodiment, the textile grade fiber made from banana has a breaking strength of 175 g or more.

In one embodiment, the tenacity or strength of the fibers produced by the methods described herein is 2.5 grams/denier or greater.
In one embodiment, the stretchability of the fibers produced by the methods described herein is 5% or greater.
In one embodiment, the brightness (reflectance) is 65 or greater.
In one embodiment, the textile grade fibers produced by the methods disclosed herein are used in the production of any material including, but not limited to, apparel, suiting fabric-shirting, upholstery, handicrafts, doll hair, and footwear.
In one embodiment, the fibers produced by the methods disclosed herein are spun into yarn.

In one embodiment, a power loom is used to produce fabric from yarn spun from textile grade fibers produced by the methods disclosed herein.
In one embodiment, a handloom is used to produce fabric from yarns spun from textile grade fibers produced by the methods disclosed herein.
In one embodiment, yarns from textile grade fibers produced by the methods disclosed herein are further woven or knitted into fabrics.
In one embodiment, fibers made by the methods disclosed herein are used to make nonwoven products.

In one embodiment, the textile grade fibers produced by the methods disclosed herein are further blended with other natural or man-made fibers, including, but not limited to, regenerated cellulose fibers, linen, cotton, and man-made fibers.

In one embodiment, a method of producing textile grade fibers from plant-derived biomass comprises at least one step of enzymatic treatment.

In one embodiment, the methods disclosed herein are used to produce textile grade fibers from banana pseudostems. In one embodiment, a method of producing textile grade fiber from banana biomass comprises one step of enzymatically treating banana fiber produced by the methods disclosed herein. In one embodiment, this step comprises treatment with an enzyme selected from the group consisting of hemicellulase, pectinase, endocellulase, lignin oxidase and mannanase.

In one embodiment, the methods disclosed herein are used to produce textile grade fibers from cannabis biomass. In one embodiment, a method of producing textile grade fibers from cannabis biomass includes two steps of enzymatic treatment. Banana fiber produced by the methods disclosed herein. In one embodiment, the first step comprises treatment with a protease. In one embodiment, the second treatment is with an enzyme selected from the group consisting of hemicellulase, pectinase, endocellulase, lignin oxidase and mannanase.

In one embodiment, yarns from fibers produced from hemp by the methods disclosed herein are blended with other fibers in a 1:1 ratio to produce a fabric. In one embodiment, yarns from fibers produced from bananas by the methods disclosed herein are blended with other fibers in a 1:3 ratio to produce a fabric.
In one embodiment, the total time required for enzymatic treatment is 2-4 hours.

In one embodiment, no detergent is used to treat raw fibers for enzymatic processing into textile grade fibers.
In one embodiment, no chemical or water soaking step is performed in the enzymatic methods disclosed herein.
In one embodiment, no chelating agent is used in any of the processing steps in the enzymatic methods disclosed herein.
In one embodiment, no acid treatment step is performed in the enzymatic method disclosed herein for processing raw natural fibers into textile grade fibers.

In one embodiment, the enzymatic process disclosed herein does not involve an alkaline treatment step to process raw natural fibers into textile grade fibers.
In one embodiment, the enzymatic treatment is optionally followed by an alkaline treatment step to bleach the fibers produced by the enzymatic treatment and convert the raw natural fibers into textile grade fibers.

Table 1 highlights features of the methods disclosed herein.

Example Enzyme activity was assayed by the method described in the detailed description (references 1-6).
The enzyme sources used in this experiment were:
Cellulase/Xylanase: Trichoderma reesei
Pectinase, Polygalacturonase, Lipase: Aspergillus niger
Mannanase: Bacillus sp.
Laccase: of fungal origin, with a minimum activity of 25 U/ml.

Example 1
A) Banana fiber material: Banana fiber (100-120 denier in diameter), which is the raw material of banana pseudostem
Composition: Banana fiber consists of cellulose (40-45%), hemicellulose (12-15%), lignin (10-12%), pectin & wax (2-3%) and other substances (30-35%).

Process conditions:
The raw banana fibers obtained were cut into lengths of about 40 mm. The fibers were then loaded into stainless steel tubes of a launderometer (model number WFT8X500, JK & PC Texlab) with the process conditions and times described in Table 2 for stepwise processing as described in FIG.
First step, enzymes: The enzymes used in the enzymatic process were hemicellulase (500000 IU/Kg of fiber), pectinase (100000 IU/Kg of fiber), endocellulase (50000 IU/Kg of fiber), lignin oxidase (10000 IU/Kg of fiber) and mannanase (20000 IU/Kg of fiber). An enzyme composition containing these enzymes was added to the water-soaked fabric in an amount of 5 g per liter. This treatment was carried out at optimal conditions of 50° C. and pH 5 for 2 hours.
After treatment, the water was drained and refilled.
2nd step, bleaching: Bleaching was done with a _solution of 0.5% alkaline NaOH and _H2O2 at 100°C for 1 hour.
Third step, hot wash: After bleaching, the bath was drained and refilled and hot washed at a temperature of 85°C for 10 minutes. After treatment, the bath was drained.
The fourth step, neutralization, was performed with acetic acid at 50°C for 10 minutes. After this time, the water was drained.
In the fifth step, a softening treatment was performed at pH 5.0 and a temperature of 50° C. for 30 minutes using a softening agent. After treatment, the bath was drained.
After the process was finished, the fibers were squeezed and finally air-dried (reaching 8-10% moisture content).
Sixth step, after drying, the fibers were manually opened to separate the fibers that were stuck together.
Table 2: Process step conditions for banana fiber treatment

result banana fiber
* ASTM (American Society for Testing and Materials) is an international standardization body.
** Coefficient of Variation (CV) is the standard deviation (SD) expressed as a percentage of the mean (CV % = (SD/mean) x 100). It is the same as the stretch measurement of fibers.

Textile grade banana fiber produced by enzymatic method followed by bleaching showed excellent fiber properties in terms of fineness, softness and whiteness in visual evaluation, and excellent fineness and stretchability in test results without loss of fiber strength.

Example 2
Material: raw hemp thread (140-160 denier)
Cannabis raw fiber composition: cellulose (70-75%), hemicellulose (15-20%), lignin (3.5-5.7%), pectin (0.8%), water-soluble substances (1.6%) and other substances (oils, waxes, etc., 1.2-6.2%).
Process conditions:
Raw fibers obtained from cannabis plant stems were cut into 40 mm lengths. The fibers were then loaded into the stainless steel tubes of a launderometer at the process conditions and times described in Table 4 (150 ml of solution for 10 g of fiber) for the stepwise processing as described in FIG.

First step, enzymatic treatment 1: The first step of enzymatic treatment was alkaline protease (50000 U/Kg of fiber). The fibers were soaked in water and the dose of enzyme given was 2 gpl. Treatment was carried out at 60° C. and pH 10 for 1 hour. After treatment, the fibers were neutralized with acetic acid at 50°C for 10 minutes.

Second step, enzyme treatment 2: The enzymes used in enzyme treatment step 2 are a cocktail of hemicellulase (500000 IU/kg fiber), pectinase (75000 IU/kg fiber), endocellulase (20000 IU/kg fiber), lignin oxidase (2000 IU/kg fiber) and lipase (5000 IU/kg fiber).
The enzyme cocktail was added to the water-soaked fibers at a dose of 5 gpl. The optimum conditions for the enzyme cocktail process step are 50 ^° C. and pH 5-6. Treatment was carried out for 2 hours. Drained the water and refilled.

3rd step, bleaching: Bleaching with 0.5% alkaline NaOH and _H2O2 solution, _the process is done in the same chamber for 1 hour.
After treatment, the fabric is washed with water at 85 ^° C for 10 minutes. The bath was drained and refilled with water.
Fourth step, neutralization: In addition, the bath was neutralized with acetic acid at a temperature of 50 ^° C. for 10 minutes.
In the fifth step, a softening treatment was performed at pH 5.0 with a softening agent at a temperature of 50 ^° C. for 30 minutes. After treatment, the bath was drained.
After the process, the fibers were squeezed and finally air-dried (to 8-10% moisture).
Sixth step, after drying, the fibers are manually opened to separate the fibers that are attached to each other.
Table 4: Process step conditions for cannabis fiber treatment

result

Conclusion:
The cannabis fibers treated by the methods disclosed herein showed good results in terms of fineness, softness and fiber clarity by visual evaluation. The test results showed good fiber fineness and breaking strength. Also, the fiber length after treatment is not reduced.

References
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Claims (13)

1. A method of converting raw natural fibers into textile grade fibers, the method comprising the step of enzymatically treating raw natural fibers obtained from plant-derived biomass to convert them into textile grade fibers, wherein the textile grade fibers are no more than 75 denier per filament and have a breaking strength of at least 50 g. 2. The method of claim 1, wherein the plant-derived biomass comprises plants selected from the group consisting of banana, cannabis, nettle, flax, jute, and ramie. A method according to claim 1, wherein the total enzyme concentration in the fiber treatment vessel is 0.5-1%. The method according to claim 1, wherein the enzymatic treatment is performed for 2-4 hours. 2. The method according to claim 1, wherein the enzyme used in the enzymatic treatment of the raw material natural fiber is selected from the group consisting of cellulase, pectinase, hemicellulase, lignase, esterase, amylase, and peroxidase. 2. The method of claim 1, comprising treating the raw natural fiber with an alkaline protease prior to the enzymatic treatment step. 7. The method of claim 6, wherein the alkaline protease is present in the fiber treatment vessel at a concentration of 0.1-0.3%. 2. A method according to claim 1, characterized in that it does not comprise any chemical treatment steps. 2. The method of claim 1, further comprising bleaching after enzymatic treatment. A textile grade fiber produced from the method of claim 1, characterized in that the fiber can be spun into yarn by an automated process. 11. The textile grade fiber of claim 10, wherein the yarn made from said fiber is woven or knitted. 11. The textile grade fiber of claim 10, wherein said yarn is woven into fabric by a power loom or a hand loom. A textile grade fiber obtained from the process of claim 1, blended with other man-made or natural fibers and spun to make a yarn of at least 20 count.