Application of Enzymes on Textile Proccesing

1. BAHIR DAR UNIVERSITY
ETHIOPIAN INSTITUTE OF TEXTILE AND
FASHION TECHNOLOGY (EiTex)
Advanced Coloration Technology(ACT)
Seminar on Enzymes in textile processing
Prepared By: Taame Berhanu (ID NO-R/TCH/07/08)
Submitted to: Dr. Kedar, & Mr. Murthy
Sub. Date – 14/02/2016

3. Outlines
 Introduction
 Bio- singeing
 Enzymatic Desizing
 Enzymatic scouring
 Enzymatic Bleachi ng
 Bio-finishing(bio polishing & bio washing)

4. Introduction
 Enzyme is a Greek word ‘Enzymos’ meaning ‘in the cell’ or
‘from the cell’.
 They are the protein substances made up of more than 250 amino
acids.
 Amylase, Protease, Cellulase, Catalase, Laccase, Pectinase etc. are
widely used in textiles.
 Enzyme is specialized high molecular weight protein produced
within an organism, which is capable of catalyzing specific chemical
reaction. They are also known as "Biocatalyst".

5. A small quantity of enzyme is able to decompose a large quantity of
substance it acts upon. Enzymes are usually named by the
substances degraded in the reaction it catalyzes.
The history of enzymes in textile:
Amylase : Cotton Desizing (1952)
Protease: Wool finishing, Degumming of silk ( 1984)
Cellulase: Wash down effect on indigo dyed denim (1987)
Catalase: Decomposition of residual H2O2 known as Catalase-Bleach clean up or
peroxide killer (1993)
Laccase: Indigo dyed Denim Bleaching (1996)
Peroxidase: cotton Bleaching (1999)
Pectate Lyase (Pectinase, Lipase): Bio-scouring (2003)

6. Source of enzyme:

7. Classification of enzymes :
•Oxido reductases – catalyze oxidation-reduction reactions involving transfer
of atom or electrons.
•Transferases – Transfer of functional groups.
•Hydrolases – catalyze cleavage reaction by hydrolysis.
•Lyases – Addition to double bond or its reverse
•Isomerases – catalyze intermolecular rearrangements to form an isomer.
(Isomer –Same molecular formation but different structural formula)
•Ligases – split C-C, C-O, C-N, C-S or C-halogen bonds without hydrolysis or
oxidation.
Hydrolases type of enzyme is mostly used in textiles.

8. Reasons @ which Enzymes are preferred in textiles:
Accelerate the rate of the reaction.
Specific in action.
Low temperature operation.
Safe and control is easy.
Replace harsh chemicals.
No pollution.
Biologically degradable.
present in very less amount in body and have specific life
span.
Low energy requirements, mild conditions of use, safe to
handle, non- corrosive in their applications

9. Factors which affects the Activity of enzymes :
Concentration of specific enzymes
Concentration of its substrate
pH of reaction (Each enzyme shows its highest activity
at a specific pH.)
Temperature of reaction (function in a particular
range of temperature )
Concentration of salts
Presence of activator or inhibitor
Time required to carry out the reaction

11. Model for Enzyme Action
•Each enzyme is specific and catalyzes only one reaction at a time
•Enzymes combine with their substrates to form temporary
enzyme-substrate complex.
•Enzymes can be used again and again.
•Enzyme catalyzed reactions are sensitive to temperature and pH.
•Enzyme catalyzed reactions can be slowed down or stopped by
inhibitors.
•Enzymes lower the activation energy of a reaction thus making
the reaction to occur very rapidly with large turnover numbers.

12. Role of Enzymes in Textile Processing

14. Lock and key model for enzyme
action

16. Application of Enzymes on Textile processin
 Fading
 Backstain Cleanup
 Biopolishing
 Biosoftening - wool
 Print washing
 Silk degumming
 Bio-scouring
 Bio-bleaching
 Washing off Reactives
 H2O2 removal
 Effluent colour removal
 Fiber retting and carbonizing
 Detergent
• Denim – fashion and colour.
• Special Proteases
• Cellulases increase depth.
• Colour yield & shrinkage.
• Brightens colour.
• Higher depth.
• Opens newer possibility.
• Denim – different effects.
• Reactive soaping.
• Aids level dyeing,
consistency.
• Environment friendly.
• Processing flax, ramie, wool
etc.
• Blend of amylase, protease,
lipase etc.

17. Enzymatic singeing
•Removal of protruding firbres from cotton by cellulase Enzymes
replacing convention singeing operation by burning protruding fibres. This
process is known as bio-singeing.
•Mostly Bio – singieng is used for lose fabrics (knitted fabrics)

18. Enzymatic Desizing
•Enzymatic desizing is degrading of starch size cotton fabrics using
enzymes.
•Amylase are the enzymes that hydrolyze & reduce the molecular
weight of amylose & amylopectin molecules in starch, rendering it
water soluble enough to be washed off the fabric.
•Enzymatic desizing is the most widely experienced method to desize
the starch.

19. Two types of amylase used for desizing of cotton fabric:
1. Alpha amylase
2. Beta amylase
•Alpha amylase attack the chain at random points. The
molecular weight of the starch is rapidly reduced facilitating
complete removal.
•Beta amylase, start at a chain end removing one maltose
unit at a time.
•The molecular weight is gradually reduced thereby taking a
longer time to complete breakdown.

20. Mechanism of starch breakdown with amylase

21. Advantages Enzymatic Desizing
Time required for the desizing process is less.
 It is continuous process, so greater production can be achieved.
 Closely constructed fabric can be easily desized, due to the effective enzyme action.
 There is no chance for the cellulose to get hydrolysed, as in acid desizing.
Disadvantages
Lower additional cleaning effect towards otherimpurities.
No effect on certain starches (e.g. tapioca starch)

22. Bio - scouring
Bioscouring is a process by which alkaline stable pectinase is used
to remove pectin and waxes selectively from the cotton fibre.
 Pectinase, as the name suggests, hydrolyses pectins present in
cotton as a non-cellulosic impurity.
This process is substrate-specific and does not alter the cellulose
component.
It takes place at lower temperatures and does not swell or remove
the seed coat fragments called motes, which can be beneficial when
scouring for the 'natural look'.

23. Types of enzymes that are used for bio-scouring process
Pectinase:-Pectinases are used for the removal pectic substances
from cotton.
Lipases:- They are used for the removal of natural fatty substances
from cotton
proteases:- proteases are enzymes that catalyse the hydrolysis of
proteins.

24. Mechanism of bio-scouring
Pectinase enzymes can be used. In general, it can be said that the
pectinases or pectinolytic enzymes catalyze the random hydrolysis 1, 4-
alpha-D-galactosiduronic linkages in pectin substance.
There are Four main types of enzymes are used to break down pectin
substances namely protopectinases, pectin esterases,
polygalacturonases and pectin lyases.
Protopectinases: These enzyme catalyze the solubilisation of
insoluble protopectin and give rise to highly polymerized soluble pectin.
Protopectin (Insoluble) + H2O Protopectinases Pectin ( Soluble)

25. Pectin Esterases: These liberate pectin and methanol by de-esterifying
the methyl ester linkages of pectin backbone.
They are active in the pH range of 4-8. Optimal
temperature range for maximum activity is 40- 50
degree C.

26. Pectin Lyases:Transeliminase or shortly lyase (depolymerase) catalyses
the cleavage of α (1 4) bonds in polygalacturonan chain without releasing
water and creating a double bond (producing an unsaturated product)
between the C4 and C5 atoms. Endo and exo enzymes work within or at the
end of the chain, respectively, similar to the polygalacturonases.

27. In a much simplified way, the action of the above mentioned Pectinase
enzymes can be summarized pictorially in the figure given below:

28. Comparison of Bio-Scouring and Alkali Scouring
Bio-scouring
 Blend of Enzymes-Pectinase +
Protease
 Removes Pectin, protein, Wax, Oil
etc
Alkaline-scouring
Sodium Hydroxide
Remove Pectin, Protein,
Wax, Oil, Cellulose

29. Results of Bio and Alkaline scouring
Bio-scouring
 Soft Handle
 cellulose with complete removal of
Impurities
 No core Alkali neutralization, thus
less washing cycle
Alkaline-scouring
 Harshness
 cellulose with complete
removal of Impurities and
partial Callulose
 Required core alkali
neutralization, thus more
washing cycle

30. Cost
Bio-scouring
 Direct cost is more
 but Overall cost is less (Grey to finished)
 Less chemical cost
 Energy saving
 Time saving
 Less water consumption
 Less weight loss of fabric
 Less dye loss
 Less effluent treatment
cost
 Less Effluent Cost:
Alkaline-scouring
Direct cost is less
but Overall cost is more
(Grey to finished)

31. Advantages of Bio-scouring
•Save energy
•Save cost
•Water saving
• Temperature saving
•Time saving
•Smoother surface profile(Fully retain cellulose structure)
•Lesser weight loss
•Lesser costs of auxiliaries
•Mild application condition
•Environmental benefits
•Reduces effluent treatment process/ ETP cost

32. Disadvantage of bio-scouring
Inability of removing of cotton fiber waxes.
Enzyme activity can, however, be reduced or even completely
destroyed (denatured) by high temperatures, extremes of pH and high
concentrations of electrolytes that destroy their three-dimensional
structures. Heavy metal ions and oxidizing and reducing agents also
deactivate the enzymes.
The degree of whiteness is often less and the process is not suitable
for removing seed-coat fragments and mote adequately.

33. Bleach Killing
In bleaching, especially with hydrogen peroxide, the reactive dyes are
very much sensitive to residual peroxide.
The residual peroxides are converted into water and Oxygen by using
the enzymes which shows better results than traditional method.
Reaction takes place at 30-400 C and pH 5.5-7.5 for 15 min
Enzymes like Peroxidases, Glucose oxidases, etc are used.

34. •Catalase is used for the removal of H2O2 after bleaching.
•One catalase molecule can convert 40 million molecules of
hydrogen peroxide to water and oxygen per second.
Efficiency of H2O2 removal

35. Cost saving

36. Bio - finishing
Bio-washingThis process is removal of surface dyes from fabrics.
• Neutral stable cellulase enzyme is used for bio-
washing.
•This enzymes replaces the pumice stones .
•It is produced from humicola isolans.
• It is leading to decolourisation without loss in
fabric strength.
•This enzyme acts at pH of 6

38. Bio-polishing
• Bio-polished cotton is a type of cotton that has been treated with
enzymes, mostly cellulases. Cellulases are enzymes that digest or
break down cellulose, the main fiber that is present in plants.
• It is a finishing process of cellulosic fabrics and garments.
•This process is improving surface of the material .
•This process is also called enzymatic singeing .
• Bio-polishing with acid cellulose effectively reduces fabric fuzz and
pilling on denim materials.
Disadvantage of BP
Loss in weight
 Loss in strength

40. Hairiness fluffs and pills are removed.
 Material sticking (the burr effect) is prevented.
 Improved handle
 Achievement of surface smoothness and a clear structural appearance.
 Improved luster.
 Material texture relaxation
 Increased flexibility and therefore a soft handle even with over end products
and mercerized fabric.
 Improved sew ability.
 Fast to washing, low pilling tendency, no napping in use, or during care
operation.
 Stone wash effect without pumice stone and dyestuff destroying chemicals.
 Poor quality, uneven, napped, knoppy material surface (i.e.) typical second
quality goods are converted into elegant, lustrous, soft, top quality with a fine, high
quality surface appearance.
Advantages of bio-polishing

41. PROTEASES
Proteolytic enzymes or proteases catalyse the hydrolysis of certain peptide
bonds in protein molecules. The general reaction can be illustrated by:

42. •The largest application of proteases is in laundry detergents, where
they help removing protein based stains from clothing (Blood stains)
•Proteases may also be used to remove the stiff and dull gum layer of
sericine from the raw silk fibre to achieve improved lustre and
softness. The process is known as degumming of silk
•Protease treatments can modify the surface of wool and silk fibres to
provide new and unique finishes.
•Research has been carried out on the application of proteases to
prevent wool felting.

43. Conclusion
Replacement of harsh and energy demanding chemical treatments by
Environment friendly routes to textile auxiliaries such as dyestuffs
Require less effluent treatments
Low cost and less energy consumption(active in mild conditions , low
temperature and moderate PH)
No damages to materials
superior quality of the product
Reduction in the consumption of chemicals
In feature , one can expect to see many more developments in textiles , based
on above technology's

44. Reference
Bio- Processing Of Textiles” by Abhishek Jadhav & Javed Sheikh.
“Chemistry & Technology of Fabric Preparation & Finishing” by Dr.
Charles Tomasino.
“Applying Enzyme Technology for Sustainable Growth” by Guifang Wu,
Han Kuilderd & Sonja Salmon (Novozymes).
“Bio Polishing of Knit Goods” by Prof. S.K. Laga, Prof. Dr. A.I. Wasif & Mr.
Karan Shah (Textile & Engineering Institute, Ichalkaranji).
“CIRCOT’s Eco-friendly Process for Scouring of Cotton Textile: Bio-
scouring” –Annual article of Central Institute for Research on Cotton
Technology, Mumbai.
“Bio-vision in Textile Wet Processing Industry- Technological
Challenges” by C. Vigneswaran, N. Anbumani and M.
Ananthasubramanian. Journal of Textile & Apperal, Technology &
Management; Volume 7, Issue 1, spring 2011.
“Effects of industrial enzyme wash on denim apparel characteristics”
by M. M. Rahman, Daffodil International University. www.ptj.com.pk ;
January 2011.