Study On The Biological Modification And Dyeing Of Textile Material With Lipase And Violacein

Textile biotechnology is one of future development trends of textile industry.Biotechnology has been widely applied in textile industry,including textile pretreatment,finishing,biological decolonization of textile and treatment of dyeing wastewater.The technology of amylase desizing,bio-polishing has been successfully applied in production practice.In recent years,biotechnology mainly applied in the pretreatment,finishing of natural fiber,including cotton,flax,silk and wool,but the study on the bio-modification,bio-dyeing of textile materials,especially synthetic fiber,is still in its infancy.On the one hand,study on the application of lipase in modification of polyester.First,the lipase purified by ammonium sulfate salting-out.The SDS-PAGE analysis and UV-spectrum of purified lipase were measured.Second,the effects of temperature,p H,metal ions and surfactant on the lipase activity were investigated through single factor experiments.The enzyme stability was also discussed.The interaction between lipase and lauryl sodium sulfate(SDS)were investigated by fluorescence spectroscopic analyses.The last,modified polyester by the mixture of lipase and JFC,the effects of enzyme dosage,temperature,p H,reaction time were investigated by test the concentration of terephthalic acid of working fluid.The properties of the fabric modified with lipase were measured,including the weight loss rate,moisture regain,antistatic property and surface morphology of polyester.On the other hand,study on the application of violacein(Vio)in biological dyeing.First,the effects of temperature,p H,metal ions,ultraviolet and organic solvent on the visible absorption spectra were investigated.Second,dyeing the silk and nylon 6 by violacein under the conditions of different temperature and different p H.And then,the colorfastness of dyed fabric tested,including color fastness to washing,rubbing,and light.The antibacterial property and UV-protection property of dyed fabric were also researched.The last,in order to improve the color fastness to light,ascorbic acid was used;the finishing effect was evaluated by test the color difference of the dyed fabric before and after light.1.The suitable dosage of ammonium sulfate is 60%,and the retention of lipase activity is about 95%.The purified lipase showed a single band on SDS-PAGE gel,and the molecular weight is about 25 KDa.2.The lipase activity were assayed by acid-base titration by diluting it to different multiple,and a more appropriate desaturation multiple:200 was determined.Its optional reactive temperature is about 60?,the optional reactive p H is 8.0.Under 60?,after 5 hours the relative activity of lipase is about 80%.The metal ions including Zn²⁺?Fe³⁺?Al³⁺?Ca²⁺?Cu²⁺?Mn²⁺?Cr³⁺can restrain the activity of lipase,while the Na⁺?K⁺?Mg²⁺can active the lipase activity.And the activity of lipase was strongly inhibited by SDS?HM A-474B?AEO-9?Tween-80 and 1227.Under suitable concentration,the lipase activity increased about 10%by JFC.3.The suitable modified process parameters are as follows:the enzyme dosage is about 10 g/L,JFC dosage is about 0.5 g/L,temperature is about 80?,pH is 8.0,and the reaction time is about7 hours.The weight loss rate of the polyester fabric treated by lipase decreased and the moisture regain increased about 0.17%,the hydrophilic property and antistatic property were both improved.No distinct surface etching was observed with SEM.4.Temperature,p H,metal ions,ultraviolet and organic solvent can effect the absorption spectra of Vio.After about 1 hour,the absorbance of Vio decreased about 76.9%at 120?130?.Color shade was stable at p H 4?8,the Vio will completely discoloration in the presence of Fe³⁺.The Abs of Vio decreased about 8%.After 6h under UV radiation.The organic solvent can affect the maximum absorption of Vio.5.The K/S values of nylon 6,silk,wool which dyed by Vio are better than those of cotton,flax and polyester fabrics.The suitable parameter of dyeing process of silk fabric are as follows:temperature is about 70?,the p H is 4?8,and the dyeing time is more than 60 min,the liquor ratio is about 1:50.The suitable parameter of dyeing process of nylon 6 are as follows:temperature is about 60?,p H is 2?8,the dyeing time is more than 60 min,the liquor ratio is about 1:100.The washing and rubbing fastness of dyed fabric is excellent,but the color fastness of light was only 1 grade.The inhibitory rate for S.aureus is about 81.25%,the UPF>40 and the T(UVA)<0.5%,when the silk fabric dyed with 5%(owf)Vio.6.The ascorbic acid can improve the color fastness to light of dyed silk fabric.The color fastness to light is 3?4 grade,when the dosage of ascorbic acid is about 50 g/L.