Quantitative structure-activity relationship study on the biodegradation of acid dyestuffs

Quantitative structure-biodegradability relationships （QSBRs） were established to develop predictive models and mechanistic explanations for acid dyestuffs as well as biological activities. With a total of four descriptors, molecular weight （MW）, energies of the highest occupied molecular orbital （EHOMO）, the lowest unoccupied molecular orbital （ELUMO）, and the excited state （EES）, calculated using quantum chemical semi-empirical methodology, a series of models were analyzed between the dye biodegradability and each descriptor. Results showed that EHOMO and Mw were the dominant parameters controlling the biodegradability of acid dyes. A statistically robust QSBR model was developed for all studied dyes, with the combined application of EHOMO and Mw. The calculated biodegradations fitted well with the experimental data monitored in a facultative-aerobic process, indicative of the reliable prediction and mechanistic character of the developed model.

Union Dyeing Behavior on the Blends of Tencel and Shrink-proofing Wool with the Same Reactive Dyestuffs in One Bath

In order to obtain union colour on the blends of Tencel and shrink-proofing wool and improve the efficiency of dyeing process, the dyeing behavior on the blends of Tencel and shrink-proofing wool in the same bath was studied. The Argazol TW reactive dyestuffs were involved in the dyeing process. The parameters under different conditions such as exhaustion, fixation,compatibility as well as soaping fastness were investigated in detail. It is shown that the Argazol TW reactive dyestuffs are suitable for dyeing of blends of Tencel and shrink-proofing wool and good dyeing behavior can be expected.

利用玉米棒对纺织废水进行吸附脱色的研究

本文研究了玉米棒对两种碱性染料Astrazon Blue和Maxilon Red以及两种酸性染料Telon Blue和Erionyl Red的吸附效果。研究表明,玉米棒对碱性染料Atrazon Blue和Maxilon的吸附容量较高,分别为:160mg/g、94.5mg/g;对酸性染料Telon Blue和Erioyl Red的吸附容量较低,分别为:47.7mg/g、41.4mg/g。在间歇式搅拌吸附器中进行恒定时间实验,首先观察系统内各变量:即搅拌速度、玉米棒颗粒的大小及玉米棒的质量的作用,然后对实验的结果进行分析、讨论。

Polymorphism of N-acetyltransferase 2 (NAT2) Gene Polymorphism in Shanghai population: Occupational and Non-occupational Bladder Cancer Patient Groups

Objective Arylamine N-acetyltransferases (NATs) are involved in the detoxification of aromatic amines and hydrazine. In order to explore the possible association of NAT2 polymorphism with bladder cancer risk in benzidine exposed or non-exposed Chinese individuals, healthy subjects, subjects with bladder cancer of a former benzidine exposed cohort in Shanghai dyestuff industry and a group of bladder cancer patients without known occupational exposure to aromatic amines were genotyped for NAT2 gene polymorphism. Methods NAT2 genotyping was performed with a set of RFLP procedures at seven major polymorphic loci of gene coding area: G191A, C282T, T341C, C481T, G590A, A803G and G857A. Results The wild allele NAT2 *4 was the most prevalent allele (59%) in healthy individuals. The alleles NAT2*6A and NAT2*7B were also frequently observed (21% and 17%, respectively). In contrast to Caucasians, the percentage of slow acetylators was lower (12% in Chinese vs. 58% in Caucasians, P<0.001). No relevant differences were observed for homogenous rapid, heterogeneous rapid/slow and homogeneous slow acetylation genotypes between the healthy subjects and both groups of bladder cancer patients. Conclusion The present work did not support the association of slow acetylating genotypes of NAT2 gene with elevated risk of bladder cancer in Chinese whereas it was documented as an important genetically determined risk factor in Caucasians. Different mechanisms might play a role in individual susceptibility to bladder cancer related with aromatic amine exposure in various races or ethnic groups.

THE EFFECTS OF PLASMA-INDUCED GRAFT COPOLYMERIZATION WITH ACRYLIC ACID ON THE STRUCTURE AND DYEING PROPERTIES OF MULBERRY SILK

The effects of plasma-induced graft copolymerization with acrylic acid (AAc) on the structure and dyeing properties of mulberry silk are investigated. Through the transmission infrared spectroscopy(IR) , attenuated total reflection infrared spectroscopy(ATR-IR) and X-ray photoelectron spectroscopy(XPS) studies, changes of the surface structure and composition are observed. The results show that plasma-induced graft copolymerization has a different meehanism from that of chemical graft copolymerization. The plasma graft copolymerization brings AAc branch polymers into the surface of silk through the initiation of some kinds of oxygen and nitrogen groups created by plasma. That is just the reason that the dyeing ability and color fastness of plasma-grafted silk for cationic dyestuff increase and its mechanical properties have not been changed significantly.

Relationships between Species of Dyestuff Precursor and Dyeability in Hair Colouring Made by Enzymatic Oxidation Technique Using Bio-Catechols

In the study, hair colouring by utilising enzymatic oxidation of nine species of bio-catechols, which are biobased materials having the catechol (o-dihydroxybenzene) group, was examined. The bio-catechols used are (+)-catechin (Cat), (-)-epicatechin (EC), L-3,4-dihydroxyphenylalanine (DOPA), hematoxylin (HX), brazilin (BZ), rosmarinic acid (RA), caffeic acid (CA), chlorogenic acid (ChA) or ellagic acid (EA). The dyeability of human white hair samples dyed by two kinds of dyeing methods using the bio-catechols was compared. First one is dyeing hair during the enzymatic oxidation of a bio-catechol dye precursor in a dye solution (simultaneous oxidation dyeing method). Second one is dyeing hair by oxidising enzymatically the precursor on hair, which is pre-treated with a bio-catechol solution (post-oxidation dyeing method). The results show that the bio-catechols except EA are oxidised to give colourants and Cat, EC, DOPA, HX and BZ are available for hair dyeing. Overall, the dyeability of simultaneous oxidation dyeing method is higher than that of post-oxidation one. The colour of the hair dyed by simultaneous method is yellowish brown for Cat or EC, grey for DOPA, dark yellowish brown for HX or reddish brown for BZ, respectively. The most vivid or deepest colour of dyed hair is obtained by dyeing with Cat or HX, respectively, in the simultaneous technique. It was found that the bio-catechols having chroman (3, 4-dihydro-2H-1-benzopyran) structure in the molecule such as Cat, EC, HX and BZ are useful for hair colouring.

Evaluation of Economical and Ecological Aspects of Denim Garments Dyeing with Fluorescent Dye

In this study the existing process (3 steps) and proposed process (2 steps) were evaluated during dyeing of denim fabric with fluorescent dye. It compared the effectiveness of these two processes of fluorescent dyeing in the textile industry. Here at first the grey denim fabric was pretreated by scouring and bleaching. Then the fabric was dyed in existing process i.e. through catanizing, dyeing and binding at 10% and 15% shades. Again the pretreated fabric was dyed in proposed process i.e. through catanizing and (dyeing and binding) with same shades. Then the properties of two types of dyed fabric were compared. This study provides a set of experimental results, discussion and comparison between the two processes. The results show that the proposed process has less power and time consumption and more water savings compared to existing process. So the evaluation reflected that the proposed process was much more effective than existing process of denim dyeing with fluorescent dye.

Looking for Chinese Red:Materia Medica Trade along the Silk Road and Development of Chinese Red Dyestuff

In thousands of years from the Pre-Qin Dynasty to the Qing Dynasty,crimson represents sacredness and good fortune in several dynasties and is honored in the hierarchy of colors.Meanwhile,introduction to the exotic Materia Medica for dyeing from the Silk Road trade greatly expands the dyeing category of red color.The exotic red dyestuff is eventually integrated into the red culture of the Central Plains through the localization process.Therefore,it becomes the color symbol on behalf of Chinese nation.

Relationship between Dyeing Condition and Dyeability in Hair Colouring by Using Catechinone Prepared Enzymatically or Chemically from (+)-Catechin

Hair colouring was carried out by using catechinone prepared from (+)-catechin by enzymatic or chemical oxidation reaction. The difference of dyeability between the catechinone produced by enzymatic reaction (EC) and that produced by chemical reaction (CC) was studied changing the dyeing condition such as dye concentration, dyeing temperature, pH or the sort and concentration of salts. The colour of the hair dyed by EC or CC at 30°C is yellowish or reddish brown, respectively. The colour of the hair dyed by EC and CC is deeper at a higher dye concentration and at a higher temperature. Hair is dyed deepest by EC or CC at the solution pH = 6.04 or 5.45, respectively. The dyeability is increased by adding NaCl (≤4 M) or CaCl2 (≤1 M), while it is decreased by adding AlCl3. The colour fastness of the dyed hair to washing or ultraviolet light is high enough for practical use. Furthermore, it was found that colourants are obtained from tea extracts which contain catechin derivatives. Hair is dyed reddish brown by the colourants.

Hair Dyeing by Using Catechinone Obtained from (+)-Catechin

A novel colourant for hair dyeing was prepared by an enzymatic reaction with (+)-catechin and its characteristics as a hair dyestuff were studied. The study is aimed at inventing the hair dyestuff that is human- and eco-friendly. One potentially powerful dyestuff was obtained from (+)-catechin treated with tyrosinase after screening experiments using biobased materials. The obtained reddish orange colourant, 4-(3,4-dihydro-3α,5,7-trihydroxy-2H-1-benzopyran-2α-yl) 1,2-benzoquinone named “catechinone”, shows enough dyeability for decolourised white hair. Catechinone does not cause erythema or oedema on skin of rabbits. The colour is controlled by the addition of other biobased materials and a variety of colours of dyed hair are acquired. The fastness to light or washing for hair dyed by catechinone is high enough for practical use.

Effect of Reaction Conditions on Production of Catechinone Hair Dyestuff in Water/Alcohol Mixed Solution

Catechinone hair dyestuff was produced chemically from (+)-catechin by the oxidation with O2 in basic water/alcohol mixed solution. The effects of reaction conditions such as basicity, sorts of added base, temperature, alcohol molar fraction of solvent and sorts of added alcohols on the catechinone formation were studied in order to increase the efficiency of the dyestuff production. The amount of obtained catechinone increases with increasing basicity of the reaction solution. The dyestuff is obtained by adding monoethanol amine, diethanol amine, triethanol amine, l-arginine, Na2CO3, K2CO3, Na3PO4 or NaOH into the solution as a base and the most preferable base is monoethanol amine. The optimum temperature for the production in water/ethanol solution is 30&deg;C. It was found that water-soluble alcohols such as methanol, ethanol, 2-propanol, 1-propanol and tert-butyl alcohol are available for preparing the dyestuff. The optimum alcohol molar fraction of the mixed solvent used for the dye formation is 0.45 for methanol, 0.25 for ethanol and 0.20 for 2-propanol, 0.15 for 1-propanol and 0.10 for tert-butyl alcohol. The amount of the obtained dyestuff reaches a maximum at 1) 0.35 and 0.59, 2) 0.35 or 3) 0.35 mol&middot;kg¨1 of the concentration of (+)-catechin for the 1) water/methanol, 2) water/ethanol or 3) water/1-propanol system, respectively.

Dyeing Fabrics by Using Extracts from Mulberry Branch/Trunk 1.Dyeability and Fluorescence Property

The dyeing of wool, silk, cotton, ramie, nylon, acrylic and polyester fabric by using the extracts from mulberry branches and trunks was tried and the dyeability was studied. While the dyeability of the ethanol-extracts from mulberry is low, that of the water-extracts is high for wool, nylon and silk fabrics. They are dyed brownish and yellowish colours. The obtained colours depend on the extracts concentration in the dye solution, dyeing time, dye solution pH and dyeing temperature. Wool, nylon and silk fabrics are dyed deeper with an increase in the dyeing temperature. The mulberry extracts show fluorescence and reducing property. The results indicate that the mulberry extracts contain flavonols such as morin, kaempferol or quercetin, which form complexes with Al3+ and show fluorescence. The wool treated with the mulberry extracts or AlCl3/mulberry extracts shows fluorescence with ultraviolet light irradiation.

Enzymatic synthesis of indigo derivatives by tuning P450 BM3 peroxygenases

Indigoids,a class of bis-indoles,have long been applied in dyeing,food,and pharmaceutical industries.Recently,interest in these‘old’molecules has been renewed in the field of organic semiconductors as functional building blocks for organic electronics due to their excellent chemical and physical properties.However,these indigo derivatives are difficult to access through chemical synthesis.In this study,we engineer cytochrome P450 BM3 from an NADPH-dependent monooxygenase to peroxygenases through directed evolution.A select number of P450 BM3 variants are used for the selective oxidation of indole derivatives to form different indigoid pigments with a spectrum of colors.Among the prepared indigoid organic photocatalysts,a majority of indigoids demonstrate a reduced band gap than indigo due to the increased light capture and improved charge separation,making them promising candidates for the development of new organic electronic devices.Thus,we present a useful enzymatic approach with broad substrate scope and cost-effectiveness by using low-cost H2O2 as a cofactor for the preparation of diversified indigoids,offering versatility in designing and manufacturing new dyestuff and electronic/sensor components.

Synthesis and characterization of azo dyestuff based on bis(2-hydroxyethyl) terephthalate derived from depolymerized waste poly(ethylene terephthalate) fibers

This work aimed at effectively utilizing the chemically depolymerized waste poly（ethylene terephthalate）（PET） fibers into useful products for the textile industry.PET fibers were glycolytically degraded by excess ethylene glycol as depolymerizing agent and zinc acetate dihydrate as catalyst.The glycolysis product,bis（2-hydroxyethyl） terephthalate（BHET）,was purified through repeated crystallization to get an average yield above 80%.Then,BHET was nitrated,reduced,and azotized to get diazonium salt.Finally,the produced diazonium salt was coupled with 1-（4-sulfophenyl）-3-methyl-5-pyrazolone to get azo dyestuff.The structures of BHET and azo dyestuff were identified by FT1 R and ^1H NMR spectra and elemental analysis.Nylon filaments dyed by the synthesized azo dyestuff with the dye bath pH from 4.14 to 5.88 showed bright yellow color.The performances of the dyestuff were described with dye uptake,color fastness,K/S,L^＊,a^＊,b^＊.and △E^＊ values.

SYNTHESIS AND CHARACTERIZATION OF A NEW DYESTUFF POLYMER SOLUBLE IN ALKALINE AQUEOUS MEDIA

Novel dyestuff polymers were successfully obtained through oxidative polymerization technique. The synthesized Schiff base and its polymer were soluble in alkaline＇aqueous medium and they have various colors in different solutions. Also, it can be said that the synthesized compounds are suitable as coloring agent （dyestuff） for textile applications. Fluorescence properties of the compounds were determined in DMF with different concentrations （mg/L）. Poly-tris（4- aminophenyl）methanol （P-TAPM） has quite high emission and excitation intensity values. Optical and electrochemical band gaps of the polymers were lower than those of the monomers indicating the more conjugated structure of the polymers. The oxidized states of the novel dyestuff compounds were examined by cyclic voltammetry （CV） technique. The solid state conductivity measurements showed that the synthesized polymers were semiconductors when exposed to the iodine vapour their conductivities could be increased. P-TAPM had the highest undoped conductivity. Thermal characterizations of the synthesized compounds were carried out by TG-DTA and DSC methods.