Eco-Friendly Dyeing of Silk and Cotton Textiles Using Combination of Three Natural Colorants

Silk and cotton fabrics were dyed with combination of three colorants extracted from Acacia catechu (AC), Alkanna tinctoria (AT), and Curcuma Longa (CL) in nine different formulations at 80°C by exhaustion method without mordanting. Dyed samples were evaluated for color value and washing fastness. The biodegradability of dye bath effluent was assessed by measuring the pH, TDS and COD of the residual dye bath liquor. It is inferred that the final color of dyed fabrics from each formulation is governed by the dominant natural dye in the dyeing combination. K/S values inferred that the exhaustion of natural dye is higher in silk fabric than cotton fabric in all formulations. It could be concluded that in the dyeing combination, colorant that have very good affinity towards the functional groups of fibers, itself acts as mordant for other natural colorants.     

Dyeing Properties of Natural Dyes Extracted from the Junipers Leaves (J. excelsa Bieb. and J. oxycedrus L.)

In this paper, two natural dyes were extracted from Junipers leaves (Juniperus oxycedrus L. and Juniperus excelsa Bieb.). Wool yarn (for carpet) was dyed with the extract using ferrous (II) sulfate, potassium dichromate and sodium sulfate as mordant. Then, CIELab (L*, a*, b*, c,* and h) values, color differences (ΔE) and color strength (K/S) values of dyed wool yarns were examined and the fastness properties of dyed wool against dry and wet rubbing were evaluated. According to the experimental results, the use of mordant increased the color strength of dye goods. All mordant increased the rub fastness of dyed samples such as similar scientific studies previously. Compared to two junipers, dyeing samples of J. excelsa are dyed darker than that of J. oxycedrus.     

亚麻棉涂料浸染工艺研究(上)

对亚麻棉织物用涂料浸染方法进行工艺研究,选用了阳离子处理剂Hoe DP Fixer2LC和阳离子处理剂K2—76K对织物进行前处理,以改变纤维表面的带电性能,来吸附涂料粒子上染,对其上染性能、染色牢度、手感等性能进行研究。     

Identification of Irradiated Norway Lobster (Nephrops norvegicus) Using Electron Spin Resonance (ESR) Spectroscopy and Estimation of Applied Dose Using Re-irradiation: Results of an In-House Blind Trial

An in-house blind trial on Norway lobster (Nephrops norvegicus) was carried out in which 72 coded samples were correctly identified. The samples were either left unirradiated or had been given doses of 1·03, 2·39 or 3·40 kGy and stored for 0, 7 or 14 days at 1°C. Using re-irradiation, the doses received by the samples identified as irradiated were determined with either linear, quadratic or asymptotic equations being fitted to the data. The most successful estimates of absorbed dose were obtained using a quadratic fit, with average values of 1·71, 2·98 and 3·45 kGy being calculated. © 1997 SCI.     

环保型印染助剂发展方向探讨(上)

印染助剂是纺织品生产必需的化学品之一。我国是纺织品生产大国,并正在为提高纺织品附加价值而努力,研究和开发新的印染助剂是一个重要的途径。开发环保型印染助剂,与开发节约型和创新型印染助剂同为发展目标,同时也顺应当前消费和出口需要。文章提出国内外开发的一些助剂品种．并提出如何正确认识某些生态纺织品环保法规。     

Dyeing of silk fabric with natural dyes extracted from cochineal (Dactylopius coccus Costa) and gall oak (Quercus infectoria Olivier)

Silk fabric samples were mordanted with alum [KAl(SO₄)₂.12H₂O]. Then, the samples were dyed with cochineal (Dactylopius coccus Costa) and gall oak (Quercus infectoria Olivier) shellac extracts. Optimum dyeing parameters were determined by using different concentrations of these natural colorants. All the dyed samples were cut into two equal pieces. One group of the parts were post-mordanted with FeSO₄. A reserved-phase high-performance liquid chromatography (RP-HPLC) with the diode-array detection (DAD) method was utilized for the identification of the components of dyes present in the all dyed and post-mordanted samples. The color coordinates and fastness values of washing, perspiration, rubbing, and light were investigated and compared with each other. Using a mixture of these natural dyes enhanced the exhaustion of the dye and good color fastness test results were achieved.     

AB-8型大孔吸附树脂分离纯化了哥王总黄酮

通过考察各种因素对树脂吸附和洗脱效果的影响,确定AB-8型大孔吸附树脂分离纯化了哥王总黄酮的最佳工艺参数。最佳工艺参数为上样液浓度1.5 mg/mL、上样液流速2 BV/h、上样液pH 5.4、洗脱液浓度70%乙醇、洗脱液流速1 BV/h和洗脱液用量为80 mL,分离纯化后的总黄酮产品纯度可达20.60%。     

Poly(Acrylic Acid)-Starch Composites. A Key for Improving Sizeability and Desizeability of Starch from Cotton Textiles

Maize and rice starches were independently polymerized with acrylic acid (AA) using potassium permanganate/citric acid initiation system. The dependence of total conversion (grafting and homopolymerization) on AA, potassium permanganate and citric acid concentrations, time and temperature of polymerization and rate of stirring were studied. Based on the results appropriate conditions for preparation of poly(AA)-starch composites were established. While the total conversion increased by increasing AA concentration from 10% to 30%, based on weight of starch (ows), maximum total conversion occured upon using 0,2% potassium permanganate along with 0.025% citric acid, ows, for 10 min at 40°C and stirring rate of 300 r. p. m. It was further disclosed that: (a) the total conversion for maize starch is higher than rice starch, (b) the apparent viscosity of the composite increases by increasing AA concentration from 10% to 30% and polymerization temperature from 30°C to 50°C, (c) for 10% AA concentration the composite consists of 97.67 starch and 2.33% poly-(AA) of which 1.36% is grafted whereas for 30% AA concentration the composite consists of 79.3% starch and 20.7% poly(AA) of which 3.2% is grafted, (d) the sizeability of native starches is considerably improved after polymerization with AA and (e) size removal from cotton fabric with the composites to ca. 80% while wize removal from cotton fabric sized with native starches amounts to ca. 20%.     

The aminopeptidase C (PepC) from Lactobacillus helveticus CNRZ32. A comparative study of PepC from lactic acid bacteria

 The aminopeptidase C (PepC) of Lactobacillus helveticus CNRZ32 was purified by anion exchange chromatography from cell free extracts of an E. coli DH5α clone overexpressing the Lactobacillus aminopeptidase. PepC was found to have a tetrameric structure in its native form with subunits of 50 kDa each, a pH optimum of 6.5 and maximum activity at 45  °C. Sulfhydryl-blocking reagents inhibited the enzyme activity whereas reducing or metal chelating reagents had an activating effect on the PepC activity. The PepC hydrolyzed a wide range of p-nitroaniline derivatives, dipeptides and several tripeptides which contained basic amino acids (Arg, Lys), Pro residues, or cheese flavour precursor amino acids (Met, Leu, Phe) at the N-terminal position. The substrate specificity and residual activity of PepC from several lactic acid bacteria, including the PepC described above, were compared at conditions of pH and NaCl present in cheese. Received: 25 February 2000     

响应面分析法优化肉苁蓉多糖提取反应的研究

研究提取肉苁蓉多糖的最优工艺条件.选用提取时间、提取温度、提取固液比3个反应因素作为研究对象,以多糖提取率为考察指标,通过响应面分析方法优化肉苁蓉多糖的提取工艺条件.实验结果表明.最优工艺条件为提取时间 193.0 min、温度 94.59℃、固液比 10.89,多糖提取率的理论值为 85.5%.     

正交试验法优化香柏(变种)中总黄酮提取工艺

研究提取香柏总黄酮的最佳工艺条件。以总黄酮的得率为考察指标,溶剂回流作为提取手段,利用单因素和正交试验,考察提取温度、提取时间、乙醇溶液体积分数、液固比以及提取次数对总黄酮得率的影响。最优工艺条件为:在80℃水浴条件下,提取时间90 min、乙醇溶液体积分数60%、液固比50∶1(mL/g)、提取次数3次。在最优工艺条件下总黄酮的提取率可达7.68 g/100 g。该方法操作方便、准确可靠,可以用于工业化生产。     

Melittis melissophyllum L. subsp. melissophyllum (Lamiaceae) from central Italy: A new source of a mushroom-like flavour

1-Octen-3-ol is the most important C8 mushroom aromatic compound produced by many species of edible fungi and is also an aroma component in several food and beverages products. Under this view, the essential oil of flowering aerial parts of Melittis melissophyllum subsp. melissophyllum (Lamiaceae) growing in central Italy, obtained by hydrodistillation was characterised by GC–FID and GC–MS. This oil contained extremely high amount of the mushroom-like aroma component 1-octen-3-ol (43.6–54.2%), and could be considered as a new natural product for the use as flavouring agent in the food industry. Furthermore, headspace analysis suggested that this aromatic compound is only present in low concentration in the plant part, and is primarily formed in higher amount during hydrodistillation of this material.     

A U.S. population dietary exposure assessment for 4-methylimidazole (4-MEI) from foods containing caramel colour and from formation of 4-MEI through the thermal treatment of food

ABSTRACT

4-Methylimidazole (4-MEI) is formed in caramel colours produced using ammonium compounds (Class III and Class IV caramel colours). 4-MEI can also form in food through Maillard reactions between reducing sugars and amino acids during cooking, roasting or dry-heating. The USFDA has analysed over 700 food and beverage samples collected from 2013 to 2015 for the presence of 4-MEI. These samples include foods containing added caramel colour and foods that are not labelled as containing added caramel colour, but which may contain 4-MEI resulting from thermal treatment. The 4-MEI levels in all food samples were quantified using LC-MS/MS. These data were used to develop a comprehensive dietary exposure assessment for 4-MEI for the U.S. population aged 2 years or more and several sub-populations, using two non-consecutive days of food consumption data from the combined 2009–2012 National Health and Nutrition Examination Survey and 10–14-day food consumption survey data for 2009–2012 from the NPD Group, Inc. National Eating Trends–Nutrient Intake Database. Dietary exposure estimates were prepared for each category of foods labelled as containing added caramel colour and of foods not labelled as containing added caramel colour, but which may contain 4-MEI from thermal treatment. Exposure to 4-MEI from consumption of foods containing added caramel colour was higher than that from foods that contain 4-MEI from thermal treatment for all population groups. Cola-type carbonated beverages were the highest contributors for most populations from foods containing added caramel colour. Coffee was the highest contributor for most populations from foods in which 4-MEI could be formed from thermal treatment. An overall combined exposure to 4-MEI was also estimated that included all foods identified as containing added caramel colour and foods in which 4-MEI could be formed by thermal treatment.     

Cloning and expression of the gene encoding the thermophilic NAD(P)H-FMN oxidoreductase coupling with the desulfurization enzymes from Paenibacillus sp. A11-2

The gene encoding the NAD(P)H-flavin oxidoreductase (flavin reductase) which couples with the thermophilic dibenzothiophene (DBT)-desulfurizing monooxygenases of Paenibacillus sp. A11-2 was cloned in Escherichia coli and designated tdsD. Nucleotide sequence analysis suggested that the gene product consisted of 200 amino acids and showed about 30%, 27% and 26% amino acid sequence similarity to the major flavin reductase of Vibrio fischeri, the NADH dehydrogenase of Thermus thermophilus and several oxygen-insensitive NAD(P)H nitroreductases in the Enterobacteriaceae family, respectively. Both the growing and resting recombinant E. coli, in which tdsD was coexpressed with a set of desulfurizing genes, showed a rate of DBT removal about 5 times higher than the recombinants lacking tdsD. Maximal desulfurization was observed close to 45°C and 55°C in the resting cells and in the cell-free extraction reaction with the tdsD-coexpressing recombinants, respectively. In an organic/aqueous biphasic system, the coexpression of tdsD also markedly enhanced the rate of DBT removal.