Enhancing antimicrobial properties of dyed and finished cotton fabrics

1,2,3-Benzothiazole-7-thiocarboxylic acid-S-methylester (commercially known as Actigard^® AM-87) was utilized to impart cotton fabric durable antimicrobial properties. Finishing treatment was carried out under a variety of conditions. The latter were included, effect of pH, concentration of antibacterial agents, curing temperature and curing time. The effect of fabric construction, mercerization, and dyeing with different dyestuff were also investigated. The study was also extended to investigate the technical feasibility of combining antimicrobial finishing treatment in question with other finishing treatment generally carried out on cotton fabric, like soft finishing and crease recovery finishing. The treated fabrics were monitored for antimicrobial properties before and after washing. The treated fabrics were also evaluated for the physio-mechanical properties like fabric tensile strength, elongation at break (or bursting strength for knitted fabric), wettability, crease recovery angle, whiteness index and roughness. Results obtained show that, the most appropriate conditions for treatment cotton fabric with Actigard^® are: padding the cotton fabric in aqueous solution containing 6% Actigard^® at pH 5 (adjusted using formic acid) then squeezed to wet pick up of 100%, dried at 80 °C for 5 min then cured at 100 °C for 150 s. The untreated cotton fabric did not show any antimicrobial activity towards Staphylococcus aureus or Escherichia coli. Treatment of cotton fabric with Actigard^® improves its antimicrobial properties towards S. aureus or E. coli. It is also observed that, treatment of cotton fabric with Actigard^® marginally decreases fabric tensile strength, elongation at break, roughness and WI, whereas; both wettability and crease recovery angle remain practically intact. This was observed whether the fabric was pre-mercerized or not.     

Chemical characteristics and antioxidant activity of exopolysaccharide fractions from Microbacterium terregens

The Gram-positive bacterial strain isolated from soil was identified as the non-pathogenic Microbacterium terregens. The exopolysaccharide (CPS) produced from M. terregens was obtained by isopropanol precipitation (13.72 g L^?1 growth medium), The resulted exopolysaccharide was purified by chromatography on DEAE-cellulose and Sephacryl S-200 columns, when two polysaccharide fractions termed CPSI and CPSII were obtained. Structure features of CPSI and CPSII were investigated by a combination of chemical and chromatographic analyses, such as acid hydrolysis, methylation analysis, periodate oxidation–Smith degradation, HPLC, GC–MS, and IR. The results indicated that CPSI and CPSII were composed of glucose: mannose in a ratio of 2.7:1 and 3.2:1 with molecular weights 80 and 150 kDa, respectively. It has a backbone of (1 → 4)-linked β-glucose residues, which occasionally branches at O-6. The branches were composed of (1 → 4)-linked β-mannose residues. The antioxidant activity of the CPS, CPSI and CPSII was evaluated in-vitro by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay (RSA). CPSI fraction showed the highest antioxidant activity among the three fractions, with an IC₅₀ value of 230 μg mL^?1. The effect of molecular weight of the polysaccharide on the improvement of the antioxidant potential seems to be significant.     

Structural characterization and surface activity of hydrophobically functionalized extracted pectins

The technological properties of pectins are generally influenced by their chemical modification. Thus, amidated pectins are important derivatives with good emulsifying properties at low concentrations. The present article focuses on the comparative study of physicochemical properties of three modified pectin derivatives. Various amphiphilic derivatives in which pectin is associated with hydrophobic amines chains were prepared. The reaction was carried out in heterogeneous medium in methanol at 20 °C for 7 days and with 0.5 pectin/alkylamine mass ratio. The degrees of amidation (DA) of the derivatives were calculated based on the results of FTIR spectroscopy. The surface-active properties of the modified pectins were determined by surface tension (air/water) and interfacial tension (oil/water) measurements. The aminolysis of pectins appears to be an interesting way to produce pectin derivatives with new properties able to stabilize oil-in-water emulsions.     

New development for combined bioscouring and bleaching of cotton-based fabrics

A thorough investigation into conditions appropriate for effecting combined eco-friendly bioscouring and/or bleaching of cotton-based fabrics was undertaken. Fabrics used include cotton, grey mercerized cotton, cotton/polyester blend 50/50 and cotton/polyester blend 35/65. The four cotton-based fabric were subjected to bioscouring by single use of alkaline pectinase enzymes or by using binary mixtures of alkaline pectinase and cellulase enzymes under a variety of conditions. Results of bioscouring show that, the bioscoured substrates exhibit fabrics performances which are comparable with these of the conventional alkali scouring. It has been also found that, incorporation of ethylenediaminetetraacetic acid (EDTA) in the bioscouring with mixture from alkaline pectinase and cellulase improves the performance of the bioscoured fabrics. Addition of β-cyclodextrin to the bioscouring solution using alkaline pectinase in admixtures with cellulase acts in favor of technical properties and performance of the bioscoured fabrics. Concurrent bioscouring and bleaching by in situ formed peracetic acid using tetraacetylethylenediamine (TAED) and H₂O₂ was also investigated. The results reveal unequivocally that the environmentally sound technology brought about by current development is by far the best. The new development involves a single-stage process for full purification/preparation of cotton textiles. The new development at its optimal comprises treatment of the fabric with an aqueous formulation consisting of alkaline pectinase enzyme (2 g/L), TAED (15 g/L), H₂O₂ (5 g/L), nonionic wetting agent (0.5 g/L) and sodium silicate (2 g/L). The treatment is carried out at 60 °C for 60 min. Beside the advantages of the new development with respect to major technical fabric properties, it is eco-friendly and reproducible. This advocates the new development for mill trials.     

Occurrence and Distribution of Microdochium and Fusarium Species Isolated from Durum Wheat in Northern Tunisia and Detection of Mycotoxins in Naturally Infested Grain

An outbreak of Fusarium Head Blight of durum wheat occurred in 2004 being localized in sub-humid and higher semi-arid region of Northern Tunisia. A mycological survey carried out throughout these regions, revealed that 78% of the prospected fields were infested. Results of the morphological and molecular identification, showed that the most common species isolated from diseased wheat spikes was Microdochium nivale var. nivale (63.5%), followed by Fusarium culmorum (26%), F. pseudograminearum (9%) and F. avenaceum (1.5%). To evaluate mycotoxin content of naturally infected grain, the amounts of trichothecene mycotoxin deoxynivalenol (DON) in harvested grain from 45 fields were quantified by RIDASCREEN DON Enzyme Immunoassay Kit (ELISA) . This study showed that the infection levels in freshly harvested grain were very low and the maximum deoxynivalenol (DON) level of the positive samples was 53 ppb. This is the first report on the natural occurrence of DON in naturally infected wheat grain sampled from Northern Tunisia.     

A randomized controlled trial to assess the safety and efficacy of silymarin on symptoms,signs and biomarkers of acute hepatitis

PurposeMilk thistle or its purified extract, silymarin (Silybum marianum), is widely used in treating acute or chronic hepatitis. Although silymarin is hepatoprotective in animal experiments and some human hepatotoxic exposures, its efficacy in ameliorating the symptoms of acute clinical hepatitis remains inconclusive. In this study, our purpose was to determine whether silymarin improves symptoms, signs and laboratory test results in patients with acute clinical hepatitis, regardless of etiology.MethodsThis is a randomized, placebo-controlled trial in which participants, treating physicians and data management staff were blinded to treatment group. The study was conducted at two fever hospitals in Tanta and Banha, Egypt where patients with symptoms compatible with acute clinical hepatitis and serum alanine aminotransferase (ALT) levels >2.5 times the upper limit of normal were enrolled. The intervention consisted of three times daily ingestion of either a standard recommended dose of 140 mg of silymarin (Legalon^®, MADAUS GmbH, Cologne, Germany), or a vitamin placebo for four weeks with an additional four-week follow-up. The primary outcomes were symptoms and signs of acute hepatitis and results of liver function tests on days 2, 4 and 7 and weeks 2, 4, and 8. Side-effects and adverse events were ascertained by self-report.ResultsFrom July 2003 through October 2005, 105 eligible patients were enrolled after providing informed consent. No adverse events were noted and both silymarin and placebo were well tolerated. Patients randomized to the silymarin group had quicker resolution of symptoms related to biliary retention: dark urine (p=0.013), jaundice (p=0.02) and scleral icterus (p=0.043). There was a reduction in indirect bilirubin among those assigned to silymarin (p=0.012), but other variables including direct bilirubin, ALT and aspartate aminotransferase (AST) were not significantly reduced.ConclusionsPatients receiving silymarin had earlier improvement in subjective and clinical markers of biliary excretion. Despite a modest sample size and multiple etiologies for acute clinical hepatitis, our results suggest that standard recommended doses of silymarin are safe and may be potentially effective in improving symptoms of acute clinical hepatitis despite lack of a detectable effect on biomarkers of the underlying hepatocellular inflammatory process.     

Spasmolytic and anti-inflammatory effects of constituents from Hertia cheirifolia

A sesquiterpenoid Bakkenolide (1), and two steroids, (3β, 22E)-Stigmasta-5, 22-diène-3-ol (Stigmasterol) (2) and stigmasterol 3β-glucoside (3), isolated from the Hertia cheirifolia (L.) chloroform extract, were evaluated respectively for their spasmolytic and anti-inflammatory activities. We note that these natural products were isolated and purified for the first time from the specie Hertia cheirifolia. Their structures have been established by spectroscopy (1 and 2D NMR experiences) and mass spectrometry. Chloroform-, ethyl acetate- and methanol-extracts were also tested for their spasmolytic and anti-inflammatory activities. Spasmolytic and anti-inflammatory screening were based respectively on the contractile response effects on rat isolated smooth muscles and on the dose-related carrageenan induced paw edema in rats. screening of the crude extracts showed spasmolytic and anti-inflammatory positive results. The antispasmodic effect of Bakkenolide was found in the same range as that of Alverine, a standard musculotropic spasmolytic agent.     

Cytohistological and phytochemical study of madder root extracts obtained by ultrasonic and classical extractions

Introduction – Madder (Rubia tinctorum) has been used since ancient times as a source of pigments for dyeing and painting. Madder dyes are localised in roots and the native chemical population is composed of glycosiled and aglycone compounds. The aim of this study is to elaborate an efficient extraction process without any chemical denaturation of dyes. Objective – To compare an optimised ultrasonic process, using for madder dye extraction, with two conventional procedures and to determine the efficiency of ultrasound on these vegetable matrix. Methodology – Madder roots were extract in a methanol–water mixture in 37 : 63 (v/v) for ultrasound and 80 : 20 (v/v) for reflux and agitation. HPLC‐PAD analyses showed the anthraquinone proportion for each extraction process and their denaturing effects. Finally, cytohistological observations were made to show the consequence of each process on the cell organisation in madder roots. Results – The results showed that the amount of extracted dyes was higher with UAE than with agitation and reflux. HPLC‐PAD analysis revealed that the anthraquinone composition differed according to the extraction procedure. The UAE extracts presented an important richness in terms of anthraquinonic compounds that suggests a preserving effect. Cytohistological observations showed that the main alterations concerned the cell walls of phloem. After UAE the walls exhibited numerous pitted areas reflecting an ultrasound‐induced cavitation that enhances the extraction effectiveness of this method. Conclusion – The study has shown the improvement of madder roots extraction both quantitatively and qualitatively using the efficiency of ultrasound‐assisted extraction in comparison with magnetic agitation and reflux techniques. Copyright © 2009 John Wiley & Sons, Ltd.     

Optimization of microporous palm shell activated carbon production for flue gas desulphurization: experimental and statistical studies

Optimizing the production of microporous activated carbon from waste palm shell was done by applying experimental design methodology. The product, palm shell activated carbon was tested for removal of SO2 gas from flue gas. The activated carbon production was mathematically described as a function of parameters such as flow rate, activation time and activation temperature of carbonization. These parameters were modeled using response surface methodology. The experiments were carried out as a central composite design consisting of 32 experiments. Quadratic models were developed for surface area, total pore volume, and microporosity in term of micropore fraction. The models were used to obtain the optimum process condition for the production of microporous palm shell activated carbon useful for SO2 removal. The optimized palm shell activated carbon with surface area of 973 m(2)/g, total pore volume of 0.78 cc/g and micropore fraction of 70.5% showed an excellent agreement with the amount predicted by the statistical analysis. Palm shell activated carbon with higher surface area and microporosity fraction showed good adsorption affinity for SO2 removal.     

Synthesis of potent antitumor and antiviral benzofuran derivatives

A new series of potent antitumor and antiviral benzofuran derivatives was synthesized by the reaction of the furochromone-6-carboxaldehydes 1 and 2 with different heterocyclic amines to yield the benzofuran-5-carbonyl derivatives 4–11. The synthesized compounds 1, 3–11 were tested against twelve different human cancer cell lines and all of the compounds were more potent than the comparative standards. The HIV inhibitory activity of the tested compounds 1, 3–11 showed that they have higher potency than Atevirdine. Moreover, compound 6 was significantly potent with wider therapeutic index. The HIV-1 RT inhibitory activity showed that compounds 10, 11, 3 and 4 were notably potent but with lower therapeutic index than Atevirdine. The HCV NS3-4A protease inhibitor activity of the tested compounds revealed that they have weaker potency and less therapeutic index than VX-950, although compounds 1, 4, 9 and 6, respectively exhibited significant activity.