Decolorization and detoxification of different azo dyes by Phanerochaete chrysosporium ME-446 under submerged fermentation.

Azo dyes are widely used in the textile industry due to their resistance to light, moisture, and oxidants. They are also an important class of environmental contaminant because of the amount of dye that reaches natural water resources and because they can be toxic, mutagenic, and carcinogenic. Different technologies are used for the decolorization of wastewater containing dyes; among them, the biological processes are the most promising environmentally. The aim of this study was to evaluate the potential of Phanerochaete chrysosporium strain ME-446 to safely decolorize three azo dyes: Direct Yellow 27 (DY27), Reactive Black 5 (RB5), and Reactive Red 120 (RR120). Decolorization efficiency was determined by ultraviolet-visible spectrophotometry and the phytotoxicity of the solutions before and after the fungal treatment was analyzed using Lactuca sativa seeds. P. chrysosporium ME-446 was highly efficient in decolorizing DY27, RB5, and RR120 at 50 mg L-1, decreasing their colors by 82%, 89%, and 94% within 10 days. Removal of dyes was achieved through adsorption on the fungal mycelium as well as biodegradation, inferred by the changes in the dyes' spectral peaks. The intensive decolorization of DY27 and RB5 corresponded to a decrease in phytotoxicity. However, phytotoxicity increased during the removal of color for the dye RR120. The ecotoxicity tests showed that the absence of color does not necessarily translate to an absence of toxicity.

Ecotoxicological risk assessment of the "Acid Black 210" dye.

The "Acid Black 210" dye is one of the most used black dyes by the leather industry. This compound contains three azo groups in its chemical structure, and has been quoted as a non-regulated dye with toxicological concern, since it could generate carcinogenic aromatic amines. The objective of this study was to perform the ecotoxicological risk assessment of this dye through testing its toxicity in vitro and in vivo with the Ames test, the Comet assay, the Daphnia similis test, and the zebrafish embryo acute toxicity test. Moreover, we evaluated the presence of this dye in environmental samples related with a tannery industry. All the tests performed were negative, with the exception of the Ames test with the Salmonella typhimurium TA98 strain, which resulted in a low mutagenic potency. Due to the low concentrations of the "Acid Black 210" dye found in tannery effluents, and the high concentrations where any toxic activity is occasionally described, we concluded that this dye is safe from the ecotoxicological point of view in the areas evaluated and in the light of the current knowledge.

A novel poly-naphthol compound ST104P suppresses angiogenesis by attenuating matrix metalloproteinase-2 expression in endothelial cells.

Angiogenesis, the process of neovascularization, plays an important role in physiological and pathological conditions. ST104P is a soluble polysulfated-cyclo-tetrachromotropylene compound with anti-viral and anti-thrombotic activities. However, the functions of ST104P in angiogenesis have never been explored. In this study, we investigated the effects of ST104P in angiogenesis in vitro and in vivo. Application of ST104P potently suppressed the microvessels sprouting in aortic rings ex vivo. Furthermore, ST104P treatment significantly disrupted the vessels' development in transgenic zebrafish in vivo. Above all, repeated administration of ST104P resulted in delayed tumor growth and prolonged the life span of mice bearing Lewis lung carcinoma. Mechanistic studies revealed that ST104P potently inhibited the migration, tube formation and wound closure of human umbilical endothelial cells (HUVECs). Moreover, ST104P treatment inhibited the secretion and expression of matrix metalloproteinase-2 (MMP-2) in a dose-dependent manner. Together, these results suggest that ST104P is a potent angiogenesis inhibitor and may hold potential for treatment of diseases due to excessive angiogenesis including cancer.

Bacterial assisted phytoremediation for enhanced degradation of highly sulfonated diazo reactive dye.

PURPOSE: Phytoremediation is the exploitation of plants and their rhizospheric microorganisms for pollutants treatment like textile dyes, which are toxic, carcinogenic and mutagenic from the effluent. The purpose of this work was to explore a naturally found plant and bacterial synergism to achieve an enhanced degradation of Remazol Black B dye (RBB). METHODS: In vitro cultures of Zinnia angustifolia were obtained by seed culture method. Enzymatic analysis of the plant roots and Exiguobacterium aestuarii strain ZaK cells was performed before and after decolorization of RBB. Metabolites of RBB formed after its degradation were analyzed using UV-Vis spectroscopy, high-performance liquid chromatography (HPLC), Fourier transform infrared (FTIR) and gas chromatography-mass spectrometry (GC-MS). Phytotoxicity studies were performed. RESULTS: The consortium ZE was found to be more efficient than individual plant and bacteria. Z. angustifolia roots showed significant induction in the activities of lignin peroxidase, laccase, DCIP reductase and tyrosinase during dye decolorization. E. aestuarii showed significant induction in the activities of veratryl alcohol oxidase, azo reductase and DCIP reductase. Analysis of metabolites revealed differential metabolism of RBB by plant, bacteria and consortium ZE. E. aestuarii and Z. angustifolia led to the formation of 3,6-diamino-4-hydroxynaphthalene-2-sulfonic acid, (ethylsulfonyl)benzene, and 3,4,6-trihydroxynaphthalene-2-sulfonic acid and propane-1-sulfonic acid, respectively, whereas consortium ZE produced 4-hydroxynaphthalene-2-sulfonic acid, naphthalene-2-sulfonic acid and 4-(methylsulfonyl)phenol. The phytotoxicity study revealed the nontoxic nature of the metabolites formed after dye degradation. CONCLUSION: Consortium ZE was found to be more efficient and faster in the degradation of RBB when compared to degradation by Z. angustifoila and E. aestuarii individually.

Effective and specific inhibition of the CD40-CD154 costimulatory interaction by a naphthalenesulphonic acid derivative.

Costimulatory interactions are important regulators of T-cell activation and, hence, promising therapeutic targets in autoimmune diseases as well as in transplant recipients. Following our recent identification of the first small-molecule inhibitors of the CD40-CD154 costimulatory protein-protein interaction (J Mol Med 87, 2009, 1133), we continued our search within the chemical space of organic dyes, and we now report the identification of the naphthalenesulphonic acid derivative mordant brown 1 as a more active, more effective, and more specific inhibitor. Flow cytometry experiments confirmed its ability to concentration-dependently inhibit the CD154(CD40L)-induced cellular responses in human THP-1 cells at concentrations well below cytotoxic levels. Binding experiments showed that it not only inhibits the CD40-CD154 interaction with sub-micromolar activity, but it also has considerably more than 100-fold selectivity toward this interaction even when compared to other members of the tumor necrosis factor superfamily pairs such as TNF-R1-TNF-α, BAFF-R(CD268)-BAFF(CD257/BLys), OX40(CD134)-OX40L(CD252), RANK(CD265)-RANKL(CD254/TRANCE), or 4-1BB(CD137)-4-1BBL. There is now sufficient structure-activity relationship information to serve as the basis of a drug discovery initiative targeting this important costimulatory interaction.

Acid violet 7 and its biodegradation products induce chromosome aberrations, lipid peroxidation, and cholinesterase inhibition in mouse bone marrow.

INTRODUCTION: Acid violet 7 (AV7), mostly used in food, paper, cosmetic, and especially in textile industries, was degraded by Pseudomonas putida mt-2 at concentrations up to 200 mg/l. MATERIALS AND METHODS: In this study, toxicity of AV7, before and after biodegradation, was evaluated in vivo, in mouse bone marrow, by assessing the percentage of cells bearing different chromosome aberrations, membrane lipid peroxidation, and acetylcholinesterasic activity inhibition. The studies included same conditions for animal treatment, corresponding to increasing doses by intraperitoneal (ip) injection. RESULTS: Results indicated that AV7 showed a significant ability to induce chromosome aberrations, lipid peroxidation, and acetylcholinesterase inhibitory effect. The toxicity of AV7 increased significantly after static biodegradation with P. putida mt-2 and totally disappeared after shaken incubation. In addition, the toxicity generated by the pure azo dye and the corresponding azoreduction metabolites (4'-aminoacetanilide (4'-AA) and 5-acetamido-2-amino-1-hydroxy-3,6-naphtalene disulfonic acid (5-ANDS)) were compared. 4'-AA and 5-ANDS would be responsible of static biodegradation medium toxicity. The present study demonstrates that P. putida mt-2, incubated under aerobic condition, has a catabolism which enables it to degrade AV7, and especially to completely detoxify the dye mixture.

Effects of candidate vaginally-applied microbicide compounds on innate immune cells.

Ideally, a vaginally-applied microbicide would be effective against a broad range of pathogens but would have minimal effects on the female genital tract. The aim of this study was to determine if representative candidate detergent-type and sulfated/sulfonated polymer-type microbicides altered the composition or function of innate immune cells normally found in the vaginal mucosa. The effect of microbicide on the composition of vaginal leukocytes was tested using a flow cytometric approach. Application of the detergent cholic acid, but not the sulfated polysaccharide lambda carrageenan, resulted in a significant increase in macrophages at the vaginal epithelial surface compared to control treatment (19.3% macrophages compared to 2.8%; p<0.0004). Phagocytosis of fluorochrome-labeled bacteria by macrophages was inhibited greater than 50% in the presence of 1.0mg/ml of the sulfonated polymer PRO 2000 but was not inhibited by the same concentration of lambda carrageenan. PRO 2000-pulsed macrophages regained phagocytic function after being washed free of the compound. Culture of macrophages with PRO 2000 also resulted in diminished detection of the surface proteins CD11b and CD18. After treated cells were washed free of PRO 2000, these proteins were detected at levels similar to control treated cells. In conclusion, application of a detergent-type microbicide, but not a sulfated polymer, resulted in the infiltration of inflammatory cells at the vaginal epithelial surface. Phagocytic function of macrophages was lost in the presence of 1mg/ml PRO 2000 which may have reflected masking of important cell surface proteins by the microbicide; however, there was no evidence of permanent loss of function upon removal of the compound.

Final report on the amended safety assessment of sodium polynaphthalenesulfonate and sodium naphthalenesulfonate.

Sodium Polynaphthalenesulfonate (SPNS) and Sodium Naphthalenesulfonate (SNS) are sodium salts of naphthalene sulfonic acid. SPNS was used as an emulsion stabilizer, surfactant--hydrotrope, and/or surfactant--suspending agent at concentrations between 0.1% and 0.4%, in a wide range of products, including one lipstick. SNS is described as a surfactant--hydrotrope; no current uses were reported, but information was provided indicating that use concentrations would be typically below 2%. SNS is manufactured by reacting naphthalene with sulfuric acid to produce a sulfonic acid, which is then reacted with sodium hydroxide to produce the final product. The polymer form uses the sulfonic acid intermediate in a reaction with formaldehyde and water under conditions of heat and pressure to form the polymer sulfonic acid form, to which sodium hydroxide is added to make the final SPNS. The residue level of formaldehyde was 0.09%. Only around 1% of SNS in a 1-mg/ml solution applied to porcine skin penetrated the skin after 24 h, a similar amount was found noncovalently bound to the skin, and the concentration of material applied to the surface of the skin was largely unchanged. Both chemicals were not toxic in acute oral or dermal studies. In a subchronic oral toxicity study in rats, the effects noted were increases in urinary sugar in females and urine protein concentrations in males. Although undiluted SPNS was not a significant eye irritant in rabbits, undiluted SNS was a moderate eye irritant in rabbits. At 2%, SNS was a minimal eye irritant in rabbits. Undiluted SNS was at most a mild irritant in Guinea pigs, and was nonirritating at 20% and 2%. In a delayed contact hypersensitivity test in Guinea pigs, 30% SNS used in the induction phase and in the challenge phase produced no reactions. In a Guinea pig maximization test, 1% SNS used with Freund's complete adjuvant (FCA) injected in the initial sensitization, 50% SNS applied topically in the second sensitization, and up to 30% SNS applied topically in the challenge phase did not produce any irritation or sensitization. Both ingredients were negative in Ames mutagenesis assays. In clinical studies, SNS was neither an irritant (tested up to 2%), cumulative irritant (tested up to 1%), nor a sensitizer (tested up to 1%). The Panel considered the low penetration in concert with the low concentrations of use of these ingredients and the absence of significant overall toxicity and the limited negative genotoxicity findings sufficient to support a conclusion that SNS and SPNS are safe as used in cosmetic formulations intended to be applied to the skin. Use of SPNS in a lipstick formulation, was not considered to be different from application to the skin in that the barrier properties of the skin do not apply when these ingredients may contact mucous membranes or may be ingested. Accordingly, the Panel concluded that the available data are insufficient to support the safety of SNS and SPNS in cosmetic formulations that may contact mucous membranes or be ingested. The additional data needed to make a safety assessment for these uses include dermal reproductive and developmental toxicity data and one genotoxicity assay in a mammalian system, and if that study is positive, then a 2-year dermal carcinogenicity study using National Toxicology Program (NTP) methods may be needed.

Ozonation of an azo dye C.I. Remazol Black 5 and toxicological assessment of its oxidation products.

The effect of ozonation (20.5 mgl(-1)) on the degradation processes of an azo dye, Remazol Black 5 (RB5; CI) was studied. Conventional parameters such as chemical oxygen demand (COD), total organic carbon (TOC), pH, conductivity, colour removal, biodegradability (BOD(5/28)), and toxic potential of the dye and its degradation products were monitored during the process. The results obtained indicated that ozonation is a highly effective way to remove the colour of a corresponding dye solution. However, a considerable organic load still remained as indicated by high COD and TOC residues. The COD, TOC reductions were about 40% and 25% for 6 h ozonation of 2 gl(-1) RB5 aqueous solution. During the ozonation process the rapid decrease of pH and the sharp increase of conductivity indicated the formation of acidic by-products and small fragments and ions which were identified by high performance ion chromatography. The BOD28 data revealed that first by-products after partial ozonation (10-150 min) of RB5 were more biodegradable than the parent compound and ozonation can enhance the biodegradability of azo dyes. During the first 150 min of total 360 min of oxidation, the formation of first by-products with high toxic potential took place as it could be confirmed by two acute toxicity-screening tests, the bioluminescence test (Vibrio fischerii) and the neutral red cytotoxicity assay (rat hepatoma cells). The significant enhancement of microbial biodegradability after long-term ozonation could also be seen as a decrease of toxic intermediates in correlation with the ozonation time as indicated in BOD28 biological degradation test results.

Genotoxicity studies on the azo dye Direct Red 2 using the in vivo mouse bone marrow micronucleus test.

The clastogenicity of the azo dye Direct Red 2 (DR2) has been investigated using the murine bone marrow micronucleus assay. A potent dose-dependent response was observed following oral gavage of DR2 up to 4 mg/kg, after which significant toxicity to the erythroid compartment was observed. The route of administration had a significant effect on the frequency of micronucleus formation: intraperitoneal injection was approximately two-fold less clastogenic than the equivalent dose delivered orally (p<0.05). The requirement for activation of DR2 by intestinal microflora was indicated by the fact that mice given acid-treated water prior to administration of DR2 showed a significant reduction (40%; p<0.001) in micronucleated polychromatic erythrocyte formation. The implications of these findings for the health and safety of occupationally exposed workers are discussed.

Water-soluble metal naphthalocyanines--near-IR photosensitizers: cellular uptake, toxicity and photosensitizing properties in NHIK 3025 human cancer cells.

Metal naphthalocyanine complexes (MNCSs) absorb light in the near-IR spectral region (760 nm) where tissue penetration is optimal and they have been proposed as agents for photodynamic therapy (PDT). Sulphonated derivatives of tris-(2,3-naphthalocyanato) bis-chloroaluminium(III) and zinc(II) with various degrees of sulphonation were prepared. Cellular uptake, aggregation in cellular environments, cytotoxicity and photosensitizing properties were studied. Three of the four dyes studied were taken up by cells to a satisfactory degree and were not cytotoxic at the concentration used (10 micrograms ml-1). The least sulphonated sample of zinc naphthalocyanine produced some phototoxic effects (LD50 = 1.12 J cm-2). All the other samples of sulphonated naphthalocyanine were found to be aggregated inside the NHIK 3025 cells, preventing any significant PDT effect.

Long-term toxicity study of carmoisine in rats using animals exposed in utero.

Groups of 114 (control) or 66 (treated) rats of each sex were fed diets providing 0 (control), 100, 400 or 1200 mg carmoisine/kg body weight/day for 9 wk. Within each group the animals were mated monogamously. Treatment continued uninterrupted until the young were randomly selected (where possible one/sex/litter) from each of the litters to provide groups of 90 (control) and 54 (treated) rats of each sex. These received the same treatment as their parents for up to 110 wk for females or 115 wk for males. Apart from coloration of the fur, urine and faeces, treated rats did not differ in appearance or behaviour from the controls. Mortality was not affected by treatment. High-dose groups had reduced body-weight gain compared with that of the controls, despite slightly higher food intakes. Increased water intakes in the same animals accompanied a tendency to excrete larger volumes of urine. Haematological investigations at months 3, 6, 9, 12, 18 and 24, and on all survivors at the end of the study showed no treatment-related effects. Urine studies on 20 rats/sex/group at months 3, 6, 12, 18 and 24 showed no consistent treatment-related changes. Analyses of serum collected at the end of the study demonstrated low glucose concentrations in both sexes of the high-dose group and in intermediate-dose females. A few high-dose males had bladder hyperplasia while some high-dose females had increased incidences of adrenal blood/fibrin cysts or internal hyperplasia/medial hypertrophy of the pancreatic blood vessels. Tumours occurred with a similar distribution and incidence in all groups apart from an increased incidence of adrenal phaeochromocytoma in high-dose males. The incidence seen was well within the background incidence for this relatively common tumour in the same strain of rat under similar conditions. It is concluded that carmoisine is not carcinogenic and that the no-untoward-effect level in this study was 400 mg carmoisine/kg body weight/day.

An association of upper respiratory cancer with exposure to diethyl sulfate.

A morbidity and mortality study of workers at an alcohol manufacturing plant which included several weak acid isopropyl alcohol units and a strong acid ethanol unit is described. An excess mortality of upper respiratory cancer was found and associated with work on the strong acid ethanol unit. The strong acid ethanol process used resulted in high concentrations of diethyl sulfate, which has been shown to be carcinogenic in animals, and the unit, which closed on 1975, had significant opportunities for worker exposure to diethyl sulfate. These facts, plus previous reports of excess upper respiratory cancer on strong acid isopropyl alcohol units with similarly high concentrations of the animal carcinogen diisopropyl sulfate, lead to the tentative conclusion that diethyl sulfate was primarily responsible for the ethanol unit cancer cases. In the modern weak acid isopropyl alcohol plants, where only trace amounts of diisopropyl sulfate are present and exposures are much lower, the problems found on the old strong acid units do not exist.

Long-term toxicity studies on Chocolate Brown HT in rats.

Groups of 48 males and 48 female rats were given diets containing 0 (control), 500, 2000 or 10,000 ppm Chocolate Brown HT for 2 years. These treatments had no adverse effect on mortality, body-weight gain, food or water consumption, haematology, renal function, serum constituents, organ weight or histopathology. From the incidence of tumours observed in the control and test animals it is concluded that Chocolate Brown HT did not exert any carcinogenic effect and that the no-untoward-effect level was 10,000 ppm.