Yellow-colored extract from cashew byproduct - Nonclinical safety assessment.

Natural and synthetic dyes are widely used in foodstuff, medicines and cosmetics industries to enhance and/or restore the color of the final products. This study aimed to evaluate the safety of oral consumption of one carotenoids and anacardic acids-enriched extract (CAE), obtained by green extraction from cashew apple residue fibers, a byproduct of the cashew juice industry. Presenting intense yellow color, CAE could be proposed as a new natural dye. Single and repeated-dose oral toxicity (30 days) were evaluated in female Swiss mice at doses ranging from 50 to 1000 mg/kg, while (anti)mutagenic effects were evaluated in CHO-K1 cells (in vitro Cytokinesis-Block Micronucleus assay - CBMN) and in erythrocytes collected from murine bone marrow (in vivo). CAE did not induce toxic or mutagenic effects in female mice even after 30 days of treatment, regardless of the dose used. Considering cyclophosphamide (CPA)-challenged animals treated with CAE, neither antimutagenic effect was observed nor CAE increased CPA-mutagenic effects although in vitro CBMN results indicated that CAE might increase methyl methanesulfonate-induced micronuclei (MN) frequency besides promoting reduction on CPA-induced MN frequency. The obtained results suggest that CAE may be a safe source of carotenoids with potential use as industrial dye.

Asparagus densiflorus in a vertical subsurface flow phytoreactor for treatment of real textile effluent: A lab to land approach for in situ soil remediation.

This study explores the potential of Asparagus densiflorus to treat disperse Rubin GFL (RGFL) dye and a real textile effluent in constructed vertical subsurface flow (VSbF) phytoreactor; its field cultivation for soil remediation offers a real green and economic way of environmental management. A. densiflorus decolorized RGFL (40 gm L-1) up to 91% within 48 h. VSbF phytoreactor successfully reduced American dye manufacture institute (ADMI), BOD, COD, Total Dissolved Solids (TDS) and Total Suspended Solids (TSS) of real textile effluent by 65%, 61%, 66%, 48% and 66%, respectively within 6 d. Oxidoreductive enzymes such as laccase (138%), lignin peroxidase (129%), riboflavin reductase (111%) were significantly expressed during RGFL degradation in A. densiflorus roots, while effluent transformation caused noteworthy induction of enzymes like, tyrosinase (205%), laccase (178%), veratryl oxidase (52%). Based on enzyme activities, UV-vis spectroscopy, FTIR and GC-MS results; RGFL was proposed to be transformed to 4-amino-3- methylphenyl (hydroxy) oxoammonium and N, N-diethyl aniline. Anatomical study of the advanced root tissue of A. densiflorus exhibited the progressive dye accumulation and removal during phytoremediation. HepG2 cell line and phytotoxicity study demonstrated reduced toxicity of biotransformed RGFL and treated effluent by A. densiflorus, respectively. On field remediation study revealed a noteworthy removal (67%) from polluted soil within 30 d.

Pectin microgel particles as high adsorption rate material for methylene blue: Performance, equilibrium, kinetic, mechanism and regeneration studies.

The pectin gel has been proved to be an effective material for methylene blue (MB) removal, but it presented low adsorption rate. To get over the vice, the pectin microgel particles (PMP) was prepared. No matter high or low initial MB concentration, the PMP presented high adsorption rate with equilibrium time of 20min. The adsorption process based on monolayer adsorption and adsorbance of 284.09mg/g was obtained. What's more, the adsorption process was electrostatic adsorption with mean free energy of 74.223kJ/mol. The pseudo-second-order kinetic model fitted perfectly to the experimental data. The MB uptake was controlled by film diffusion mechanism. Furthermore, the recovery efficiency of regenerated PMP were higher than 80% after three cycles. The present study showed the PMP presented acceptable adsorbance, high adsorption rate and recovery efficiency. Thus, we believe that the PMP was a promising candidate for MB cleanup.

Biodegradation of Azure-B dye by Serratia liquefaciens and its validation by phytotoxicity, genotoxicity and cytotoxicity studies.

The azo dyes in textile industry are a major source of environmental pollution and cause serious threat to aquatic flora and fauna. The present study aims to evaluate the potential of previously isolated lignin peroxidase (LiP) enzyme producing Serratia liquefaciens in degradation of Azure-B (AB) dye. S. liquefaciens showed rapid decolourisation of AB dye (100 mg L-1) in mineral salt medium (MSM) supplemented with 0.2% glucose and yeast extract, and more than 90% dye decolourisation was observed at 48 h when incubated at 30 °C. Decolourisation conditions were optimized by Response Surface Methodology (RSM) using Box-Behnken Designs (BBD). The dye degradation was further confirmed by ATR-FTIR and GC-MS analysis. Toxicological studies of untreated (UT) and bacterial treated (BT) AB dye solutions were studied by using phytotoxicity, genotoxicity and cytotoxicity endpoints. Phytotoxicity assay using Vigna radiata indicated that bacterial treatment led to detoxification of AB dye. Genotoxicity assay with Allium cepa showed that pure AB dye solutions significantly reduced mitotic index (MI) and induced various chromosomal abnormalities (CAs) like c-mitosis, stickiness, chromosome break, anaphase bridges, vagrant chromosomes and binucleated and micronucleated cell in the root tip cells, whereas, bacterial treated solutions induced relatively less genotoxicity in nature. Improved cell survivability (%) was also noted in kidney cell line (NRK-52E) after S. liquefaciens treated dye solutions than the pure dye solutions. The findings suggest that S. liquefaciens could be a potential bacterium for azo dye degradation, as it is effective in lowering of toxic effects of AB dye.

Degradation of textile dyes by cyanobacteria

Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.

Safety and regulatory review of dyes commonly used as excipients in pharmaceutical and nutraceutical applications.

Color selection is one of the key elements of building a strong brand development and product identity in the pharmaceutical industry, besides to prevent counterfeiting. Moreover, colored pharmaceutical dosage forms may increase patient compliance and therapy enhancement. Although most synthetic dyes are classified as safe, their regulations are stricter than other classes of excipients. Safety concerns have increased during the last years but the efforts to change to natural dyes seem to be not promising. Their instability problems and the development of "non-toxic" dyes is still a challenge. This review focuses specifically on the issues related to dye selection and summarizes the current regulatory status. A deep awareness of toxicological data based on the public domain, making sure the compliance of standards for regulation and safety for successful product development is provided. In addition, synthetic strategies are provided to covalently bind dyes on polymers to possibly overcome toxicity issues.

Comparative short-term inhalation toxicity of five organic diketopyrrolopyrrole pigments and two inorganic iron-oxide-based pigments.

Diketopyrrolopyrroles (DPP) are a relatively new class of organic high-performance pigments. The present inhalation and particle characterization studies were performed to compare the effects of five DPP-based pigments (coarse and fine Pigment Red 254, coarse and fine meta-chloro DPP isomer and one form of mixed chlorinated DPP isomers) and compare it to coarse and fine inorganic Pigment Red 101. Wistar rats were exposed head-nose to atmospheres of the respective materials for 6 h/day on 5 consecutive days. Target concentrations were 30 mg/m(3) as high dose for all compounds and selected based occupational exposure limits for respirable nuisance dust. Toxicity was determined after end of exposure and after 3-week recovery using broncho-alveolar lavage fluid (BALF) and microscopic examinations of the entire respiratory tract. Mixed chlorinated DPP isomers and coarse meta-chloro DPP isomer caused marginal changes in BALF, consisting of slight increases of polymorphonuclear neutrophils, and in case of coarse meta-chloro DPP increased MCP-1 and osteopontin levels. Mixed chlorinated DPP isomers, Pigment Red 254, and meta-chloro DPP caused pigment deposits and phagocytosis by alveolar macrophages, slight hypertrophy/hyperplasia of the bronchioles and alveolar ducts, but without evidence of inflammation. In contrast, only pigment deposition and pigment phagocytosis were observed after exposure to Pigment Red 101. All pigments were tolerated well and caused only marginal effects in BALF or no effects at all. Only minor effects were seen on the lung by microscopic examination. There was no evidence of systemic inflammation based on acute-phase protein levels in blood.

Synthesis of porous starch xerogels modified with mercaptosuccinic acid to remove hazardous gardenia yellow.

Mercaptosuccinic acid (MSA) molecules were inserted into potato starch, leading to the breaking of intrinsic H-bonds within macromolecular chains of starch and the formation of intermolecular H-bonds between MSA and starch, which could be verified by Fourier transform infrared spectroscopy (FT-TR). MSA modified porous starch xerogels (PSX/MSA) were obtained after freeze-drying the MSA modified starch, and they were characterized by field emission scanning electron microscopy (FESEM), exhibiting the intriguing porous structure due to the separation of starch chains by MSA molecules. The PSX/MSA were then used as the adsorbents to remove gardenia yellow (GY), a natural colorant with genotoxicity. Due to the porous structure of PSX and the introduced carboxyl groups from MSA, the adsorption capacity of the PSX/MSA was much higher than that of the starch xerogels alone (SX). The adsorption behaviors of GY by the PSX/MSA fitted both the Freundlich isotherm model and the pseudo-second-order kinetic model, and the efficient adsorption of GY suggested that the PSX/MSA might be potential adsorbents for the removal of dyes from contaminated aquatic systems.

Dermal Toxicity of Flake-Like α-Alumina Pigments.

Aluminum is one of the most widely used nonferrous metals and an important industrial material, especially for automotive coatings. However, potential toxicity caused by aluminum in humans limits the used of this metal. α-alumina is the most stable form of aluminum in various phases. Although the results of studies evaluating the dermal toxicity of α-alumina remained unclear, this compound can still be used as a pigment in cosmetics for humans. In the current study, we further evaluated the dermal cytotoxic effects of α-alumina on human skin cells and an in vivo mouse model. We also measured the in vitro penetration profile of flake-like α-alumina in porcine skin and assessed the degree of cellular metabolic disorders. Our findings demonstrated that treatment with flake-like α-alumina did not significantly affect cell viability up to 24 h. This compound was found to have a non-penetration profile based on a Franz modified diffusion cell assay. In addition, flake-like α-alumina was not found to induce dermal inflammation as assessed by histology of epidermal architecture, hyperplasia, and the expression of Interleukin-1ß and Cyclooxygenase-2. Results of the cellular metabolic disorder assay indicated that flake-like α-alumina does not exert a direct effect on human skin cells. Taken together, our findings provided not only evidence that flake-like α-alumina may serve as a pearlescent pigment in cosmetics but also experimental basis utilizing α-alumina for human application. Our results also obviously provide new insight of the further toxicity study to aluminum based nanoparticles for skin.

Improved biodegradation of textile dye effluent by coculture.

The present study demonstrates the de-colorization and degradation of textile effluent by coculture consisting of three bacterial species isolated from textile effluent contaminated environment with an aim to reduce the treatment time. The isolates were identified as Ochrobactrum sp., Pseudomonas aeruginosa and Providencia vermicola by 16S rRNA analysis. Their secondary structure was predicted and GC content of the sequence was found to be 54.39, 52.10, and 52.53%. The co-culture showed a prominent increase in the degradation activity due to the action of oxidoreductase enzymatic mechanism of laccase, NADH-DCIP reductase and azoreductase activity. The biodegradability index of 0.75 was achieved with 95% chemical oxygen demand (COD) reduction in 16 h and 78 and 85% reduction in total organic carbon (TOC) and total solids was observed. Bioaccumulation of metals was identified by X-ray diffraction (XRD) analysis. The effective decolorization was confirmed from the results of UV-vis spectroscopy, high performance liquid chromatography and Fourier transformed infrared spectrometer analyzes. The possible degradation pathway was obtained from the analysis of liquid chromatography-mass spectroscopy analysis and the metabolites such as 2-amino naphthalene and N-phenyl-1.3,5 triazine were observed. The toxic nature of the effluent was analyzed using phyto-toxicity, cell-death assay and geno-toxicity tests.

Evaluation of in vitro efficacy for decolorization and degradation of commercial azo dye RB-B by Morganella sp. HK-1 isolated from dye contaminated industrial landfill.

Reactive Black-B (RB-B) - one of the multi-sulphonated reactive azo dye - is being used extensively in textile as well as paper industries. Reactive azo dyes comprise of a significant group of synthetic compounds categorized as xenobiotics and its abatement from the environment still remains a challenge. In the present study, a newly isolated indigenous bacterial strain Morganella sp. HK-1 was exploited for its ability to decolorize and degrade RB-B dye. The isolate completely degraded RB-B (20 g L(-1)) within 24h under static conditions. Furthermore, the visible and FTIR spectral analysis established the bio-degradation of RB-B. The degraded metabolites of RB-B by Morganella sp. HK-1 were identified by GC-MS analysis as disodium 3,4,6-triamino-5-hydroxynaphthalene-2,7-disulfonate, 4-aminophenylsulfonylethyl hydrogen sulfate, naphthalene-1-ol, aniline and benzene. Based on this information, a putative pathway of degradation of RB-B by Morganella sp. HK-1 has been proposed. This study is the first report on elucidation of mechanism of bacterial degradation of RB-B dye. Furthermore, phytotoxicity, genotoxicity and aquatic acute toxicity studies of the parent dye and the bio-degraded dye products revealed drastic reduction in the toxicity of metabolites as compared to the parent dye. This implies that the biotreatment of the dye is of non-toxic nature. This study thus indicates the effectiveness of Morganella sp. HK-1 for the treatment of textile effluents containing sulphonated azo dyes.

A comprehensive evaluation of the toxicology of monogram inks added to experimental cigarettes.

CONTEXT: Cigarettes often have a small identifying mark (monogram) printed either on the cigarette paper toward the filter end of the cigarette or on the tipping paper. OBJECTIVE: A battery of tests was used to compare the toxicology of mainstream smoke from experimental cigarettes manufactured with different monogram inks. Cigarettes with different concentrations of different pigments were compared with cigarettes without ink, and with a control ink. MATERIALS AND METHODS: Smoke from each of the experimental cigarettes was evaluated using analytical chemistry and in vitro bacterial mutagenicity (Salmonella, five strains, ± S9) and cytotoxicity (neutral red uptake) assays. RESULTS: No differences were observed between experimental cigarettes printed with three different pigment loads of iron oxide-based Black pigment and non-printed cigarettes. In general, no dose response was observed. However, increases in certain smoke constituents were found to correlate with Pigment Yellow 14 (also known as benzidine yellow) and Pigment Blue 15 (copper phthalocyanine). Increases in bacterial mutagenicity were observed for high-level print of Pigment Yellow 14 in TA98 and TA1537 and the high-level print of Pigment Blue 15 in TA98. In vitro cytotoxicity of mainstream smoke was unaffected by the presence of monogram ink on cigarettes. CONCLUSION: Statistically significant dose-responsive constituent changes and an increase in mutagenicity were observed with inclusion of Pigment Yellow 14 and Pigment Blue 15. Other pigments showed minimal toxicological activity.

Cytotoxic effects of Reactive Blue 33 on Allium cepa determined using Taguchi's L8 orthogonal array.

In this study, Taguchi L8 experimental design was applied to determine cytotoxic effects of Reactive Blue 33, which is the most toxic azo reactive dye species, on Allium cepa. With this aim, A. cepa test system was performed to achieve targeted experimental design with three factors (concentration of dye, pH and volume) in two different levels. Toxic conditions were determined considering calculated signal-to-noise ratios. "Smaller is better" approach was followed to calculate signal-to-noise ratios as it was aimed to obtain lower root lengths. In the work, toxic effects of azo dye were also predicted by using the Taguchi method. Taguchi model showed that experimental and predicted values were closer to each other demonstrating the success of Taguchi approach.

Manganese peroxidase h4 isozyme mediated degradation and detoxification of triarylmethane dye malachite green: optimization of decolorization by response surface methodology.

A cDNA encoding for manganese peroxidase isozyme H4 (MnPH4), isolated from Phanerochaete chrysosporium, was expressed in Pichia pastoris, under the control of alcohol oxidase I promoter. The recombinant MnPH4 was efficiently secreted onto media supplemented with hemin at a maximum concentration of 500 U/L, after which purified rMnPH4 was used to decolorize the triarylmethane dye malachite green (MG). Response surface methodology (RSM) was employed to optimize three different operational parameters for the decolorization of MG. RSM showed that the optimized variables of enzyme (0.662 U), MnSO4 (448 µM), and hydrogen peroxide (159 µM) decolorized 100 mg/L of MG completely at 3 h. Additionally, UV-VIS spectra, high-performance liquid chromatography, gas chromatography-mass spectrometry, and liquid chromatography-electrospray ionization/mass spectrometry analysis confirmed the degradation of MG by the formation of main metabolites 4-dimethylamino-benzophenone hydrate, N, N-dimethylaniline (N,N-dimethyl-benzenamine), and methylbenzaldehyde. Interestingly, it was found that rMnPH4 mediates hydroxyl radical attack on the central carbon of MG. Finally, rMnPH4 degraded MG resulted in the complete removal of its toxicity, which was checked under in vitro conditions.

Batch and continuous biodegradation of Amaranth in plain distilled water by P. aeruginosa BCH and toxicological scrutiny using oxidative stress studies.

Bacterium Pseudomonas aeruginosa BCH was able to degrade naphthylaminesulfonic azo dye Amaranth in plain distilled water within 6 h at 50 mg l(-1) dye concentration. Studies were carried out to find the optimum physical conditions and which came out to be pH 7 and temperature 30 °C. Amaranth could also be decolorized at concentration 500 mg l(-1). Presence of Zn and Hg ions could strongly slow down the decolorization process, whereas decolorization progressed rapidly in presence of Mn. Decolorization rate was increased with increasing cell mass. Induction in intracellular and extracellular activities of tyrosinase and NADH-DCIP reductase along with intracellular laccase and veratryl alcohol oxidase indicated their co-ordinate action during dye biodegradation. Up-flow bioreactor studies with alginate immobilized cells proved the capability of strain to degrade Amaranth in continuous process at 20 ml h(-1) flow rate. Various analytical studies viz.--HPLC, HPTLC, and FTIR gave the confirmation that decolorization was due to biodegradation. From GC-MS analysis, various metabolites were detected, and possible degradation pathway was predicted. Toxicity studies carried out with Allium cepa L. through the assessment of various antioxidant enzymes viz. sulphur oxide dismutase, guaiacol peroxidase, and catalase along with estimation of lipid peroxidation and protein oxidation levels conclusively demonstrated that oxidative stress was generated by Amaranth.

Biodecolorization of azo dye Remazol orange by Pseudomonas aeruginosa BCH and toxicity (oxidative stress) reduction in Allium cepa root cells.

In this report a textile azo dye Remazol orange was degraded and detoxified by bacterium Pseudomonas aeruginosa BCH in plain distilled water. This bacterial decolorization performance was found to be pH and temperature dependent with maximum decolorization observed at pH 8 and temperature 30 °C. Bacterium tolerated higher dye concentrations up to 400 mg l(-1). Effect of initial cell mass showed that higher cell mass concentration can accelerate decolorization process with maximum of 92 % decolorization observed at 2.5 g l(-1) cell mass within 6.5 h. Effect of various metal ions showed Mn has inducing effect whereas Zn strongly inhibited the decolorization process at 5 mM concentration. Analysis of biodegradation products carried out with UV-vis spectroscopy, HPTLC and FTIR confirmed the decolorization and degradation of Remazol orange. Possible route for the degradation of dye was proposed based on GC-MS analysis. During toxicological scrutiny in Allium cepa root cells, induction in the activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX) and inhibition of catalase (CAT) along with raised levels of lipid peroxidation and protein oxidation in dye treated samples were detected which conclusively indicated the generation of oxidative stress. Less toxic nature of the dye degraded products was observed after bacterial treatment.

Ecofriendly degradation, decolorization and detoxification of textile effluent by a developed bacterial consortium.

Present study illustrates the effectual decolorization and degradation of the textile effluent using a developed bacterial consortium SDS, consisted of bacterial species Providencia sp. SDS and Pseudomonas aeuroginosa strain BCH, originally isolated from dye contaminated soil. The intensive metabolic activity of the consortium SDS led to complete decolorization of textile effluent within 20 h at pH 7 and temperature 30°C. Significant induction in the activities of veratryl alcohol oxidase, laccase, azoreductase and DCIP reductase were observed during decolorization, which indicates their involvement in decolorization and degradation process. The decolorization and biodegradation was monitored using UV-vis spectroscopy, IR spectroscopy, HPLC and HPTLC analysis. Toxicological analysis of effluent before and after treatment was performed using classical Allium cepa test. Investigations of various toxicological parameters viz, oxidative stress response, cytotoxicity, genotoxicity and phytotoxicity, collectively concludes that, the toxicity of effluent reduces significantly after treatment with consortium SDS.

Combined effects of sugarcane bagasse extract and synthetic dyes on the growth and bioaccumulation properties of Pichia fermentans MTCC 189.

Bioaccumulation of synthetic dyes viz. Acid Blue 93, Direct Red 28 and Basic Violet 3 by growing cells of yeast, Pichia fermentans MTCC 189 was investigated in growth media prepared from sugarcane bagasse extract. The maximum dye bioaccumulation was determined at pH 5.0 for all the dyes tested. Two kinetic models viz. Noncompetitive and Uncompetitive models were tested in order to determine the toxic effects of dyes on the specific growth rate of P. fermentans MTCC 189. Basic Violet 3 was found to be more toxic than the other two dyes. The combined effects of sugarcane bagasse extract and initial Basic Violet 3 dye concentrations on the specific growth rate and dye bioaccumulation efficiency of P. fermentans MTCC 189 was investigated and optimized using Response Surface Methodology (RSM). A 2(2) full factorial central composite design was successfully used for analysis of results. The optimum combination predicted via RSM confirmed that P. fermentans MTCC 189 was capable of bioaccumulating Basic Violet 3 dye upto 69.8% in the medium containing 10 mg/L of dye and 24 g/L sugar extracted from sugarcane bagasse.