scholarly journals Bacterial decolourization of azo dyes

2017 ◽  
Vol 16 (4) ◽  
pp. 1-12
Author(s):  
Amrita Nair ◽  
Nandini Rajendhiran ◽  
R Varsha ◽  
Biljo V Joseph ◽  
V L Vasantha
Keyword(s):  
Azo Dyes ◽  
Organic Contaminants ◽  
Control Strategies ◽  
Textile Effluent ◽  
Health Concern ◽  
Synthetic Dyes ◽  
Chemical Methods ◽  
Physico Chemical ◽  
Pure Cultures ◽  
Dyes And Pigments

Release of textile effluent into the environment is a matter of health concern. Dyes and pigments that are part of textile effluent generate hazardous wastes which are generally inorganic or organic contaminants. Among the present pollution control strategies, biodegradation of synthetic dyes by microbes is evolving as a promising approach, even more than physico-chemical methods. While both mixed cultures and pure cultures have been used to achieve efficient biodegradation, no conclusive result has been determined. This paper aims at checking the efficiency of mixed culture of sewage and pure isolates in degradation of azo dyes, both simple dyes like methyl red and methyl orange and a more complex dye like Janus green.

scholarly journals Bio-removal of Azo Dyes: A Review

2017 ◽  
Vol 5 (2) ◽  
pp. 108-126 ◽  
Author(s):  
Pradeep Kumar Singh ◽  
Ram Lakhan Singh
Keyword(s):  
Azo Dyes ◽  
Textile Industry ◽  
Textile Wastewater ◽  
Oxidative Enzymes ◽  
Synthetic Dyes ◽  
Biological Processes ◽  
Chemical Methods ◽  
Physico Chemical ◽  
Pharmaceutical Industries ◽  
Low Efficiency

Synthetic dyes are widely used in textile, paper, food, cosmetics and pharmaceutical industries with the textile industry as the largest consumer. Among all the available synthetic dyes, azo dyes are the largest group of dyes used in textile industry. Textile dyeing and finishing processes generate a large amount of dye containing wastewater which is one of the main sources of water pollution problems worldwide. Several physico-chemical methods have been applied to the treatment of textile wastewater but these methods have many limitations due to high cost, low efficiency and secondary pollution problems. As an alternative to physico-chemical methods, biological methods comprise bacteria, fungi, yeast, algae and plants and their enzymes which received increasing interest due to their cost effectiveness and eco-friendly nature. Decolorization of azo dyes by biological processes may take place either by biosorption or biodegradation. A variety of reductive and oxidative enzymes may also be involved in the degradation of dyes. This review provides an overview of decolorization and degradation of azo dyes by biological processes and establishes the fact that these microbial and plant cells are significantly effective biological weapon against the toxic azo dyes. Int. J. Appl. Sci. Biotechnol. Vol 5(2): 108-126

scholarly journals Study of Modern Nano Enhanced Techniques for Removal of Dyes and Metals

2014 ◽  
Vol 2014 ◽  
pp. 1-20 ◽  
Author(s):  
Samavia Batool ◽  
Shatirah Akib ◽  
Mushtaq Ahmad ◽  
Khaled S. Balkhair ◽  
Muhammad Aqeel Ashraf
Keyword(s):  
Azo Dyes ◽  
Organic Contaminants ◽  
Industrial Effluent ◽  
Engineered Nanoparticles ◽  
Synthetic Dyes ◽  
Simultaneous Removal ◽  
Treatment Techniques ◽  
Terrestrial Life ◽  
Treatment Technologies ◽  
Microbial Strains

Industrial effluent often contains the significant amount of hexavalent chromium and synthetic dyes. The discharge of wastewater without proper treatment into water streams consequently enters the soil and disturbs the aquatic and terrestrial life. A range of wastewater treatment technologies have been proposed which can efficiently reduce both Cr(VI) and azo dyes simultaneously to less toxic form such as biodegradation, biosorption, adsorption, bioaccumulation, and nanotechnology. Rate of simultaneous reduction of Cr(VI) and azo dyes can be enhanced by combining different treatment techniques. Utilization of synergistic treatment is receiving much attention due to its enhanced efficiency to remove Cr(VI) and azo dye simultaneously. This review evaluates the removal methods for simultaneous removal of Cr(VI) and azo dyes by nanomicrobiology, surface engineered nanoparticles, and nanophotocatalyst. Sorption mechanism of biochar for heavy metals and organic contaminants is also discussed. Potential microbial strains capable of simultaneous removal of Cr(VI) and azo dyes have been summarized in some details as well.

Photocatalytic degradation of synthetic dye under sunlight

2007 ◽  
Vol 61 (1) ◽  
pp. 7-12 ◽  
Author(s):  
Dusan Mijin ◽  
Mirko Jugurdzija ◽  
Petar Jovancic
Keyword(s):  
Textile Industry ◽  
Heterogeneous Photocatalysis ◽  
Textile Dye ◽  
Synthetic Dyes ◽  
Chemical Methods ◽  
Dye Pollutants ◽  
Photodegradation Efficiency ◽  
Photodegradation Rate ◽  
Physico Chemical ◽  
Ph Increase

Synthetic dyes are widely used in the textile industry. Dye pollutants from the textile industry are an important source of environmental contamination. The majority of these dyes are toxic, mostly non-biodegradable and also resistant to decomposition by physico-chemical methods. Among new oxidation methods or "advanced oxidation processes", heterogeneous photocatalysis appears as an emerging destructive technology leading to the total mineralization of many organic pollutants. CI Basic Yellow 28 (BY28), commonly used as a textile dye, could be photocatalytically degraded using TiU2 as catalyst under sunlight. The effect of some parameters such as the initial catalyst concentration, initial dye concentration, initial NaCl and Na2CO3 concentrations, pH, H2O2 and type of catalyst on the degradation rate of BY28 was examined in details. The presence of NaCl and Na2CO3 led to inhibition of the photodegradation process. The highest photodegradation rate was observed at high pH, while the rate was the lowest at low pH. Increase of the initial H2O2 concentration increased the initial BY28 photodegradation efficiency. ZnO was a better catalyst than TiO2 at low dye concentrations.

Use of a sequencing batch biofilter for degradation of azo dyes (acids and bases)

2000 ◽  
Vol 42 (5-6) ◽  
pp. 329-336 ◽  
Author(s):  
M. Quezada ◽  
I. Linares ◽  
G. Buitrón
Keyword(s):  
Azo Dyes ◽  
Azo Dye ◽  
Degradation Rate ◽  
Removal Rate ◽  
Textile Effluent ◽  
Colour Removal ◽  
Substrate Degradation ◽  
Acids And Bases ◽  
Removal Efficiencies ◽  
Basic Red 46

The degradation of azo dyes in an aerobic biofilter operated in an SBR system was studied. The azo dyes studied were Acid Red 151 and a textile effluent containing basic dyes (Basic Blue 41, Basic Red 46 and 16 and Basic Yellow 28 and 19). In the case of Acid Red 151 a maximal substrate degradation rate of 288 mg AR 151/lliquid·d was obtained and degradation efficiencies were between 60 and 99%. Mineralization studies showed that 73% (as carbon) of the initial azo dye was transformed to CO2 by the consortia. The textile effluent was efficiently biodegraded by the reactor. A maximal removal rate of 2.3 kg COD/lliquid·d was obtained with removal efficiencies (as COD) varying from 76 to 97%. In all the cycles the system presented 80% of colour removal.

scholarly journals Risk factors associated with Ctenocephalides felis flea infestation of peri-urban goats: a neglected parasite in an under-appreciated host

2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Julia Rose Dahm ◽  
Jordana Burdon Bailey ◽  
Robert F. Kelly ◽  
Patrick Chikungwa ◽  
Julius Chulu ◽  
...  
Keyword(s):  
Risk Factors ◽  
Urban Communities ◽  
Control Strategies ◽  
Animal Health ◽  
Animal Husbandry ◽  
Ctenocephalides Felis ◽  
Disease Spread ◽  
Health Concern ◽  
Cross Sectional ◽  
Flea Infestation

AbstractGoats are critical in mixed smallholder agricultural systems in lower and middle-income countries, while fleas are important human and animal health concerns around the world. Convenience sampling was used to describe and consider risk factors for flea infestations of peri-urban goats, with the aim of informing the iterative development of animal husbandry and management based control strategies. Seven hundred and ninety-two goats were examined in 228 households across 10 peri-urban communities surrounding Blantyre in southern Malawi. The prevalence of Ctenocephalides felis fleas was 18.3, 37.1 and 100% at the levels of individual goats, households and communities, respectively, highlighting a neglected human and animal health concern. Constant introduction of new livestock coupled to a lack of biosecurity within communities, the ubiquitous presence of dog and cat hosts for C. felis, the frequency and thoroughness of cleaning overnight goat accommodation, and goat age less than 12 months old were identified as risk factors for flea infestation. This focal cross-sectional study highlights the significance of fleas in peri-urban communities and uncovers trends and commonalities that are needed to inform sustainable disease management. The majority of the peri-urban goat keepers were female, had resided in the same community throughout their whole life and had primary level education. Advice on the planned management of fleas in livestock needs to be tailored towards this demographic group. This approach affords an opportunity to promote public health measures to address household flea infestations and zoonotic disease spread.

scholarly journals Contribution of Nanomaterials to the Development of Electrochemical Aptasensors for the Detection of Antimicrobial Residues in Food Products

Chemosensors ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 69
Author(s):  
Valérie Gaudin
Keyword(s):  
Signal Amplification ◽  
Electrochemical Sensors ◽  
Low Cost ◽  
Food Products ◽  
Animal Origin ◽  
Screening Methods ◽  
Chemical Methods ◽  
Portable Instrumentation ◽  
Physico Chemical ◽  
Antimicrobial Residues

The detection of antimicrobial residues in food products of animal origin is of utmost importance. Indeed antimicrobial residues could be present in animal derived food products because of animal treatments for curative purposes or from illegal use. The usual screening methods to detect antimicrobial residues in food are microbiological, immunological or physico-chemical methods. The development of biosensors to propose sensitive, cheap and quick alternatives to classical methods is constantly increasing. Aptasensors are one of the major trends proposed in the literature, in parallel with the development of immunosensors based on antibodies. The characteristics of electrochemical sensors (i.e., low cost, miniaturization, and portable instrumentation) make them very good candidates to develop screening methods for antimicrobial residues in food products. This review will focus on the recent advances in the development of electrochemical aptasensors for the detection of antimicrobial residues in food products. The contribution of nanomaterials to improve the performance characteristics of electrochemical aptasensors (e.g., Sensitivity, easiness, stability) in the last ten years, as well as signal amplification techniques will be highlighted.

scholarly journals Water quality and antifungal susceptibility of opportunistic yeast pathogens from rivers

2016 ◽  
Vol 75 (6) ◽  
pp. 1319-1331 ◽  
Author(s):  
M. E. Monapathi ◽  
C. C. Bezuidenhout ◽  
O. H. J. Rhode
Keyword(s):  
Water Quality ◽  
Antifungal Susceptibility ◽  
Principal Component ◽  
Water Sources ◽  
Health Concern ◽  
Rrna Gene ◽  
Biochemical Tests ◽  
Livestock Farming ◽  
Physico Chemical ◽  
26S Rrna

Yeasts from water sources have been associated with diseases ranging from superficial mucosal infections to life threatening diseases. The aim of this study was to determine the water quality as well as diversity and antifungal susceptibility of yeasts from two rivers. Yeast levels and physico-chemical parameter data were analyzed by principal component analysis to determine correlations between physico-chemical data and yeast levels. Yeast morphotypes were identified by biochemical tests and 26S rRNA gene sequencing. Disk diffusion antifungal susceptibility tests were conducted. Physico-chemical parameters of the water were within target water quality range (TWQR) for livestock farming. For irrigational use, total dissolved solids and nitrates were not within the TWQR. Yeast levels ranged between 27 ± 10 and 2,573 ± 306 cfu/L. Only non-pigmented, ascomycetous yeasts were isolated. Saccharomyces cerevisiae and Candida glabrata were most frequently isolated. Several other opportunistic pathogens were also isolated. A large number of isolates were resistant to azoles, especially fluconazole, but also to other antifungal classes. Candida species were resistant to almost all the antifungal classes. These water sources are used for recreation and religious as well as for watering livestock and irrigation. Of particular concern is the direct contact of individuals with opportunistic yeast, especially the immune-compromised. Resistance of these yeast species to antifungal agents is a further health concern.

scholarly journals The principle of formaldehyde, alcohol, and acetone titrations. With a discussion of the proof and implication of the zwitterion conception

1934 ◽  
Vol 115 (792) ◽  
pp. 121-141 ◽  
Keyword(s):  
Amino Acids ◽  
Carboxyl Groups ◽  
Recent Discussion ◽  
Amino Groups ◽  
Chemical Methods ◽  
Titration Method ◽  
Physico Chemical ◽  
Empirical Argument ◽  
Chemical Evidence

Consideration of the implications of the zwitterion hypothesis of Bjerrum (1923) makes it desirable to state afresh the principles underlying the methods commonly employed in the titration of amino-acids. Deductions of considerable theoretical importance, cf., e. g ., Calvery (1933) are still being made on the supposition that the alkalimetric formaldehyde titration method of Sørensen (1907) and the corresponding alcohol method of Foreman (1920) and of Willstätter and Waldschmidt-Leitz (1921) estimate the carboxyl groups of amino-acids whilst the acidimetric acetone titration of Linderstrøm-Lang (1928) estimates the amino-groups. Yet the zwitterion hypothesis indicates that this assumption is the reverse of the truth. Discussion is greatly facilitated by collective consideration of recent physico-chemical evidence clarifying the principles upon which these common bio-chemical methods rest. In a recent discussion of two of the titrimetric methods (Van Slyke and Kirk, 1933) the existence of this evidence is ignored, so that it becomes necessary to systematize and elaborate the empirical argument of these authors in the light of the relevant investigations of Grünhut (1919), Cray and Westrip (1925), Michaelis and Mizutani (1925), Birch and Harris (1930, b ), and Levy (1933). At the same time new and useful developments are indicated.

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