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Hexavalent Chromium Reduction in Tannery Effluent by Bacterial Species Isolated from Tannery Effluent Contaminated Soil  [PDF]
Seema Sharma,Alok Adholeya
Journal of Environmental Science and Technology , 2012,
Abstract: This study was conducted to isolate and characterize Cr(VI) [chromate] reducing bacteria from soil contaminated with tannery effluent (Kanpur, India) and evaluate these bacteria for Cr(VI) reduction activity. A comparative growth and reduction study was conducted in AMM (acetate minimal media; considering acetate as an economical and easily available carbon source) and in the tannery effluent for further possible application to remove Cr(VI) from the tannery effluent and other contaminated environment. The promising results encourages for the development of cost effective and user friendly bioremediation technology for tannery industry. Three bacteria (B2, B4 and B9) possessing ability to grow and reduce 1.24 mg L-1 of Cr(VI) below the detection limit within 24 h in absolute tannery effluent without any amendment, were evaluated for their reduction property in LB (Luria Bertani) broth media amended with 50, 100 and 200 mg L-1 of Cr(VI) concentrations. All three bacteria were gram positive and belong to the genus Bacillus. In a comparative Cr(VI) reduction study in three different media (LB, AMM and tannery effluent), isolate B9 kept the activity non-significantly different, irrespective of the type of media. However, isolate B4 showed significant influence of the media on its reduction ability. The independent growth study of these isolates distinctly indicates that tannery effluent is preferred over AMM; however, activity and growth were not linked to these isolates. The subsequent time course study further reveals their relevance and potential for application in environmental samples.
Bioremediation of chromium in tannery effluent by microbial consortia
JF Benazir, R Suganthi, D Rajvel, MP Pooja, B Mathithumilan
African Journal of Biotechnology , 2010,
Abstract: Chromium is the most toxic and common among the heavy metal pollutants of industrial effluents. In the present work the chromium remediation ability of Bacillus subtilis, Pseudomonas aeruginosa and Saccharomyces cerevisiae in consortia and in their immobilized forms was studied and their efficiencies were compared. Flame Atomic Absorption Spectroscopy and diphenyl carbazide method was used to quantify chromium in the effluent. The chromium content of the effluent was around 770 mg/l before remediation, after which it reduced to 5.2 – 5.7 mg/l. The best activity was observed by S. cerevisiae - P. aeruginosa consortia, followed by immobilized beads of S. cerevisiae and S. cerevisiae - B. subtilis consortia.
M. Nouri Sepehr, S. Nasseri, M. Mazaheri Assadi and K. Yaghmaian
Iranian Journal of Environmental Health Science & Engineering , 2005,
Abstract: Recently laboratory studies had recognized the capability of alge, fungi, and bacteria in the removal of heavy metals from industrial effluent. In this research, growth of Aspergillus oryzae in the tanning house effluent, and its capability in chromium bioremoval were assessed. Aspergillus oryzae can grow in different concentration of Cr+, 120-1080 mg/l. Maximum biomass growth and chromium removal rate at pH, 3.3, Cr+3 concentration equal to 240 mg/l and inoculum size equal to 0.12% (dry weight) were 0.25% (dry weight ) and 94.2%, respectively. Effects of various factors such as pH, temperature, shaking velocity and nutrients were also investigated. At optimum conditions (ie: pH=5; temperature=30oC, shaking velocity = 150 rpm, and nitrogen source of dihydrogen ammonium phosphate concentration=0.3%), biomass growth and chromium removal rate were found as 0.45% of dry weight and 99.8%, respectively. Effect of detention time showed that after 30h, biomass growth and chromium removal rate were 0.28% and 97.6%, respectively. Statistical studies on factors such as pH, temperature, shaking velocity, type and concentration of nutrients on the “biomass growth” and “residual chromium”, showed that all of the factors had significant effects ( α = 0.05, P < 0.001 ). Therefore A.niger capable grow in the tannery industries effluent with 240 mg/l chromium and 97.6% chromium removal rate .
Recovery of Chromium (III) from Tannery wastewater
Journal of Applied Sciences and Environmental Management , 2003,
Abstract: Three aqueous oxidants, Hydrogen peroxide, Sodium Hypochlorite and Calcium Hypochlorite were employed independently in oxidizing Chromium (III) containing tannery wastewaters to soluble chromate (CrO42-) under alkaline conditions. The amount of chromate recovered was determined via spectrophotometry. Hydrogen peroxide was potentially a suitable oxidant as it could recover chromate (CrO42-) up to 98% (from synthetic Cr3+ solution) and 88% (from effluent I). The percentage recoveries by the hypochlorites were lower than those by hydrogen peroxide i.e. for NaOCl the recoveries were up to 94% (from synthetic Cr3+ solution) and 67% (from effluent I), similarly for Ca(OCl)2 90% (from synthetic Cr3+ solution) and 49% (from effluent I). For all three oxidants complete (100%) recovery could not be achieved despite different experimental conditions (temperatures and oxidation time). The results clearly indicate that hydrogen peroxide is the most efficient among the three oxidants. Journal of Applied Sciences and Environmental Management Vol. 7(2) 2003: 5-8
Impacts of Chromium from Tannery Effluent and Evaluation of Alternative Treatment Options  [PDF]
Alebel Abebe Belay
Journal of Environmental Protection (JEP) , 2010, DOI: 10.4236/jep.2010.11007
Abstract: The paper has focused on the challenges/impacts of tannery effluent and evaluates the alternative treatment options used to treat, recover or recycle chromium from the waste water. The paper was done entirely on secondary data by consulting literature sources including scientific journals, chapters of books, conference report papers and websites. The results of this review paper indicated that chromium is highly toxic and carcinogenic to human beings, animals, plants and the general environment (soil and water sediment). It is found out that chrome is the primary threat when ever tanning industry comes in to practice. Though many treatment options were evaluated to prevent its consequence on the environment, neither of them could achieve to treat or recover chrome 100%. Treatment options are either; inef-ficient, complicated, energy demanding, costly or applicable to a certain parts of the world due to technology or skilled man power demand. Therefore, to tackle this serious challenge stringent environmental regulation with law enforce-ment has to be exercised to use better treatment system which is widely applicable. Polluters must also know the envi-ronmental cost of their industry and treated according to polluter pay or precautionary principles. Moreover, the gen-eral public has to be aware of it and all concerned organizations and governments has to work hand in hand to reach zero discharge level or at least to attain the EPA chrome discharge limit
Determination of Chromium in Tannery Effluent and Study of Adsorption of Cr (VI) on Saw dust and Charcoal from Sugarcane Bagasses  [PDF]
T. P. Dhungana,P. N. Yadav
Journal of Nepal Chemical Society , 2009, DOI: 10.3126/jncs.v23i0.2102
Abstract: Spectrophotometric method using diphenylcarbazide as a colour developing reagent has been used to analyze the chromium content in tannery effluent located in Bara and Parsa districts of Nepal and Sirsiya River which is an ultimate drainage of these waste water streams. The adsorption of hexavalent chromium from aqueous solution onto formaldehyde treated sawdust and charcoal of sugarcane begasses has been investigated at various Cr(VI) concentrations of 5-40 mg/L and pH values. From the experimental observations, it has been found that chromium can be removed quantitatively at the equilibrium pH range of around 1 and the adsorption behavior revealed to follow Langmuir and Freundlich adsorption isotherms.
Efficacy of Indigenous Bacillus Species in the Removal of Chromium from Industrial Effluent  [PDF]
Ali Abbas Qazilbash,Rani Faryal,Kokab Batool Naqvi,Safia Ahmad
Biotechnology , 2006,
Abstract: This study was designed to ascertain the effectiveness of isolated indigenous Bacillus species to remove chromium from industrially polluted effluents, through a series of effluent biotreatment regimen. Using microbiological techniques, 6 Bacillus strains were isolated, characterized and labeled QIP 1-6. All strains displayed maximum growth on media with a Cr concentration of 400 ppm. Strains QIP 1 and 5 showed maximum resistance to chromium showing moderate growth at 900 ppm of Cr. Following optimization, strain QIP 1 removed 46.81% of the Cr6+ and QIP 5 removed 42.50% of the chromium at the same concentration over the same incubation period, as determined through atomic absorption spectroscopy. Following different biotreatment regimens, biotreatment C1-filtered effluent inoculated with strain QIP 1, incubated under optimum conditions, showed maximum Cr6+ removal (10.29%) after 48 h. Interestingly, the second highest removal of Cr6+ (8.94%) occurred in the untreated, unfiltered raw effluent (D) after incubation for 48 h. Significant (p<0.05) strong positive correlation patterns emerged between these two regimen, as well as between regimen B 1-filtered effluent inoculated with strain QIP 1, but incubated under un-optimized conditions-and regimen D. The study revealed that intrinsic bioremediation does occur naturally and that it is quite possible for a consortium of Bacillus species to work more effectively at removing the HM from the contaminated sites, than a single isolate, thereby reducing the labor intensive work involved.
Plasmid Mediated Chromate Resistance in Bacteria Isolated from Industrial Waste
Sikander Sultan,Shahida Hasnain
Pakistan Journal of Biological Sciences , 2005,
Abstract: In order to study the genetic basis and mechanism of chromate resistance in chromate resistant bacteria, conjugal transfer as well as curing of plasmids in these bacteria and its effect on chromium uptake are being investigated. From the effluent of Shafiq Tannery, Kasur, Pakistan, four bacterial strains STCr-1, STCr-2, STCr-3 and STCr-4 which could endure 40 mg mL-1 of potassium chromate in nutrient agar medium were isolated. All of them were gram negative, aerobic and motile rods. One strain STCr-1 was identified as Ochrobactrum species by 16S rRNA gene sequence homology. Each strain harboured a single conjugative plasmid, which conferred resistance to chromate. Maximum plasmid transfer was recorded after 24 h of mating except for plasmid residing in STCr-3 (pSH1322), which transferred maximally after 16 h of mating. The plasmids harboring STCr-1 (pSH1320), STCr-3 (pSH1322) and STCr-4 (pSH1323) manifested highest transfer frequency at donor:recipient ratio 1, while plasmid resident of STCr-2 (pSH1321) preferred donor:recipient ratio 5. Transfer frequency of plasmids pSH1320 and pSH1322 was maximal at 28°C and that of pSH1321 and pSH1323 at 37°C. Optimum pH for plasmid transfer was 8 for these plasmids except pSH1320, which opted for pH 6 or 7. Curing of chromate resistant plasmids from these strains was achieved with SDS at high temperature and curing of plasmid was associated with the loss of chromate resistance phenotype. A comparison of Cr uptake by the parental strains and their cured derivatives revealed that plasmids in these strains express high level resistance to chromate by exerting stringent control on the accumulation/uptake of Cr.
Biochemical stress of chromium in tannery effluents on the fresh water fish, tilapia mossambica(pisces)  [PDF]
R S Sreenivasan,P Krishna Moorthy , M Deecaraman
International Journal of Biological and Medical Research , 2011,
Abstract: Tannery effluent was brought from the Puliyankannu Village, SIPCOT Industrial Estate of Ranipet, Tamil Nadu, India. The fresh water teleost, Tilapia mossambica was chosen as experimental animal. Chromium is the major constituent of tannery effluent, which is the heavy metal and highly toxic to aquatic fauna. The physico-chemical characteristic and oxygen consumption of tannery effluent were estimated. Histological changes in the liver and muscle of the experimental fish were observed. In the present investigation, the changes of histological structure of liver and muscle of Tilapia mossambica under chromium stress and toxic stress of tannery effluents on agriculture aquatic fauna were studied and the results are reported in this paper.
Physico-Chemical and Microbiological Characterization of Soils Laden with Tannery Effluents in Sokoto, Nigeria
AB Rabah, ML Ibrahim
Nigerian Journal of Basic and Applied Sciences , 2010,
Abstract: Changes in microbial community content as well as physico-chemical properties of soil contaminated with tannery effluents in Sokoto metropolis were determined using standard procedures. The results showed that the soil sample contained a variety of microorganisms which include Bacillus cereus, Bacillus subtilis, Pseudomonas aeroginosa, Proteus mirabilis, Serratia marcensces, Escherichia coli, Streptococcus pyogenes, Klebsiella pneumoniae, Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Penicillium notatum, Mucor pusillus as well as Fusarium sporotrichioides. It also revealed high counts of bacteria and fungi in all the sampling sites. The viable count of bacteria was in the range of 8.60±1.80 – 8.70±0.52 ×105cfu/g while that of fungi was 1.70±0.30 – 2.0±0.10 × 104cfu/g. Similarly, it revealed high levels of sulphide (0.35-0.44mg/g), ammonia (0.40-0.60mg/g), and chromium (0.20-0.26mg/g) in all the sampling sites. These levels exceeded the tolerable levels set by the Federal Ministry of Environment. The presence of these microorganisms and chemical substances pose a potential threat to the local inhabitants of these areas. KEYWORDS: Physico-chemical, Microbiological, Soil, Tannery, Effluent, Sokoto
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