Biodegradation of Tannic Acid, Chromium and Cadmium Present in Leather Industrial Effluents Using Microorganisms Isolated from Leather Industrial Sludge

The present work was aimed to isolate indigenous predominant adapted Bacterial strains from tannery waste which possess the ability to detoxify and degrade Tannic acid, Chromium and Cadmium from tannery effluent. Fifteen bacterial strains were isolated from tannery sludge samples out of which Paracoccus pantotrophus (Tannery Waste 15) and Bacillus velezensis (Tannery Waste 17) were found to be the most efficient isolates. Degradation of Tannic acid, Cadmium and Chromium were evaluated for the two selected isolates. Better degradation of heavy metals was recorded in co-cultured media on day 7. From the study, it is evident that both P. pantotrophus and B. velezensis have has the ability to degrade tannic acid with maximum degradation on day 7 and absorbance was found to be 0.915 and 0.383 respectively. The strain P. pantotrophus showed better tannic acid degradation than B. velezensis. Better degradation was observed with co-culturing of both the strains with absorbance of 0.274. Optimal cadmium degradation was observed on day 7 with OD 2.013 and 1.709 for B. velezensis and P. pantotrophus respectively. P. pantotrophus showed better cadmium degradation when compared to B. velezensis. Chromium degradation was maximum on day 7 and absorbance was 2.096 for P. pantotrophus and 0.560 for B. velezensis. The isolates recorded an acceptable reduction in the concentration of Tannin, Chromium and Cadmium in tannery effluent. The results of this showed that the isolates reduced the concentration of Tannin, Chromium and Cadmium present in the raw tannery effluent and suggest that the organisms can be used as a possible treatment of tannery effluents. Keywords: Bio-degradation, Bacillus velezensis, Paracoccuspantotrophus, Chromium, Cadmium, Tannic acid, Tannery effluent.

Biodegradation potential of immobilized bacteria in the treatment of Tannery Industrial effluents from industrial estates in Kano State, Nigeria

Industrial Effluents Samples from Gashash Tanneries (TAN1) in Bompai Industrial estate, Larabee Tannery Industry (TAN2) in Sharada Industrial estate and Z Tannery Industries (TAN3) in Challawa Industrial estate, Kano State, Nigeria were collected over a period of six months (August 2017 to January 2018) for assessing the biodegradation potentials of bacteria in the treatment of organic pollutants within the effluents. Bacteria were isolated from the effluents and immobilized on agar-agar. Different masses (5 g, 10 g, 15g, 20 g, and 25 g) of the bacteria were used in the treatment of 250 ml of the effluents for ten days in a shaker incubator (Gallenkamp-OC-4364-L) at the temperature 30 °C and speed of 60 rpm. Pre-treatment analysis of the effluents for Temperature, pH, Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Suspended Solid (SS) and Total Dissolved Solids (TDS) gives the following results; temperature (ºC) ranged (26.38±3.81-30.33±3.79); pH (5.35±1.57-9.00±0.78); BOD (13.85±6.42-38.75±16.20); COD (1406±208-3532±1373); SS (208±235-780±739) and TDS (266±253-5276±2971). No statistical differences (p ≤ 0.05) was observed for all the results among the different industries. The bacterial isolates were identified as Neisseria spp, Bacillus cereus, and Staphylococcus aureus, in TAN1, TAN2, and TAN3, respectively. After treatment of the effluent with the different masses of the isolated bacteria, the mean level of BOD was found to range as (0.55±0.36-6.92±5.49); COD (ND-3134±1595); SS (18±022-898±672) and TDS (4±002-83±078). The results of Post-treatment analysis showed that there is overall decrease in the levels of the parameters determined when compared with that of the pre-treatment. The overall percentage reduction of the immobilised bacteria in the treatment of the respective effluents was in the order TAN2 (72%)>TAN1 (70%)>TAN3 (62%). Hence, the immobilized bacteria are having higher biodegradation potential for the treatment of the tannery effluents.

BIOREMEDIATION OF CHROMIUM (VI) BY A MICROBIAL CONSORTIUM ISOLATED FROM TANNERY EFFLUENTS AND THEIR POTENTIAL INDUSTRIAL APPLICATION

West Bengal has several leather industries and as such huge amount of leather are processed every year. The tannery effluents are discharged into the land and open water causing soil and water pollution respectively. Chromium is one of the most toxic inorganic contaminants which is well known for its carcinogenicity. Thus, our study focuses on investigating the bioremediation potential of common microflora isolated from tannery wastewater. In our study, Isolate 1 has the highest ability to reduce chromium (Cr6+) as compared to others. Isolate 4 has the highest protease, lipase and leather degradation activities. Isolate 1 shows the maximum keratinase activity making it an effective strain for keratinase production. Also, it has been found that pH 8 and temperature 40 °C was most suitable for keratinase production. Owing to the multidimensional ability of these two isolates, they were identified by 16S rRNA sequencing and it reveals that Isolate 1 and Isolate 4 belong to Bacillus cereus F4810/72 and Brevibacillus brevis F4810/72 respectively. Thus, this study establishes the role and efficiencies of these microorganisms in combatting pollution, particularly in the water bodies in which harmful chemicals leak regularly owing to improper waste management by various industries.

Assessment of significant metals in effluents, soil, and pond water of tanneries south of capital of Sudan state

In the present study, impact of tannery effluents and their subsequent on accumulation of some metals (Ca, K, Na, Mg, Cl, S, Cr, Fe, Mn, Pb, and Zn) in water and soil samples in and around South Khartoum industrial area, Khartoum-Sudan were studied. Concentration of metals in tannery effluents (SA), adjacent contaminated pond water (SB), Soil (SC), and uncontaminated water (SD) were assessed by atomic absorption photometer. The results showed high levels of Ca, K, Na, Mg, Cl, S, Cr, Fe, Mn, Pb, and Zn within the water from all sampling point (SA, SB and SC). The investigation exhibited that tanneries wastewater has high mean concentrations of Cr, Fe, Mn, and Pb in all sampling point of effluent, pond water, soil, and uncontaminated water, except Zn which is high only in soil sampling point (SC). The significant metals accumulation displayed a pattern of mean concentration as follow: Soil > Effluent >contaminated pond water > Un contaminated water. Significant metals toxicity levels within the totally different sampling points were compared with water from WHO. Mean metal concentrations in un contaminated water were among the allowable limit set by WHO except for Magnesium (Mg). The comparison indicated that soil (SC) within the neighboring industrial area accumulated metals, enhanced levels of toxic of metals such as Cr, Ni, Zn and Pb, which also demonstrated higher concentration levels in the adjacent contaminated pond water samples. increased levels of poisonous, that additionally incontestable higher concentration levels within the contaminated pond water.

Sub-Chronic Toxicity Evaluation of Tannery Waste Water to Clarias gariepinus Juveniles

This paper was conducted to investigate the sub-chronic toxicity of tannery effluents sourced from Challawa industrial estate Kano, Nigeria using Clarias gariepinus. The study covered physicochemical parameters, haematological, and biochemical stress enzymes assessments. The water quality results revealed mean value of Temperature (29.92±1.93oC), pH (8.14±0.85), DO (1.60±0.38mg/l), BOD (0.77±0.16mg/l), Salinity (7.75±0.60mg/l), Nitrate (1.19 ± 0.05mg/l) and Phosphate (16.48±0.85mg/l). After termination of 21 days sub-chronic test, haematological and biochemical changes analysed were generally considered significantly different (P<0.05) within the treatments. The haematological indices revealed a decrease and sudden increase in concentration of estimated values of PCV, Hb, RBC, MCHC and MCH, while WBC and MCV fluctuated. These may be attributed to stress, the duration of exposure and levels of pollutants in the effluent. Furthermore, oxidative stress enzymes followed an order of SOD > CAT > GSH. This could be due to level of pollutants in the effluent. The results of the data indicated tannery effluent to have a toxic effect on the experimented organism. The information calls for a more enrich toxicity testing that should involve wide range of organisms. It should entail reproductive aspects of the species, detail relationship and enhanced methodological procedures.

Chromium removal from tannery effluents by adsorption process via activated carbon chat stems (Catha edulis) using response surface methodology

Objective In tannery processing, water consumption is high, which generates wastewater as a by-product and numerous pollutants such as chromium heavy metals that make adverse effects of water bodies and the surrounding environment. This study analyzed, chromium (VI) removal from wastewater through activated carbon chat stem was investigated. Adsorption is a common treatment method via activated carbon due to its cost-effective, profitable, and removal efficiency of these heavy metals. Results The proximate analysis of moisture content of chat stem has 6%, activated carbon ash content of 17.35%, volatile materials of 20.12%, and fixed carbon contents of 56.53%, which are well-matched the standards quality of activated carbon. As the process parameter varies, the increment of the chromium removal efficiency was from 62.5 to 97.03%. The maximum adsorption efficiency was observed at 30 g/L dosage of the adsorbent, at pH 4, and contact time at 180 min of activated carbon from chat stem waste was found 97.03%. FTIR was used to characterize the surface of the chat stem before and after adsorption. Langmuir and Freundlich are used for short contact time’s adsorption isotherm 0.9839 and 0.9995 respectively, which conformed, no visible change in the corrosion state.

Genetic Variability Screening of the Leptolyngbya Boryana with Expressed ChrR Gene for the Biotransformation of Cr (VI) to Cr (III) Reduction

Chromium is well known pollutant for its mutagenicity, and carcinogenicity in humans. Excessive uses of chromium in leather tanning industries, stainless-steel production, and wood preservatives have resulted as chromium contamination in soil and water. This investigation indicates the effective use of Leptolyngbya boryana as an eco-friendly option to overcome Chromium (VI) toxicity in tannery effluents. The main objective of this research was to find out ChrR gene and its variability in the context of Cr (VI) stress. This is a novel study in the relation of Leptolyngbya boryana. Industrial polluted soil samples were collected and processed according to the standard protocols for ChrR variation and 16S rRNA gene. DNA was isolated and amplified through PCR. Amplified DNA was sequenced and aligned with the known sequences. In this study a strong co-relation was established in the nucleotide sequences of ChrR and 16S rRNA genes. MIC was determined for Cr (VI) and pure strains of Leptolyngbya boryana were identified and isolated from soil. In the present study presence of ChrR gene variability was recorded in Leptolyngbya boryana which is a cyanobacterium in the soil of tannery effluent under Cr (VI) stressed condition and its gene variability was confirmed by sequencing. We can conclude that Leptolyngbya boryana strain could be eco-friendly option to overcome Chromium (VI) toxicity in tannery effluents.

Model-Driven Strategies for Sulfide Control in a Regional Wastewater System Receiving Tannery Effluents in Portugal

Ageing infrastructure are a concern for many wastewater utilities. This is accentuated with the presence of hydrogen sulfide within the sewer headspace, known to induce concrete corrosion, toxicity and odours. Some industrial effluents contain significant sulfide concentrations, however most field studies in the literature refer to domestic networks, or lab/pilot scale sulfide abatement strategies for varied effluents. Hence, the objectives of this work are: (1) To obtain data regarding the evolution of sulfides in a full-scale industrial sewer system in Portugal, receiving wastewater from a number of tanneries; (2) model their fate within the system and (3) experimentally evaluate sulfide precipitation with iron salts. Field work evidenced heavily sulfide loaded effluents, exceeding by far literature values for sewer systems. Modelling was carried out based on the AeroSept+ model, specifically calibrated to this type of effluent. Results showed the model was capable of reproducing the overall levels of sulfide in wastewater and H2S in the sewer headspace, while allowing insights into industrial discharges, originating a set of proposed interventions for sulfide abatement. This may be carried out by iron salts addition, in a ratio of 2.75:1, at existing monitoring stations. This approach was fundamental for an affordable performance assessment, under considerable uncertainty.