Histopathological analysis of selected organs of Oreochromis niloticus due to sub-lethal industrial effluents exposure.

On a daily basis, our environment is exposed to tons of a composite of industrial effluents, which has a negative impact on commercial fish production and, as a result, on humans. Present study was designed to evaluate the acute, sub-chronic, and chronic toxicity of a composite of raw industrial effluent from Sunder Industrial Estate in the freshwater fish Oreochromis niloticus biosystem by investigating at the histopathological changes in different organs such as heart, kidney, and muscle after exposure. Fish was exposed to 1/3 rd , 1/5 th and 1/10 th of predetermined LC 50 . Significant histopathological alterations in heart (myocarditis, pericardium bending and lifting) kidney (renal tube degeneration, glomerulus structural alteration and necrotic proximal tubule) and muscle (inflammation, atrophy and tumor) were observed in treated groups. After the sub-lethal exposure histological alteration index (HAI) was highest in chronic group as compared to the acute and sub-chronic group as HAI group D ? HAI group C ? HAI group B. Moreover physic-chemical parameters of water were found to be out of the range of the APHA standard approach.

A study on the utilization of rice husk as a biosorbent material for Cr (VI) removal from industrial effluent

Purpose: To study Cr (VI) removal from waste water using chromium-resistant bacterial strains in combination with rice husk. Methods: Two strains of Exiguobacterium sp. resistant to chromium (VI) were applied in the present work. Rice husk (RH) was used as an agricultural waste for Cr (VI) removal. The elimination of Cr from the husk was chemically facilitated using hydrochloric, sulphuric and citric acids, as well as formaldehyde and potassium dihydrogen phosphate Investigation of optimum physical factors such as pH, temperature, shaking speed and biomass concentration on Cr (VI) removal was carried out using citric acid-processed rice husk alone, and in combination of bacterial strains. Fourier transform infra-red (FTIR) spectroscopy was performed to determine the contributions of different functional groups involved in Cr (VI) binding. Scanning electron microscopy (SEM) of treated and untreated RH was also performed. Results: Citric acid-processed RH was most effective in the removal of chromate (97.3 %). The two bacterial strains combined with rice husk proved highly efficient in Cr (VI) removal from sterile and non-sterile industrial effluents. FTIR spectra showed the involvement of esters, amines and aliphatic functional groups in Cr (VI) binding, while SEM displayed the damaging effects of Cr (VI) on the surface of RH; however, bacterial inoculation minimized the damage. Conclusion: Exopolysaccharides from Exiguobacterium strains and citric acid-processed rice husk demonstrated high efficiency for Cr (VI) removal. Hence, RH with these bacterial strains are potential biosorbents for control of heavy metal contamination arising from industrial effluents.

Methyl Orange Biodegradation by Immobilized Consortium Microspheres: Experimental Design Approach, Toxicity Study and Bioaugmentation Potential

Methyl orange (MO) is categorized among the recalcitrant and refractory xenobiotics, representing a significant burden in the ecosystem. To clean-up the surrounding environment, advances in microbial degradation have been made. The main objective of this study was to investigate the extent to which an autochthonous consortium immobilized in alginate beads can promote an efficient biodegradation of MO. By employing response surface methodology (RSM), a parametric model explained the interaction of immobilized consortium (Raoultella planticola, Ochrobactrum thiophenivorans, Bacillus flexus and Staphylococcus xylosus) to assimilate 200 mg/L of MO in the presence of 40 g/L of NaCl within 120 h. Physicochemical analysis, including UV-Vis spectroscopy and FTIR, and monitoring of the degrading enzymes (azoreductase, DCIP reductase, NADH reductase, laccase, LiP, MnP, nitrate reductase and tyrosinase) were used to evaluate MO degradation. In addition, the toxicity of MO-degradation products was investigated by means of phytotoxicity and cytotoxicity. Chlorella vulgaris retained its photosynthetic performance (>78%), as shown by the contents of chlorophyll-a, chlorophyll-b and carotenoids. The viability of normal lung and kidney cell lines was recorded to be 90.63% and 99.23%, respectively, upon exposure to MO-metabolic outcomes. These results reflect the non-toxicity of treated samples, implying their utilization in ferti-irrigation applications and industrial cooling systems. Moreover, the immobilized consortium was employed in the bioremediation of MO from artificially contaminated agricultural and industrial effluents, in augmented and non-augmented systems. Bacterial consortium remediated MO by 155 and 128.5 mg/L in augmented systems of agricultural and industrial effluents, respectively, within 144 h, revealing its mutual synergistic interaction with both indigenous microbiotas despite differences in their chemical, physical and microbial contents. These promising results encourage the application of immobilized consortium in bioaugmentation studies using different resources.

Mathematical Modeling of the growth of Acinetobacter baumannii YNWH 226 on Azo dye Congo red

Industrial effluents (Azo dyes) are brightly coloured, making their disposal into receiving waters undesirable not only because many Azo dyes and their breakdown products are toxic to aquatic life and mutagenic to humans, but also because many Azo dyes and their breakdown products are harmful to aquatic life due to the presence of aromatics and metals, chlorides, and other chemicals. Various kinetic models, including modified Gompertz, Baranyi-Roberts, modified Richards, Von Bertalanffy, modified Logistics, modified Schnute, Buchanan three-phase, and the most recently presented Huang, were used in this study. Based on statistical tests, the modified Schnute model provided the best fit, with the lowest values for RMSE and corrected Akaike Information Criteria (AICc), the greatest value for adjusted R2, and the closest to unity for both Accuracy and Bias Factor. The Modified Schnute parameters such as λ (lag time), µmax (maximum specific bacterial growth rate) and curve fitting parameters α and β (Constant), were found to be -4.39 (95% confidence interval of -77.58 to 68.79), 57.00 (95% confidence interval of -2854.30 to 2968.30), 0.78 (95% confidence interval of -0.34 to 1.89) and 0.96 (95% confidence interval of -0.85 to 2.78, respectively.

Effect of Ota Industrial Estate effluents on surface water quality of Oruku River, Ota, South Western Nigeria

The effect of industrial effluents on surface water quality of Oruku River was investigated in this study by analyzing selected water quality indicators such as pH, dissolved oxygen (DO) and total dissolved solids (TDS) were examined amongst other physicochemical parameters using standard methods. Results show that, average pH of the surface waters ranged from 5.53±0.31 to 6.23±0.45 with SR3 having the highest value. This indicates that all the water sources were alkaline. The effluents had an average pH range of 5.95 ± 1.12 to 6.40 ± 0.48. A comparison of these average pH values with effluent quality standards indicated that the effluents pH were below limit (6.5-9.5). The average BOD levels in surface water ranged from 1.94 ± 0.95 for SR-4 to 3.78 ± 1.61 for SR-1. DO average values in surface water was found to be higher at SR-1 with a mean value of 5.36 ± 1.55 and lower at SR-2 with a mean value of 3.05 ± 0.68. The mean COD value for surface water ranged from 108.66 ± 73.03mg/L to 232.81 ± 155.46mg/L. SR-3 had the highest COD average value of 232.81 ± 155.46mg/L while there was a reduction at SR-5 to an average value of 108.66 ± 73.03mg/L. The high COD value in the surface water indicates that gross-organic pollution of the water source may be from other sources such as agricultural and urban run-offs.