Effects of Oil Refinery Effluents on Selenastrum capricornutum PRINTZ

Laboratory-based bioassay experiments using Selenastrum capricornutum PRINTZ as the test organism were conducted to evaluate the potentiality of refinery effluents to sustain algal growth. The raw effluents were remarkably toxic to the test alga, but satisfactory algal growth occurred in (diluted) 0.01 % effluents. The effluents from subsequent treatment stages required much less dilution to eliminate the toxicity. This study implicates oil and phenol in the reduction of algal growth in refinery effluents. A highly significant negative correlation was found between the final yield of the test alga and the concentration of oil or phenol in the culture suspension. The bioassay experiments therefore point to the toxic nature of refinery effluents. On the basis of these findings it is recommended that proper dilution of refinery effluents is necessary before they are discharged into any body of water.     

A comparison of organochlorine removal from bleached kraft pulp and paper-mill effluents by dehalogenating Pseudomonas,Ancylobacter and Methylobacterium strains

The relative importance of each of three dechlorinating species to overall organochlorine removal from bleached kraft-mill effluents (BKME) was assessed. Ancylobacter aquaticus A7, Pseudomonas P1, and Methylobacterium CP13, strains indigenous to a BKME treatment system, were tested for growth on chlorinated acetic acids and alcohols, and for adsorbable organic halogen (AOX) reduction in batch cultures of sterile BKME from three sources. A. aquaticus A7 exhibited the broadest substrate range, but could only affect significant AOX reduction in softwood effluents. Methylobacterium CP13 exhibited a limited substrate range, but was capable of removing significant amounts of AOX from both hardwood and softwood effluents. By contrast, Pseudomonas sp. P1 exhibited a limited substrate range and poor to negligible reductions in AOX levels from both effluent types. Mixed inocula of all three species combined and inocula of sludge from mill treatment systems removed as much AOX from softwood effluents as did pure populations of Methylobacterium CP13. When BKME was hydrolysed prior to AOX analysis, the subsequent estimates of recalcitrant, or non-hydrolysable, AOX levels were far less variable than their counterpart total AOX measures. It is suggested that this is a relevant and useful measure of AOX for biodegradation studies.     

Reuse of Textile Wastewater after Treatment with Isolated Bacteria from Oued Hamdoun River

Industrialization is a boon for developing countries such as Tunisia. However, textile effluents that are being discharged are environmental pollutants, extremely toxic to plants and other living organisms, including humans. The current study was conducted to determine the phytotoxic effect of textile effluents, collected near an industrial zone in the center of Tunisia (Ksar Helal), on the germination and various growth indices of durum wheat (Triticumaestivum L.). Results showed that textile effluent treatments reduced significantly the percentage of seed germination and slowed its kinetic as compared with control. Roots and leaves were also significantly reduced. The phytotoxicity was highly reduced from textile effluents after aerobic biotreatment with bacteria. It can be concluded that the biological treatment process of textile wastewater might serve as a fertilizer production that is able to improve the growth of plants. These results are encouraging in the context of developing a low-budget technology for the effective management of these effluents.     

Antibiotic susceptibility profiles of some <Emphasis Type="Italic">Vibrio</Emphasis> strains isolated from wastewater final effluents in a rural community of the Eastern Cape Province of South Africa

Background  

To evaluate the antibiogram and antibiotic resistance genes of some Vibrio strains isolated from wastewater final effluents in a rural community of South Africa. V. vulnificus (18), V. metschnikovii (3), V. fluvialis (19) and V. parahaemolyticus (12) strains were isolated from final effluents of a wastewater treatment plant (WWTP) located in a rural community of South Africa. The disk diffusion method was used for the characterization of the antibiogram of the isolates. Polymerase chain reaction (PCR) was employed to evaluate the presence of established antibiotic resistance genes using specific primer sets.     

Biodegradation and detoxification of dyes and industrial effluents by Ganoderma weberianum B-18 immobilized in a lab-scale packed-bed bioreactor

White-rot fungi are considered to be promising biotechnological tools to complement or replace the current technologies for the treatment of effluents from textile production plants. The aim of this work was to investigate the decolorization capacity of Ganoderma weberianum B-18 in solid state fermentation with sugarcane bagasse as a substrate and ligninolytic inducer as well as to decolorize and detoxify industrial effluents by this strain in a laboratory scale packed-bed bio-reactor. The results demonstrated that G. weberianum B-18 indeed showed to possess decolorization capacity in solid state fermentation with sugarcane bagasse supplemented with synthetic dyes. Moreover, fungal biomass of G. weberianum B-18 immobilized in sugarcane bagasse in a packed-bed bioreactor was shown to efficiently decolorize and detoxify different dyes and authentic industrial effluents in semi-continuous conditions. In this decolorization process, laccase enzymes secreted by the fungus played the main role. Hence, a packed-bed reactor with G. weberianum B-18 immobilized in sugarcane bagasse seems to be a suitable system for the further development of an efficient bioprocess for large-scale treatment of dye-containing wastewaters.     

The effect of cooling seawater effluents of a power plant on growth rate of cultured Gracilaria conferta (Rhodophyta)

The effect of cooling seawater effluents of a power plant on the growth rate of Gracilaria conferta in tanks has been studied, as a possible solution for the decrease in the winter growth rate in ambient seawater tanks. The Gracilaria cultures did not survive more than 2–8 weeks in the power plant effluents during the one-year-long repeated experiments. The major reason was the high accumulation of copper, iron, lead and chromium from the power plant effluents as compared to concentrations in Gracilaria cultured in ambient seawater. The survival increased and the copper accumulation decreased significantly when the effluents were passed through an Ulva biofilter.     

Single cell protein production from bagasse pith pretreated with sodium hydroxide at room temperature

Summary Previous publications have revealed that a pretreatment of lignocellulosic wastes is necessary if they are to be employed as the hydrocarbon source of single cell protein production. A hot alkaline treatment is the most common.We have treated sugar cane bagasse pith with 1% NaOH solution at room temperature, at a NaOH/pith ratio of 10%. Different contact times were used in the experiments. The shortest contact period required for maximum protein production was 24 h at 25° C. A mixed culture of Cellulomonas sp. and Bacillus subtilis was used in the experiments. The values obtained for hemicellulose and cellulose in the treated pith did not differ greatly from those of untreated pith, in contrast the amount of lignin was 33% lower in the treated pith. The effect of reutilization of the alkaline liquor used for the pretreatment of pith upon protein production was also investigated. With four recyclings, there was a NaOH saving of 34.4 kg per 100 kg produced protein as compared to when the liquor was only used once.The quality of the resulting effluents, as measured by the chemical oxygen demand (COD), proved to be very similar for both types of treatment.     

Biotreatment of pulp mill bleachery effluents with the coelomycetous fungusStagonospora gigaspora

Summary The coelomyceteStagonospora gigaspora degrades lignin derivatives within pulp mill bleachery effluents. Besides dechlorination, 90% of the color was removed from CEH bleachery effluents. Lignin derivatives in the effluents of the EOP bleaching stages revealed more persistent against fungal attack. Toxicity of both effluents was diminished significantly byS. gigaspora.     

SCP from pineapple (Ananas sativa Schutt)

Summary Pineapple cannery effluents are available nearly round the year. The effluents are rich in microbially utilizable nutrients and when supplemented with ammonia support good growth of Candida utilis and Hansenula sydowiorum.The latter strain produces 45.0 g/l, 21.9 g/l, 1.5%, and 6.4% of cell biomass, protein, DNA, and RNA respectively in batch fermentations of such a medium. Amino acid profile, digestibility, NPU, and actual feed experiments confirm the applicability of the product. Concomitantly, a 90% reduction in BOD₅ value of the effluent can be effected during this process which otherwise proves to be troublesome.     

Effects of Crude and Bioremediated Thermal Power Plant Effluents in Brassica Juncea

Crude phenol and cyanides are the major components of the effluents discharged by industries involved in the manufacture of many synthetic inorganic and organic compounds, pharmaceuticals, electroplating units, and thermal power plants.

In this study, an effort was made to use effluents as manure. The effect of various amendments (10, 40, 70, and 100%) of bioremediated and crude effluents was checked on plants of Brassica juncea. Roots, shoot lengths, and the mean dry weights were maximum in the plants irrigated with 10% treated and 10% crude effluent as compared to the control plants. Total plant phenolics increased with an increase in the amendment of the effluents in the plants irrigated with bioremediated as well as crude effluents. Applications of lower amendments of treated and untreated effluents in Brassica juncea improved the chlorophyll levels in the experimental plants and the values obtained were similar to the control plants. Effect of bioremediated and crude effluents on antioxidant enzymes of Brassica juncea showed a differential effect. The activity of antioxidant enzymes peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD) was observed to increase with an increase in the effluent concentration.

Here we demonstrate that the industrial effluents, when bioremediated of their harmful components, can also serve as a nourishment for plants, which can further help in the rehabilitation of wastelands.     

Synergistic action of azoreductase and laccase leads to maximal decolourization and detoxification of model dye-containing wastewaters

The azoreductase PpAzoR from Pseudomonas putida shows a broader specificity for decolourization of azo dyes than CotA-laccase from Bacillus subtilis. However, the final products of PpAzoR activity exhibited in most cases a 2 to 3-fold higher toxicity than intact dyes themselves. We show that addition of CotA-laccase to PpAzoR reaction mixtures lead to a significant drop in the final toxicity. A sequential enzymatic process was validated through the use of 18 representative azo dyes and three model wastewaters that mimic real dye-containing effluents. A heterologous Escherichia coli strain was successfully constructed co-expressing the genes coding for both PpAzoR and CotA. Whole-cell assays of recombinant strain for the treatment of model dye wastewater resulted in decolourization levels above 80% and detoxification levels up to 50%. The high attributes of this strain, make it a promising candidate for the biological treatment of industrial dye containing effluents.     

In vitro genotoxic evaluation of conventional bleached and biobleached softwood pulp mill effluents

The effluents of pulp and paper mills contain about 300 different chemical compounds; many of them are mutagens and clastogens. Genotoxic studies have shown that chlorination stage liquors are significantly more genotoxic, in the Ames Salmonella assay, than the other process of lignin extraction, and that lyophilized effluents are genotoxic in cultured mammalian cells. Since these effluents from conventional bleaching stages are genotoxic, Chilean industries are interested in changing this process to a less toxic one, such as biobleaching using enzymes. In this study, we tested the in vitro genotoxicity of two types of effluents: an effluent obtained from a conventional radiata pine kraft-bleaching process (effluent D) and one derived from a biobleaching process with hemicellulase (effluent B). Both effluents were tested without any concentration or purification steps in the Ames Salmonella assay (TA100) and in the micronuclei (MN) and sister chromatid exchange (SCE) tests in CHO cells. The results showed that neither effluent induced base pair substitution mutations in the Ames Salmonella assay, and neither increased the micronucleus frequency in CHO cells. But, both increased the SCE frequencies in CHO cells, showing that this assay is more sensitive than the other ones, and that the two effluents contained chemical compounds in amounts enough to induce in vitro genotoxicity measured by the SCE induction.     

Screening of white-rot fungi for efficient decolourization of bleach pulp effluents

Summary Several white-rot fungi collected in the South of Chile were evaluated for their ability to decolourize kraft pulp bleached effluents. Strain 158, recently identified as aRamaria sp., showed the highest potential for the biological treatment of E1 effluent: 90% of the colour was removed by this strain grown under air, with a similar rate and extent of decolourization asPhanerochaete chrysosporium, under oxygen.     

Agar yield and quality of Gracilaria chilensis (Gigartinales,Rhodophyta) in tank culture using fish effluents

Tank cultivation of Gracilaria using fish effluents has permitted a production of 48 kg m^–2 yr^–1 and can reduce the dissolved nitrogen loads in the seawater. We report the yield, gel strength, gelling and melting point of agar from Gracilaria cultivated in tanks with seawater previously utilized in intensive, land-based salmon cultures and compared to a control using directly pumped seawater, over a study period of 22 months. The results show that the highest agar yield (20 to 22%) was obtained when Gracilaria was cultivated with pure seawater as compared to the fish effluents. The gel strength, gelling and melting point were higher in the agar obtained from algae cultured with fish effluents. During the spring, the gel strength, gelling and melting point increased in tanks with fish effluents and decreased in tanks with a supply of pure seawater.     

Bacteriological Investigation of Alberta Meat-Packing Plant Wastes with Emphasis on Salmonella Isolation

The waste treatment facilities and final effluents of 11 meat-packing plants in the Province of Alberta were investigated primarily to determine the numbers of indicator bacteria and the presence of Salmonella. This was done to discover the efficiency of the treatment systems presently in operation in reducing bacterial numbers and to establish the need for disinfection and for bacterial standards for these effluents. Data obtained showed that the final effluents were of very poor quality bacteriologically, with numbers of indicator organisms comparable to those found in raw sewage. Primary treatment facilities were ineffective in reducing the numbers of these bacteria. The secondary treatment facility investigated achieved greater than a 99% reduction of indicator bacteria. Salmonella were isolated from the final effluents of 78% of the plants, including the plant using secondary treatment. In total, 21 Salmonella serotypes were isolated. Salmonella isolates were not antibiotic resistant, but certain coliform and fecal coliform isolates demonstrated resistance to chloramphenicol, tetracycline, and ampicillin.     

Detection of Giardia in Sewage Effluent1

Giardia sp. cysts were found at levels of 4,000–450,000/378,500 liters (100,000 gallons) in sewage effluents from three of seven sewage treatment plants in Sangamon County, Illinois, in June, July, and August 1981. Effluent from the positive plants is discharged into Lake Springfield (the present source of the city of Springfield's water supply) or the Sangamon River.     

A novel three-stage seaweed (Ulva lactuca) biofilter design for integrated mariculture

Seaweed biofilters have proven their usefulness in the treatment of fishpond effluents. However, their performance poses a dilemma: TAN (Total Ammonia N) uptake rate – and with it seaweed yield and protein content – is inversely proportional to TAN uptake efficiency. The ideal for a seaweed biofilter performance would be a high uptake rate together with high uptake efficiency. The novel three-stage seaweed biofilter design described here has solved this dilemma. The design used the finding that the performance of seaweed ponds depended on the flux of TAN through them, and that therefore effluents with reduced TAN concentration could provide the seaweed with a high TAN flux if the water flow increased proportionally. Effluents from a seabream fishpond were passed through a series of three successively smaller (25, 12.5 and 6.25 m², respectively) air-agitated Ulva lactuca ponds. The diminished inflow TAN concentrations to the second and third ponds of the biofilter system were compensated for by the increased water exchange rates, inversely proportional to their sizes. The biofilter performance was evaluated under several TAN loads. TAN was efficiently removed (85–90%), at a high areal rate (up to 2.9 g N m^-2 d^-1) while producing high protein U. lactuca (up to 44% dw) in all three stages, although with mediocre yields (up to 189 g fresh m^-2 d^-1). Performance of each seaweed biofilter pond correlated not with TAN concentration, but with areal TAN loads. The novel three-stage design provides significant functional and economic improvements in seaweed biofiltration of intensive fishpond water.     

A novel hybrid technology for remediation of molasses-based raw effluents

A novel three-step technology for treatment of four molasses-based raw industrial effluents, varying in their COD, color and turbidity is reported here. Sequential steps involved in this treatment are; (1) sonication of the effluents, (2) whole-fungal treatment of these by a ligninolytic marine fungus and (3) biosorption of the residual color with heat-inactivated biomass of the same fungus. Sonication reduced the foul odor and turbidity of the effluents. It increased biodegradability of the effluents in the second stage of treatment. Laccase production in the presence of all the four effluents was directly correlated with their decolorization. After the third step, a reduction of 60-80% in color, 50-70% in COD and 60-70% in total phenolics were achieved. Comparative mass and nuclear magnetic resonance spectra indicated increasing degradation of the effluent components after each stage. Toxicity (LC₅₀ values) against Artemia larvae was reduced by two to five folds.     

Toxicities effects of pharmaceutical, olive mill and textile wastewaters before and after degradation by Pseudomonas putida mt-2

Background  

Removal of numerous classes of chemical pollutants from the industrial wastewater such as textile, pharmaceutical and olive mill using conventional wastewater treatment, is incomplete and several studies suggested that improvement of this situation would require the application of biological treatment techniques. Dyes, polyphenols and drugs are an environmental pollutants extremely toxics to plants and other living organisms including humans. These effluents were previously treated by Pseudomonas putida. The main of this work was to evaluate the in vivo toxicity of the three wastewaters.     

Thermo-alkali-stable catalases from newly isolated Bacillus sp. for the treatment and recycling of textile bleaching effluents

Three thermoalkaliphilic bacteria, which were grown at pH 9.3–10 and 60–65 °C were isolated out of a textile wastewater drain. The unknown micro-organisms were identified as thermoalkaliphilic Bacillus sp. Growth conditions were studied and catalase activities and stabilities compared. Catalases from Bacillus SF showed high stabilities at 60 °C and pH 9 (t_1/2=38 h) and thus this strain was chosen for further investigations, such as electron microscopy, immobilization of catalase and hydrogen peroxide degradation studies. Degradation of hydrogen peroxide with an immobilized catalase from Bacillus SF enabled the reuse of the water for the dyeing process. In contrast, application of the free enzyme for treatment of bleaching effluents, caused interaction between the denaturated protein and the dye, resulting in reduced dye uptake, and a higher color difference of 1.3 ΔE* of dyed fabrics compared to 0.9 ΔE* when using the immobilized enzyme.