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The occurrence of filamentous bacteria was investigated in 15 French pulp and paper activated sludge wastewater treatment plant (WWTP). Large filamentous populations were present in most of the plants. Identification carried out with conventional methods based on morphological features and staining techniques showed that the four main filamentous bacteria encountered in these industrial WWTP and responsible for bulking belong to the genera Thiothrix sp., Type 021N, Haliscomenobacter hydrossis and Type 0092. During two years a specific survey was performed for three of these WWTP showing recurrent bulking phenomena. Data from WWTP performance, chemical data and filaments characterization were compared to correlate the presence of specific filaments with process operating conditions. [ABSTRACT FROM AUTHOR]

Abstract Background We demonstrated that a Chinese herbal formula, which we refer to as RCM-101, developed from a traditional Chinese medicine formula, reduced nasal and non-nasal symptoms of seasonal allergic rhinitis (SAR). The present study in primary and cultured cells was undertaken to investigate the effects of RCM-101 on the production/release of inflammatory mediators known to be involved in SAR. Methods Compound 48/80-induced histamine release was studied in rat peritoneal mast cells. Production of leukotriene B4 induced by the calcium ionophore A23187 was studied in porcine neutrophils using an HPLC assay and lipopolysaccharide-stimulated prostaglandin E2 production was studied in murine macrophage (Raw 264.7) cells by immune-enzyme assay. Expression of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) was determined in Raw 264.7 cells, using western blotting techniques. Results RCM-101 (1–100 μg/mL) produced concentration-dependent inhibition of compound 48/80-induced histamine release from rat peritoneal mast cells and of lipopolysaccharide-stimulated prostaglandin E2 release from Raw 264.7 cells. Over the range 1 – 10 μg/mL, it inhibited A23187-induced leukotriene B4 production in porcine neutrophils. In addition, RCM-101 (100 μg/mL) inhibited the expression of COX-2 protein but did not affect that of COX-1. Conclusion The findings indicate that RCM-101 inhibits the release and/or synthesis of histamine, leukotriene B4 and prostaglandin E2 in cultured cells. These interactions of RCM-101 with multiple inflammatory mediators are likely to be related to its ability to reduce symptoms of allergic rhinitis.

Ninety wood-inhabiting fungi were screened for their ability to degrade and detoxify acetone extractives in Scots pine (Pinus sylvestris L.) sapwood under solid-state fermentation conditions. Fungal degradation of resin acids and long-chain fatty acids was investigated by high pressure liquid chromatography with evaporative light scattering detection (HPLC-ELSD) and the toxicity of the acetone soluble fractionof wood measured by Microtox assay. Discriminant analysis of data showed different patterns of extractive detoxification for white-rot basidiomycetes and sapstain fungi. The major detoxification skills of basidiomycetes appeared to be related to the highest degradation of resin acids, and particularly dehydroabietic acid. Among them, Ischnoderma benzoinum, Stereum sanguinolentum and Trametes versicolor greatlyreduced the sapwood toxicity due to acetone extractives from the EC50 value of 0.08 mg wood ml-1 to levels between 5-10 mg wood ml-1. [ABSTRACT FROM AUTHOR]

The pulp and paper industry is facing more stringent regulations on the quality of effluent discharges to receiving waters, especially for bleached pulp mills. In most cases, these regulations concern mainly AOX concentrations, biotoxicity and COD level in the final discharges. An effective way to improve pollution balance would be to use ozone as an external treatment to meet environmental regulations. The first part of this work has consisted in the identification of the polluting steps in pulp and paper mill processes in terms of toxic effects. After identification, effluents streams that contribute the most to the global pollution of the mill were selected for ozone treatment.For bleaching effluents, the goal was to eliminate acute toxicity and chlorophenolics to increase biodegradability. Depending on the nature of the effluent, complete detoxification and an increase of biodegradability can be obtained with low ozone doses (0.5--1 kg/ADt of pulp). Ozone has also been applied on the final effluent discharges before and after biological treatment. In hardwood and softwood pulp and paper mill final discharges, the residual COD can be eliminated with a catalyzed ozone treatment. This treatment may allow a water qualitysufficient for reutilisation which could lower water consumption of the pulp processes. [ABSTRACT FROM AUTHOR]

Microbiological control programmes at industrial level should aim at reducing both the detrimental effects of microorganisms on the process and the environmental impact associated to the use of biocides as microbiological control products. To achieve this target, new efficient and environmentally friendly products are required. In this paper, 17 non-specific, commercial enzymatic mixtures were tested to assess their efficacy for biofilm prevention and control at laboratory and pilot plant scale. Pectin methylesterase, an enzyme found in the formulation of two of the mixtures tested, was identified as an active compound able to reduce biofilm formation by 71% compared to control tests.

Lipophilic low molar-mass constituents in wood chips for the paper industry result in low quality pulp, pitch deposition, and effluent toxicity. New biotechnological solutions such as fungal pre-treatment of wood chips can reduce pitch problems. This laboratory-scale study focuses on the potential and limitations of a fungal bio-treatment of Norway spruce chips with the white-rot fungus Trametes versicolor. Different fungal treatment conditions were compared. A 4-week fungal treatment reduced the concentration of resin acids and triglycerides by 40% and 100%, respectively, but neither lowered the energy requirements of the TMP process nor significantly affected the morphological fiber characteristics and the physical pulp properties. The pre-treatment led to slightly poorer optical properties. The Trametes versicolor fungal treatment contributed to a less toxic effluent and improved the biodegradability. A treatment of 2-3 weeks appears optimal.

Thirty exopolysaccharides (EPS) produced by bacteria isolated from biofilms or slimelayers from different paper and board mills in Finland, France and Spain were subjected to size exclusion chromatography and sugar compositional analysis. High performance size exclusion chromatography (HPSEC) analysis revealed that some samples were composed of several molecular weight populations. These samples were fractionated by size exclusion chromatography and pooled accordingly. Principal components analysis (PCA) of the sugar compositions of the different pools indicated the presence of glucans and mannans caused by insufficient removal of the carbon or nitrogen source (yeast extract) from the bacteria growth medium leading to an overestimation of the glucose and mannose level in the sample, respectively. From the point of view of slime problems the EPS populations are the most important for multivariate analysis. Four groups of EPSs have been recognized by PCA analysis: a group of EPSs produced by Enterobacter and related genera similar to the regularly reported colanic acid; a group of Methylobacterium EPSs having high galactose and pyruvate levels and two groups that showed less dense clusters produced by Bacillus and related genera, showing high mannose and/or glucose levels and Klebsiella EPSs that showed galactose with rhamnose as major characteristic sugar moieties. Fourier transform infrared spectroscopy (FT-IR) of the same samples followed by discriminant partial least squares regression (DPLS) and linear discriminant analysis (LDA) showed that, when used with a well-defined training set, FT-IR could be used clustering instead of time-consuming sugar composition analysis. The Enterobacter and Methylobacetrium EPS groups could be recognized clearly. However the fact that this could hardly be done for the other two groups in the dataset indicates the importance of a larger and well-defined training or calibration set. The potential to use FT-IR, as a tool for pattern recognition and clustering with respect to EPS structures produced by micro organisms isolated from a paper mill environment is discussed.

The ability of several white-rot fungal strains to remove and detoxify acetone extractives (pitch or resin) in Scots pine sapwood was investigated in stationary laboratory batch assays. Fungal pretreatment provided up to 62% total pitch reduction and significant decreases in pitch toxicity. The best strains were Bjerkandera sp. strain Stereum hirsutum and Trametes versicolor that eliminated over 93% of the problematic triglyceride fraction and 58-87% of other lipophilic extractive classes in only 2 weeks. Fungal removal of the wood extractives was accompanied by a 7.4-16.9-fold decrease in their inhibitory effect, as determined in the Microtox bioassay. Wood pretreatment by Bjerkandera sp. and T. versicolor caused limited losses of woody mass (less than 4% in 4 weeks); whereas S. hirsutum led to somewhat higher mass losses (7% in 4 weeks). These results indicate the potential of white rot fungi to control pitch deposition problems in pulping and to reduce the aquatic toxicity caused by naturally-occurring lipophilic extractives in forest industry effluents.

To improve the preservation of effluent samples, the contribution of refrigeration, freezing, and freeze-drying techniques to maintain the toxic characteristics of the samples was evaluated. To achieve this evaluation one acute test, three long-term toxicity tests, a biochemical test (P450 induction), and a mutagenicity test (Ames test) were used on the same industrial effluent. Refrigeration and freezing demonstrated a similar capacity of preservation. However, freezing should be recommended when the delay between sampling and the start of the bioassay exceeds 48 hr. Freeze-drying did not prove to be useful in that case but this could be due to methodological problems. Nevertheless, this technique allowed the detection of mutagenic compounds because of its aptitude to concentrate effluent samples. For the toxic evaluation of the samples the advantages of the use of a battery of biotests were confirmed and it was noted that the cladoceran (Ceriodaphnia dubia) reproduction test and the algal (Selenastrum capricornutum) growth test had a higher sensitivity within the three tests used.