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Background. Mitochondrial respiratory chain (RC) disorders are a growing group of disorders with a large variety of clinical presentations ranging from well-defined clinical syndromes to nonspecific manifestations, such as failure to thrive, exercise intolerance and seizures.Objective. To describe the clinical, biochemical, and histochemical spectrum of 38 Egyptian patients clinically suspected of havingmitochondrial RC disorders.Methods. A total of 38 patients (female, n=18 (47.4%); male, n=20 (52.6%)) clinically suspected of having mitochondrial diseases had been referred to the Inherited Metabolic Diseases Laboratory at Cairo University Children’s Hospital. Laboratory investigations and analyses included histochemical staining of cytochrome c oxidase and succinate dehydrogenase in muscle biopsies, as well as spectrophotometric assays of RC complexes in muscle homogenates.Results. Twenty-three patients (60.5%) were diagnosed with different RC enzyme deficiencies. Fifteen patients (65%) had complex Ideficiency and all of them also had lactic acidosis (mean (standard deviation)) plasma lactate concentration of 4 (1.65) mmol/L). Twopatients (9%) with marked complex IV deficiency both showed COX-negative ragged red fibers (RRFs) on histochemical staining.Combined complex I and complex II deficiency with scattered COX-stain deficiency and RRFs was diagnosed in 2 patients (5.25%), whilea further 2 patients (5.26%) had combined (complex I, II+III, complex IV) deficiencies. Isolated complex II deficiency was diagnosed in2 patients (5.26%) and 15 (39.5%) patients had normal RC enzyme activities.Conclusion. Biochemical assay of RC complexes is considered the cornerstone for diagnosis of RC complex mitochondrial disorders.These disorders are common among Egyptian paediatric patients.

Anaerobic digestion found limited use in sludges from industrial wastewater treatment plants (WWTPs). So, it is of interest to assess the biodegradability and co-digestion performance of industrial sludges of biological origin alone and when mixed with municipal sludge. In this study, sludge from two different organized industrial districts (OIDs) and textile industry WWTPs are individually mixed with municipal sludge with and without ultrasound pretreatment to investigate their energy production potential and digestibility using biochemical methane potential tests. Sludges were used at different mass ratios in reactors with F/M ratio of 1. During operation, biogas amount and methane percentage were measured. Before and after reactor operation, total solids (TS), volatile solids (VS), chemical oxygen demand (COD) and pH were measured as performance indicators of digestion. Methane production potential was highest in reactors containing only municipal sludge and lowest containing only industrial sludge. The specific methane production normalized with COD removed for OID I, OID II and textile sludges were 0.13 L/g, 0.11 L/g and 0.11 L/g, respectively; whereas average specific methane production for municipal sludge was 0.31 L/g. COD, TS and VS reductions were lower in industrial sludges compared to domestic sludge. The co-digestion reactors with mixed industrial and municipal sludge performed in accordance with the proportion of two sludges. Ultrasonication improved the digestion performance. Although adding industrial sludge reduced the observed biogas amount to lower than that expected, results show that it is possible to co-digest some industrial sludges with municipal sludge in closely coordinated additions (about

The environmental impact of chlorinated pesticides, including endosulfan, is not only caused by their persistency in the ecosystem but also from their toxic effects on off-target living organisms. In this study, three different strains of microorganisms, namely Afipia genosp, Sphingomonas yanoikuyae Q1 and Methylobacterium rhodesianum that are capable of biodegrading endosulfan at low concentrations (100 µg/L) from a tea cultivation field were reported. The isolated microbial consortium biodegraded 59% of the total endosulfan (63% α-endosulfan, 57% β-endosulfan) at pH 6.5. The same consortium biodegraded 98% of the total endosulfan (96% of α-endosulfan, 97% of β-endosulfan) at pH 8.4. All endosulfan removal performances were observed for a period of 25 days and the experiments were conducted at 25 °C, which was a relatively lower temperature compared to other endosulfan biodegradation studies in the literature. Additional carbon source did not change the overall endosulfan removal. No endosulfan sulfate production was observed during the study.

Algal treatment methods have been widely used in nutrient removal studies. However, in most cases, the experimental conditions have not been fully complied with actual conditions. For instance, the effect of algae acclimation to wastewater medium on cell growth and removal efficiency has generally been ignored in laboratory scale experiments. This paper investigates the effect of acclimation on cell growth and nutrient uptake rates of Arthrospira platensis and Chlorella vulgaris. For this purpose, batch reactors, which contained the synthetic secondary effluent, had been inoculated by acclimated algae cells and the growth parameters were measured daily, as well as nutrient concentration. A significant decrease (P < 0.05) in chlorophyll-a content of acclimated A. platensis was observed, although there was no significant change in specific growth rate (μ) and doubling time (dt), in comparison with the non-acclimated ones. Moreover, the acclimation process changed the chlorophyll-a content and kinetic parameters of Chlorella vulgaris. Furthermore, t test results showed a significant increase in removal rate of nitrogen compounds through the acclimation. Residence time of A. platensis and C. vulgaris was also reduced through the acclimation by approximately 50% and 25%, respectively.

The purpose of this study was to observe the effects of different starvation conditions on the surface characteristics and adhesive properties of bacteria. Three pure culture xenobiotic degrading bacteria were used in this study: Pseudomonas sp. strain A, Pseudomonas sp. strain D and Rhodococcus corallinus strain 11. These microorganisms were selected for to their ability to degrade cyanuric acid, which is a derivative of s-Triazine, a common herbicide. These microorganisms were separately starved for carbon (glucose) and nitrogen (cyanuric acid) and their physiological responses to starvation were measured. Results indicated that there was a remarkable shrinkage in size of Pseudomonas strain A starved for carbon for 16 days. The surface properties of these three microorganisms changed significantly on starvation. Surface hydrophobicities for all the microorganisms stayed more or less constant during carbon starvation conditions, whereas, there was a significant decrease in hydrophobicity when all three cultures were starved for nitrogen. In parallel to these findings, it was observed that when the hydrophobicity of the cultures decreased, the attachment capabilities of these microorganisms decreased. This is believed to be due to the production of highly hydrated extracellular polysaccharides when carbon is present in the medium. Results of this study have important implications on the transport and attachment of microorganisms during soil remediation processes.

Resuscitation behavior of bacteria after starvation for carbon and nitrogen was investigated. In addition effect of carbon and nitrogen starvation conditions on the surface characteristics and adhesive properties of bacteria were studied. Two pure culture herbicide degrading bacteria were used in the study: Pseudomonas sp. strain A, and Rhodococcus corallinus strain 11. These bacteria are known to degrade cyanuric acid which is a derivative of s-triazine, a common herbicide used widely. Selected bacteria were starved for carbon (glucose) and nitrogen (cyanuric acid) in different bioreactors and their physiological responses to starvation and resuscitation were measured. Different resuscitation responses were observed under different starvation conditions such that long lag phase was, observed for Rhodococcus corallinus strain 11 subjected to cyanuric acid starvation. Slow exponential growth rates were calculated for both microorganisms subjected to cyanuric acid starvation. The surface properties of both microorganisms were investigated using MATH test with two different hydrocarbons (hexadecane and octane). Hexadecane was observed to be the best organic attachment phase for these tests. Surface hydrophobiciy for all the microorganisms stayed unchanged during carbon starvation conditions. Significant decrease in hydrophobicity was observed for both cultures starved for nitrogen. When the hydrophobicity of the cultures decreased, the attachment capabilities of the microorganisms decreased. The decrease in attachment capabilities is a result of highly hydrated extracellular polysaccharides produced in the presence of carbon in the medium. Results of this study can be used as control tools in soil remediation applications.