Characterization of Simultaneous Aerobic Denitrification and Dephosphorization Strain Cupriavidus sp. H29 and Its Application on Cadmium-Removing

Abstract

A cadmium tolerant strain Cupriavidus sp. H29 could be applied on simultaneous removal of nitrate, phosphorus and cadmium. Response surface methodology (RSM) experiments showed that optimal removal ratios of nitrate, phosphate and Cd(II), which reached 98.89%, 75.23% and 85.01%, occurred at Cd(II) initial concentration of 30.00?mg/L, nitrate initial concentration of 55.20?mg/L, phosphate initial concentration of 50.00?mg/L, initial pH of 7.0 and C/N ratio of 6.0. Studies on gaseous product, precipitations and extracellular polymeric substances (EPS) indicated that the removal of Cd(II) occurred in the extracellular place. Through the coordinated complexation of EPS, strain H29 can achieve the bio-induced phosphate-cadmium removal. Moreover, studies on heated cells, resting cells, permeable cells, cells membrane and cytoplasm demonstrated that the removal of Cd(II) mainly taken place on the cells membrane. This study provided the theoretical basis for the subsequent research of synchronous removal of heavy metals and other pollutants.     

Enhancing rice callus regeneration by extracellular products of Tolypothrix tenuis (Cyanobacteria)

Cyanobacteria produce a wide array of substances with activity in many biological systems. The aim of the present research was to compare the effect of differently treated extracellular products (EP) from Tolypothrix tenuis (Cyanobacteria) on rice plantlet regeneration as well as on the pigments, protein, total free porphyrin contents, and 5-aminolevulinate dehydratase (ALA-D) activity in rice callus during differentiation. Rice embryo calli were regenerated in Murashige & Skoog medium supplemented with EP with protein (EPp) or without protein (EPnp) or autoclaved (EPa), as well as with benzyladenine (BA) and benzyladenine + naphthaleneacetic acid (BA + NAA). At day 75, calli percentage regeneration were: EPnp (84%), EPp (58%), BA + NAA (45%), BA (44%), EPa (40%). The same trend was found for chlorophyll a, b, total and carotenoid contents. Protein content in BA, BA + NAA and EPnp treatments was 35% higher than in EPp and EPa. Total free porphyrin was similar in all treatments. ALA-D activity in BA, EPp and EPa treatments was 28% higher than in BA + NAA and EPnp. The extracellular bioactive substance(s) from T. tenuis would contain a mixture of thermolabile plant growth regulators that replaced and improved the effects of synthetic plant growth regulators on rice callus organogenesis. Calli were rhizogenic in all the regeneration media tested. The pigment content of the calli was related to percentage regeneration but not to the total free porphyrin and ALA-D activity.     

Lignite Biosolubilization by Bacillus sp. RKB 2 and Characterization of its Products

Abstract

Nowadays, the advancements of coal microbiology and biotechnology have been highly emphasized, providing leading-edge approaches in sustainable development of agriculture and the protection of the environment. The biosolubilization of low-rank coals, such as lignite and leonardite is a promising technology for converting these sedimentary rocks into valuable products. In this study, the process involved in lignite biosolubilization by Bacillus sp. RKB 2 was investigated. The biotransformed lignite and the produced humic substances were determined in vitro in a liquid medium and on a solid matrix. The bacterial strain was isolated from untreated Kazakhstani lignite and was shown to be capable of effectively solubilizing and transforming lignite (5% w/v). Fourier Transform Infrared (FTIR) and UHPLC-QqQ-MS/MS analyses were performed to examine the solubilization products and lignite humic substances processed by bacteria. The absorption peaks of FTIR showed the diverse nature of the bacteria-induced humic substances, and the vast majority of intense peaks detected are mainly below an m/z of 1000?Da (liquid chromatography-mass spectrometry [LC-MS] (QqQ)). Data analysis concluded that our isolate could depolymerize lignite and form bio-humic substances. Due to its ability to solubilize lignite Bacillus sp. RKB 2 may be useful in the coal-bed for in situ bioutilization of low-rank coal.     

Assessment of heavy metal toxicity related with human health risk in the surface water of an industrialized area by a novel technique

This study innovates an assessment technique to evaluate heavy metal toxic load (HMTL). Assessment of surface water in Durgapur industrial area, West Bengal India illustrates that heavy metals in majority of sampling locations exceed the drinking water quality standards. Therefore, pollution status and health impact were predicted by heavy metal pollution index (HPI) and hazard index (HI). More than 50% of sampling locations were marked as polluted. Moreover, 5% and 90% of sampling locations near the industries have health risk to adult and child on ingestion. The study of specific exposure-time and exposure-duration affirms the suitability of water for fishing and regular activities. However, HPI or HI does not quantify heavy metal concentrations that pose threat to human health. Therefore, the proposed assessment technique, HMTL, determines the concentration of heavy metals responsible for health hazard. HMTL identifies Mn, Pb, and Co as toxic metals and estimates 85%, 63%, and 70% removal of these metals from surface water to limit pollution. Origins of metals were also investigated through statistical techniques, which revealed that Fe has geogenic and anthropogenic source, while other metals originate by anthropogenic activities solely. This study demonstrates that HMTL will help the planning authority to document effective water quality management plan.     

Superoxide dismutase, glutathione peroxidase, and glutathione reductase in sheep organs

The enzyme activities of the superoxide dismutase (SOD), glutathione peroxidase (GSHPx), glutathione reductase (GR) and thiobarbituric acid reactive substances (TBARS) content were measured in tissue extracts of the liver, kidney and lung of sheep in a nonpolluted control area (C), a polluted area pasture (PP) and those from polluted areas but fed in the laboratory with an experimental emission supplement diet (EEF). Compared with the control SOD, activity was significantly increased (1.75 times) only in the liver of the PP group. In the EEF group there was a tendency toward lower activities in all organs. The Cu,Zn-SOD isoenzymes pattern analyzed by isoelectrofocusing was different in the organs of the animals exposed to pollutants when compared with those of the controls. In the liver, two new isoenzymes with pI 5.30 and 5.70 were found in the PP group and an additional isoenzyme with pI 5.10 in the EEF group. The kidney isoenzymes with pl 5.30 and 5.40 were inhibited in the EEF group. In the lung, two new isoenzymes appeared with pl 5.30 and 5.40 in the PP group and two new isoenzymes with pI 6.10 and 6.50 in the EEF group. GSHPx activity was inhibited in the liver and kidney of the sheep exposed to pollutants. GR activity was significantly changed only in the liver. The activity in the PP group was 2.30 and 2.10 times higher than in the C and EEF groups, respectively. TBARS content was increased in the liver and kidney of the EEF group compared with the control.     

Biochemical properties of vascular endothelial cells

Present knowledge in the field of vascular endothelial cells is reviewed. The role of endothelial cells in the synthesis of matrix proteins and glycosaminoglycans is described. Endothelial cells play a considerable role in the processes of coagulation and fibrinolysis. They also interact with neurotransmitters and vasomotoric substances, and participate in inflammation and immunological responses. They procuce several different growth factors. Their role in lipoprotein metabolism is of special importance to research into atherosclerosis.     

Male accessory gland substances and the control of sexual receptivity in female Culex tarsalis

ABSTRACT. Homogenates of accessory glands from male Culex tarsalis Coquillet (Diptera; Culicidae) were fractionated using gel filtration column chromatography. A component of low molecular weight capable of suppressing female sexual receptivity was obtained and partially characterized. Proteins present in homogenates of isolated accessory glands formed aggregates with other proteins in extracts of whole mosquitoes. Consequently, previous reports of the molecular weight of biologically active components in homogenates from accessory glands from other mosquito species may be inaccurate.
When female Cx. tarsalis were mated with ³H-leucine labelled males. radioactivity could be found throughout the body of the female 24 h after mating. Autoradiography showed that the radioactivity was incorporated into the cells of various organs, and was not specifically localized in a particular target tissue. Approximately 30% of the total radioactivity transferred to the female was found in the head and thoracic regions, and proteins from the head had a specific activity twice that of the thoracic proteins. Bioassay of isolated body parts from mated and virgin females showed that injections of head tissues from mated females into virgin females suppressed sexual receptivity. These results suggest that the head is involved in the physiological mechanisms resulting in refractory mating behaviour.     

Präformierte chemische Abwehrstoffe in Pflanzen

Es gibt eine Reihe interessanter Ansätze über die mögliche Rolle präformierter chemischer Abwehrstoffe in Pflanzen. Eine abschließende Beurteilung der Rolle solcher Verbindungen bei der Resistenz gegenüber phytopathogenen Krankheitserregern ist im Augenblick aber noch nicht möglich. Die bisher erzielten Ergebnisse sollten jedoch zu weiterer Forschung ermutigen, um noch vorhandene Lücken zu schließen. Besonders dringlich wären Untersuchungen an Wirt-Parasit-Systemen, bei denen neben präformierten chemischen Abwehrstoffen auch gleichzeitig postinfektionell gebildete Verbindungen eine Rolle spielen könnten. Es ist zu erwarten, daß in vielen Fällen beide Abwehrsysteme — und vielleicht noch andere — erst in ihrem Zusammenwirken die Resistenzausprägung bewirken.     

Trace metals in Swedish natural fresh waters

Water samples were collected from unpolluted waters in southern and northern Sweden to show the range of natural trace metal concentrations. The results do not indicate any significant differences in metal levels between the two study areas. Negative correlations with pH exist for total concentrations of Cd, Pb, Al, Mn and Zn. The dissolved (dialysable) metal fractions also increase with increasing acidity. The concentration of humic substances influences the distribution of Fe, Mn, Al, Pb, Cr, Co and As, as shown by positive correlations with water colour.Increasing alkalinity has a limiting effect upon concentrations and annual fluctuations of Cd and Pb, and to some extent on Zn, in running waters.