Dyes in wastewater are of particular environmental concern since they give an undesirable color to the waters, dye and their derivatives are harmful to human health and the environment ( Annadurai et al., 2002). Due...Dyes in wastewater are of particular environmental concern since they give an undesirable color to the waters, dye and their derivatives are harmful to human health and the environment ( Annadurai et al., 2002). Due to their biological persistency, conventional biological treat-ment processes such as activated sludge process are ineffective for their removal(Shaul et al., 1991). There is a need to develop effective methods for the degradation of such persistent organic pollutants, either to less harmful compounds or, more desirable, to their complete mineralization.展开更多
In recent years, the ability of microorganisms to decolorize textile wastewater has received great attention due to the environmental persistence and toxicity of these pollutants. In this paper biological decolorizati...In recent years, the ability of microorganisms to decolorize textile wastewater has received great attention due to the environmental persistence and toxicity of these pollutants. In this paper biological decolorization of triphenylmethane dye, C.I. Basic Green 4 (BG 4), by Chlorella species was investigated. The effect of operational parameters (temperature, pH, initial dye concentration and algal concentration) on decolorization efficiency was examined. Results indicated that the desired initial pH was 9. The stability and efficiency of the algae in long-term repetitive operations were also examined. Michaelis–Menten kinetics was employed to describe the apparent correlation between the decolorization rate and dye concentration. The optimal kinetic parameters, νmax (specific decolorization rate) and Km (maximum specific decolorization rate) were 4.6 mg dye g cell-1 h-1 and 151.0 mg L-1, respectively.展开更多
In this study, bay laurel extract (BLE) used as a reducing and capping agent for the synthesis of silver nanoparticles (AgNPs). The green-prepared AgNPs investigated using UV-visible spectroscopy, Fourier-transform in...In this study, bay laurel extract (BLE) used as a reducing and capping agent for the synthesis of silver nanoparticles (AgNPs). The green-prepared AgNPs investigated using UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX) and Transmission electron microscopy (TEM). Formation of AgNPs monitored at ambient temperature by a change in color from the starting solution to dark brown. Green synthesis AgNps were investigated for antimicrobial activity. The microorganisms employed were E. coli, K. pneumoniae, B. cereus, S. aureus, C. lbicans and Aspergillus. The susceptibility of microorganisms against the six AgNPs solutions was determined using the disk diffusion method. The catalytic activity of the prepared AgNPs (sample, d) for basic brown 1 dye was investigated. The results showed the characteristic surface plasmon resonance peak of the AgNPs appeared at approximately 415 - 440 nm. XRD revealed peaks at 38.2, 44.16, 64.24 and 77.22 Ɵ, and the intensity of these peaks enhanced when using microwave curing compared to ambient temperature. SEM and TEM results showed that the silver nano particles have a spherical shape and the particle size for samples is less than 34 nm. FTIR spectroscopy measurements showed the binding of organic compounds on the surface of the silver nanoparticles. Highest antibacterial activity was enhanced with increasing of AgNPs dose and with increasing of extract ration against most of microorganisms except. Removal of basic brown 1 dye by the prepared AgNPs indicated complete dye removal after 8 h.展开更多
Kisspeptin is essential for activation of the hypothalamo-pituitary-gonadal axis. In this study, we established gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats. Rats were injected wit...Kisspeptin is essential for activation of the hypothalamo-pituitary-gonadal axis. In this study, we established gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats. Rats were injected with 1, 10, or 100 pM kisspeptin-10, a peptide derived from full-length kisspeptin, into the arcuate nucleus and medial preoptic area, and with the kJsspeptJn antagonist peptJde 234 into the lateral cerebral ventricle. The results of immunohistochemical staining revealed that pulsatile luteinizing hormone secretion was suppressed after injection of antagonist peptide 234 into the lateral cerebral ventricle, and a significant increase in luteinizing hormone level was observed after kisspeptin-10 injection into the arcuate nucleus and medial preoptic area. The results of an enzyme-linked immunosorbent assay showed that luteinizing hormone levels during the first hour of kisspeptin-10 infusion into the arcuate nucleus were significantly greater in the 100 pM kisspeptin-10 group than in the 10 pM kisspeptin-10 group. These findings indicate that kisspeptin directly promotes gonadotropin-releasing hormone secretion and luteinizing hormone release in gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats. The arcuate nucleus is a key component of the kisspeptin-G protein-coupled receptor 54 signaling pathway underlying regulating luteinizing hormone pulse secretion.展开更多
文摘Dyes in wastewater are of particular environmental concern since they give an undesirable color to the waters, dye and their derivatives are harmful to human health and the environment ( Annadurai et al., 2002). Due to their biological persistency, conventional biological treat-ment processes such as activated sludge process are ineffective for their removal(Shaul et al., 1991). There is a need to develop effective methods for the degradation of such persistent organic pollutants, either to less harmful compounds or, more desirable, to their complete mineralization.
基金Financially supported by the University of Tabriz, Iran
文摘In recent years, the ability of microorganisms to decolorize textile wastewater has received great attention due to the environmental persistence and toxicity of these pollutants. In this paper biological decolorization of triphenylmethane dye, C.I. Basic Green 4 (BG 4), by Chlorella species was investigated. The effect of operational parameters (temperature, pH, initial dye concentration and algal concentration) on decolorization efficiency was examined. Results indicated that the desired initial pH was 9. The stability and efficiency of the algae in long-term repetitive operations were also examined. Michaelis–Menten kinetics was employed to describe the apparent correlation between the decolorization rate and dye concentration. The optimal kinetic parameters, νmax (specific decolorization rate) and Km (maximum specific decolorization rate) were 4.6 mg dye g cell-1 h-1 and 151.0 mg L-1, respectively.
文摘In this study, bay laurel extract (BLE) used as a reducing and capping agent for the synthesis of silver nanoparticles (AgNPs). The green-prepared AgNPs investigated using UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Scanning Electron Microscopy with Energy Dispersive X-ray (SEM-EDX) and Transmission electron microscopy (TEM). Formation of AgNPs monitored at ambient temperature by a change in color from the starting solution to dark brown. Green synthesis AgNps were investigated for antimicrobial activity. The microorganisms employed were E. coli, K. pneumoniae, B. cereus, S. aureus, C. lbicans and Aspergillus. The susceptibility of microorganisms against the six AgNPs solutions was determined using the disk diffusion method. The catalytic activity of the prepared AgNPs (sample, d) for basic brown 1 dye was investigated. The results showed the characteristic surface plasmon resonance peak of the AgNPs appeared at approximately 415 - 440 nm. XRD revealed peaks at 38.2, 44.16, 64.24 and 77.22 Ɵ, and the intensity of these peaks enhanced when using microwave curing compared to ambient temperature. SEM and TEM results showed that the silver nano particles have a spherical shape and the particle size for samples is less than 34 nm. FTIR spectroscopy measurements showed the binding of organic compounds on the surface of the silver nanoparticles. Highest antibacterial activity was enhanced with increasing of AgNPs dose and with increasing of extract ration against most of microorganisms except. Removal of basic brown 1 dye by the prepared AgNPs indicated complete dye removal after 8 h.
文摘Kisspeptin is essential for activation of the hypothalamo-pituitary-gonadal axis. In this study, we established gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats. Rats were injected with 1, 10, or 100 pM kisspeptin-10, a peptide derived from full-length kisspeptin, into the arcuate nucleus and medial preoptic area, and with the kJsspeptJn antagonist peptJde 234 into the lateral cerebral ventricle. The results of immunohistochemical staining revealed that pulsatile luteinizing hormone secretion was suppressed after injection of antagonist peptide 234 into the lateral cerebral ventricle, and a significant increase in luteinizing hormone level was observed after kisspeptin-10 injection into the arcuate nucleus and medial preoptic area. The results of an enzyme-linked immunosorbent assay showed that luteinizing hormone levels during the first hour of kisspeptin-10 infusion into the arcuate nucleus were significantly greater in the 100 pM kisspeptin-10 group than in the 10 pM kisspeptin-10 group. These findings indicate that kisspeptin directly promotes gonadotropin-releasing hormone secretion and luteinizing hormone release in gonadotropin-releasing hormone/enhanced green fluorescent protein transgenic rats. The arcuate nucleus is a key component of the kisspeptin-G protein-coupled receptor 54 signaling pathway underlying regulating luteinizing hormone pulse secretion.