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Abstract-Aim: To study the antimicrobial and antioxidant activity of the extracts from Chinese traditional medicine-Agrimonia Pilosa Ledeb. Method: The minimum inhibitory concentration (MIC) value and minimum bactericidal concentration (MBC) value of acetone extracts and methanol extracts from Agrimonia Pilosa Ledeb against bacteria , yeasts and fungi were tested by solid agar dilution method, for...
The plant Macaranga peltata (Euphorbiaceae) leaves and stem bark was tested for its in vitro antioxidant, antimicrobial and cytotoxicity activity using different methods. In vitro anti oxidant activity stem bark extract showed inhibitory concentration 50% (IC50) value of 10.13 than the leaf extract IC50 = 14.85 for DPPH assay. Standard ascorbic acid showed IC50 = 7.28. For ABTS free radical scavenging...
Headspace gas chromatography-mass spectrometry (GC-MS) was used to study the volatile flavor compounds from submerged cultured Ganoderma sinense mycelium. Over twenty-six different volatile flavor compounds from the cultured G. sinense mycelium were detected, and sixteen compounds were identified, which were mainly ketones, alcohols and lactones. Among all the compounds detected in the mycelium, the...
Isolation and identification of key components of the crude de-emulsifier produced by Bacillus mojavensis was studied. Organic solvent precipitation method was used to extract active ingredients from cell free broth. Crude products extracted by different solvent showed diverse de-emulsification activity. 84% and 73% of the de-emulsifier in cell free broth could be extracted successfully by using isopropanol...
In allusion to the shortcoming of the traditional AHP (analytic hierarchy process) method which requires consistency checking and judgment matrix rectifying frequently, an improved AHP that does not need consistency checking is proposed. Based on 4 main performance indexes, i.e. energy utilization, economic performance, reliability and environment impact, and 9 sub-indexes in total, the model of an...
A new direct methanol fuel cell with a zigzag-folded membrane electrode assembly is proposed. The fuel cell can achieve high output voltage through a simple in-series connection. The problem of fuel supply, which causes decreased output voltage, is examined. For the capillary action fuel supply method, a 4 mm thick filter paper was sufficient to supply fuel to the cell for 1 h operation. To curb the...
A pulse charge control system is presented in this paper for use as a new charger system. It is a hybrid system of the direct methanol fuel cell (DMFC) and electric double layer capacitor (EDLC). It is smaller than the maximum output design. A jump up voltage protection method and an energy increase control method are presented for the advanced pulse charge control. The experimental results when using...
The volatile flavor compounds from submerged culture broth of Ganodermasinense were investigated by head-space gas chromatography-mass spectrometry (GC-MS). More than twenty-eight different volatile flavor compounds from the broth were detected, and twenty compounds were identified, which were mainly ketones, alcohols and lactones. Among all the compounds detected in the broth, the compound with...
A high-performance liquid chromatography with electrochemical detection (HPLC-ECD) method was developed to determine the activity of S-catechol-O-methyltransferase (COMT) in rat tissues including the liver, kidney, lung ,spleen and brain. The 3,4-dihydroxybenzoic acid was used as the substrate for S-COMT in rat tissues. After incubated with different tissues, the product 4-hydroxy-3-methoxybenzoic...
An enzyme linked immunosorbent assay based on polyclonal antibodies with enhanced chemiluminescent (ECL) detection for metolcarb in food is developed. Enzyme tracer dilution and concentration of coating antibody were studied. Under the optimum conditions, the IC50 value and ICu value of assay were determined to be 5 ng mL-1 and 0.2 ng mL-1 respectively. Determination of metolcarb in orange juice and...
Young shoots, collected from about 100 trees, were sprayed on 10 mg/L Sumiseven (S3307) and 100 mg/L Gibberellin (GA3) separately., and investigated for their contents of 10-deacetyl Baccatin III (10-DAB), Baccatin III and Paclitaxel (Taxol) at different time in order to get a better understanding of the synthesis mechanism of taxol in vitro. The result shows that S3307 and GA3 change the metabolism...
A strain of denitrifying bacterium DN7, a facultative aerobic bacterim, was isolated from the sea area near the Changhai County of Dalian. Some physiological and biochemical properties were characterized, 16S rDNA gene sequence was amplified by PCR, and its nucleotide sequence was determined. Based on its physiological and biochemical properties, homology and phylogenetic analysis, strain DN7 was...
Studies on the residue of atrazine in the soil have recently aroused great concern. This article studies the methods of determining the residue of atrazine in the soil, and thus helps solve the problems of pesticide residue. Use methanol aqueous solutions (9:1) to extract the atrazine in the soil. Concentrate the methanol, then chloroform extracted. After concentrating to a defined volume, use GC-14C...
This paper studies how chemical modification influences the Saccharomycescerevisiae adsorption on copper ion and the desorption of nitric acid, and carries out infrared spectrum analysis of native, adsorbing and desorbing saccharomyces cerevisiae. Results show that carboxyl and amino group in Saccharomycescerevisiae play an important role in the process of adsorbing Cu(II). The adsorption on Cu(II)...
Solid-phase extraction procedure was successfully used to purify microcystin-LR from cultured cyanobacteria. The method involved collection of cells by flocculation with polyaluminium chloride, extraction of harvested cells by 50% aqueous methanol, clean-up by liquid-liquid extraction with dichloromethane, and purification by solid-phase extraction. More than 8 mg of microcystin-LR with a purity of...
A environmentally friendly and powerful technique was used for determination of parathion in water samples using hollow fiber supported liquid phase microextraction (LPME) followed by high performance liquid chromatography (HPLC). Some effective parameters on extraction, such as extraction solvent, pH of donor phase, extraction time, extraction temperature and stirring speed were investigated. Under...
The present study was to investigate the protective effect of Echinacea, purpurea (E. purpurea) extract, a natural scavenger of peroxynitrite (ONOO-), on the biomolecules injury induced by ONOO- in vitro. The results showed that E. purpurea extract could prevent the ONOO--mediated damage in tyrosine nitration, low density lipoprotein (LDL) oxidation and DNA strand breaks. The ONOO- scavenging ability...
The batch and dynamic adsorption of powdered activated carbon (PAC) as an adsorbent to eliminate the PFOA from the water for reuse has been studied. The first 100 mL influent (0.5 mmol/L) was totally adsorbed (100%) and more than eighty percent adsorption of PFOA was observed in the next 101-230 mL influent. The static adsorption capacity and the breakthrough capacity were 104.6 mg/g and 95.22 mg/g...
The proton conductivity of chemically cross-linked composite membranes consisting of poly(vinyl alcohol) (PVA) and silicotungstic acid (STA) prepared by solution casting as proton-conducting polymer electrolytes was investigated as a function of blending composition, cross-linking density, and temperature. The conductivity mechanism was investigated by using Impedance spectroscopy in the region between...
In this article we study multiple steady states in ternary homogeneous azeotropic distillation. We show that in the case of infinite reflux and an infinite number of trays, multiple steady states exist when the distillate flow varies non-monotonically along the continuation path of the bifurcation diagram with the distillate flow as the bifurcation parameter. We derive a necessary and sufficient condition...
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