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Leng F.,Lanzhou University of Technology | Leng F.,The Key Laboratory of Screening | Sun S.,Lanzhou University of Technology | Sun S.,The Key Laboratory of Screening | And 7 more authors.
Tropical Journal of Pharmaceutical Research | Year: 2016

Purpose: To develop a novel biotechnological method for removing toxic arsenic from two kinds of representative arsenic-containing ores using different mixed mesophilic acidophiles. Methods: Bioleaching of the two types of arsenic-containing ores by mixed arsenic-unadapted Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans or mixed arsenic-adapted cultures, were carried out. Arsenic bioleaching ratios in the various leachates were determined and compared. Results: The results showed that the maximum arsenic leaching ratio obtained from realgar in the presence of mixed adapted cultures was 28.6%. However, the maximum arsenic leaching ratio from realgar in the presence of mixed unadapted strains was only 12.4%. Besides, maximum arsenic leaching ratios from arsenic-bearing refractory gold ore by mixed adapted strains or unadapted strains were 45.0 and 22.9%, respectively. Oxidation of these two ores by sulfuric acid was insignificant, as maximum arsenic leaching ratios of realgar and arsenic-bearing refractory gold ore in the absence of any bacterium were only 2.8 and 11.2%, respectively. Conclusion: Arsenic leaching ratio of realgar and refractory gold ore can be enhanced significantly in the presence of arsenic-adapted mesophilic acidophiles. © Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, 300001 Nigeria. All rights reserved. Source

Guo T.,Lanzhou University of Technology | Guo T.,The Key Laboratory of Screening | Qing Wei J.,Lanzhou University of Technology | Qing Wei J.,The Key Laboratory of Screening | And 2 more authors.
Pharmaceutical Biology | Year: 2015

Context The root of Potentilla anserina L. (Rosaceae) is an herbal medicine that has been used as an antitussive and expectorant drug for thousands of years in Chinese folk medicine. Objective: This study estimated the antitussive and expectorant effects of P. anserina extract to validate its traditional use. Materials and methods The antitussive and expectorant activities of the ethanol extract, aqueous extract, and polysaccharides from P. anserina were evaluated using classical animal models. Results The results showed that in three antitussive tests, the aqueous extract and polysaccharides at high and low doses significantly inhibited the frequency of cough induced by ammonia and sulfur dioxide in mice and by citric acid in guinea pigs, and increased the latent period of cough in guinea pigs. Similarly, the aqueous extract and polysaccharides also showed significant expectorant activity compared with the control in phenol red secretion experiments. Polysaccharides at dose of 600 mg/kg enhanced tracheal phenol red output by 121.1%, the ammonium chloride (positive control) at dose of 1000 mg/kg by 117.4%. However, the ethanol extract at a high dose (600 mg/kg) has antitussive activity only in the sulfur dioxide induced coughing test. Moreover, the polysaccharides at the same dose showed better bioactivity than the aqueous extract in all tests. Discussion and conclusion The results of the present study provide evidence that P. anserina can be used as an antitussive and expectorant herbal medicine and that polysaccharides may be the main active ingredients of P. anserina responsible for its bioactivities. © 2015 Taylor & Francis Source

Pu X.,Lanzhou University of Technology | Pu X.,The Key Laboratory of Screening | Ren J.,Lanzhou University of Technology | Ren J.,The Key Laboratory of Screening | And 10 more authors.
International Journal of Clinical and Experimental Medicine | Year: 2015

Objective: In the present study, the antiviral effects of polyphylla saponin I isolated from Parispolyphylla on influenza A virus are investigated both in vitro and in vivo. Methods: Column chromatography and reversed phase liquid chromatography separation technology were used to extract and purify polyphylla saponin I. The purity of polyphylla saponin I was assayed by high performance liquid chromatography. Methyl thiazolyl tetrazolium assay and analyses of cytopathic effects were performed to examine the antiviral activity of polyphylla saponin I upon MDCK cells infected with influenza A virus. Model mice were made by intranasal inoculation of influenza a virus. Mice infected with influenza A virus were orally administered polyphylla saponin I and oseltamivir twice a day for 5 days to study their antiviral efficacy in vivo. Results: Polyphylla saponin I had no cytotoxicity on MDCK cells at the concentration of 50 μg/mL. Polyphylla saponin I (6.25, 12.5, 25 and 50 μg/mL) and oseltamivir (40 μg/mL) had remarkable inactivation effects on influenza A virus, prevention effects on influenza A virus adsorption on MDCK cells, and inhibitory effects on the reproduction of influenza A virus in MDCK cells. In addition, polyphylla saponin I (5 and 10 mg/kg), and oseltamivir (3 mg/kg) significantly reduced viral hemagglutination titer, improved the pathologic histology of lung tissues, and decreased the mortality of mice infected with influenza A virus. Polyphylla saponin I (5 and 10 mg/kg) prolonged the survival time of mice from 8.5±0.3 days to 13.2±0.5 days, with the prolonged life rates being 49.4% and 55.3%, respectively. Conclusion: Polyphylla saponin I has antiviral activity on influenza A virus both in vitro and in vivo. © 2015, E-Century Publishing Corporation. All rights reserved. Source

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