Shen P.,Guangxi University of Technology |
Shen P.,State Key Laboratory for Conservation |
Song Z.,Guangxi University of Technology |
Song Z.,State Key Laboratory for Conservation |
And 8 more authors.
Journal of Basic Microbiology
Anisic acid, the precursor of a variety of food flavors and industrial raw materials, can be bioconversed from anethole which extracted from star anise fruits. WGB31 strain with anisic acid molar production rate of 10.25% was isolated and identified as Burkholderia sp. Three significant influential factors, namely, glucose concentration, initial pH value, and medium volume were selected and their effects were evaluated by Box-Behnken Design (BBD). Regression analysis was performed to determine response surface methodology and the significance was tested to obtain the process model of optimal conditions for producing anisic acid. The fermentation conditions at the stable point of the model were obtained: glucose 6gL-1, pH 6.2, culture medium volume 61mL in a triangular flask with 250ml volume. Verification test indicated that the production rate of anisic acid was 30.7%, which was three times of that before optimizing. The results provide a basis and reference for producing anisic acid by microbial transformation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Zhu X.,State Key Laboratory for Conservation |
Zhu X.,Guangxi University |
Quan S.,State Key Laboratory for Conservation |
Quan S.,Guangxi University |
And 9 more authors.
Romanian Biotechnological Letters
A variety of vectors have been developed to deliver DNA into porcine somatic cells, nevertheless, the concerns of bio-safety, operational complexity, high cytotoxicity and low transfection efficiency restrict their widespread applications in genetic modification of porcine somatic cells. Xfect polymer is a novel biodegradable transfection reagent has been employed to deliver exogenous genes into several types of eukaryotic cell with minimal cytotoxicity and superior transfection efficiency. This study was designed to examine whether Xfect polymer is suitable for genetically modifying porcine somatic cells. Transfection conditions including dosage of plasmid DNA and duration of polyplexes incubation were optimized. Then, optimized transfection conditions combining with G418 screening were used to establish Guangxi Bama mini-pig transgenic fibroblast cell lines. Intense expression of red fluorescence protein as a reporter gene in porcine transgenic fibroblasts was detected using a fluorescent microscopy. Furthermore, good cell proliferation and almost no morphological signs of cell stress were also observed. Therefore, our findings suggest Xfect polymer could effectively introduce exogenous genes into porcine somatic cells serves as an alternative transfection method. © 2014 University of Bucharest. Source
Zhang Z.X.,South China Agricultural University |
Zhang Z.X.,State Key Laboratory for Conservation |
Zhou Y.,South China Agricultural University |
Song X.N.,South China Agricultural University |
And 4 more authors.
In this study, the toxicity of whole grass Typha angustifolia L. extract was determined in vitro by a "water tube" method to investigate the bioactivity of T. angustifolia L. against micrergates of red imported fire ants. Results indicated that the ethanol extract exhibited toxicity against the micrergates of red imported fire ants. Mortality was 100% after the micrergates were treated with 2000 mg/mL of ethanol extract for 72 h. After 48 h of treatment, LC50 values of ethanol extract and petroleum ether fraction were 956.85 and 398.73 mg/mL, respectively. After 120 h, LC50 values of the same substances were 271.23 and 152.86 mg/mL, respectively. A bioactivity-guided fractionation and chemical investigation of petroleum ether fraction yielded an active component (compound 1). NMR spectra revealed that the structure of compound 1 corresponded to 3ß-hydroxy-25-methylenecycloartan-24-ol. Compound 1 also exhibited strong toxicity against the micrergates of red imported fire ants, thereby eradicating all of the tested ants treated with 240 mg/mL for 120 h. LC50 values of compound 1 at 48 and 120 h were 316.50 and 28.52 mg/mL, respectively. Source
Zhao Y.,South China Agricultural University |
Fang X.,South China Agricultural University |
Mu Y.,South China Agricultural University |
Cheng Y.,South China Agricultural University |
And 9 more authors.
Bulletin of Environmental Contamination and Toxicology
Crops produced on metal-polluted agricultural soils may lead to chronic toxicity to humans via the food chain. To assess metal pollution in agricultural soils and soybean in southern China, 30 soybean grain samples and 17 soybean-field soil samples were collected from 17 sites in southern China, and metal concentrations of samples were analyzed by graphite furnace atomic absorption spectrophotometer. The integrated pollution index was used to evaluate if the samples were contaminated by Cd, Pb, Zn and As. Results showed that Cd concentration of 12 samples, Pb concentration of 2 samples, Zn concentration of 2 samples, and As concentrations of 2 samples were above the maximum permissible levels in soils. The integrated pollution index indicated that 11 of 17 soil samples were polluted by metals. Metal concentrations in soybean grain samples ranged from 0.11 to 0.91 mg kg;1 for Cd; 0.34 to 2.83 mg kg;1 for Pb; 42 to 88 mg kg;1 for Zn; and 0.26 to 5.07 mg kg;1 for As, which means all 30 soybean grain samples were polluted by Pb, Pb/Cd, Cd/Pb/As or Pb/ As. Taken together, our study provides evidence that metal pollution is an important concern in agricultural soils and soybeans in southern China. © Springer Science+Business Media New York 2014. Source