The polysaccharides in yam bulbils were extracted, and their antioxidant activity and hypoglycemic effect in diabetic mice were discussed. The results showed that the antioxidant activity of polysaccharides in yam bul...The polysaccharides in yam bulbils were extracted, and their antioxidant activity and hypoglycemic effect in diabetic mice were discussed. The results showed that the antioxidant activity of polysaccharides in yam bulbils was signifi- cantly enhanced with the increase of concentration; they showed a strong scaveng- ing ability against DPPH. and .OH, and the scavenging ability was dose dependent to some extent; the scavenging rates reached 91.15% and 89.06% respectively when the dose reached 4.0 mg/ml; the polysaccharides in yam bulbils significantly educed the blood glucose in model rice, and the hypoglycemic effect of large-dose polysaccharides was more obvious. The polysaccharides in yam bulbils has good antioxidant activity and hypoglycemic effect, which provides a new source for devel- opment of safe and natural food antioxidants and blood sugar-lowering agents.展开更多
Residues of 14C--f e.itrothio. in a model rice--fish ecosystem and field rice--fish ecosystem were studied. When equal amounts of the pesticide were applied, the extractable residues in brown rice (equivalent to 34.3f...Residues of 14C--f e.itrothio. in a model rice--fish ecosystem and field rice--fish ecosystem were studied. When equal amounts of the pesticide were applied, the extractable residues in brown rice (equivalent to 34.3f 1.9 μg / kg fenitrothion) and rice stems and leaves (20.9± 1.5 μg / kg) of the model rice-fish ecosystem were 10-15times higher than that of the field rice-fish ecosystem(4.48 ± 0.13 μg / kg and 1.27 ±0.34 μg / kg respectively). Residues in upper part of the soil (6.50± 0.1- 8.10±0.2 μg / kg) and lower part of the soil (1.30± 0.1-1.50±0.1μg / kg) of the model rice-fish ecosystem were 10-40 times higher than that of the field rice-fish ecosystem (0.17 ±0.01 μg / kg). The extractable residues in paddy water of the model ecosystem (0.30 ± 0.01 μg / kg) were similar to that of the field ecosystem (0.20 ± 0.02 μg / kg). Whenthe fenitrothion was sprayed on the rice plants, residues in brown rice, fish body, soiland paddy water were lower than those when the pesticide was sprayed on the surfaceof the soil.展开更多
To detect gatifloxacin （GAT） residue in swine urine, an electrochemical immunoassay was established, An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked...To detect gatifloxacin （GAT） residue in swine urine, an electrochemical immunoassay was established, An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay （ELISA） plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody. Horseradish peroxidase （HRP） conjugated to goat anti-rabbit IgG was used as the enzymatic label. A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator. The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration （IC50） of 8.9 ng/ml was obtained. Excellent specificity of the antibody was achieved with little cross-reaction with Iomefloxacin （3.0%）, ciprofloxacin （3.0%）, and ofloxacin （1.9%） among commonly used （fluoro）quinolones. In conclusion, the im- munoassay system developed in this research can be used as a rapid, powerful and on-site analytical tool to detect GAT residue in foods and food products.展开更多
基金Supported by Key Project of Huainan Normal College(2011LK76zd)Youth Fund of Huainan Normal College(2010LK13)~~
文摘The polysaccharides in yam bulbils were extracted, and their antioxidant activity and hypoglycemic effect in diabetic mice were discussed. The results showed that the antioxidant activity of polysaccharides in yam bulbils was signifi- cantly enhanced with the increase of concentration; they showed a strong scaveng- ing ability against DPPH. and .OH, and the scavenging ability was dose dependent to some extent; the scavenging rates reached 91.15% and 89.06% respectively when the dose reached 4.0 mg/ml; the polysaccharides in yam bulbils significantly educed the blood glucose in model rice, and the hypoglycemic effect of large-dose polysaccharides was more obvious. The polysaccharides in yam bulbils has good antioxidant activity and hypoglycemic effect, which provides a new source for devel- opment of safe and natural food antioxidants and blood sugar-lowering agents.
文摘Residues of 14C--f e.itrothio. in a model rice--fish ecosystem and field rice--fish ecosystem were studied. When equal amounts of the pesticide were applied, the extractable residues in brown rice (equivalent to 34.3f 1.9 μg / kg fenitrothion) and rice stems and leaves (20.9± 1.5 μg / kg) of the model rice-fish ecosystem were 10-15times higher than that of the field rice-fish ecosystem(4.48 ± 0.13 μg / kg and 1.27 ±0.34 μg / kg respectively). Residues in upper part of the soil (6.50± 0.1- 8.10±0.2 μg / kg) and lower part of the soil (1.30± 0.1-1.50±0.1μg / kg) of the model rice-fish ecosystem were 10-40 times higher than that of the field rice-fish ecosystem (0.17 ±0.01 μg / kg). The extractable residues in paddy water of the model ecosystem (0.30 ± 0.01 μg / kg) were similar to that of the field ecosystem (0.20 ± 0.02 μg / kg). Whenthe fenitrothion was sprayed on the rice plants, residues in brown rice, fish body, soiland paddy water were lower than those when the pesticide was sprayed on the surfaceof the soil.
基金supported by the National High-Tech R&D Program(863)of China(Nos.07AA10Z435 and 2007AA06A407)the National Natural Science Foundation of China(No.20675048)+1 种基金the Fundamental Research Funds for the Central Universities(No.65011121)the Shandong Provincial Natural Science Foundation(No.Y2008B31),China
文摘To detect gatifloxacin （GAT） residue in swine urine, an electrochemical immunoassay was established, An indirect competitive immunoassay was developed, in which the coating antigen is immobilized in an enzyme-linked immunosorbent assay （ELISA） plate and GAT residue from the sample competes with the limited binding sites in added anti-GAT antibody. Horseradish peroxidase （HRP） conjugated to goat anti-rabbit IgG was used as the enzymatic label. A carbon fiber working electrode was constructed and current signals were detected by using hydrogen peroxide as a substrate and hydroquinone as an electrochemical mediator. The electrochemical immunoassay was evaluated by analysis of GAT in buffer or swine urine and an average value of half inhibition concentration （IC50） of 8.9 ng/ml was obtained. Excellent specificity of the antibody was achieved with little cross-reaction with Iomefloxacin （3.0%）, ciprofloxacin （3.0%）, and ofloxacin （1.9%） among commonly used （fluoro）quinolones. In conclusion, the im- munoassay system developed in this research can be used as a rapid, powerful and on-site analytical tool to detect GAT residue in foods and food products.
