Seroprevalence, Risk Factors, and Genotypes of Toxoplasma gondii in Free-Range Chickens Intended for Human Consumption in China.

Toxoplasma gondii is a protozoan with worldwide distribution that infects birds and mammals, including humans. The consumption of free-range chicken meat is a common practice in many parts of the world. However, little information is available concerning the molecular prevalence and genotypes of T. gondii infection in free-range chickens intended for human consumption in China. In this study, a total of 1360 serum samples were collected from food markets in Hunan province of China for detecting T. gondii antibodies by indirect hemagglutination assay. In addition, 650 brain tissues were also collected to investigate T. gondii DNA by amplification of B1 gene with a seminested polymerase chain reaction (PCR), and the positive DNA samples were typed at 10 genetic markers using multilocus PCR-restriction fragment length polymorphism. Antibodies to T. gondii were detected in 457 of the examined serum samples (33.6%; 95% confidence interval [CI]: 31.1-36.1), and 72 DNA samples (11.1%; 95% CI: 8.6-13.4) were positive for the T. gondii B1 gene. In this study, region and age of free-range chickens were shown to be risk factors for T. gondii infection (p < 0.01). Two genotypes (ToxoDB#9 and ToxoDB#52) were identified from two samples with complete genotyping results. Our study revealed a high prevalence of T. gondii infection in free-range chickens intended for human consumption in Hunan province, suggesting that recommendations to consumers should be made, especially in some regions of China where consumption of undercooked chicken meat is common. This is the first genetic characterization of T. gondii in free-range chickens intended for human consumption in Hunan province, China, and also the first report of genotype ToxoDB#52 in China.

Biochemical analysis and hypoglycemic activity of a polysaccharide isolated from the fruit of Lycium barbarum L.

Purification, characterization and hypoglycemic activities of polysaccharide from Lycium barbarum L. were investigated in this study. A water soluble polysaccharide (LBP) was obtained with ultrafiltration membranes separation, which was further purified by chromatography of DEAE cellulose column and Sephadex G-150 to get LBP3a and LBP3b. The high performance permeation chromatography (HPGPC) analysis showed that the average molecular weight (Mw) of LBP3b was 4.92kDa. Monosaccharide composition analysis revealed that the LBP3b was comprised of mannose, rhamnose, glucose, galactose and xylose with a molar ratio of 5.52:5.11:28.06:1.00:1.70. The preliminary structure features of LBP3b were investigated by UV, FT-IR, NMR and SEM. In vitro cell experiments showed that LBP3b had significantly inhibited the absorption of glucose in a dose-dependent manner. The study showed that LBP3b had potential use as an anti-diabetic agent.