Effect of rapeseed peptide on DNA damage and apoptosis in Hela cells.

Rapeseed peptide (RSP), obtained by hydrolyzing rapeseed protein, has anticancer activity. In this study, the effects of RSP on proliferation rate, morphological changes, DNA damage, cell cycle distribution and apoptosis in human cervical carcinoma (Hela) cells were investigated. RSP treatment at a concentration of 640 mg/L for 4 days inhibited Hela cell proliferation significantly, as determined by the MTT assay. We observed a dose-dependent increase in cytotoxicity induced by RSP at 20-640 mg/L. After 4 days of 320 mg/L RSP treatment, typical apoptotic changes were observed by transmission electron microscopy (TEM). Using the comet assay, we found dramatic comet tails, indicating DNA damage by RSP (20-640 mg/L). Moreover, RSP treatment caused inhibition of Hela cell growth, with cycle arrest in the S phase and apoptosis induction. Taken together, the results suggested that rapeseed peptide could be a potential antitumor compound with an apoptotic mode of action.

[Determination of lead in microemulsified rapeseed oil and bio-diesel oil by GFAAS].

Bio-diesel oil has attracted much attention as a substitutable energy sources for its renewable and eco-friendly property. However, problems of lead contamination in fuel are also emphasized increasingly at present. So it was of quite significance to determine the contents of lead in bio-diesel oil and its raw material rapeseed oil. An effective method was developed for the rapid determination of lead in rapeseed oil and bio-diesel oil by graphite furnace atomic absorption spectrometry (GFAAS) after their stabilization as microemulsions. In this research work, polyethyleneglycol octyl phenyl ether and n-butanol were used for emulsifier and auxiliary emulsifying agent, respectively. For Pb, efficient thermal stabilization was obtained using NH4H2PO4 as matrix modifier. Sample stabilization was necessary because of evident analyte losses that occurred immediately after sampling. Excellent long-term sample stabilization and the influence of the microemulsion composition on the GFAAS response were observed by mixing different organic solvents. The ashing and atomization temperature and ramp rate influenced the sensitivity obtained for Ph. Take this into account, the optimum conditions of the graphite furnace atomic absorption spectrometric determination of Pb in rapeseed oil and bio-diesel oil samples were investigated. The results showed that the microemulsion was quite stable when the value of V(20% polyethyleneglycol octyl phenyl ether), V(n-butanol), V(oil) and V(water) was 0.1: 8.9: 0.5: 0.5, without matrix interference effect. The determination limit of the proposed method was 126.2 microg x L(-1) for Pb, comfortably below the values found in the analyzed samples. The recoveries were from 81.8% to 109.0%, which performed using the addition of different concentrations of lead to bio-diesel oil, rapeseed oil and petrochemical diesel samples. The relative standard deviation of determination was 5.84%. This work showed the great efficiency of the microemulsion, indicating that it is possible to extract lead from the oil phase. The method was applied to the determination of lead in oil samples with satisfactory results.

Characterization and antitumor activity of pollen polysaccharide.

The polysaccharide LBPP was extracted and isolated from the pollen of brassica napus L., and the antitumor activity was evaluated on Sarcoma 180-bearing mice and B16 melanoma-bearing mice through transplantable animal tumor. Mice were treated with three doses of the polysaccharide LBPP (50, 100 and 200 mg/kg body weight) for 10 days. Tumor weight, relative spleen and thymus weight, lymphocyte proliferation, natural killer cell activity, delayed type hypersensitivity (DTH), phagocytic function of monocyte, serum hemolysis antibody and peripheral blood of tumor-bearing mice were studied. At the doses of 100 and 200 mg/kg, a significant decrease (P<0.01) in tumor formation, a significant increase (P<0.05) in relative spleen and thymus weight, natural killer cell activity, phagocytic function of monocyte, lymphocyte proliferation, and serum hemolysis antibody, and a significant improvement of peripheral blood abnormality (P<0.05) and anemia (P<0.01) were observed. Results of these studies demonstrated that the polysaccharide LBPP had anti-tumor activity, which was mediated by immunomodulation and leukogenic and antianemic actions.

Characterization and anti-tumor activity of pollen polysaccharide.

The polysaccharide LBPP was extracted and isolated from the pollen of Brassica napus L., and the anti-tumor activity was evaluated on Sarcoma 180-bearing mice and B16 melanoma-bearing mice through transplantable animal tumor. Mice were treated with three doses of the polysaccharide LBPP (50, 100 and 200 mg/kg body weight) for 10 days. Tumor weight, relative spleen and thymus weight, lymphocyte proliferation, natural killer cell activity, delayed type hypersensitivity (DTH), phagocytic function of monocyte, serum hemolysis antibody and peripheral blood of tumor-bearing mice were studied. At the doses of 100 and 200 mg/kg, a significant decrease (P<0.01) in tumor formation, a significant increase (P<0.05) in relative spleen and thymus weight, natural killer cell activity, phagocytic function of monocyte, lymphocyte proliferation, and serum hemolysis antibody, and a significant improvement of peripheral blood abnormality (P<0.05) and anemia (P<0.01) were observed. Results of these studies demonstrated that the polysaccharide LBPP had anti-tumor activity, which was mediated by immunomodulation and leukogenic and antianemic actions.

[Anti-tumor effect of polysaccharide from Grifola frondosa and its influence on immunological function].

When the polysaccharide from Grifola frondosa (PGF) was taken orally by S180 bearing mice at the dosage of 50-150 mg/kg.d for 9 d, the inhibitory rate to S180 was 27.97%-38.46%. The PGF can also enhance thymus index, the ability of splenic lymphocyte proliferation and formation of antibody in splenic cells, and promote the production of IgM hemolysin significantly in S-180 bearing mice.