Dae-Yeul Son

Hot water leaves extracts of Zizyphus jujube exert antioxidative effects in vitro and cytotoxicity in human cancer cell lines

Hot water (JLW) and 70% ethanol (JLE) extracts of jujube leaves were investigated for their antioxidant effect, cytotoxicity, and anticancer effects. The measured content of total polyphenolics in JLW and JLE was 200.4 mg·g−1 and 234.6 mg·g−1, respectively. Extracts showed 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of 91.8% (JLW) and 93.8% (JLE) at 1,000 μg·mL−1. A radical scavenging activity of JLW and JLE was higher than that of Vitamin C (89.3%) (at 1,000 μg·mL−1). Results from the analysis of Super oxide dismutase (SOD)-like activity showed 33.9% for JLW and 34.8% for JLE (at 1,000 μg·mL−1). Extracts showed no cytotoxicity in a normal human cell line, HEK293. In human cancer cells JLW extract showed higher antiproliferative activity than JLE extract. Inhibitory effect of JLW for human breast cancer cells (MCF-7), human stomach cancer cells (AGS), human lung cancer cells (A549) and human liver cancer cells (HepG2) growth was 16.9%, 61.3%, 57.7%, and 20.1% respectively, at 1,000 μg−1mL−1. The results of our study suggest the potential use of Zizyphus jujube leaves extracts for use as an excellent antioxidant and antiproliferative substance.

Pollen allergic risk assessment of genetically modified virus resistant pepper and functional Chinese cabbage

Pollen of genetically modified (GM) pepper containing the gene for cucumber mosaic virus (CMV) coat protein (CP) and GM Chinese cabbage with high phenylethylisothiocyanate (PEITC) content was investigated for assessment of allergic risk. Amino acid (AA) sequences of the inserted gene products of GM virus resistant pepper and GM Chinese cabbage with high PEITC content were compared with those of known allergens. No known allergen greater than 35% AA sequence homology, over 80 AA window or more than 8 consecutive identical AA was found. Protein patterns of GM/non-GM pepper and Chinese cabbage pollen extracts in SDS-PAGE analysis showed the same distribution of protein bands among the GM and non-GM pepper or Chinese cabbage, respectively. Sera from pollen allergic patients showed some IgE reactivity via immunoblotting and ELISA; however, no differences were observed between the pollen of GM and non-GM pepper or Chinese cabbage, respectively. Based on these results, we conclude that pollens of the virus resistant GM pepper and GM Chinese cabbage with high PEITC have no differences in their protein composition or allergenicity relative to non-GM pepper and Chinese cabbage.