Application of gamma irradiation in ginseng for both photodegradation of pesticide pentachloronitrobenzene and microbial decontamination.
This study investigates the feasibility of using gamma irradiation for photodegradation of a common residual fungicide, pentachloronitrobenzene (PCNB), in ginseng, and for microbial decontamination. American ginseng, Panax quinquefolius, was subjected to gamma irradiation. PCNB residues were analyzed by gas chromatography with electron capture detection and mass spectrometry. Eighty percent of PCNB (100 ppm) in a methanol aqueous solution was degraded by 5 kGy irradiation, and the primary degradation product was pentachloroaniline. Furthermore, contaminated PCNB (3.7 ppm) in ginseng were reduced to 0.2 ppm after 20 kGy irradiation. The IC(50) for treatment of Sclerotium rolfsii with 20 kGy irradiated PCNB was about 2.7 times higher than that for treatment with unirradiated PCNB. The survival rate of mouse fibroblast L929 cells treated with 20 kGy irradiated PCNB was about 12.9% higher than that of L929 cells treated with unirradiated PCNB. Additionally, after 20 kGy irradiation, less than 5% reduction of contents of ginsenoside Rb1 and Re were observed, and amounts of ginsenosides Rc, Rd, and Rg1 were not reduced significantly. The minimal gamma dose for microbial decontamination was 10 kGy. Therefore, gamma irradiation can be used for both PCNB photodegradation and microbial decontamination of ginseng without obvious loses of ginsenoside contents.
Wen
Hsiao-Wei
HW
Department of Food Science and Biotechnology, National Chung Hsing University, 250, Kuo Kuang Road, Taichung 402, Taiwan, ROC.
Hsieh
Ming-Fa
MF
Wang
Ya-Ting
YT
Chung
Hsiao-Ping
HP
Hsieh
Po-Chow
PC
Lin
I-Hsin
IH
Chou
Fong-In
FI
D000814:Aniline Compounds / Q000032:analysis; D000818:Animals; D001419:Bacteria / Q000528:radiation effects*; D002460:Cell Line; D005240:Feasibility Studies; D005347:Fibroblasts / Q000187:drug effects; D005659:Fungicides, Industrial / Q000528:radiation effects; D005720:Gamma Rays; D013058:Mass Spectrometry; D051379:Mice; D009578:Nitrobenzenes / Q000528:radiation effects*; D005894:Panax / Q000737:chemistry / Q000382:microbiology / Q000528:radiation effects*; D010782:Photolysis
D000814:Aniline Compounds; D005659:Fungicides, Industrial; D009578:Nitrobenzenes; C005805:quintozene; C027673:2,3,4,5,6-pentachloroaniline