title: Enzymes hydrolyzing structural components and ferrous ion cause rusty-root symptom on ginseng (Panax ginseng).
abstract: Microbial induction of rusty-root was proved in this study. The enzymes hydrolyzing plant structural materials, including pectinase, pectolyase, ligninase, and cellulase, caused the rusty-root in ginseng. Pectinase and pectolyase produced the highest rusty-color formation. Ferrous ion (Fe+++) caused the synergistic effect on rusty-root formation in ginseng when it was used with pectinase. The effect of ferric ion (Fe++) on rusty-root formation was slow, compared with Fe+++, probably due to gradual oxidation to Fe+++. Other metal ions including the ferric ion (Fe++) did not affect rusty-root formation. The endophytic bacteria Agrobacterium tumefaciens, Lysobacter gummosus, Pseudomonas veronii, Pseudomonas marginalis, Rhodococcus erythropolis, and Rhodococcus globerulus, and the rotten-root forming phytophathogenic fungus Cylindrocarpon destructans, caused rusty-root. The polyphenol formation (rusty color) was not significantly different between microorganisms. The rotten-root-forming C. destructans produced large quantities of external cellulase activity (about 2.3 U[micronM/min/mg protein]), which indicated the pathogenecity of the fungus, whereas the bacteria produced 0.1-0.7 U. The fungal external pectinase activities (0.05 U) and rusty-root formation activity were similar to those of the bacteria. In this report, we proved that microbial hydrolyzing enzymes caused rusty-root (Hue value 15 degrees) of ginseng, and ferrous ion worsened the symptom.
authors.affiliation: Department of Microbiology and Biotechnology, Daejeon University, Daejeon 300-716, Korea.
authors.forename: Chanyong
authors.initials: C
authors.lastname: Lee
authors.forename: Kwang Yup
authors.initials: KY
authors.lastname: Kim
authors.forename: Jo-Eun
authors.initials: JE
authors.lastname: Lee
authors.forename: Sunghan
authors.initials: S
authors.lastname: Kim
authors.forename: Dongkul
authors.initials: D
authors.lastname: Ryu
authors.forename: Jae-Eul
authors.initials: JE
authors.lastname: Choi
authors.forename: Gilhwan
authors.initials: G
authors.lastname: An
mesh_terms: D001419:Bacteria / Q000145:classification / Q000201:enzymology* / Q000378:metabolism / Q000472:pathogenicity; D002482:Cellulose / Q000378:metabolism; D020536:Enzyme Activators / Q000378:metabolism; D005296:Ferrous Compounds / Q000378:metabolism; D005419:Flavonoids / Q000378:metabolism; D006868:Hydrolysis; D006999:Hypocreales / Q000145:classification / Q000201:enzymology* / Q000378:metabolism / Q000472:pathogenicity; D007477:Ions / Q000378:metabolism; D005894:Panax / Q000382:microbiology*; D010636:Phenols / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology*; D018517:Plant Roots / Q000382:microbiology; D059808:Polyphenols
chemical_list: D020536:Enzyme Activators; D005296:Ferrous Compounds; D005419:Flavonoids; D007477:Ions; D010636:Phenols; D059808:Polyphenols; D002482:Cellulose