title: Variation in flavonoid levels in Citrus benikoji Hort. ex. Tan. infected by Colletotrichum gloeosporioides.
abstract: Anthracnose caused by Colletotrichum gloeosporioides is one of the most serious postharvest diseases of citrus fruit. Fruit peels infected with C. gloeosporioides and the peels of healthy fruit were analysed for flavonoids, using high performance liquid chromatography-tandem mass spectroscopy, to evaluate variations in flavonoid levels in Citrus benikoji Hort. ex. Tan. Seventeen flavonoids were characterised from the fruit peels. The flavonoids were validated using structurally related standards and quantified. Among the 17 flavonoids, the concentration of component 3 was the highest and that of component 10 was the lowest. During 8 days after inoculation, the concentration of the seven flavonoids 1-3, 5, 6, 13, and 14 increased gradually up to day 8. Flavonoid 4 was detected from day 7. The seven minor flavonoid components, 8-12, 15, and 16 increased to day 5 and then decreased. However, flavonoids level variations were not significantly different from that of the non-infected fruits during the experimental period. The monitoring suggested that the constitutively formed seven polymethoxyflavones (8-12, 15, and 16) may act as phytoanticipins in the defence mechanism against the fungus, and that hespertin 7-O-glucoside (4), produced de novo on day 6 after infection, may function as a phytoalexin.
authors.affiliation: Department of Chemistry and Research Institute of Life Science, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Sung Woo
authors.initials: SW
authors.lastname: Jeong
authors.forename: Hae Gyeong
authors.initials: HG
authors.lastname: Kim
authors.forename: Semin
authors.initials: S
authors.lastname: Park
authors.forename: Jung Han
authors.initials: JH
authors.lastname: Lee
authors.forename: Yun-Hi
authors.initials: YH
authors.lastname: Kim
authors.forename: Gon-Sup
authors.initials: GS
authors.lastname: Kim
authors.forename: Jong Sung
authors.initials: JS
authors.lastname: Jin
authors.forename: Youn-Sig
authors.initials: YS
authors.lastname: Kwak
authors.forename: Moo Ryong
authors.initials: MR
authors.lastname: Huh
authors.forename: Ji Eun
authors.initials: JE
authors.lastname: Lee
authors.forename: Yi
authors.initials: Y
authors.lastname: Song
authors.forename: Sung Chul
authors.initials: SC
authors.lastname: Shin
mesh_terms: D002957:Citrus / Q000737:chemistry* / Q000378:metabolism / Q000382:microbiology; D020231:Colletotrichum / Q000502:physiology*; D005419:Flavonoids / Q000032:analysis* / Q000378:metabolism; D005638:Fruit / Q000737:chemistry* / Q000378:metabolism / Q000382:microbiology; D010935:Plant Diseases / Q000382:microbiology*; D010936:Plant Extracts / Q000032:analysis* / Q000378:metabolism
chemical_list: D005419:Flavonoids; D010936:Plant Extracts
keywords: Citrus benikoji; Colletotrichum gloeosporioides; Defence materials; Flavonoids; HPLC–MS/MS