Determination of flavonoid level variation in onion (Allium cepa L.) infected by Fusarium oxysporum using liquid chromatography-tandem mass spectrometry

作者：Lee Jung Han; Lee Soo Jung; Park Semin; Jeong Sung Woo; Kim Chi Yeon; Jin Jong Sung^*; Jeong Euh Duck; Kwak Youn Sig; Kim Soo Taek; Bae Dong Won; Kim Gon Sup; Shin Sung Chul

来源：Food Chemistry, 2012, 133(4): 1653-1657.

DOI：10.1016/j.foodchem.2012.02.063

• Allium cepa L.
• Fusarium basal rot
• Fusarium oxysporum
• Defense materials
• Flavonoid
• HPLC-MS/MS

In order to evaluate the flavonoid level variation in an onion (Allium cepa L) infected by Fusarium oxysporum, the bulbs of a healthy onion and of an infected one were analysed for flavonoids via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). Among eleven flavonoids characterised, isorhamnetin 4%26apos;-O-galactoside (8) was identified in an onion for the first time. When the healthy bulb was inoculated with the fungus, the two quercetin derivatives (4 and 7) and the two isorhamnetin derivatives (Sand 9) underwent concentration changes typical for the defense materials against pathogens. The yellow granules that were accumulated on the abaxial epidermal cell layers after 8 days of inoculation were confirmed as quercetin (10) and isorhamnetin (11). It was deduced that they were produced from flavonoids 4, 5,7 and 9 by hydrolysis enzyme of the fungus.

• 出版日期2012-8-15