MYCOFLORA AND MYCOTOXINS IN ADZUKI AND MUNG BEANS PRODUCED IN ONTARIO, CANADA

This is the first report on the detection of fumonisin B-1 (FB1) in Fu sarium-infected adzuki bean (Phaseolus angularis) and mung bean (Phase olus aureus). The infected beans had either a mouldy appearance or a d istinct discoloration. Seed coats of infected adzuki beans changed fro m dark red to light red and those of mung beans from green to dark or brownish green. Fusarium spp. isolated from mouldy and discoloured bea ns included F. avenaceum, F. culmorum, F. equiseti, F. graminearum, F. moniliforme, F. oxysporum, F. solani, F. sporotrichoides and a few un identified species. Healthy beans without any apparent discoloration a nd diseased beans with discoloration and mouldy appearance were analys ed for mycotoxins. Diacetoxyscripenol, deoxynivalenol and T-2 toxin (T -2) were not detected in either healthy or discoloured adzuki and mung bean samples by thin layer chromatography (TLC). FB1 was detected by TLC in discoloured adzuki and mung bean samples but not in the healthy samples. TLC results were confirmed by high performance liquid chroma tography (HPLC). The quantification of FB1 by HPLC revealed that disco loured adzuki and mung bean samples contained 261 +/- 43.8, and 230 +/ - 21.6 mu g g(-1) of FB1, respectively. This investigation emphazises the need for more detailed research in dealing with possible mycotoxin contamination in various foodstuffs including legumes.