Assessment of Mycotoxins in Edible Tree Borne Oil Seeds (TBOS)

Assessment of mycoflora and mycotoxins associated with Tree Borne Oil Seeds (TBOS) namely Buchanania lanzan Spreng. (chironji), Juglans regia Linn. (walnut), Prunus armeniaca Linn. (apricot) and Shorea robusta Gaertn. (sal) indicates Aspergillus flavus, A. niger and Penicillium citrinum as the most frequently occurring fungi. Significant variation in pattern of mycoflora incidence was observed in fresh & stored samples. Mycotoxin producing fungi were screened under laboratory conditions for their ability to produce mycotoxins. The percentage toxigenicity was higher in the isolates of A. flavus in comparison to other mycotoxigenic fungi. In B. lanzan, twenty six percent isolates of A. flavus were toxigenic and produced up to 26 µg/ml aflatoxin B1 in the liquid media followed by J. regia (19 µg/ml), P.armeniaca (4µg/ml) and S. robusta 3.5 µg/ml). Stored samples exhibited high concentration of aflatoxin B1 when analysed for natural occurrence of mycotoxins. Level of aflatoxin B1 recorded in P. armeniaca, S. robusta, J. regia and B. lanzan was up to 0.98 µg/g, 0.91 µg/g, 0.54 µg/g and 0.48 µg/g respectively. The level of other mycotoxins citrinin, ochratoxin and zearalenone were comparatively low. Analysis of oil extracted from fungal infected stored samples showed presence of aflatoxins in natural occurrence. Incidence of aflatoxin B1 was higher in apricot oil (up to 0.32 µg/g), up to 0.28 µg/g in chironji and walnut oil whereas in sal butter up to 0.23 µg/g. TBOS under study exhibited significant reduction in the oil seeds under study exhibited oil content during fungal infection, however, reduction was more prominent in case of A. flavus in all cases.