Impact of essential oils on growth rate, zearalenone and deoxynivalenol production by Fusarium graminearum under different temperature and water activity conditions in maize grain.
OBJECTIVE
The effect of five essential oils (oregano, cinnamon, lemongrass, clove and palmarose) on growth rate, zearalenone (ZEA) and deoxynivalenol (DON) production by Fusarium graminearum strains was assessed.


RESULTS
The influence of the essential oils was tested on irradiated maize at two concentrations (500 and 1000 mg kg-1), at different water activity (aw) (0.95 and 0.995) and temperature (20 and 30 degrees C) levels. At 0.995 aw all essential oils tested had an inhibitory effect on growth rate of F. graminearum at both temperatures studied. At this aw level, DON production in general was inhibited by all essential oils at 30 degrees C and, although palmarose and clove were the only essential oils with statistically significant inhibitory effect on ZEA production, an inhibitory trend was observed when cinnamon and oregano oils were added to maize grain.


CONCLUSIONS
Antifungal and antimycotoxigenic activity of the essential oils assayed was shown to depend on environmental conditions.


CONCLUSIONS
It is apparent that essential oils should be considered as alternative preharvest natural fungicides. Further investigation on natural maize grain might be useful to study the effectiveness of these essential oils in the presence of natural mycoflora of maize grain.
Velluti
A
A
Food Technology Department, Lleida University, CeRTA-UTPV, Lleida, Spain.
Sanchis
V
V
Ramos
A J
AJ
Turon
C
C
Marín
S
S
D000935:Antifungal Agents / Q000494:pharmacology*; D002935:Cinnamomum zeylanicum; D031743:Cymbopogon; D005516:Food Microbiology; D005670:Fusarium / Q000187:drug effects* / Q000378:metabolism; D009822:Oils, Volatile / Q000494:pharmacology*; D031341:Origanum; D027842:Syzygium; D013696:Temperature; D014255:Trichothecenes / Q000378:metabolism; D003313:Zea mays / Q000382:microbiology*; D015025:Zearalenone / Q000378:metabolism
D000935:Antifungal Agents; D009822:Oils, Volatile; D014255:Trichothecenes; D015025:Zearalenone; C007262:deoxynivalenol