title: Inactivation effect of electron beam irradiation on fungal load of naturally contaminated maize seeds.
abstract: BACKGROUND
  This work focuses on the effect of accelerated electrons (0.1-6.2 kGy) on naturally attached fungi on maize seeds. The fungal viability and corresponding inactivation kinetics were determined. The inactivation and radiosensitivity of the most abundant species in the contaminant fungi detected on maize seeds (Aspergillus spp., Penicillium spp. and Fusarium spp.) are discussed.
  
  
  RESULTS
  Fungal contamination of maize seeds decreased significantly with increasing irradiation dose. The survival curve of total fungi determined by the blotter test showed a sigmoidal pattern that can be attributed to the mixture of fungal subpopulations with different radiation sensitivities. This behaviour could be modelled well (R²  = 0.995) with a modified Gompertz equation. The predicted values for shoulder length and inactivation rate were 0.63 ± 0.10 kGy and 0.44 ± 0.04 kGy⁻¹ respectively. The sensitivity of the most common fungi to electron beam treatment followed the order Penicillium spp. > Fusarium spp. > Aspergillus spp., with total inactivation at irradiation doses of 1.7, 2.5 and 4.8 kGy respectively.
  
  
  CONCLUSIONS
  The effect of electron beam treatment against fungi on naturally contaminated maize seeds depended on irradiation dose, allowing the control of maize fungal load.
authors.affiliation: Electron Accelerators Laboratory, National Institute for Lasers, Plasma and Radiation Physics, 409 Atomistilor Street, PO Box MG-36, RO-077125, Bucharest-Magurele, Romania.
authors.forename: Monica R
authors.initials: MR
authors.lastname: Nemţanu
authors.forename: Mirela
authors.initials: M
authors.lastname: Braşoveanu
authors.forename: Gürsel
authors.initials: G
authors.lastname: Karaca
authors.forename: İsmail
authors.initials: İ
authors.lastname: Erper
mesh_terms: D000465:Algorithms; D001230:Aspergillus / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology / Q000528:radiation effects*; D055984:Cathode Ray Tube; D018556:Crops, Agricultural / Q000382:microbiology* / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D004583:Electrons; D005506:Food Contamination / Q000517:prevention & control; D005519:Food Preservation; D005670:Fusarium / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology / Q000528:radiation effects*; D007700:Kinetics; D050296:Microbial Viability / Q000528:radiation effects; D010407:Penicillium / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology / Q000528:radiation effects*; D011836:Radiation Tolerance; D012639:Seeds / Q000382:microbiology* / Q000528:radiation effects; D013045:Species Specificity; D013172:Spores, Fungal / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology / Q000528:radiation effects; D014421:Turkey; D003313:Zea mays / Q000382:microbiology* / Q000528:radiation effects
keywords: Gompertz model; food safety; irradiation; radiosensitivity; survival curve