title: Inhibitory Effect of Cinnamaldehyde, Citral, and Eugenol on Aflatoxin Biosynthetic Gene Expression and Aflatoxin B1 Biosynthesis in Aspergillus flavus.
abstract: In order to reveal the inhibitory effects of cinnamaldehyde, citral, and eugenol on aflatoxin biosynthesis, the expression levels of 5 key aflatoxin biosynthetic genes were evaluated by real-time PCR. Aspergillus flavus growth and AFB1 production were completely inhibited by 0.80 mmol/L of cinnamaldehyde and 2.80 mmol/L of citral. However, at lower concentration, cinnamaldehyde (0.40 mmol/L), eugenol (0.80 mmol/L), and citral (0.56 mmol/L) significantly reduced AFB1 production with inhibition rate of 68.9%, 95.4%, and 41.8%, respectively, while no effect on fungal growth. Real-time PCR showed that the expressions of aflR, aflT, aflD, aflM, and aflP were down-regulated by cinnamaldehyde (0.40 mmol/L), eugenol (0.80 mmol/L), and citral (0.56 mmol/L). In the presence of cinnamaldehyde, AflM was highly down-regulated (average of 5963 folds), followed by aflP, aflR, aflD, and aflT with the average folds of 55, 18, 6.5, and 5.8, respectively. With 0.80 mmol/L of eugenol, aflP was highly down-regulated (average of 2061-folds), followed by aflM, aflR, aflD, and aflT with average of 138-, 15-, 5.2-, and 4.8-folds reduction, respectively. With 0.56 mmol/L of citral, aflT was completely inhibited, followed by aflM, aflP, aflR, and aflD with average of 257-, 29-, 3.5-, and 2.5-folds reduction, respectively. These results suggest that the reduction in AFB1 production by cinnamaldehyde, eugenol, and citral at low concentration may be due to the down-regulations of the transcription level of aflatoxin biosynthetic genes. Cinnamaldehyde and eugenol may be employed successfully as a good candidate in controlling of toxigenic fungi and subsequently contamination with aflatoxins in practice.
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Liang
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Fuguo
authors.initials: F
authors.lastname: Xing
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Jonathan Nimal
authors.initials: JN
authors.lastname: Selvaraj
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Liu
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Limin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Huijuan
authors.initials: H
authors.lastname: Hua
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Lu
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Yueju
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Inst. of Food Science and Technology, Chinese Academy of Agricultural Sciences, Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, 100193, P. R. China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000171:Acrolein / Q000031:analogs & derivatives* / Q000494:pharmacology; D000080462:Acyclic Monoterpenes; D016604:Aflatoxin B1 / Q000096:biosynthesis*; D000348:Aflatoxins; D054458:Amplified Fragment Length Polymorphism Analysis; D001231:Aspergillus flavus / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D005054:Eugenol / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects*; D005800:Genes, Fungal; D039821:Monoterpenes / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D000080462:Acyclic Monoterpenes; D000348:Aflatoxins; D039821:Monoterpenes; D005054:Eugenol; D000171:Acrolein; D016604:Aflatoxin B1; C012843:cinnamaldehyde; C007076:citral
keywords: Aflatoxin; Aspergillus flavus; gene expression; plant extracts; real-time PCR