Submitted to: California Melon Research Board Annual Meeting
Publication Type: Proceedings
Publication Acceptance Date: 11/17/2005
Publication Date: 11/17/2005
Citation: Mcgarvey, J.A., Barak Cunningham, J.D., Miller, W.G. 2005. Surface sanitization of cantaloupes using thymol/cinnamaldehyde. California Melon Research Board Annual Meeting, November 20-23, 2005, Hermosilla, MX.
Technical Abstract: Aims: To characterize the natural microflora of cantaloupe and evaluate a thymol-cinnamaldehyde treatment for bactericidal effects on the cantaloupe surface. Methods and Results: To characterize the bacterial microflora, 16S rRNA gene sequences were amplified, cloned and BLAST analyzed. The most prevalent phyla were Fimicutes and Proteobacteria. The most commonly occurring operational taxonomic unit (OTU) had a 16S rRNA gene sequence 97 to 100% similar to that of Pantoea agglomerans for farms 2, 4, and 5 and represented approximately 16.5, 60, and 24%, respectively. Also highly prevalent was OTUs with 97 to 100% similar to that of Leuconostoc mesenteroides and Arthrobacter bergeri, comprising approximately 29 and 24% of farms 1 and 3, respectively. Coverage estimates of the OTUs identified were 86.1, 71.3, 75.8, 88.9, and 78.7% for libraries from farms 1-5, respectively. Thymol-cinnamaldehyde treatment reduced populations of Salmonella enterica; however, resident populations of genetically related bacteria were unaffected. Conclusions: 16S rRNA gene sequencing revealed that the bacterial community structure of melons from different farms in different geographic locations was similar. We also showed that the bactericidal properties of thymol and cinnamaldehyde reduced the levels of both the normal epiphytic flora of melons and Salmonella spiked onto them.