Hexanal Vapor Induced Resistance against Major Postharvest Pathogens of Banana (Musa acuminata L.)

Abstract

Hexanal, a C-6 aldehyde has been implicated to have antimicrobial properties. Hence, this study was conducted to determine the antifungal activities of hexanal vapor against major postharvest pathogens of banana viz., Colletotrichum gloeosporioides and Lasiodiplodia theobromae. The pathogens were cultured in vitro and exposed to hexanal vapor at 600, 800, 1,000 and 1,200 ppm. Mycelial growth of both fungal pathogens were inhibited completely at 800 ppm and the incidence of anthracnose and stem-end rot diseases reduced by 75.2% and 80.2%, respectively. The activities of peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase and glucanase had transiently increased in hexanal vapor treated banana by 5 to 7 days and declined thereafter. Postharvest treatment of banana with hexanal vapor resulted in phospholipase D inhibition and also resulted in cell wall thickening of the treated fruit, which impeded the penetration of the pathogenic spores. This was further confirmed by scanning electron micrographs. The defense-related protein intermediaries had increased in hexanal vapor treated banana fruit, which suggests induced resistance against C. gloeosporioides and L. theobromae, via., the phenylpropanoid pathway which plays a significant role in hindering the pathogen quiescence. Delayed ripening due to inhibition of phospholipase D enzyme, inhibition of mycelial growth and induced systemic resistance by defense enzymes collectively contributed to the postharvest disease reduction and extended shelf life of fruit.

Combatting plant diseases with ant chemicals: A review and meta‐analysis

“…In addition, as explained above, inhibitory ant chemicals may be tested as agents that can be used to increase storage and shelf life of fruits and vegetables. Hexanal, which is produced by some ant species, is already in use in fruit sprays, as it inhibit post-harvest diseases and, at the same time, is harmless to humans (Anusha et al, 2016;Dhakshinamoorthy et al, 2020). Other ant compounds may have similar potentials.…”

TMT-Based Quantitative Proteomics and Non-targeted Metabolomic Analyses Reveal the Antibacterial Mechanism of Hexanal against Vibrio parahaemolyticus

“…9 It has been reported that hexanal possessed broad-spectrum antimicrobial activity against fungus and bacteria. 10,11 For example, hexanal inhibited the growth of Penicillium expansum, Botrytis cinerea, Escherichia coli, Pseudomonas fluorescens, and Erwinia carotovora. 10,12,13 Due to its "green" odor, hexanal was often applied to control pathogenic and spoilage bacteria associated with fruits, vegetables, and their products.…”

“…10,12,13 Due to its "green" odor, hexanal was often applied to control pathogenic and spoilage bacteria associated with fruits, vegetables, and their products. 10,14,15 Significantly, hexanal is also one of the characteristic flavor components of aquatic products, 16,17 which is often ignored. To the best of our knowledge, there is few report on the anti-V. parahaemolyticus effect of hexanal.…”

“…Hexanal is a naturally occurring aldehyde in plants and has been approved as a food additive by the US FDA . It has been reported that hexanal possessed broad-spectrum antimicrobial activity against fungus and bacteria. , For example, hexanal inhibited the growth of Penicillium expansum, Botrytis cinerea, Escherichia coli, Pseudomonas fluorescens, and Erwinia carotovora. ,, Due to its “green” odor, hexanal was often applied to control pathogenic and spoilage bacteria associated with fruits, vegetables, and their products. ,, Significantly, hexanal is also one of the characteristic flavor components of aquatic products, , which is often ignored. To the best of our knowledge, there is few report on the anti-V.…”

“…10,11 For example, hexanal inhibited the growth of Penicillium expansum, Botrytis cinerea, Escherichia coli, Pseudomonas fluorescens, and Erwinia carotovora. 10,12,13 Due to its "green" odor, hexanal was often applied to control pathogenic and spoilage bacteria associated with fruits, vegetables, and their products. 10,14,15 Significantly, hexanal is also one of the characteristic flavor components of aquatic products, 16,17 which is often ignored.…”