Cera pepper (Capsicum pubescens) is an exotic fruit considered as a rich source of nutraceuticals with known benefits for human health and also an economic resource for local producers in Mexico. The present investigation reports on the in vitro and in situ antifungal activity of the essential oil from Mentha piperita and its two major volatiles (menthol and menthone) against Fusarium sambucinum, which is a causal agent of soft rot in cera pepper. The application of these components in pepper fruits previously infected with F. sambucinum caused a significant delay (p < 0.05) in the emergence of soft rot symptoms. This effect was reflected in the maintenance of pH and fruit firmness during a period of 10 days. The nutrimental content of the fruits (protein, fiber, fat and other proximate parameters) was conserved in the same period of time. The nutraceutical content of these fruits was estimated by the quantification of seven carotenoids (violaxanthin, cis-violaxanthin, luteoxanthin, antheraxanthin, lutein, zeaxanthin and β-carotene), ascorbic acid and capsaicinoids (capsaicin and dihydrocapsaicin). According to our results, the essential oil from M. Piperita and its major volatiles exerted a preservative effect on these metabolites. Our findings demonstrated that the essential oil of M. Piperita and its major volatiles represent an ecological alternative for the control of fusariosis caused by F. sambucinum in cera peppers under postharvest conditions.

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The manzano pepper (Capsicum pubescens) is an exportation product that generates substantial earnings for local producers in Mexico. Herein we report on the most relevant metabolic changes that occur during the postharvest rot of manzano peppers caused by Fusarium temperatum. Simultaneously, we describe the effect of the Zanthoxylum limoncello leaf essential oil (ZlEO) and its major volatiles on the control of this devastating disease. According to our results, ZlEO, 2-undecanone (34%), 2-undecenal (32%), and 2-dodecenal (8%) exerted in vitro fungicide activity on F. temperatum (MIC, 104.6–218.3 mg L−1) and a strong in situ fungistatic effect in manzano peppers previously infected with F. temperatum. A differential fungistatic activity was observed for the natural agents assayed. However, the best results were confirmed with 2-dodecenal, which improved the shelf life of infected peppers up to 16 d post-inoculation. The protective effect of ZlEO and its major volatiles resulted in the conservation of fruit firmness, pH, protein, fat, fiber, ascorbic acid, and nutraceuticals of manzano peppers (carotenoids and capsaicinoids). Our findings endorse the potential use of ZlEO and its major volatiles as natural antifungals to prevent the soft rot triggered by F. temperatum.