Determination of metabolites of Geotrichum citri‐aurantii treated with peppermint oil using liquid chromatography‐mass spectrometry and gas chromatography‐mass spectrometry

• Published in: Journal of food biochemistry 2019-03, Vol.43 (3), p.e12745-n/a
• Main Authors: Qi, Jianrui, Pang, Yaxing, An, Peipei, Jiang, Guoshan, Kong, Qingjun, Ren, Xueyan
• Format: Article
• Language: English
• Subjects: G. citri‐aurantii; GC‐MS; LC‐MS; metbolomics; peppermint oil
• ISSN: 0145-8884; 1745-4514
• DOI: 10.1111/jfbc.12745

Sour rot is a leading disease of citrus fruit caused by the postharvest pathogen Geotrichum citri‐aurantii. It has been reported that essential oils can be used as substitutes for synthetic fungicides to control the pathogen. In this study, changes in metabolites and antifungal effects of G. citri‐aurantii treated with peppermint oil (PO) were investigated. The inhibition rate of the mycelial growth increased as the PO concentration increased, and 6 μl PO/disk resulted in a radial growth inhibition of 79.2%. The electrical conductivity of G. citri‐aurantii treated with PO increased compared to the control. By comparing the metabolic profiles of treated and untreated G. citri‐aurantii cells, a total of 53 distinct metabolites 9 were up‐regulated and 44 were down‐regulated were found, including 16 lipid metabolites, 6 carbohydrate metabolites, 2 amino acid metabolites, 5 alcohols, 2 glycoside metabolites, and 3 ketone metabolites, etc, and these metabolites are involved in 25 major metabolic pathways. Practical applications Chemical fungicides can effectively control G. citri‐aurantii during fruit postharvest period. However, synthetic chemical fungicides have gradually led to buildup of resistance of fungil, which seriously causes the frequent of food‐borne diseases. PO extracted from natural plants can be used as natural additive in many foods due to their antioxidant, antibacterial, and antifungal properties. Therefore, PO can be considered as a promising bacteriostatic agent for the defense of G. citri‐aurantii during fruit postharvest period.