GRAS, plant- and animal-derived compounds as alternatives to conventional fungicides for the control of postharvest diseases of fresh horticultural produce

Abstract

Postharvest decay caused by fungal pathogens is one of the most important factors causing economic losses for the worldwide industry of fresh horticultural produce. Despite the positive results of the use of conventional chemical fungicides, alternatives for decay control are needed because of increasing concerns related to their widespread and continued use. Low-toxicity chemical alternatives evaluated for control of postharvest diseases of temperate, subtropical and tropical fruit, and fruit-like vegetables are reviewed. These compounds should have acceptable antifungal activity with known and very low toxicological effects on mammals and minimal impact on the environment. In addition, they should be exempt from residue tolerances on agricultural commodities. Authorities confirm these characteristics by approving them as food additives or preservatives or as generally regarded as safe (GRAS) substances. Among these, the most important are inorganic or organic salts, e.g. carbonates, sorbates, benzoates, paraben salts, etc., and composite edible coatings formulated with antifungal ingredients. Hydrocolloids (polysaccharides such as cellulose derivatives, alginates, pectins, or gums, and various plant proteins) and food-grade lipids are the main components of the matrix of composite coatings. Interesting antifungal ingredients for edible coatings include GRAS salts, essential oils, and antagonistic microorganisms. Low-toxicity chemicals of natural origin include plant extracts and essential oils, antifungal peptides and small proteins, and coatings based on chitosan or plant gels like those from Aloe spp. Efficacy and overall performance, advantages, disadvantages, limitations, and potential combinations of these alternatives in hurdle technologies for postharvest decay control are discussed.

UHPLC-Q-TOF/MS-Based Metabolomics Approach Reveals the Antifungal Potential of Pinocembroside against Citrus Green Mold Phytopathogen

“…However, the use of synthetic fungicides has received worldwide concern due to their potential undesirable biological effects in humans, animals, and the environment. Moreover, such synthetic antifungal agents remain as toxic residues and can cause public health concerns, the emergence of resistant fungi, and environmental pollution [11,12]. Keeping in view these issues, metabolism level in P. digitatum treated with PiCB, we used microscopy and UHPLC-Q-TOF/MS-based non-targeted metabolomics.…”

The Antifungal Potential of Carvacrol against Penicillium Digitatum through 1H-NMR Based Metabolomics Approach

“…Moreover, it has also been tried to explore new preservation technologies that can replace synthetic fungicides. Compared with synthetic fungicides, natural antifungal substances have attained much attention in recent years [6][7][8][9].Various essential oils refined from Melaleuca alternifolia have strong inhibitory effects on multiple fungal strains, particularly P. italicum Wehmer and P. digitatum Sacc., and hence can be used as natural preservatives in agricultural and food processing [10]. Previously we have reported that cinnamaldehyde contained in cinnamon has a good antifungal effect against P. italicum and clarifies the method for dynamic detection of the antifungal effect of cinnamaldehyde [11].…”

Alternative management technologies for postharvest disease control: The journey from simplicity to complexity

“…Other methods that were explored included the use of chitosan Meng et al, 2010;Romanazzi et al, 2016a), glucose (Sui and Liu, 2014), the integration of UV-C with antagonists (Stevens et al, 1997), combining the use of antagonists with heat treatments (Conway et al, 2004;Liu et al, 2011), organic salts and surfactants (Nigro et al, 2006), modified atmosphere storage (Spotts et al, 2002;Karabulut and Baykal, 2004), and ethylene inhibitors (Osman et al, 2011). The use of various physical treatments, natural plant and animal products and the identification and potential of plant and fungal derived volatile organic compounds (VOCs) are detailed in this issue by Usall et al (2016), Palou et al (2016) and Mari et al (2016), respectively. The search for stress resistant antagonists was also pursued (Sui et al, 2015).…”