Polysaccharide Matrices for the Encapsulation of Tetrahydrocurcumin-Potential Application as Biopesticide against Fusarium graminearum.

Anne Loron,Vesta Navikaitė-Šnipaitienė,Christian Gardrat,Véronique Coma,Deimantė Rosliuk,Ramunė Rutkaitė

doi:10.3390/molecules26133873

Abstract

Cereals are subject to contamination by pathogenic fungi, which damage grains and threaten public health with their mycotoxins. Fusarium graminearum and its mycotoxins, trichothecenes B (TCTBs), are especially targeted in this study. Recently, the increased public and political awareness concerning environmental issues tends to limit the use of traditional fungicides against these pathogens in favor of eco-friendlier alternatives. This study focuses on the development of biofungicides based on the encapsulation of a curcumin derivative, tetrahydrocurcumin (THC), in polysaccharide matrices. Starch octenylsuccinate (OSA-starch) and chitosan have been chosen since they are generally recognized as safe. THC has been successfully trapped into particles obtained through a spray-drying or freeze-drying processes. The particles present different properties, as revealed by visual observations and scanning electron microscopy. They are also different in terms of the amount and the release of encapsulated THC. Although freeze-dried OSA-starch has better trapped THC, it seems less able to protect the phenolic compound than spray-dried particles. Chitosan particles, both spray-dried and lyophilized, have shown promising antifungal properties. The IC50 of THC-loaded spray-dried chitosan particles is as low as 0.6 ± 0.3 g/L. These particles have also significantly decreased the accumulation of TCTBs by 39%.

Highlights

Fusarium graminearum has been classed as the fourth most important fungal plant pathogen regarding scientific and economic criteria [1]
F. graminearum can produce 4-deoxynivalenol (DON), which is a worldwide-regulated toxin, and some derivatives of DON, all DONs belonging to the trichothecenes B (TCTBs) family
Current strategies to tackle fungal pathogens mostly rely on synthetic fungicides, some of them being endocrine disruptors [3,4,5], being toxic for the environment [6] or inducing the apparition of resistant strains [7]

Summary

Introduction

Fusarium graminearum has been classed as the fourth most important fungal plant pathogen regarding scientific and economic criteria [1]. This species is responsible for severe wheat, maize or barley diseases. Fungal contamination is often associated with the presence of mycotoxins, which are toxic secondary metabolites accumulated by the fungi. These mycotoxins represent a major threat for both human and animal health. Current strategies to tackle fungal pathogens mostly rely on synthetic fungicides, some of them being endocrine disruptors [3,4,5], being toxic for the environment [6] or inducing the apparition of resistant strains [7]

Methods

Results

Discussion

Conclusion