Dimethyl Dicarbonate as a Food Additive Effectively Inhibits Geotrichum citri-aurantii of Citrus

Abstract

Dimethyl dicarbonate (DMDC), a food additive, can be added to a variety of foods as a preservative. This study aimed to evaluate the inhibitory effects of DMDC on Geotrichum citri-aurantii in vitro and in vivo, as well as the potential antifungal mechanism. In vitro experiments showed that 250 mg/L DMDC completely inhibited the growth of G. citri-aurantii and significantly inhibited spore germination by 96.33%. The relative conductivity and propidium iodide (PI) staining results showed that DMDC at 250 mg/L increased membrane permeability and damaged membrane integrity. Malondialdehyde (MDA) content and 2, 7-Dichlorodihydrofluorescein diacetate (DCHF-DA) staining determination indicated that DMDC resulted in intracellular reactive oxygen species (ROS) accumulation and lipid peroxidation. Scanning electron microscopy (SEM) analysis found that the mycelia were distorted and the surface collapsed after DMDC treatment. Morphological changes in mitochondria and the appearance of cavities were observed by transmission electron microscopy (TEM). In vivo, 500 mg/L DMDC and G. citri-aurantii were inoculated into the wounds of citrus. After 7 days of inoculation, DMDC significantly reduced the disease incidence and disease diameter of sour rot. The storage experiment showed that DMDC treatment did not affect the appearance and quality of fruits. In addition, we found that DMDC at 500 mg/L significantly increased the activity of citrus defense-related enzymes, including peroxidase (POD) and phenylalanine ammonia-lyase (PAL). Therefore, DMDC could be used as an effective method to control citrus sour rot.

Ferric Chloride Controls Citrus Anthracnose by Inducing the Autophagy Activity of Colletotrichum gloeosporioides

“…As discussed above, mancozeb and copper compounds alone or coupled with fosetyl-Al are chemical fungicides that are commonly used in agriculture [ 4 , 5 , 6 ]. However, the uncontrolled use of these agents can promote the occurrence of fungicide-resistant pathogenic fungi, in addition to affecting human and environmental health [ 7 , 24 ]. Autophagy research has mainly focused on basic biology, whereas relatively few studies have been conducted on plants and plant pathogens.…”

Yeast Warriors: Exploring the Potential of Yeasts for Sustainable Citrus Post-Harvest Disease Management

“…The microscopic examination of G. citri-aurantii reveals distinctive characteristics of its mycelium and spores. In this sense, Liu et al [64] reported that the mycelium of G. citriaurantii appears as a network of branching, septate hyphae, which are typically hyaline and thin-walled, form a dense and intricate mat, spreading across the substrate. The spores of G. citri-aurantii are a key diagnostic feature and are typically spherical or ellipsoidal in shape, measuring from approximately 5 to 15 µm in diameter [65].…”

Screening of Oxygenated Aromatic Compounds for Potential Antifungal Activity against Geotrichum citri-aurantii through Structure–Activity Relationship Analysis

“…citri-aurantii) is one of the disaster postharvest diseases in citrus fruits . This disease cannot be effectively controlled by most commercial registered fungicides for controlling postharvest diseases in citrus fruits, such as imazalil, pyrimethanil, thiabendazole, and fludioxonil. , The fungicides sodium o -phenylphenate, propiconazole, and guazatine can effectively control sour rot; however, their use is strictly restricted because of their risk of fruit injury and human safety and because they are not registered in many countries. , Consequently, it is imperative to screen and/or design novel and safe antifungal agent candidates that can control G. citri-aurantii infection in citrus fruits.…”