Search Results (81)

Broccoli (Brassica oleracea var. italica) by-products represent an abundant and underutilized source of bioactive compounds with potential applications in sustainable food systems. This study aimed to characterize the microbiota associated with different plant fractions (leaves, stems, and heads) of broccoli (Parthenon and Tritón cultivars) and to evaluate the antioxidant and antimicrobial properties of their extracts, using cauliflower as a reference. Microbial counts and fungal identification (ITS sequencing) were performed, while phytochemical profiles were analyzed by HPLC-ESI-QTOF. Antioxidant activity was assessed using DPPH and ABTS assays, and antimicrobial activity under in vitro conditions was evaluated against selected foodborne bacteria and phytopathogenic fungi. Broccoli by-products, particularly leaves, showed lower microbial loads in certain cultivars and were rich in phenolic compounds and glucosinolates; however, higher phenolic content did not always correlate with greater antioxidant activity, highlighting the importance of compound composition. All extracts showed strong antibacterial activity at higher concentrations, especially against Listeria spp. Notably, antifungal activity was selective but relevant, with consistent inhibition observed against Alternaria alternata, while Penicillium purpurogenum and Botrytis cinerea exhibited higher resistance. Overall, these findings highlight the potential of broccoli by-products as sustainable sources of natural bioactive compounds for food applications, particularly in the development of preservation strategies and postharvest treatments. Further studies focusing on individual compounds and their specific biological activities are needed to better understand the mechanisms underlying these effects and to support their application in real food systems. Full article

Botrytis cinerea is a major phytopathogen responsible for significant postharvest losses in plant-derived foods. The increasing resistance to synthetic fungicides has driven the search for sustainable alternatives, including enzyme-based biofungicides. In this study, the proteolytic fraction P1G10 from Vasconcellea pubescens latex was encapsulated in an alginate–chitosan (ALG-CS) matrix to improve its stability and antifungal performance. The encapsulated formulation (ALG-CS-P1G10) retained ~95% enzymatic activity after 8 h under stress conditions (37 °C, 1350 lux), compared with 67% for the free enzyme. In vitro assays demonstrated a dose-dependent inhibition of B. cinerea growth, with an IC₅₀ value of ~11 mg/mL determined using a logistic model. At this concentration, the formulation reduced fungal adhesion by more than 80% and increased sensitivity to cell wall-disrupting agents (Congo Red and Calcofluor White), pointing to alterations in cell wall integrity. Importantly, the encapsulated system provided a more stable and sustained antifungal effect, consistent with a controlled-release mechanism. These results demonstrate that coupling enzyme stabilization with controlled release can improve the functional performance of protease-based antifungal systems, offering a promising strategy for the development of biofungicides in postharvest applications. Full article

Post-harvest diseases caused by phytopathogenic microorganisms generate significant economic losses, particularly in tomato crops affected by Alternaria solani. This study evaluated the effectiveness of cold plasma combined with a bioextract of Bacillus vallismortis as a biological strategy to extend tomato shelf life. In vitro antagonism assays were performed by confronting B. vallismortis against A. solani. Additionally, shelf-life tests were conducted on tomatoes treated with Bacillus cells and Bacillus cell-free bioextract (BCFB), followed by inoculation with A. solani spores, assessing incidence, severity, weight loss, and microbiological parameters over time. Subsequently, tomatoes were treated with cold plasma in combination with BCFB and reevaluated. Results showed significant antagonistic activity, with B. vallismortis and BCFB inhibiting A. solani by 75% and 50%, respectively. In untreated tomatoes, BCFB reduced disease incidence to 66.66% and severity to scale 2, compared to 100% incidence and scale 5 severity in controls. The combined treatment with cold plasma and BCFB showed the highest effectiveness, completely inhibiting A. solani (0% incidence, scale 0 severity), with tomatoes remaining healthy after 25 days. These findings demonstrate that cold plasma combined with B. vallismortis represents an effective and sustainable alternative for controlling post-harvest phytopathogens and extending tomato shelf life. Full article

The agricultural sector generates substantial waste that harms both the environment and human health. This study aimed to utilise Metschnikowia yeasts to convert native agricultural wastes without chemical pretreatment. Ten Metschnikowia isolates were assessed using API tests to identify their assimilation profiles and enzymatic activities. Yeast growth was evaluated via the plate count method. The culture media containing molasses, brewery spent grain, and postharvest sunflower parts were characterised chromatographically, and the in vitro impact on Verticillium tenerum phytopathogen was evaluated. The effect of the yeast preparations on Caco-2, IEC-6, and HaCaT cell lines was also investigated. Solid waste materials without preliminary chemical pretreatment supported yeast multiplication to 4.5 × 10⁷–1.3 × 10⁸ CFU/mL. The metabolite composition and enzymatic activity of lipase, glucosidase, and protease in post-culture media suggest that they may act as growth inhibitors of the Verticillium strain. For post-cultivation samples, inhibition coefficients were equal to 1.24–2.00, depending on the kind of substrate and yeast strain used. Antimicrobial activity was also noted in cell-free samples after yeast cultivation on sunflower stalks and brewery spent grain. The toxicological analysis showed that the yeast preparations did not cause toxic effects on the tested cell lines. This research offers a sustainable approach using Metschnikowia yeasts, highlighting the importance of a holistic method that combines microbiological, biochemical, and toxicological aspects for sustainable waste management and the development of new applications, such as feed supplements and biocontrol agents. Full article

Postharvest losses of fruits and vegetables are a global problem that directly affect food security, the economy, and the environment. These losses are mainly associated with fungal diseases during storage. Due to the limitations of synthetic fungicides, including the development of resistance and risks to human health, there is growing interest in sustainable disease control strategies. This scoping review analyzes the potential of the yeast Metschnikowia pulcherrima as a biocontrol agent for postharvest phytopathogens, based on the scientific literature published between 2014 and 2026. The reviewed studies identify several antagonistic mechanisms, including competition for nutrients and space, the production of organic volatile compounds, hydrolytic enzyme activity, biofilm formation, and the induction of resistance in fruits. In vitro and in vivo assays show that M. pulcherrima effectively reduces postharvest disease incidence and severity caused by certain fungi. Furthermore, its synergistic effect when combined with emerging technologies is notable. The results highlight its potential as a sustainable alternative to synthetic fungicides, although further studies are needed for large-scale commercial application. Full article

Feijoa fruits are known for their pronounced post-harvest ripening. Phytopathogen-infected specimens pose a significant risk to storage stability and overall fruit quality. Early detection and removal of defective fruits during the initial storage stages are critical for maintaining market value and preventing the spread of disease. In this study, we analyze how the multispectral reflectance properties of the feijoa surface change in response to various defects. ‘Superba’ cultivar fruits were selected, including healthy controls and samples exhibiting bruises, anthracnose, stink bug damage, tissue suberization, and gray mold. Biochemical analyses were conducted to measure the levels of organic acids, sugars, ascorbic acid, and total polyphenols. Multispectral imaging was performed with a 12-channel camera operating in the 400–1000 nm wavelength range. Results showed that the fruits affected by gray mold had the lowest concentrations of malic and citric acids but the highest levels of succinic acid. Fruits with anthracnose or insect damage exhibited the highest sugar content. Distinct differences in spectral reflectance were observed between healthy and affected areas of fruit. Based on these findings, an image processing algorithm for defective fruit detection was developed. Full article

Postharvest fungal decay is a primary cause of losses in blueberries, motivating the development of sustainable alternatives to conventional fungicides. This study aimed to develop and evaluate antifungal active films based on polylactic acid (PLA) enriched with citronella essential oil to control phytopathogenic fungi associated with blueberry spoilage. PLA films containing 7.5, 10, and 12.5% (w/w) citronella essential oil were produced by solvent casting and characterized for water vapor transmission rate and nanomechanical properties. The antifungal effect was tested in vitro against Epicoccum nigrum, Alternaria alternata, and Cladosporium herbarum. Active films exhibited concentration-dependent antifungal activity, with C. herbarum being the most sensitive fungus. The incorporation of citronella essential oil did not significantly alter the water vapor barrier properties of PLA, while mechanical analysis revealed a reduction in elastic modulus only at the highest concentration. The antifungal mechanism was elucidated using scanning electron microscopy, fatty acid profiling, absorbance at 260 nm, and conductivity measurements. The results indicate that the released citronella essential oil induced membrane disruption and morphological damage in fungal hyphae, with species-specific responses. Overall, PLA–citronella essential oil films represent a promising biodegradable packaging solution to control postharvest blueberry losses. Full article

Phytopathogenic fungi pose a critical threat to global food security through substantial pre- and post-harvest crop losses, intensified by climate change and fungicide resistance. To address this, we synthesized low-concentration chitosan–inorganic oxide nanocomposites (CS-SiO₂, CS-ZnO, CS-CuO) via ionic gelation, a green and scalable method. Comprehensive characterization (DLS, UV-Vis, FTIR, XRD, SEM) confirmed nanocomposite formation, CS-SiO₂ exhibited uniform particle sizes (200–250 nm), while CS-CuO showed slightly larger particles, all with excellent dispersity. Zeta potential analysis confirmed strong colloidal stability, with pure chitosan nanoparticles (CSNPs) displaying a surface charge of +12.9 mV, while all nanocomposites retained positive charges, enhancing adhesion to negatively charged fungal membranes. In vitro antifungal assays against Alternaria alternata, Botrytis cinerea, Colletotrichum graminicola, and Fusarium graminearum demonstrated hierarchical efficacy: CS-CuO > CS-ZnO > CS-SiO₂, with CS-CuO achieving >80% growth inhibition against B. cinerea and A. alternata. SEM revealed severe hyphal damage and spore collapse in CS-CuO-treated fungi, attributed to synergistic reactive oxygen species (ROS) generation and chitosan-mediated membrane disruption. In vivo trials on B. cinerea-infected apples showed CS-CuO reduced lesion area by 81% and elevated host defense markers, including a 1.5-fold increase in total phenolic content and higher DPPH radical scavenging activity compared to controls. These nanocomposites, particularly CS-CuO, offer a sustainable, dual-action solution direct antifungal activity and enhanced host resilience while minimizing environmental impact. By integrating scalable synthesis, eco-compatibility, and efficacy, this work advances chitosan–inorganic oxide nanocomposites as viable alternatives to conventional fungicides, with immediate potential for agricultural and postharvest applications. Full article

Essential oils (EOs), complex volatile compounds synthesized by plants, represent a vital class of natural products that are increasingly significant in scientific research due to their diverse biological properties and broad-spectrum medicinal applications. This study provides a comprehensive overview of EOs, commencing with a historical perspective and detailing their applications. It systematically catalogs their primary botanical sources, with specific examples of the most common and important plant families, including Lamiaceae (e.g., sage, oregano, thyme), Verbenaceae (vervain), Magnoliaceae (magnolia), Rutaceae (lemon), Myrtaceae (eucalyptus) and Lauraceae (cinnamon). A key focus is their antifungal activity, including the bioactive constituents involved and their mechanisms of action, with particular emphasis on their defense against pathogenic postharvest fungi. This includes an analysis of the key bioactive constituents responsible for these bioeffects and an exploration of their possible mechanisms of action against phytopathogenic fungi, with particular emphasis on postharvest pathogens infecting several crops. The discussion further highlights the role of EOs as sustainable alternatives to synthetic fungicides for controlling plant diseases that avoid the negative ecological and public health impacts associated with conventional agrochemicals. The study addresses these objectives by describing methods for testing antimicrobial efficacy, including kill-time studies, LD₅₀ determination, growth-curve analysis, the poisoned food technique, Spore-germination assays, and metabolic CO₂ measurement. The current review also highlights some recent studies reviewing the in vitro and in vivo antifungal performance of specific EOs against postharvest diseases. Full article

Phytopathogenic fungi that affect postharvest are a serious problem for agriculture, so this research explores the antifungal potential of three different “rosemary” species growing in Chile through in vitro and in silico assays. The analysis of essential oils (GC/MS) reveals the dominant constituents of Salvia rosmarinus (camphor: 66.96%), Baccharis linearis (lachnophyllum ester: 88.62%) and Fabiana imbricata (an oxygenated sesquiterpene: 43.66%) and shows profiles that differ from chemotypes of the same species from other areas of the world. B. linearis oil was shown to be a versatile antifungal substance, inhibiting Botrytis cinerea and Monilinia fructicola at moderate concentrations; F. imbricata oil stood out as a major inhibitor of mycelial growth of the same isolate of M. fructicola used to test B. linearis oil (EC₅₀ of 15.86 + 0.67 µg/mL) and completely inhibited of its conidial germination. In silico assays confirmed the complexity of interactions of F. imbricata sequiterpenoids with catalytic sites of succinate dehydrogenase and catalase 2, key enzymes in mycelial growth and in maintaining redox homeostasis in the early development of M. fructicola, respectively. The results of this research make F. imbricata a good candidate for the development of a formulation applicable in vivo as an eco-friendly post-harvest antifungal agent. Full article

Postharvest diseases represent a critical challenge for global agriculture, resulting in substantial economic losses and threatening worldwide food security. Species of the genus Colletotrichum stand out among the main phytopathogens for being responsible for up to 40% of postharvest losses in various crops, including Capsicum species. This study evaluated the antifungal activity of two Streptomyces strains isolated from Amazonian sediments against different Colletotrichum species, with a focus on C. scovillei, the causal agent of anthracnose in Capsicum chinense fruits. Multilocus phylogenetic analyses indicated that strain APUR 32.5 possibly represents a new species, while MPUR 40.3 was identified as Streptomyces murinus. Both strains exhibited in vitro antifungal activity against seven Colletotrichum species, with inhibition percentages ranging from 56.3% to 88.6%. In fruit bioassays, S. murinus MPUR 40.3 reduced the incidence of anthracnose by 95%, while Streptomyces sp. APUR 32.5 achieved a 39.25% reduction. Scanning electron microscopy revealed complementary mechanisms of antifungal action, with MPUR 40.3 acting during the early infection stages through germination tube lysis, while APUR 32.5 targeted established mycelial structures through hyphal degradation. Additionally, both strains demonstrated plant growth-promoting capacity and exhibited biotechnologically relevant characteristics, including production of hydrolytic enzymes, siderophores, and phosphate solubilization ability. These results highlight the biotechnological promise of these Amazonian isolates as multifunctional agents for the sustainable management of anthracnose in Capsicum peppers. Full article

Certain essential oils (EOs) from aromatic plants have shown potent antifungal effects. In this work, an in vitro study was conducted to examine the antifungal effect of EOs obtained from Greek flora aromatic plants that belong to the Lamiaceae family on two phytopathogenic fungi. Specifically, Satureja horvatii ssp. macrophylla, Coridothymus capitatus, and Origanum vulgare ssp. hirtum were tested against Alternaria sp., which causes tomato black spot, and Fusarium sp., which causes potato tuber dry rot during storage. The antifungal activity of the EOs was assessed using fumigant assays, and their chemical composition was analyzed using gas chromatography–mass spectrometry (GC–MS). After 8 days of incubation at 26 ± 1 °C, the EOs of O. vulgare ssp. hirtum and C. capitatus completely inhibited mycelial growth at 2 µL plate⁻¹ in the case of Fusarium sp. and at 3 µL plate⁻¹ in the case of Alternaria sp. S. horvatii ssp. macrophylla completely inhibited the mycelial growth of Fusarium sp. at 3 µL plate⁻¹ and that of Alternaria sp. at 4 µL plate⁻¹. All the essential oils used in the experiments were rich in carvacrol (41.4–70.0%), while thymol levels ranged from 0% to 18.9%. This fumigant effect could be further evaluated for the fruits’ postharvest protection from phytopathogenic fungi during storage. Full article

Background/Objectives: Botrytis cinerea is a necrotrophic fungal plant pathogen responsible for the gray mold disease, affecting several crops of economic importance worldwide. The primary line of control for the disease in the field and post-harvest fruits includes the application of fungicides. However, the emergence of fungal populations resistant to one or more fungicides has increased their application and diminished their effectiveness. Looking at new control strategies, metallic nanoparticles have appeared as a promising alternative for disease treatment. Green-synthesized copper oxide nanoparticles (CuONPs) are considered a feasible alternative, aiming to reduce the generation of environmentally toxic waste through chemical methods. Methods: In this work, CuONPs biosynthesized using the supernatant of Trichoderma asperellum and Trichoderma ghanense were evaluated to determine their antifungal activity against B. cinerea. Results: Four different formulations of CuONPs were obtained: Ta1, Ta2, Tg1, and Tg2. All formulations displayed antifungal properties, with Tg2 being the most effective and having a high potential in controlling the phytopathogen. CuONPs in the Tg2 formulation were quasi-spherical, ranging in size from 1 to 2.7 nm. Conclusions: Furthermore, Tg2 demonstrated greater efficacy than the copper-based commercial fungicide NORDOX^® 75W, which showed no inhibitory effect on B. cinerea mycelial growth. In summary, the CuONPs reported in this work offer a sustainable and effective alternative for managing the gray mold disease. Full article

This study explores tomato agri-food residues as sources of bacteria with bioprotective potential to enhance product shelf-life and safety. A total of 245 bacterial strains were isolated, comprising predominantly Pseudomonas (52%) and Bacillus (44%) spp., with lactic acid bacteria (LAB) present at lower levels (4%). The antimicrobial activity of these isolates was assessed against pathogenic and spoilage bacteria and phytopathogenic molds. Notably, the Bacillus isolate TRB1-7 exhibited moderate activity against L. monocytogenes (inhibition halo diameter: 10.64 mm), while Pseudomonas and LAB isolates showed limited or no inhibition. Antifungal assays highlighted significant antifungal potential for Bacillus isolates. Results showed that 16% and 15% of the 245 isolates inhibited F. oxysporum and C. acutatum growth, respectively. Nine of these isolates underwent acid-adaptation and were evaluated against the selected molds using Potato Dextrose Agar (PDA) at pH 4.0 to simulate tomato conditions. Only isolate BRZ3-2, identified as B. aerius, was adapted to acidic conditions and inhibited F. oxysporum by 25%. Experiments on tomato-based agar at the same pH showed no inhibition by Bacillus isolates. These results suggest that tomato microbiota harbors acid-tolerant Bacillus strains with potential for post-harvest bio-preservation. Further studies on strains TRB1-7 and BRZ3-2 are required to develop effective bioprotective applications. Full article

Postharvest fungal rot causes significant economic losses in the agroindustry. Current control methods involving the use of synthetic fungicides are becoming increasingly ineffective and pose environmental risks. This necessitates exploring sustainable alternatives, such as essential oils derived from medicinal plants, to achieve safer and effective disease control. This research examined the chemical composition and efficacy of essential oils from Aloysia citriodora, Aloysia polystachya and their compounds against the postharvest rot fungi Monilinia fructicola, Monilinia laxa, and Botrytis cinerea. The main compounds of essential oils were analyzed by GC/MS and revealed differences in their composition. A. citriodora is characterized by the presence of spathulenol and caryophyllene oxide. In contrast, A. polystachya is characterized by the predominance of carvone. The results show that the essential oil of A. citriodora and the compound farnesol are able to inhibit the three pathogens. Notably, against M. fructicola, the EC₅₀ values were 61.89 μg/mL and 72.18 μg/mL, respectively. Against B. cinerea, the EC₅₀ values were 85.34 μg/mL and 47.6 μg/mL. Molecular docking also showed that farnesol has affinity for the enzyme succinate dehydrogenase suggesting a possible mechanism of action. This compound and A. citriodora essential oil show potential in the control of phytopathogens. Full article