Search Results (53)

Phytopathogenic fungi cause major agricultural losses worldwide. Their control relies largely on synthetic fungicides, which raise concerns related to environmental impact, resistance development, and human health. Botanical extracts represent a promising, sustainable alternative, and members of the Brassicaceae family are recognized as rich sources of antifungal metabolites. In this study, the antifungal activity of ethanol extracts from Brassica napus and Capsella bursa-pastoris was evaluated against Botrytis cinerea, Colletotrichum acutatum, and Fusarium oxysporum, which are major phytopathogens widely recognized for causing significant diseases in diverse commercial crops worldwide. Antifungal effects on mycelial radial growth and conidial production were assessed in vitro using the amended culture medium assay. Extracts were chemically characterized by LC-DAD-ESI-MS, and a single-Y orthogonal partial least squares (OPLS) analysis was applied to integrate chemical and bioactivity data to identify metabolites associated with antifungal activity. Test botanical extracts showed organ- and pathogen-dependent antifungal activity. B. napus was more active, as seeds reduced B. cinerea growth, and roots strongly suppressed conidiation and inhibited F. oxysporum. In contrast, C. bursa-pastoris was less effective, with only the flower and fruit extracts causing modest reductions in F. oxysporum, while the other extracts were largely inactive. Fourteen metabolites were tentatively identified based on UV-Vis and mass spectral data. Among them, one flavanol and two indole-containing compounds were statistically correlated with antifungal activity, were subsequently isolated, and were structurally confirmed by NMR spectroscopy. These compounds (1–3) exhibited reasonable antifungal activity (IC₅₀ < 40 µM). The integrative covariate-based metabolic profiling approach proved operative for identifying bioactive constituents in the test botanical extracts, supporting the potential of Brassicaceae-derived extracts and their metabolites as natural antifungal agents. Full article

The transition toward a sustainable agri-food system, aligned with agricultural and environmental policy objectives, has increased interest in aromatic plants as non-synthetic pesticide alternatives. This study focused on evaluating the antifungal potential of five specific aromatic plant species, particularly Lavandula dentata, Origanum vulgare, Thymus vulgaris, Salvia officinalis and Rosmarinus officinalis, against the phytopathogenic soil-borne fungi Fusarium oxysporum f.sp. radicis-lycopersici and Verticillium dahliae. During screening, L. dentata and T. vulgaris extracts exhibited strong in vitro fungicidal activity. Bioactive compounds previously detected in both lavender and thyme were identified in their extracts using a triple quadrupole/linear ion trap mass spectrometer. Assessment of in vitro phytoprotective action of L. dentata extract in solid and liquid growth media demonstrated inhibitory effects against F. oxysporum f.sp. radicis-lycopersici at concentrations above 1% v/v, with inhibitory effects of L. dentata extract being observed at concentrations equal to or above 2% v/v. T. vulgaris extract inhibited V. dahliae growth on solid media at concentrations at 1% v/v or above, while inhibitory effects were observed in broth media containing 2% v/v thyme extract. Seed germination tests of both L. dentata and T. vulgaris revealed a concentration-dependent reduction in their germination index (GI) at concentrations equal or above 2% v/v, apart from the effect of lavender extract on cress, where inhibition occurred at dose application above 5% v/v. In planta experiments demonstrated the complete phytoprotective action of lavender extract against F. oxysporum f.sp. radicis-lycopersici, while a marginal improvement in plant survival was observed during application of T. vulgaris extract. Full article

Plant defence elicitors have emerged as pivotal components of sustainable fruit crop protection, aligning with One Health principles by reducing chemical residues while enhancing ecosystem and human health. These exogenous agents—ranging from phytohormones, peptides, and cell-wall fragments to botanical extracts—activate or prime innate immune responses in fruit crops through pattern-triggered immunity (PTI), systemic acquired resistance (SAR), and induced systemic resistance (ISR) pathways. Over the last decade, advances in receptor biochemistry, genomics, metabolomics, and epigenetics have transformed this field. Recent mechanistic advances reveal that oligosaccharide elicitors derived from chitosan and laminarin are perceived by membrane-localised pattern recognition receptors (PRRs) that confer broad-spectrum resistance against fungal, bacterial, and viral pathogens in fruits. By contrast, no specific protein receptor has been identified for harpin proteins, the emerging evidence indicating that harpin perception may occur through direct interaction with plasma-membrane lipids or lipid-associated proteins. The One Health approach is supported by elicitors, biodegradability, minimal environmental persistence, and the ability to reduce synthetic fungicide usage by 30–70%. However, challenges remain regarding batch-to-batch variability, sensory acceptance due to bitter compounds, regulatory hurdles for novel food approvals, and the need for optimised application protocols that consider the fruit genotype and developmental stage. The future integration of nanotechnology for targeted delivery, the artificial-intelligence-driven screening of active molecules, and synergistic combinations with biocontrol agents promises to overcome these limitations, positioning plant defence elicitors as cornerstone tools for resilient, health-promoting fruit production systems. 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

Rice production experiences significant losses due to fungal diseases, particularly rice sheath blight caused by Rhizoctonia solani. Despite the intensive and continuous use of synthetic fungicides, diseases severity has not reduced and control has become increasingly challenging; therefore, the search for environmentally friendly and sustainable products has intensified. Here, we conducted a chemical characterization of Xylopia frutescens and using in silico analysis evaluated the interaction of their two major compounds with lectin protein site of R. solani. In vitro tests using increasing concentrations of essential oil against R. solani were performed. Subsequently, in four varieties of rice, five concentrations of X. frutescens essential oils were applied and evaluated the phytotoxicity effect as well the potential of Xylopia frutescens essential oil for controlling, both preventively and curatively, rice sheath blight. We further investigate the selectivity of this essential oil towards the non-target organism, Trichoderma asperellum. Our analysis revealed that trans-pinocarveol and myrtenal are the main compounds of X. frutescens essential oil and interact with the lectin of R. solani, supporting the antifungal properties of X. frutescens essential oil. In in vitro conditions, the highest tested concentrations of X. frutescens essential oil inhibited the pathogen’s sclerotia and mycelial growth. Under greenhouse conditions, the treatments caused low phytotoxicity and effectively reduced disease severity when applied, both preventively and curatively. Furthermore, the biocontrol agent T. asperellum exhibited tolerance to X. frutescens essential oil. Collectively, our findings demonstrate the potential of X. frutescens essential oil for the development of botanical fungicides capable of controlling R. solani without harming beneficial non-target organisms such as T. asperellum. Full article

Fungal diseases represent relevant constraints on global agricultural productivity, causing severe yield losses and deterioration of crop quality. The extensive use of chemical fungicides has produced environmental and health concerns due to their persistence, bioaccumulation, toxicity, and the increasing development of resistant fungal strains. To promote sustainable plant protection strategies, this study aimed to evaluate natural alternative products derived from botanical sources and agro-industrial wastes. Eighteen putative inhibiting products (PIPs), selected based on their availability as spontaneous plants or agro-industrial wastes, together with a commercial resistance inducer, were screened in in vitro assays against a collection of 31 phytopathogenic fungi. The inhibitory activity (IA) from the PIPs was evaluated, and statistical analyses were performed to identify the best performer. Several PIPs showed significant inhibitory activity against several fungal species, while others promoted fungal growth, highlighting the dual nature of the tested PIPs as potential bio-fungicides and growth-promoting agents for beneficial fungi. These findings highlight the value of plant-derived metabolites and agricultural waste valorization as promising sources for the development of sustainable botanical fungicides as well as support the transition toward eco-friendly crop protection strategies aligned with the European Green Deal objectives. Full article

Plant fungal diseases pose a serious threat to crop production and safety, and natural products are one of the important directions for the development of new green fungicides. This study found that the extract of Murraya euchristifolia had significant antifungal activity, and a main antifungal coumarin (1) was isolated by bioassay-guided fractionation. The structure of 1 was identified by NMR and MS spectroscopic data as a fused bis-furan coumarin (microminutinin) which was first isolated from the Murraya genus and exhibited strong broad-spectrum antifungal activity against eight plant pathogenic fungi from different families and genera. The EC₅₀ value of 1 (11.33 μg/mL) against Pestalotiopsis theae (the most sensitive to 1) was slightly higher than that (7.03 μg/mL) of the positive drug (80% carbendazim WP), indicating that 1 has the potential to serve as a lead compound for botanical fungicides. The bioassay results against P. theae in vivo indicated that 1 also has the potential for field application. Scanning electron microscopy and optical microscopy revealed that 1 disrupted the morphological structure of mycelium, causing hyphae to twist, shrink, and even crack and severely reducing hyphal branching. Furthermore, propidium iodide staining proved that microminutinin destroyed the integrity of the cell membrane, causing leakage of cellular components. In addition, calcofluor white staining and chitin content changes illustrated that microminutinin disrupted the cell wall structure. This research provides compound sources and a theoretical basis for the development of botanical fungicides. Full article

Background/Objectives: Skin wounds interrupt the natural anatomy and function of the skin. The body passes through four physiological phases to repair wounds after injury. Since the fibers are more closely related to the extracellular matrix structure, they can be used as scaffolds to accelerate wound closure. Shikonin is a botanical herbal remedy used as an anti-inflammatory agent and for its wound-healing characteristics. Cresols are known for their bactericidal and fungicidal properties, which promote their utilization as a disinfectant in soap. Therefore, this study aimed to formulate shikonin and cresol-loaded nanofibers for a dual wound-healing and antibacterial wound dressing in vitro. Methods: This study demonstrated the effectiveness of the drug-loaded nanofibers against diverse Gram-positive and Gram-negative bacteria using the minimum inhibitory concentration (MIC) and zone of inhibition assays. Results: Scanning electron microscopy images showed successful formulation of shikonin/cresol fibers with an average diameter of 772 ± 152 nm. The encapsulation efficiency and drug loading for the dual drug-loaded fibers were 44 ± 1% and 25 ± 1 µg/mg, respectively, for shikonin, and 38 ± 1% and 21 ± 0.5 µg/mg, respectively, for cresol, with a full release of both drugs achieved after 180 min. The combination of both compounds exhibited a safe concentration of ≤6 µg/mL, with cell viability of >50% in human dermal fibroblasts (HFF-1) after 24 h. The MIC results indicated that the combination was efficient as an antibacterial agent against Gram-positive bacteria at a safe concentration. The shikonin/cresol-loaded fibrous system showed an inhibition zone close to that of the control drugs, suggesting that the drugs have retained their antibacterial activity after electrospinning. Conclusions: This dual drug-loaded fiber system showed a high potential as an antibacterial wound dressing for skin infection injuries. However, in vivo studies are required to assess the safety and efficacy in an animal model of the dual drug-loaded fiber system. Full article

Neopestalotiopsis zimbabwana is an emerging phytopathogen with multiple hosts. Considering the environmental, toxicological, and resistance issues linked to synthetic fungicides, Origanum vulgare L. essential oil (OEO) was evaluated through in vitro, in vivo, and in silico approaches. The pathogen, isolated from Watsonia borbonica L., was molecularly identified. Gas chromatography–mass spectrometry (GC–MS) analysis showed hexadecanoic acid (15.98%), dodecanoic acid (15.74%), terpinen-4-ol (11.61%), and thymol (7.65%) as the main components. In vitro assays determined a minimum inhibitory concentration (MIC) of 30% OEO and a minimal fungicidal concentration (MFC) of 60% OEO. Growth chamber trials demonstrated that preventive sprays maintained 0% foliar damage—similar to Captan^®—while controls reached ≈98%; suspending applications after week 4 resulted in ≈45% damage by week 8. These results confirm that OEO lacks systemic residual activity, acting only as a protectant within preventive integrated pest management (IPM) schemes. Docking to cytochrome b (protein data bank, PDB: 5TL8) indicated strong binding of α-farnesene (−7.638 kcal·mol⁻¹), isoterpinolene (−6.944), and α-terpineol (−6.918), suggesting disruption of mitochondrial respiration via Complex III. OEO represents a promising eco-friendly alternative for managing N. zimbabwana under controlled conditions and reducing reliance on synthetic fungicides. Full article

Ball moss is an epiphytic, perennial monocot that attaches to many surfaces, including ornamental plants. Though not parasitic, ball moss can reduce the growth and health of host plants. Controlling ball moss has thus become necessary. Recommended methods include spraying baking soda or copper fungicide. This study was designed to validate the recommended methods and discover new, efficacious botanical ingredients in laboratory and field experiments. The efficacy of baking soda, but not the copper fungicide, was confirmed. However, baking soda blindly damages host plants and is not environmentally friendly. A screening study over several candidates (a monocot herbicide, eugenol, thymol, oleander extracts) selected eugenol from clove essential oil. In repeated laboratory studies, eugenol formulated into a soluble liquid (ESL) at 1% concentration achieved comparable lethal levels to 50% baking soda solution against ball moss. Efficacy was most apparent when applied in autumn. In the field trials, spraying ESL directly onto ball moss on live oak trees rather than broadcasting from the ground was efficacious. Possible mechanisms and limitations were discussed. Full article

Walnut anthracnose (Colletotrichum gloeosporioides and C. siamense) and brown spot (Alternaria alternata) cause severe yield losses globally. Conventional fungicides face the challenges of pathogen resistance and environmental toxicity. This study evaluates 4-propylphenol, a plant-derived phenolic compound, as an eco-friendly alternative against key fungal pathogens of walnut. In vitro assays determined EC₅₀ values against target pathogens (29.11–31.89 mg·L⁻¹) via mycelial growth inhibition and conidial germination suppression (EC₅₀ = 55.04–71.85 mg·L⁻¹). Mechanistic analyses confirmed membrane disruption through propidium iodide staining (9.5-to-14.0-fold fluorescence intensity increase), DNA leakage (77.82–85.15% at 250 mg·L⁻¹), and protein efflux (58.10–66.49%). In field trials, we implemented a phenology-driven strategy: 100 mg·L⁻¹ ground/canopy spray at flowering to reduce primary inoculum, followed by 400 mg·L⁻¹ canopy application at fruiting. This protocol achieved 86.67% control efficacy against disease complexes with negligible phytotoxicity (SPAD variation < 5%). 4-propylphenol provides a sustainable solution through membrane-targeting action, effectively overcoming fungicide resistance in woody crops. Full article

Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), threatens banana and plantain production throughout South America. Because Colombian biosafety regulations restrict in vitro work with Foc TR4, we tested the antifungal activity of Nostoc commune against F. oxysporum race 2 isolated from cv. ‘Manzano’ (Musa AAB). An ethanolic extract of the cyanobacterium (EEC) was profiled by gas chromatography and evaluated with a Kirby–Bauer assay (1000–4000 ppm; n = 4). Synthetic Sico^® and botanical Timorex^® served as positive controls, and solvent-free plates were the negative control. Growth reduction (GR) and percentage inhibition of radial growth (PIRG) were analysed with Student’s t-test (α = 0.05). Forty-two compounds—mainly fatty and carboxylic acids associated with antifungal activity—were detected. Sico achieved complete inhibition (100 ± 0%), Timorex suppressed 76 ± 2%, and 4 000 ppm EEC curtailed mycelial expansion by 45 ± 3% (p < 0.01). Although less potent than commercial fungicides, EEC impeded F. oxysporum growth, demonstrating that N. commune synthesises bioactive metabolites. Optimising cyanobacterial cultivation and formulation could yield a sustainable biocontrol alternative for managing Fusarium wilt in the region. Full article

Plant-derived biopesticides are emerging as a promising and popular alternative for promoting cleaner and safer agricultural practices. The present work aims to explore Argyranthemum frutescens (Asteraceae) as a source of botanical pesticides and to validate this through a cultivation process. To this task, a bioassay-guided fractionation of the ethanolic root extracts from both wild and cultivated A. frutescens on phytopathogenic fungi of Botrytis cinerea, Fusarium oxysporum, and Alternaria alternata was conducted. This approach led to the identification of polyacetylenes with higher potency than commercial fungicides. Specifically, compounds 3 (capillin) and 5 (frutescinone) showed more than 90% growth inhibition at 0.05 mg/mL concentration on B. cinerea, while compounds 2 (capillinol) and 3 were also more active than positive controls, Fosbel-Plus and Azoxystrobin, against F. oxysporum. The structures of the isolated polyacetylenes (1–6, 9, and 10) and alkamides (7, 8, and 11) were determined through spectroscopic analysis, and the absolute configuration of stereocenter C1 of compounds 1, 2, 4 and 9 was determined by NMR-spectroscopy with (R)-(-)-α-methoxy-phenylacetic as a chiral derivatizing agent, and biogenetic considerations. Overall, this study supports the potential of polyacetylenes as promising agrochemical lead compounds against phytopathogens, and validates A. frutescens cultivation as a viable source of biopesticides. Full article

Botanical extracts are being considered for integration into disease management programs to control plant pathogenic fungi and oomycetes. A promising extract with potential is the essential oil of Lippia graveolens. However, its extraction process has not been optimized. Since optimizing process conditions can impact fungicidal and/or oomyceticidal effects, this research implemented time, temperature, and solid/liquid ratio conditions to maximize the fungicidal and oomyceticidal effects. The effectiveness was evaluated through parameters of mycelial growth inhibition, spore germination inhibition, minimum inhibitory and fungicidal/oomyceticidal concentration for the fungi Gilbertella persicaria, Agroathelia rolfsii, and Colletotrichum gloeosporioides, as well as the oomycete Phytophthora capsici. Optimal conditions were as follows: time: 46.27 min; temperature: 329.34 °C; and solid/liquid ratio: 80.35 g/L. In general, the optimized treatment was more effective in A. rolfsii ≥ P. capsica > G. persicaria ≥ C. gloeosporioides in all assays. These results demonstrate the fungicidal and oomiceticidal effects of L. graveolens essential oil, with potential for commercial product formulation. Full article

Considering the detrimental impacts of the current pesticides on the biotic components of the biosphere, the development of novel pesticides is vital. Plant-derived biopesticides have emerged as popular alternatives to create a safer and more sustainable agriculture model. This study aims to validate the previous bioguided fractionation of endemic Canary Islands sage, Salvia canariensis, as a potential source of botanical pesticides using a cultivation process. Accordingly, the bioassay-guided fractionation of the ethanolic extract of the leaves of cultivated S. canariensis on the phytopathogenic fungal mycelia of Botrytis cinerea, Fusarium oxysporum, and Alternaria alternata yielded six known terpenoids. Their abietane diterpenoid-type (1–5) and sesquiterpenoid (6) structures were established based on spectroscopic and spectrometric analysis. This strategy identified one abietane diterpenoid, salviol (5), as a potential candidate for the future development of biofungicides with similar potency towards the assayed phytopathogenic fungi to commercial fungicides. Salviol worked in a concentration-dependent manner. Overall, this study reinforces the potential of abietane-type diterpenoids as promising agrochemical lead compounds against infectious diseases caused by phytopathogenic fungi and validates the cultivation of S. canariensis as a potential source of plant-derived biopesticides. Full article