RESUMEN
AIMS: The efficacy of three isolates of endophytic Penicillium species that have shown significant suppressive effect on root rotting fungi in our previous study were further evaluated in pots and field plot experiments for their effect on root diseases of okra, induction of systemic resistance and physiochemical properties of okra fruit. METHODS AND RESULTS: Aqueous suspensions of endophytic Penicillium and Pseudomonas monteilii were applied in pots and field plots using okra as test plant. Data on the fungal infection of roots, plant growth, plant resistance markers like polyphenol, salicylic acid and antioxidant status of plant were determined. These isolates significantly suppressed root diseases and induced systemic resistance via increasing level of resistance markers, polyphenol and salicylic acid besides improving antioxidant activity of Penicillium and P. monteilii-treated plants as compared to control plants. GC-MS analysis of n-hexane extract of mycelium of P. nigricans revealed the presence of 15 different volatile compounds. CONCLUSIONS: Endophytic Penicillium and P. monteilii have potential against root-infecting fungi of okra and can improve plant growth and yield. SIGNIFICANCE AND IMPACT OF THE STUDY: Endophytic Penicillium species and P. monteilii can suppress root rotting fungi by direct mechanism or induction of systemic resistance in plants.
Asunto(s)
Abelmoschus/microbiología , Resistencia a la Enfermedad , Endófitos/fisiología , Penicillium/fisiología , Pseudomonas/fisiología , Abelmoschus/crecimiento & desarrollo , Abelmoschus/inmunología , Endófitos/química , Endófitos/aislamiento & purificación , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Frutas/microbiología , Penicillium/química , Penicillium/aislamiento & purificación , Fitoquímicos/metabolismo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/prevención & control , Raíces de Plantas/microbiología , Pseudomonas/química , Pseudomonas/aislamiento & purificación , Compuestos Orgánicos Volátiles/análisisRESUMEN
Temporomandibular joint (TMJ) disorders show inflammatory components, heavily impacting on quality of life. Abelmoschus esculentus is largely cultivated in Northeastern Brazil for medicinal purposes, having it shown anti-inflammatory activity. We evaluated A. esculentus lectin (AEL) efficacy in reducing zymosan-induced temporomandibular joint inflammatory hypernociception in rats along with the mechanism of action through which it exerts anti-inflammatory activity. Animals were pre-treated with AEL (0.01, 0.1 or 1mg/kg) before zymosan (Zy) injection in the TMJ to determine anti-inflammatory activity. To analyse the possible effect of the hemeoxygenase-1 (HO-1) and the nitric oxide (NO) pathways on AEL efficacy, animals were pre-treated with ZnPP-IX (3mg/kg), a specific HO-1 inhibitor, or aminoguanidine (30mg/kg), a selective iNOS inhibitor, before AEL administration. Von Frey test evaluated inflammatory hypernociception, synovial fluid collection was performed to determine leukocyte counting and myeloperoxidase (MPO) activity 6h after Zy injection, and Evans Blue extravasation determined vascular permeability. TMJ tissue was collected for histopathological analysis (H&E) and immunohistochemistry (TNF-α, IL-1ß, HO-1). In addition, TMJ tissue and trigeminal ganglion collection was performed for TNF-α and IL-1ß dosage (ELISA). AEL increased inflammatory nociceptive threshold, reduced leukocyte influx along with MPO activity, leukocyte influx into the synovial membrane, and Evans Blue extravasation. It promoted HO-1 overexpression whilst decreased TNF-α and IL-1ß expression in the TMJ tissue. AEL reduced TNF-α and IL-1ß levels in TMJ tissue and trigeminal ganglion. AEL effects, however, were not observed in the presence of ZnPP-IX. These findings suggest that AEL efficacy depends on TNF-α/IL-1ß inhibition and HO-1 pathway integrity.