Chitosan-induced production of secondary metabolites in plant extracts of Piper auritum, and the in vitro fungicidal activity against Fusarium oxysporum f. sp. vanillae

Abstract

<p>Se probó el efecto del quitosano sobre la producción de metabolitos secundarios de extractos etanólicos de <em>Piper auritum</em>, así como la actividad fungicida<em> in vitro</em> contra<em> Fusarium oxysporum</em> f. sp. <em>vanillae</em>. Las plantas de <em>P. auritum</em> se dividieron en seis parcelas y se añadió quitosano comercial a la mitad de ellas. Se midieron las concentraciones de flavonoides, fenoles, terpenos, alcaloides y ácido salicílico en extractos etanólicos de <em>P. auritum</em> y la actividad antifúngica se midió con la concentración efectiva media (CE50). Las concentraciones totales de flavonoides, fenoles y terpenos fueron más altas con el tratamiento con quitosano (sin quitosano 12.8 versus con quitosano 12.4 ?g equivalente de quercetina por mg, 12.6 versus 2.3 ?g equivalente de ácido tánico por 10 mg y 16.3 versus 11.6 mg equivalente de mentol por 100 mg). Mientras que la concentración de alcaloides disminuyó mediante la adición de quitosano (de 148.2 a 84.5 ?g de equivalente de piperina por mg). La adición de quitosano aumentó la concentración de ácido salicílico (de 1.3 a 2.2 ?g de equivalente de ácido salicílico por mg). La concentración de 4 mg mL-1 de extracto etanólico de <em>P. auritum</em> tratado con quitosano inhibió el 100% del crecimiento micelial. El tratamiento con quitosano generó que la CE50 de <em>P. auritum</em> contra <em>F. oxysporum</em> f. sp. <em>vanillae</em> fuera menor (1.5 mg mL-1) respecto al control (5.1 mg mL-1). Se concluye que la adición de quitosano aumentó la producción de metabolitos secundarios y la actividad antifúngica <em>in vitro</em> en extractos de <em>P. auritum.</em></p>

1H‐NMR Metabolomics Profiling and Volatile Content of ‘Hoja Santa’ (Piper auritum Kunth): A Millenary Edible Plant Consumed in Mexico

“…The identification of oil metabolites was carried out by direct analysis in real time mass spectrometry (DART‐MS) [25] . Interestingly, the concentrations of total flavonoids, phenols and terpenes were higher with chitosan treatment in a wild population of P. auritum selected in the locality of San Andrés Tlalnelhuayocan, Veracruz, Mexico (19°33′58“ N, 96°58′23” O, 1664 masl) [26] . However, the alkaloid concentration was reduced by chitosan addition [26] .…”

“…[25] Interestingly, the concentrations of total flavonoids, phenols and terpenes were higher with chitosan treatment in a wild population of P. auritum selected in the locality of San Andrés Tlalnelhuayocan, Veracruz, Mexico (19°33'58" N, 96°58'23" O, 1664 masl). [26] However, the alkaloid concentration was reduced by chitosan addition. [26] The insecticidal effect of the essential oils from P. auritum was demonstrated by the susceptibility of males and females of Drosophila suzukii Matsumura (Diptera: Drosophilidae) to volatile compounds of Thymus vulgaris and P. auritum at different concentrations after 1, 4, and 24 h postapplication.…”

“…[26] However, the alkaloid concentration was reduced by chitosan addition. [26] The insecticidal effect of the essential oils from P. auritum was demonstrated by the susceptibility of males and females of Drosophila suzukii Matsumura (Diptera: Drosophilidae) to volatile compounds of Thymus vulgaris and P. auritum at different concentrations after 1, 4, and 24 h postapplication. Oils from both plants made evident their high toxicity to D. suzukii males and females.…”

Chitosan in the protection of agricultural crops against phytopathogens agents

“…33,66 It also increases the synthesis of secondary metabolites associated with defense against damage and plant diseases such as phytoalexins, 16,68,69 catalases, polyphenoloxidases, 70 flavonoid-type phenolics and terpenes. 69,71 Chitosan stimulates the generation of phenylalanine ammonialyase, a fundamental enzyme to initiate the plant response against the attack of pathogens of the Fusarium sp type and other phytopathogens 66,68,71 by increasing the synthesis of salicylic acid, better plant growth is induced. 71 In addition, it regulates the levels of reactive oxygen species (ROS) related to oxidative stress that leads to cell aging and apoptosis in response to the negative action of environmental and biological factors against plant health.…”

“…69,71 Chitosan stimulates the generation of phenylalanine ammonialyase, a fundamental enzyme to initiate the plant response against the attack of pathogens of the Fusarium sp type and other phytopathogens 66,68,71 by increasing the synthesis of salicylic acid, better plant growth is induced. 71 In addition, it regulates the levels of reactive oxygen species (ROS) related to oxidative stress that leads to cell aging and apoptosis in response to the negative action of environmental and biological factors against plant health. 59 Chitosan increases the formation of callose, a sugar that is released when the plant suffers biological damage such as phytopathogens or mechanical damage, 58 for the lignification of the cell wall, 66-68 also, in the formation of papillae and tyloses that prevent endophytic phytopathogenic agents from penetrating the interior of the plant.…”