ABSTRACT
Wheat is a highly relevant crop worldwide, and like other massive crops, it is susceptible to foliar diseases, which can cause devastating losses. The current strategies to counteract wheat diseases include global monitoring of pathogens, developing resistant genetic varieties, and agrochemical applications upon diseases' appearance. However, the suitability of these strategies is far from permanent, so other alternatives based on the stimulation of the plants' systemic responses are being explored. Plants' defense mechanisms can be elicited in response to the perception of molecules mimicking the signals triggered upon the attack of phytopathogens, such as the release of plant and fungal cell wall-derived oligomers, including pectin and chitin derivatives, respectively. Among the most studied cell wall-derived bioelicitors, oligogalacturonides and oligochitosans have received considerable attention in recent years due to their ability to trigger defense responses and enhance the synthesis of antipathogenic compounds in plants. Particularly, in wheat, the application of bioelicitors induces lignification and accumulation of polyphenolic compounds and increases the gene expression of pathogenesis-related proteins, which together reduce the severity of fungal infections. Therefore, exploring the use of cell wall-derived elicitors, known as oligosaccharins, stands as an attractive option for the management of crop diseases by improving plant readiness for responding promptly to potential infections. This review explores the potential of plant- and fungal-derived oligosaccharins as a practical means to be implemented in wheat crops.
ABSTRACT
Chitin and chitosan are a class of metabolites that occurring in some fungi species that are associated with commercial and medicinal plants, this is in Mucor sp. for example with an ample number of biological activities, being antibacterial and antifungal one of the most important. Into our program of search of biopesticides and natural compounds with biological activities, we have studying chitosan that was obtained from the culture medium of the fungus Mucor ruoxii. Chitooligosaccharides were prepared by partial acid hydrolysis of native chitosan and an aminoglycosylated derivative was obtained by reductive amination of the chitooligosaccaride. The solubilities of these compounds were measured at different pHs and its antibacterial activity against Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive). Chitosan and the derivatives tested exhibited a good antibacterial activity against S. aureus.
Quitina y quitosano son una clase de metabolitos que producen algunas especies de hongos que están asociados con plantas medicinales y comerciales, esto es por ejemplo en Mucor sp., con un amplio número de actividades biológicas, siendo la antibacteriana y antifúngica unas de las más importantes. En nuestro programa de investigación de biopesticidas y compuestos naturales, estamos estudiando quitosano obtenido de el medio de cultivo del hongo Mucor ruoxii. Quitooligosacáridos fueron preparados por hidrólisis parcial ácida de quitosano nativo y un derivado aminoglicosilado fue obtenido por aminación reductiva del quitooligosacárido. Las solubilidades de estos compuestos fueron medidas a diferentes pHs y su actividad antibacteriana frente a Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive). Quitosano y los derivados testeados exhiben una buena actividad antibacteriana frente a S. aureus.