Saponin Detoxification by Plant Pathogenic Fungi
Saponins are common plant secondary metabolites (glycosylated triterpenoid or steroid molecules) which are found in a wide range of dicotyledonous plant species, and also in some monocots1–5. Many saponins have been demonstrated to have potent antifungal activities and often occur in healthy plants at levels which are anticipated to be toxic to saponin-sensitive fungi6. This has led to speculation that saponins may act as pre-formed determinants of resistance to fungal attack. Van Etten et al.7 have proposed the term “phytoanticipin” to distinguish pre-formed antimicrobial substances from those induced de novo in response to pathogen attack (phytoalexins). By this definition saponins fall into the category of phytoanticipins. However, in some instances the concentrations of saponins have been reported to increase in response to microbial attack8,9.
KeywordsGlycosyl Hydrolase Triterpenoid Saponin Target Gene Disruption Potent Antifungal Activity Steroidal Glycoalkaloid
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