No abstract

We investigated the effects of fire on the secondary metabolites of Rhamnidium elaeocarpum in the Pantanal region. We analyzed the total phenol and tannin content of individuals from four different sampling groups and used LC-MS metabolomics techniques to observe the metabolites present in the samples and the thermogravimetric behavior of the species. Our findings suggest that recent fires did not significantly affect the species' phenolic metabolism, except for specimens affected by the 2020 megafire, which exhibited a decline in compounds due to leaching. The data suggests that recent fire incidents did not impact the phenolic metabolism of the species, and the high levels indicate that the species has a biochemical tolerance to the stress caused by seasonal fires. Metabolomic profiles showed intense biosynthesis of proanthocyanidin oligomers, which protect against oxidative stress and post-fire environmental disturbances. The results of the thermogravimetric behavior showed the species' thermotolerance and intrinsic relationship with secondary compounds. Overall, our study advanced our understanding of the impact of fire on woody species' metabolism. However, distinguishing whether chemical traits are an adaptive feature or a response to surrounding environmental factors presents a challenge.

We conducted a study on the effects of fire on Rhamnidium elaeocarpum, a widely distributed woody species found in the Pantanal wetlands, using LC–MS metabolomics, total phenolic and tannin content analysis, and thermogravimetric behavior. We sampled individuals from four groups: No Fire, Fire 2019, Fire 2020, and APD 20 (individuals whose aerial parts had died during the 2020 fire event). We found that recent fires had no significant impact on the species' phenolic metabolism except for those in the fourth group. These specimens showed a decline in secondary metabolites due to leaching. The high levels of phenolics in R. elaeocarpum suggest that this species has a biochemical tolerance to the stress caused by seasonal fires. Metabolomic profiling revealed the presence of proanthocyanidin oligomers, which protect against oxidative stress and post-fire environmental disturbances. However, the passage of fire also led to a high incidence of toxic karwinaphthopyranone derivatives, which could be a concern for the species' medicinal use. Finally, the thermogravimetric analysis showed that the species is thermotolerant, with an intrinsic relationship between the secondary compounds and thermotolerance. Our research has deepened the comprehension of how fire affects the metabolic processes of woody plants. The challenge now lies in determining if the identified chemical changes are adaptive characteristics that evolved over time or merely transient responses to external environmental stimuli.

We conducted a study on the effects of fire on Rhamnidium elaeocarpum, a widely distributed woody species found in the Pantanal wetlands, using LC-MS metabolomics, total phenolic and tannin content analysis, and thermogravimetric behavior. We sampled individuals from four different groups and found that recent fires had no significant impact on the species' phenolic metabolism, except for those specimens whose aerial parts had died during the 2020 megafire, which showed a compound decline due to leaching. The high levels of phenolics in R. elaeocarpum suggest that the species has a biochemical tolerance to the stress caused by seasonal fires. Metabolomic profiling revealed the presence of proanthocyanidin oligomers, which protect against oxidative stress and post-fire environmental disturbances. However, the passage of fire also led to a high incidence of toxic karwinaphthopyranone derivatives, which could be a concern for the species' medicinal use. Finally, the thermogravimetric analysis showed that the species is thermotolerant, with an intrinsic relationship between the secondary compounds and thermotolerance. Our study enhances our understanding of the impact of fire on woody species' metabolism, although distinguishing whether chemical traits are an adaptive feature or a response to surrounding environmental factors is challenging.