Concerns about the ecological and health risks of indiscriminate use of pesticides have increased interest in natural alternatives that are less harmful yet still effective. Resilient species from harsh environments are a valuable source of active compounds. However, intra-species chemical variability resulting from the interaction between their local growing condition and the developmental stage is often underestimated but relevant for defining superior raw materials. Azorella prolifera, a widely dominant species in arid and semiarid areas of South America, is a valuable model for addressing this purpose. This study aimed to carry out a spatiotemporal characterization of bioactive metabolite profiling of A. prolifera , considering different provenances and phenological stages of the plant material. The antifungal activities of the A. prolifera essential oils and hydrolats against 9 plant fungal pathogens were also assessed. This species exhibited an enriched secondary metabolic profile, containing at least 31 (poly)phenols (4.1 ± 1.4 g/100 g of dry weight) and up to 55 volatiles. A. prolifera essential oils showed a promising performance against Fusarium graminearum (a devastating crop disease), with minimum inhibitor and fungicide concentrations between 250-500 μg/mL . Variability in chemical profiling and antifungal effectiveness within this species was revealed. Natural populations from 41°08'S - 71°08'W provide extra value due to their hydrolats exhibit fungistatic activity against A. fumigatus and B. cinerea fungi. Our results reveal the potential of A. prolifera for biofungicide formulation and demonstrate the relevance of spatiotemporal chemical screening of raw material in order to identify superior ones.
Mattera et al. (Wed,) studied this question.