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Jatropha curcas is a promising non-food source of oil for biodiesel. However, the presence of phorbol esters (PE) is the main limiting factor for utilization of defatted cakes for animal feed. Reliable methods of analysis and quantification of phorbol esters are useful for plant breeding research as well as for detoxification process. Analytical methods for PE extraction show different conditions, temperatures, contact times, solvents and mass/solvent ratio. In this work, methanol and dichloromethane were evaluated as extraction solvent, and Soxhlet, ultrasound and stirring assisted extractions at different times of contact were compared. The quantification was performed by HPLC-DAD. Methanol was more efficient for exhaustive J. curcas PE extraction as compared to dichloromethane. Among the evaluated extraction methods, Soxhlet extraction with methanol during 6 h was the most efficient to quantify PE, showing RSD (Relative Standard Deviation) varying from 3 to 5%. The validated method showed limits of detection and quantification of 0.48 and 1.4 μg, respectively, with good linearity and precision. The specificity of the method was confirmed by LC–MS/MS and UV spectra data using three different columns and mobile phases.

International audience; This report describes the isolation and characterization of kalanchosine dimalate (KMC), an anti-inflammatory salt from the fresh juice of the aerial parts of Kalanchoe brasiliensis. KMC comprises the new metabolite kalanchosine (1) and malic acid (2) in a 1:2 stoichiometric ratio. Kalanchosine (1), 3,6-diamino-4,5-dihydroxyoctanedioic acid, is the first naturally occurring dimeric bis(γ-hydroxy-β-amino acid) and is at least partially responsible for the anti-inflammatory properties of K. brasiliensis. © 2006 American Chemical Society and American Society of Pharmacognosy.

Background: Brazil nut is a protein-rich extractivist tree crop in the Amazon region. Fungal contamination of shells and kernel material frequently includes the presence of aflatoxigenic Aspergillus species from the section Flavi. Aflatoxins are polyketide secondary metabolites, which are hepatotoxic carcinogens in mammals. The objectives of this study were to identify Aspergillus species occurring on Brazil nut grown in different states in the Brazilian Amazon region and develop a specific PCR method for collective identification of member species of the genus Aspergillus. Results: Polyphasic identification of 137 Aspergillus strains isolated from Brazil nut shell material from cooperatives across the Brazilian Amazon states of Acre, Amapá and Amazonas revealed five species, with Aspergillus section Flavi species A. nomius and A. flavus the most abundant. PCR primers ASP_GEN_MTSSU_F1 and ASP_GEN_MTSSU_R1 were designed for the genus Aspergillus, targeting a portion of the mitochondrial small subunit ribosomal RNA gene. Primer specificity was validated through both electronic PCR against target gene sequences at Genbank and in PCR reactions against DNA from Aspergillus species and other fungal genera common on Brazil nut. Collective differentiation of the observed section Flavi species A. flavus, A. nomius and A. tamarii from other Aspergillus species was possible on the basis of RFLP polymorphism. Conclusions: Given the abundance of Aspergillus section Flavi species A. nomius and A. flavus observed on Brazil nut, and associated risk of mycotoxin accumulation, simple identification methods for such mycotoxigenic species are of importance for Hazard Analysis Critical Control Point system implementation. The assay for the genus Aspergillus represents progress towards specific PCR identification and detection of mycotoxigenic species.