Erythrina velutina Willd. alkaloids: Piecing biosynthesis together from transcriptome analysis and metabolite profiling of seeds and leaves

Introduction: Natural products of pharmaceutical interest often do not reach the drug market due to the associated low yields and difficult extraction. Knowledge of biosynthetic pathways is a key element in the development of biotechnological strategies for plant specialized metabolite production. The scarce studies regarding non-model plants impair advances in this field. Erythrina spp. are mainly used as central nervous system depressants in folk medicine and are important sources of bioactive tetracyclic benzylisoquinoline alkaloids, which can act on several pathology-related biological targets. Objective: Herein the purpose is to employ combined transcriptome and metabolome analyses (seeds and leaves) of a non-model medicinal Fabaceae species grown in its unique arid natural habitat. The study tries to propose a putative biosynthetic pathway for the bioactive alkaloids by using an omic integrated approach. Methods: The Next Generation Sequencing-based transcriptome (de novo RNA sequencing) was carried out in a Illumina NextSeq 500 platform. Regarding the targeted metabolite profiling, Nuclear Magnetic Resonance and the High-Performance Liquid Chromatography coupled to a micrOTOF-QII, High Resolution Mass Spectrometer, were used. Results: This detailed macro and micromolecular approach applied to seeds and leaves of E. velutina revealed 42 alkaloids by metabolome tools. Based on the combined evidence, 24 gene candidates were put together in a putative pathway leading to the singular alkaloid diversity of this species. Conclusion: These results contribute by indicating potential biotechnological targets Erythrina alkaloids biosynthesis as well as to improve molecular databases with omic data from a non-model medicinal plant. Furthermore, they reveal an interesting chemical diversity in Erythrina velutina harvested in Caatinga. Last, but not least, this data may also contribute to tap Brazilian biodiversity in a rational and sustainable fashion, promoting adequate public policies for preservation and protection of sensitive areas within the Caatinga

Isoflavone production in hairy root cultures and plantlets of Trifolium pratense

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Análise de metais pesados em amostras de peumus boldus mol. (monimiaceae)

Oito amostras, provenientes do Brasil, Chile e Argentina, de Peumus boldus Molina (Monimiaceae), espécie comum e abundante no Chile, cujas folhas são amplamente empregadas pela medicina tradicional para o tratamento de uma variedade de afecções do sistema digestivo e hepatobiliar, foram analisadas, após digestão nítrica, para a quantifi cação de ferro, manganês, cobre, chumbo, cromo, cobalto e níquel, por espectrofotometria de absorção atômica. Chumbo, cromo e cobalto não foram detectados (limite de detecção de 5 µg/g) em nenhuma das amostras. Todas as amostras apresentaram maior teor em ferro, que variou de 109,7 mg/kg a 315,7 mg/kg, seguido por manganês (65,5 mg/kg a 158,8 mg/kg), cobre (3,04 mg/kg a 9,16 mg/kg) e níquel (0,77 mg/kg a 4,31 mg/kg).Eight samples, obtained from Brazil, Chile and Argentina, of Peumus boldus Molina (Monimiaceae), an abundant and widespread native tree in Chile, which leaves are widely used in folk medicine for the treatment of digestive and hepatobiliary disorders, were analyzed, after nitric digestion, for the content of iron, manganese, copper, lead, chromium, cobalt and nickel, by atomic absorption spectrophotometry. Lead, chromium and cobalt were not detected (detection limit of 5 µg/g) in any sample. The samples showed a high level of iron, which ranged from 109.7 mg/kg to 315.7 mg/kg, followed by manganese (65.5 mg/kg to 158.8 mg/kg), copper (3.04 mg/ kg to 9.16 mg/kg) and nickel (0.77 mg/kg to 4.31 mg/kg)

Root exudation of oxalic acid in Lotus corniculatus in response to aluminum toxicity

The objective of this research was to identify the existence of root exudation of organic acid in Lotus corniculatus germplasms subjected to toxic aluminum (Al) levels and investigate the effect of this mechanism on the Al content in the root tissue and in morphological parameters of plant development. Two experiments were performed in nutrient solution to evaluate the Al accumulation and exudation of organic acids, using cultivars INIA Draco and São Gabriel and genotypes UFRGS and UF-T2. The plants were cultivated in Al-free solution, which was applied on the 45th day in half of the pots of each genotype. Root exudation was highly correlated with the reduced accumulation of Al in the root tissue (r2 = 0.75 at 72 h). Genotype UF-T2, selected for Al tolerance, extruded 80% more oxalic acid in the presence of Al compared with the other germplasms, indicating that this mechanism is involved with Al tolerance in L. corniculatus. This experiment showed strong evidence that L. corniculatus exhibits Type I tolerance, in which anionic channels are rapidly activated by Al exposure. Exudation of oxalic acid is likely a crucial mechanism that allows the maintenance of L. corniculatus growth when exposed to toxic Al conditions, and this characteristic should be used to identify tolerant genotypes in the futur