Chemometrics applied to 1H NMR and UV-Vis spectroscopy as a way to evaluate solid-liquid extraction of leaves of artichoke.

Artichoke has several biological actions, which are related to the synergistic action of its bioactive compounds. Solid-liquid extraction influence the type and quantity of compounds extracted and, consequently, the biological activity of the plant extract. This study aims to investigate which extraction method (maceration, infusion, or Soxhlet) and which green solvent (ethanol or acetone) would be more suitable to obtain bioactive artichoke extracts. All solid-liquid procedures were carried out in triplicate, using 3.0 g of artichoke leaves and 200 mL of solvent. After drying, samples were analyzed by UV-Vis and 1H NMR. Chemometrics was applied to spectroscopic data, and the PCA analysis showed that they were specially separated according to the solvent extractor. The sesquiterpene lactone cynaropicrin was identified as the major compound of the extracts, and this allowed us to conclude that the best solid-liquid procedure was Soxhlet, using ethanol as solvent.

Liquid Fungal Cocultivation as a Strategy to Access Bioactive Metabolites.

Fungi are a rich source of bioactive compounds. Fungal cocultivation is a method of potentiating chemical interactions and, consequently, increasing bioactive molecule production. In this study, we evaluated the bactericidal, antiprotozoal, and cathepsin V inhibition activities of extracts from axenic cultures of 6 fungi (Fusarium guttiforme, Pestalotiopsis diospyri, Phoma caricae-papayae, Colletotrichum horii, Phytophthora palmivora, and C. gloeosporioides) that infest tropical fruits and 57 extracts obtained by their cocultivation. Our results reveal that fungal cocultivation enhances the biological activity of the samples, since all extracts that were active on Gram-positive bacteria, Gram-negative bacteria, Trypanosoma cruzi, and Leishmania infantum were obtained from cocultivation. Bacterial growth is either totally or partially inhibited by 46% of the extracts. Two extracts containing mainly fusaric and 9,10-dehydrofusaric acids were particularly active. The presence of the fungus F. guttiforme in co-cultures that give rise to extracts with the highest activities against L. infantum. An axenic culture gave rise to the most active extract for the inhibition of cathepsin V; however, other coculture extracts also exhibited activity toward this biological target. Therefore, the results of the biological activities indicate that fungal cocultivation increased the biological potential of samples, likely due to the hostile and competitive environment that pushes microorganisms to produce substances important for defense and allows access to metabolic routes then silenced in milder cultivation conditions.

Evaluation of biodiesel-diesel blends quality using 1H NMR and chemometrics.

In this work, the use of (1)H NMR spectroscopy and statistical approach to the evaluation of biodiesel-diesel blends quality is described. Forty-six mixtures of oil-diesel, biodiesel-diesel, and oil-biodiesel-diesel were analyzed by (1)H NMR and such data were employed to design four predictive models. Thirty-six mixtures were used in the calibration set and the others in the validation. The PCR and PLS models were evaluated through statistical parameters. Briefly, PLS and PCR models were suitable for the prediction of biodiesel and oil concentration in mineral diesel. Specially, in higher concentration the predicted values were quite similar to the real ones. This fact was evidenced by the low relative errors of high concentrated samples; this means that the prediction of low concentrated samples will probably show high deviation. Therefore, (1)H NMR-PLS and (1)H NMR-PCR methods are fairly useful for the quality control of biodiesel-diesel blends, particularly they are suitable for prediction of concentrations greater than 2%.

Trypanocidal activity of limonoids and triterpenes from Cedrela fissilis.

Chagas' disease is an illness that affects millions of people in Central and South America. The search for both a prophylactic drug to be added to human blood as well as a safe and reliable therapeutic drug are greatly needed to control such disease. Herein, we report the trypanocidal activity of 15 crude extracts and 14 compounds (limonoids and triterpenes) as well as the isolation of 25 known compounds (6 limonoids, 12 triterpenes, 1 sesquiterpene, 5 steroids, and 1 flavonoid) from Cedrela fissilis. The present study shows that this plant is a promising source of active compounds for the control of Chagas' disease. The inhibitory activity found for odoratol indicates that it is potentially useful as an alternative for the chemoprophylactic gentian violet.

Trypanocidal activity of Meliaceae and Rutaceae plant extracts.

The in vitro trypanocidal activity of 22 extracts and 43 fractions of plants belonging to the families Meliaceae and Rutaceae was evaluated. The extracts from leaves of Conchocarphus heterophyllus and branches of Trichilia ramalhoi were the most active. The trypanocidal activity seems to be increased by fractionation of the extracts. Fractions from C. heterophyllus and Galipea carinata were the most active and a 100% lysis of the parasites was observed for five fractions. From one of them were isolated two flavonoids: flavone and 7-methoxyflavone, which showed weak trypanocidal activity. The results obtained from the extracts and fractions revealed that the order Rutales is a promising source for the search of new drugs for Chagas disease. Phytochemical studies with the other active fractions are underway in order to isolate compounds, which could be associated with observed activities.

Trypanocidal activity of Meliaceae and Rutaceae plant extracts

The in vitro trypanocidal activity of 22 extracts and 43 fractions of plants belonging to the families Meliaceae and Rutaceae was evaluated. The extracts from leaves of Conchocarphus heterophyllus and branches of Trichilia ramalhoi were the most active. The trypanocidal activity seems to be increased by fractionation of the extracts. Fractions from C. heterophyllus and Galipea carinata were the most active and a 100 percent lysis of the parasites was observed for five fractions. From one of them were isolated two flavonoids: flavone and 7-methoxyflavone, which showed weak trypanocidal activity. The results obtained from the extracts and fractions revealed that the order Rutales is a promising source for the search of new drugs for Chagas disease. Phytochemical studies with the other active fractions are underway in order to isolate compounds, which could be associated with observed activities.