The drug-resistance of malaria parasites is the main problem in the disease control. The huge Brazilian biodiversity promotes the search for new compounds, where the animal kingdom is proving to be a promising source of bioactive compounds. The main objective of this study was to evaluate the antiplasmodial and cytotoxic activity of the compounds obtained from the toad venoms of Brazilian Amazon. Toad venoms were collected from the secretion of Rhinella marina and Rhaebo guttatus in Mato Grosso State, Brazil. The powder was extracted at room temperature, yielding 2 extracts (RG and RM) and a substance ('1') identified as a bufadienolide, named telocinobufagin. Growth inhibition, intraerythrocytic development, and parasite morphology were evaluated in culture by microscopic observations of Giemsa-stained thin blood films. Cytotoxicity was determined against HepG2 and BGM cells by MTT and neutral red assays. The 2 extracts and the pure substance ('1') tested were active against chloroquine-resistant Plasmodium falciparum strain, demonstrating lower IC50 values. In cytotoxic tests, the 2 extracts and substance '1' showed pronounced lethal effects on chloroquine-resistant P. faciparum strain and low cytotoxic effect, highlighting toad parotoid gland secretions as a promising source of novel lead antiplasmodial compounds.

The total phenol concentration present in Vochysia divergens Pohl. (Vochysiaceae) leaves in the Pantanal was analyzed. Work was carried out between September/2012 and June/2013 which is made up by the dry season (September/2012), the beginning of the rising water (December/2012), the high water (March/2013) followed by the receding water period (June/2013). For the purpose of the research fifteen trees were selected, five from each sample area. The phenolic content in the leaves was obtained from the samples which were dried, steeped with ethanol: water and centrifuged. The extract was used to determine the concentration of total phenols using the Folin-Ciocalteu spectrometric method. There was no difference among the sampling areas; however the values were different in relation to seasonal periods. The lowest concentration was recorded in the dry season (young leaves) increasing gradually at the beginning of the rising water, with higher levels at the end of high water and receding water season. The highest concentration of phenols occurred during the receding water period (end of the life cycle of V. divergens leaves), followed by high and rising water periods. The increase in phenol concentration is associated with the Pantanal flood cycle, and related to the phenology of the V. divergens leaves.

Species of the genus Cordia have shown biological activities, such as anti-inflammatory, analgesic, antioxidant, antiviral, and antifungal activities. The species Cordia glabrata (MART) A.DC. Has no information concerning its phytochemical profile and possible biological activities. Thus, this study aimed to evaluate this profile in ethanolic extracts of young, adult and senescent leaves, as well as their antioxidant, photoprotective, antimicrobial, and virucidal potentials. Phytochemical analysis was performed by TLC (thin-layer chromatography) and showed the presence of flavonoids, tannins, and terpenes. The evaluation by UPLC-MS/MS (Ultra performance liquid chromatography - tandem mass spectrometer) evidenced the presence of caffeic (3.89 mgL-1), p-cumaric (6.13 mgL-1), and ferulic (0.58 mgL-1) acids, whilst, in GC/MS (Gas chromatography–mass spectrometry) analysis there was a greater amount of palmitic (51.17%), stearic (20.34%), linoleic (9.62%), and miristic (8.16%) fatty acids. The DPPH (2,2-Diphenyl-1-picrylhydrazyl) and ABTS+ (2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) radicals were used to verify the potential antioxidant activity, observing a better activity for the leaf extract in the adult phenological stage: 54.63 ± 1.06 µgmL-1 (DPPH) and 44.21 ± 1.69 mM (ABTS). The potential photoprotective activity of the extracts was determined by spectrophotometry and the in vitro values of SPF (Sun Protection Factor) in young and adult leaves (5.47 and 5.41, respectively) showed values close to the minimum SPF of 6.0 required by ANVISA (Brazilian Health Regulatory Agency). It was not observed an antimicrobial activity for Staphylococcus aureus with a minimum inhibitory concentration of 2000 μgmL-1, however the anti-herpetic assay against the Herpes simplex virus type 2 (HSV-2) showed a potent virucidal activity at the tested concentrations with CV50 value <0.195 μgmL-1 and a Selectivity Index (SI = CC50 / CV50) greater than 448. The results obtained in this study suggest that extracts of leaves of C. glabrata in their adult phenological stage have potential antioxidant, photoprotective and virucidal activity, considering in vitro test results.

Spodoptera frugiperda worm represents a major problem in maize crop and the use of insecticide is the most used control measure. The main problems related to this practice are related to the development of resistant worm lineages. Studies of plants with insecticidal properties to control this pest have grown due to the lower impacts of their use. The objective of this study was to evaluate the insecticidal potential of the plants Chrysanthemum morifolium (Asterales: Asteraceae), Dieffenbachia picta (Alismatales: Araceae), Sansevieira trifasciata (Asparagales: Asparagaceae) and Tagetes erecta (Asterales: Asteraceae) on Spodoptera frugiperda worm mortality. The worms were raised in the laboratory, and kept under artificial diet. For the plant bioassays third instar larvae were used in two methods, control contat and ingestion. The evaluation period was five days. Individuals who when touched with the tip of a brush in the last abdominal segments did not respond with coordinated movements were considered dead. All four evaluated plants C. morifolium, D. picta, S. trifasciata and T. erecta caused the death of a low number of S. frugiperda worms. The C. morifolium and S. trifasciata plants, despite the low mortality rate, were those that stood out with 13.19% and 12.49% dead worms at the 70% concentration at the end of the evaluations. The method of action varied between the two plants and for C. morifolium the method of contact and ingestion were statistically the same from day three while for S. trifasciata the method of contact was better and resulted in the death of more caterpillars. It is concluded that in spite of the low mortality with the extracts, the plants C. morifolium and S. trifasciata presented higher mortality than the others. Note that the extract is obtained in a crude way, having its minimum efficiency evaluated.

Extracts of species from the Cordia genus have been reported with potential biological activities, such as antioxidant, antimicrobial, antiviral, and antiparasitic. The aim of this study was to develop microemulsions containing ethanolic extracts of C. glabrata leaves and to evaluate their stability and biological activities. The five developed microemulsions presented physicochemical stability and presented Newtonian behavior when submitted to rheological analysis. The diameter values of the globules ranged between 225.74 and 273.33 nm and the zeta potential of the formulations remained between -22.40 and -25.08. All phenolic acids of the extract, quantified by HPLC, showed consistency after being microemulsified. The EC₅₀ values for the antioxidant activity by the DPPH scavenging method ranged between 38.13 and 45.54 µgmL^-1, and between 34.46 and 39.60 mM for the ABTS⁺ scavenging method. The virucidal activity presented a CV₅₀ <0.195 µgmL^-1 and a selectivity index greater than 20. The photoprotection results ranged between 2.14 to 2.84. The study revealed stable microemulsions and potentiation of the antioxidant effect in the microemulsified extracts.

Copaifera sp. is a native tree in the Amazon region. Copaiba oleoresin has components such as sesquiterpenes, which have anti-inflammatory and antioxidant potential. Liver cirrhosis is the end stage of liver disease with limited therapeutic options. We aimed to evaluate the effect of copaiba oleoresin supplementation on the liver of animals with thioacetamide (TAA)-induced cirrhosis. For the induction of liver cirrhosis, 100 mg/kg of TAA was administered intraperitoneally twice a week for 8 weeks. A total of 200 mg/kg/day of copaiba oleoresin was administered via gavage for the same period. Copaiba oleoresin supplementation improved cirrhosis-associated cachexia by increasing weight gain and body fat. In addition, copaiba oleoresin attenuated systemic inflammation, as shown by the decrease in the circulating C-reactive protein. In the liver, the copaiba oleoresin decreased carbonyl proteins and increased IL-10 compared with TAA-treated rats. TAA groups demonstrated increased SOD, catalase, GST, and GSH activity in the liver. In conclusion, the supplementation of copaiba oleoresin demonstrated a beneficial systemic effect in alleviating cirrhotic cachexia and antioxidant and anti-inflammatory action in the liver. However, it failed to improve the serological and histological markers of liver damage, which could be associated with the advanced stage of the disease.