In the present study, a quassinoid, neosergeolide, isolated from the roots and stems of Picrolemma sprucei (Simaroubaceae), the indole alkaloids ellipticine and aspidocarpine, isolated from the bark of Aspidosperma vargasii and A. desmanthum (Apocynaceae), respectively, and 4-nerolidylcatechol, isolated from the roots of Pothomorphe peltata (Piperaceae), all presented significant in vitro inhibition (more active than quinine and chloroquine) of the multi-drug resistant K1 strain of Plasmodium falciparum. Neosergeolide presented activity in the nanomolar range. This is the first report on the antimalarial activity of these known, natural compounds. This is also the first report on the isolation of aspidocarpine from A. desmanthum. These compounds are good candidates for pre-clinical tests as novel lead structures with the aim of finding new antimalarial prototypes and lend support to the traditional use of the plants from which these compounds are derived.Key words: neosergeolide -ellipticine -aspidocarpine -4-nerolidylcatechol -Pothomorphe peltata -Picrolemma spruceiAspidosperma spp.Malaria is the main cause of economic loss and high morbidity in the world today and continues to be endemic to tropical regions such as the Amazon. In the Brazilian Amazon, 1.6 million positive plates (thick smears) in a total of 8 million diagnostic tests for malaria were registered from January 2004 to February 2007 (Ministério da Saúde, Sivep-Malaria 2007). The lack of an effective vaccine and the increasing expansion of strains of Plasmodium falciparum presenting resistance towards commonly used, low-cost antimalarials make control of this disease difficult (Olliaro & Bloland 2001, Wellens & Plowe 2001, Vieira et al. 2001, Gonzales et al. 2003, Alecrim et al. 2006. As a result, the World Health Organization (WHO 1978(WHO , 1995 has been promoting research on natural product based drugs for treatment of disease and many plant species have been evaluated for antimalarial activity (Weniger et al. 2004). In these studies, emphasis has been on the discovery of lead compounds for drug development (Gundidza & Chinyanganya 1999). The rational search for active substances in medicinal plants is a very promising and cost-effective strategy for antimalarial drug discovery. This approach benefits from the accumulated knowledge of the curing capacity of plants possessed by inhabitants of malaria endemic regions and permits the extensive evaluation of natural products derived from these sources (Campbell et al. 1997, 1998, Brandão et al. 1992, 1997, Krettli et al. 2001, Andrade-Neto et al. 2004a.This triage of useful and effective plants is at the heart of traditional medicinal knowledge and is an extremely important source of therapeutic compounds in use today. Important semi-synthetic, low-cost, highly effective antimalarial drugs such as the quinolines (chloroquine, mefloquine, primaquine, etc.) and artemisinin derivatives (sodium artesunate, arteether, artemether, etc.) owe their initial discovery to the isolation and structural identi...

-4.0 μg/L) and 3 was only cytotoxic toward the leukaemia HL-60 strain (IC 50 = 11.8 µg/L). Quassinoids 1 and 2 (LC 50 = 3.2-4.4 mg/L) displayed greater lethality than derivative 4 (LC

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Biological evaluation and quantitative analysis of antioxidant compounds in pulps of the Amazonian fruits bacuri (Platonia insignis Mart.), ing a (Inga edulis Mart.), and uchi (Sacoglottis uchi Huber) by UHPLC-ESI-MS/MS lg/mL), whereas uchi and its main metabolite bergenin displayed moderate antimicrobial activities.The results shed light into the potentials of Amazonian fruit sources. Practical applicationsPlant phenolics are essential components of functional foods, due to their antioxidant and enzyme inhibition activities, which are directly linked to several diseases prevention. This is the first study about the quantification of antioxidant compounds in the Amazonian fruits: bacuri, ing a, and uchi.Although they are quite consumed in the North region of Brazil, there are no bio-products made from them. This study aimed to elucidate the knowledge about the chemical composition and potentialities within these fruits with the practical purpose of highlighting them to future commercial applications. In addition, once we indicate their capabilities, we contribute with local populations in respect to the production of such fruits, which still is a family activity. K E Y W O R D Santioxidant activity, bacuri, ing a, antioxidant compounds, uchi J Food Biochem. 2018;42:e12455.

Diseases transmitted by the mosquito Aedes aegypti, Culicidae, are a serious public health problem worldwide, especially because of the increasing resistance to synthetic insecticides. Volatile oils are botanicals with interesting multi-target properties, but with reduced applications due to its volatility and water solubility. For this reason, nanoemulsions containing volatile oils are an important alternative for the mosquito control. The volatile oil of leaves Piper alatipetiolatum Yunck., Piperaceae, was characterized mostly by sesquiterpenes, such as ishwarone (78.6%), ishwarol B (8.2%), β-elemene (6.9%), selin-11-en-4α-ol (2.9%), and ishwarane (2.4%). The volatile oil showed lower ovicidal activity (19 to 100%), larvicidal activity (LC 50 33.74 ppm), and pupicidal activity (LC 50 65.06 ppm) as compared with its nanoemulsion that presented higher ovicidal activity (47.7 to 100%), larvicidal activity (LC 50 6.37 ppm), and pupicidal activity (LC 50 9.33 ppm) against Ae. aegypti. The volatile oil nanoemulsion was characterized with approximately spherical morphology, with an average size of 316 ± 8 nm, PDI of 0.44 ± 0.01, zeta potential of − 8.5 ± 0.1 mV, and pH of 5.3 ± 0.1. These results indicated that the nanoemulsion containing the encapsulated volatile oil was effective to interrupt the development of immature forms of Ae. aegypti and represents an efficient alternative tool to control this vector, contributing to vector control of dengue and other related diseases.

The mosquitoes vectors of the genus Aedes and Anopheles present resistance to several commercial insecticides, which are also toxic to non-predators targets. On the other hand, essential oils are a promising source of insecticides. Thus, in this work, the essential oil from the leaves of Piper purusanum was characterized by gas chromatography based approaches and evaluated as biodefensive against malaria and dengue vectors. The main compounds of P. purusanum essential oil were β-caryophyllene (57.05%), α-humulene (14.50%) and germacrene D (8.20%). The essential oil inhibited egg hatching (7.6 ± 1.5 to 95.6 ± 4.5%) caused larval death (LC 50 from 49.84 to 51.60 ppm) and inhibited the action of acetylcholinesterase (IC 50 of 2.29 µg/mL), which can be related to the mechanisms of action. On the other hand, the biological activity of β-caryophyllene, α-humulene and germacrene D were higher than the essential oil. In addition, these sesquiterpenes and essential oil did not show a lethal effect on Toxorhynchites splendens, Anisops bouvieri, Gambusia a nis and Diplonychus indicus (LC 50 from 2098.80 to 7707.13 ppm), although D. indicus is more sensible (SI/PSF from 48.56 to 252.02 ppm) to essential oil, representing a natural alternative against these relevant vectors.* Con dence limit of 95%. Letters in the same column indicate statistical differences (ANOVA and Tukey p < 0.05). r 2 -Linear regression.

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