No abstract

No abstract

Natural products obtained from species of the genus Abuta (Menispermaceae) are known as ethnobotanicals that are attracting increasing attention due to a wide range of their pharmacological properties. In this study, the alkaloids stepharine and 5-N-methylmaytenine were first isolated from branches of Abuta panurensis Eichler, an endemic species from the Amazonian rainforest. Structure of the compounds was elucidated by a combination of 1D and 2D NMR spectroscopic and MS and HRMS spectrometric techniques. Interaction of the above-mentioned alkaloids with acetylcholinesterase enzyme and interleukins IL-6 and IL-8 was investigated in silico by molecular docking. The molecules under investigation were able to bind effectively with the active sites of the AChE enzyme, IL-6, and IL-8 showing affinity towards the proteins. Along with the theoretical study, acetylcholinesterase enzyme inhibition, cytotoxic, and immunomodulatory activity of the compounds were assessed by in vitro assays. The data obtained in silico corroborate the results of AChE enzyme inhibition, the IC 50 values of 61.24μM for stepharine and 19.55μM for 5-N-methylmaytenine were found. The compounds showed cytotoxic activity against two tumor cell lines (K562 and U937) with IC 50 values ranging from 11.77 μM to 28.48 μM. The in vitro assays revealed that both alkaloids were non-toxic to Vero and human PBMC cells. As for the immunomodulatory activity, both compounds inhibited the production of IL-6 at similar levels. Stepharine inhibited considerably the production of IL-8 in comparison to 5-N-methylmaytenine, which showed a dose dependent action (inhibitory at the IC 50 dose, and stimulatory at the twofold IC 50 one). Such a behavior may possibly be explained by different binding modes of the alkaloids to the interleukin structural fragments. Occurrence of the polyamine alkaloid

No abstract

No abstract

No abstract

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.

No abstract