The secondary metabolites of the aerial parts of Phyllanthus acuminatus Vahl (Phyllanthaceae) and the biological activity of one of them were characterized in this study. This chemical investigation led to isolation of two lignans, luclaricin (1), a new arylnaphtalene-typelignan, and justicidin B (2). The structures of isolated compounds were determined based on 1D and 2D-NMR, HRESIMS and IR. The cytotoxic activity of justicidin B was assessed against tumor cell lines (MCF-7, U251, NCI-ADR/RES, NCI-H460, OVCAR-3, HT29 and K562) and a non-tumor cell line (HaCat) using sulforhodamine B assay. Justicidin B showed strong cytotoxic activity against the tumor cell lines HT29, K562 and U251 with GI50 values of 2.28, 3.29 and 5.76 mol L-1, respectively.

A series of β-carboline derivatives with amino or guanidinium were synthesized and evaluated in vitro against anti-Mycobacterium tuberculosis and for antiproliferative activities against nine human cancer cell lines. The compounds 1-(4-hydroxyphenyl)-3-carboxamide(ethylamine) β-carboline (24.9 µg mL-1) and 1-(4-methoxyphenyl)-3-carboxamide(ethylamine) β-carboline (26.9 µg mL-1) were the most active against M. Tuberculosis (MTB). Compounds 1-(4-hydroxyphenyl)-3-carboxamide(ethylamine) β-carboline and 1-(4-methoxyphenyl)-3-carboxamide(propylamine) β-carboline, which had the same substituted groups, inhibited the growth of all human tumor cell lines with growth inhibitory activity (GI50) values from 1.37 to 9.20 mmol L-1. Also in this series, compounds 1-(4-hydroxyphenyl)-3-carboxamide(propylamine) β-carboline and 1-(3-nitrophenyl)-3-carboxamide(propylamine) β-carboline demonstrated significant activity against NCI/ADR cells. Among compounds with a terminal guanidine group, compounds 1-(4-hydroxyphenyl)-3-carboxamide(ethyl)guanidine β-carboline (27.8 µg mL-1) and 1-(3-nitrophenyl)-3-carboxamide(ethyl)guanidine β-carboline (37.4 µg mL-1) demonstrated the greatest activity against MTB. Additionally, compounds 1-(4-methoxyphenyl)-3-carboxamide(ethyl)guanidine β-carboline (GI50 = 0.45 mmol L-1) effectively inhibited growth and was highly selective against NCI/ADR. The in silico study revealed that 1-(4-hydroxyphenyl)-3-carboxamide(ethylamine) β-carboline, 1-(4-methoxyphenyl)-3-carboxamide(ethylamine) β-carboline, 1-(4-hydroxyphenyl)-3-carboxamide(propylamine) β-carboline, 1-(4-methoxyphenyl)-3-carboxamide(propylamine) β-carboline and 1-(3-nitrophenyl)-3-carboxamide(propylamine) β-carboline compounds follow the rules established by Lipinski, suggesting that this compound has no problems with oral bioavailability.

The essential oil of roots of Jatropha ribifolia, obtained by hydrodistillation, was characterized in terms of its chemical composition by chromatographic method with flame ionization detection (GC-FID) and gas chromatography coupled to electron ionization mass spectrometry (GC-MS). The analyses and identification pointed by mass fragmentation pattern and retention index revealed the presence of 49 compounds, representing 91.4% of the total oil, with 39.5% of monoterpenes, 43.0% of sesquiterpenes and 8.5% of phenylpropanoids. The major compounds of the oil were β-pinene (9.2%), isoeugenol methyl ether (8.5%), vatirenene (8.4%), α-gurjunene (7.0%), endo-8-hydroxy-cycloisolongifolene (6.6%), α-pinene (6.4%) and p-menth-1-en-8-ol (5.2%). The fractionation by preparative thin layer chromatography (TLC) allowed obtaining five fractions (F1-F5) with different compound contents from the original oil. Some essential oil components showed a significant increase in their levels after fractionation, as borneol (17.9%, F1), 3-thujopsanone (19.1%, F4), isoeugenol methylether (21.2%, F2), 8-oxo-9H-cycloisolongifolene (21.4%, F4), 8-cis-5(1H)-azulenone,2,4,6,7,8,8a-hexahydro-3,8-dimethyl-4-(1-methylethylidene) (23.1%, F4) e endo-8-hydroxy-cycloisolongifolene (38.6%, F2). These fractions and oil were tested in vitro against nine human cancer cell lines by sulforhodamine B assay. The Jatropha oil was more effective in inhibiting the growth of cells NCI-H460 (drug resistant ovarian; GI50 6.2 µg mL–1) and OVCAR-3 (ovarian; GI508.0 µg mL–1). The cancer cells line PC-3 (prostate) was more sensitive to the effects of the fractions showing significant values of GI50 such as for fraction F1, F2 and F4 (< 0.25 µg mL–1). In general the antiproliferative activity of the fractions was more pronounced than that of crude oil.

The chemical study of the orchid Maxillaria picta resulted in the isolation of the bioactive stilbenes phoyunbene B and phoyunbene C, in addition to four phenolic acids, one xanthone, steroidal compounds and two triterpenes. Crude extract, fractions, subfractions and the isolated xanthone were evaluated for anticancer activity against human tumor cell lines and against evolutionary forms of T. cruzi and L. amazonensis. The structures of the compounds were determined by GC-MS, and ¹H NMR, 13C NMR spectral methods as well as bidimensional techniques.

The cytotoxicity of a hexanic fraction produced from the ethanolic crude extract, obtained from Jatropha ribifolia (Pohl) Baill, Euphorbiaceae, roots was evaluated against ten human cancer cell lines (MCF-7, NCI-ADR/RES, OVCAR-3, PC-3, HT-29, NCI-H460,786-O, UACC-62, K-562, U251) compared with doxorrubicine as positive control. Compounds jatrophone and cyperenoic acid were isolated from the hexanic extract and characterized by spectroscopic techniques (NMR of ¹H, 13C and IR). The in vitro antiproliferative activity of jatrophone showed selectivity in a concentration dependent way with Total Inhibition growth of: glioma 0.57 µg mL-1 (U251), breast cancer 9.2 µg mL-1 (MCF-7), adriamycin-resistant ovarian cancer 0.96 µg mL-1 (NCI-ADR/RES), kidney 4.2 µg mL-1 (786-0), prostate cancer 8.4 µg mL-1 (PC-3), colon cancer 16.1 µg mL-1 (HT29) and leukemia 0.21 µg mL-1 (K-562).

As sementes de Pterodon pubescens Benth. (Pp), disponíveis comercialmente no Brasil, são utilizadas na medicina popular em preparações anti-inflamatórias, analgésicas e anti-reumáticas. O presente estudo demonstrou as propriedades antinociceptivas da mistura de isômeros 6α-hidroxi-7β-acetoxi-vouacapano-17β-oato de metila e 6α-acetoxi-7β-hidroxi-vouacapano-17β-oato de metila (C1) isolada de Pp, empregando modelos experimentais diferentes. Um estudo de estabilidade foi realizado para investigar a relação da microencapsulação por "spray-drying" na manutenção do efeito antinociceptivo. Para isso, amostras de C1 e extrato de Pp foram monitorados no estudo de estabilidade acelerada, avaliando tanto amostras microencapsuladas como não microencapsuladas. Foi observado que a amostra C1 possui atividade antinociceptiva, revelada pelos ensaios das contorções abdominais e de formalina; foi observada também atividade significativa antialodínica, mas não efeito anti-hiperalgésico. A microencapsulação manteve a atividade e integridade de C1 e do extrato bruto de Pp, demonstrando que a microencapsulação por "spray drying" é uma alternativa útil para aumentar o tempo de prateleira.

Pterodon pubescens Benth. (Pp) seeds, commercially available in Brazil, are used in folk medicine in anti-inflammatory, analgesic, and anti-rheumatic preparations. The present study demonstrated the antinociceptive properties of isomers 6α-hydroxy-7β-acetoxy-vouacapan-17β-oate methyl ester and 6α-acetoxy-7β-hydroxy-vouacapan-17β-oate methyl ester (C1), isolated from (Pp), employing different experimental models. A stability study was performed to investigate the relationship of microencapsulation by spray-drying on the maintenance of antinociceptive action. Therefore, C1 and Pp extract samples were monitored in accelerated stability study, evaluating both microencapsulated and non-microencapsulated samples. It was observed that sample C1 possess antinociceptive activity revealed by writhing and formalin tests; C1 showed significantly anti-allodynic, but not antihyperalgesic effect; the microencapsulation maintained the activity and integrity of both, sample C1 and Pp crude extract; microencapsulation by spray drying is a useful alternative to increase shelf life.