Triterpenes and the Antimycobacterial Activity of Duroia macrophylla

Duroia macrophylla popularly known as “cabeça-de-urubú,” “apuruí,” or “puruí-grande-da-mata” occurs in the Amazon Forest. Its leaves and branches were collected twice and extracted with dichloromethane and methanol. All extracts were subjected to phytochemical investigation and terpenes and flavonoids were found in all dichloromethane and methanol extracts, respectively. Methanol extracts from both branches (1st collection) and leaves (2nd collection) presented hydrolyzed tannins, yet alkaloids were only detected in the dichloromethane and methanol extracts from branches at the 2nd collection. Phenol compounds were found in both dichloromethane extracts' collections. The action of every extract was assayed against Mycobacterium tuberculosis (RMPr, H37Rv, and INHr strains), showing that the dichloromethane extract from leaves (1st collection) has the major biological activity, with a MIC of 6.25 μg/mL for the INHr strain, 25.0 μg/mL for the RMPr strain, and ≤6.25 μg/mL for the H37Rv strain. The chromatographic fractioning of the dichloromethane extract from leaves (1st collection) yielded the isolation of two triterpenes: oleanolic and ursolic acids, which were identified by NMR analysis and reported for the first time in the Duroia genus

Structural, vibrational, and electronic properties of the glucoalkaloid strictosidine: A combined experimental and theoretical study

A detailed structural analysis and spectral behavior of the glucoalkaloid strictosidine, a precursor of all monoterpene indole alkaloids, are discussed. The experimental NMR, FTIR, and UV results were compared to the theoretical DFT spectra calculated by Becke using the three-parameter Lee-Yang-Parr (B3LYP) function with 6-31G(d) and 6-311++G(2d,p) basis sets. The theoretical geometry optimization data were compared with the X-ray data for precursors and similar structures in the associated literature. The similarity between the theoretical and experimental coupling constants values made it possible to affirm the values of dihedral angles and their configuration, reinforcing findings from previous stereochemical studies. Theoretical UV analysis agreed well with the measured experimental data, with bands assigned. Calculated HOMO/LUMO gaps show low excitation energy for strictosidine, justifying its stability and reaction kinetics. The molecular electrostatic potential map shows opposite potentials regions that form hydrogen bonds that stabilize the dimeric form, which were confirmed by excellent agreement of the dimeric form theoretical wavenumbers with the experimental IR spectrum. ESI-MS/MS data revealed patterns for the fragmentation of the protonated strictosidine molecule outlined by an NBO study. © 2016 Renyer Alves Costa et al

Estudo dos metabólitos secundários de Piper xylosteoides e Piper hemmendorffii (Piperaceae)

Orientadora: Profa. Dra. Beatriz Helena Lameiro de Noronha Sales MaiaDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Exatas, Programa de Pós-Graduação em Química. Defesa : Curitiba, 24/02/2015Inclui referências: p. 75-79Resumo: Neste trabalho foram estudados os compostos voláteis de folhas e caules de Piper hemmendorffii e folhas e galhos de Piper xylosteoides e ainda, os extratos em éter de petróleo das raízes e caules da espécie P. xylosteoides foram estudados fitoquimicamente. Os óleos essenciais foram extraídos por meio de hidrodestilação em aparelho de Clevenger e a identificação dos principais componentes foi feita por cromatografia de fase gasosa mono e bidimensional acoplada a espectrometria de massas resultando em 8 (CG 1D) e 40 (CG 2D) compostos identificados nas folhas e 4 (CG 1D) e 40 (CG 2D) nos caules de P. hemmendorffi; 9 (CG 1D) e 61 (CG 2D) constituintes nas folhas e 7 (CG 1D) e 36 (CG 2D) nos galhos de P. xylosteoides. Do total de 105 compostos diferentes identificados, dos quais 4 são monoterpenos, 3 álcoois alifáticos, 2 ésteres alifáticos, 8 monoterpenos oxigenados, 9 hidrocarbonetos alifáticos, 34 sesquiterpenos, 34 sesquiterpenos oxigenados, 2 aldeídos alifáticos e 9 arilpropanoides. O estudo fitoquímico dos caules e raízes de Piper xylosteoides resultou na identificação de 15 compostos sendo quatro arilpropanoides, um aldeído aromático, dois flavonoides, um ácido carboxílico aromático, um sesquiterpeno, cinco neolignanas e uma lignana. As estruturas dos compostos foram determinadas utilizando técnicas espectroscópicas de RMN 1D e 2D e todos os compostos identificados são descritos pela primeira vez para esta espécie vegetal, sendo que das seis neolignanas identificadas, quatro são inéditas e uma possui apenas um relato na literatura. Os extratos em éter de petróleo de caules, raízes, galhos e folhas de P. xylosteoides foram comparados quanto à composição química utilizando cromatografia de fase líquida de alta eficiência acoplado a um detector de arranjo de fotodiodos e concluiu-se que os extratos de caules e galhos possuem cromatogramas sobreponíveis, indicando que a composição química dos extratos é semelhante. Por outro lado, o extrato das folhas apresenta um perfil diferente dos outros e o extrato das raízes é o que apresenta o maior número de compostos. Palavras-chave: Fitoquímica. Piperaceae. Cromatografia Gasosa Bidimensional Abrangente.Abstract: This work contemplates the results from study of the essential oil from leaves and stem of Piper hemmendorffii and leaves and branches of Piper xylosteoides, and also results from the phytochemical investigation of the petroleum ether extract of roots and stem of P. xylosteoides. The essential oils were extracted by hidrodestillation using a Clevenger and the identification of the main components was perfomed using mono and two-dimensional gas chromatography coupled with mass spectrometry resulting in 8 (1D GC) and 40 (2D GC) substances in the leaves and 4 (1D GC) and 40 (2D GC) in the stem of P. hemmendorffii; 9 (1D GC) and 61 (2D GC) substances in the leaves and 7 (1D GC) and 36 (2D GC) in the branches of P. xylosteoides. Of 105 different components, 4 of them are monoterpenes, 3 are aliphatic alcohois, 2 aliphatic esters, 8 oxigenated monoterpenes, 9 aliphatic hydrocarbons, 34 sesquiterpenes, 34 oxigenated sesquiterpenes, 2 aliphatic aldehydes and 9 arylpropanoids. The phytochemical study of roots and stem of P. xylosteoides lead to the identification of 15 substances: four arylpropanoids, one aromatic aldehyde, two flavonoids, one aromatic carboxylic acid, one sesquiterpene, five neolignans and one lignan. The structures were determined using 1D and 2D NMR techniques and all the identified substances are being described for the first time in this species, four neolignans are reported for the first time and one was reported only one time in the literature. The petroleum ether extracts of stem, roots, branches and leaves of P. xylosteoides were compared with each other regarding the chemical composition using high performance liquid chromatography coupled with a photodiode array detector and was observed that the stem and branches extracts have very similar chromatogram, which indicates that the chemical composition of both extracts is very alike. On the other hand, the leaves extract exhibited a different profile from the others and the roots extract is the one with most components. Key-words: Phytochemistry. Piperaceae. Comprehensive Two-dimensional Gas Chromatography

Triterpenes and the antimycobacterial activity of duroia macrophylla huber (Rubiaceae)

Duroia macrophylla popularly known as "cabeça-de-urubú, " "apuruí," or "puruí-grande-da-mata" occurs in the Amazon Forest. Its leaves and branches were collected twice and extracted with dichloromethane and methanol. All extracts were subjected to phytochemical investigation and terpenes and flavonoids were found in all dichloromethane and methanol extracts, respectively. Methanol extracts from both branches (1st collection) and leaves (2nd collection) presented hydrolyzed tannins, yet alkaloids were only detected in the dichloromethane and methanol extracts from branches at the 2nd collection. Phenol compounds were found in both dichloromethane extracts' collections. The action of every extract was assayed against Mycobacterium tuberculosis (RMPr, H37Rv, and INHr strains), showing that the dichloromethane extract from leaves (1st collection) has the major biological activity, with a MIC of 6.25 μg/mL for the INHr strain, 25.0 μg/mL for the RMPr strain, and ≤6.25 μg/mL for the H37Rv strain. The chromatographic fractioning of the dichloromethane extract from leaves (1st collection) yielded the isolation of two triterpenes: oleanolic and ursolic acids, which were identified by NMR analysis and reported for the first time in the Duroia genus. © 2013 Daiane Martins et al

Chemical profile and biological activities of Deguelia duckeana A.M.G. Azevedo (Fabaceae)

Deguelia duckeana is popularly known as timbo and used by indigenous people as ictiotoxic. On account of there being no literature pertaining to the chemical profile or biological activity of this plant, the hexane, methanol and aqueous crude extracts from leaves, stems and roots were assayed that presented very high cytotoxic potential against Artemia salina, achieving 100% mortality in up to 5.0 mgmL-1 concentration, but lower antioxidant potential on 2,2-diphenyl-1-picryl-hydrazyl and Fe3+/Phenanthroline assays. The phytochemical analysis of crude extracts showed the presence of flavonoids and related compounds as major constituents as well as steroids in all of them, and tannins in polar extracts. All the extracts were assayed for antibacterial activity but only the hexane extract of stems showed moderate activity on Staphylococcus aureus, which was fractionated and yielded a mixture of 3,5,40-trimethoxy-4-prenylstilbene, lonchocarpine, 4-hydroxylonchocarpine and derricidine, reported for the first time in D. duckeana and other fraction with β-sitosterol and stigmasterol mixture . © 2013 Taylor and Franics