Phytochemistry and pharmacology of the genus Entandrophragma over the 50 years from 1967 to 2018: a 'golden' overview.

OBJECTIVES: For centuries, the genus Entandrophragma (Meliaceae), endemic to Africa, has been used in traditional medicine for the treatment of several illnesses. This review deals with large range of phytochemicals from the genus Entandrophragma and their pharmacological potentials covering the period from 1967 to 2018. KEY FINDINGS: Phytochemical investigations of the genus Entandrophragma led to the report of about 166 secondary metabolites which have been thoroughly summarized herein including some of their semisynthetic derivatives obtained from chemical transformations as well as their biological activities in the medicinal and agricultural domains. The limonoids or meliacins and their precursor called protolimonoids (protomeliacins) reported so far represent almost 69.28% of the total secondary metabolites obtained from the genus, and they display the most potent biological activities. Collectively, both classes of metabolites constitute the markers of Entandrophragma. However, squalene-type triterpenoids and sesquiterpenoids were reported only from the species E. cylindricum and therefore could be its chemotaxonomic markers. SUMMARY: The pharmacological investigations of the extracts of some species exhibited interesting results which support the traditional uses of these Entandrophragma plants in folk medicine. Some compounds revealed promising antiplasmodial and anti-inflammatory activities and deserve therefore further attention for new drug discovery.

Quantificação de fenóis totais presentes nas cascas de Trichillia catigua A. Juss (Meliaceae) / Quantification of total phenols present in the bark of Trichilia catigua A. Juss (Meliaceae)

Trichillia catigua A. Juss. é uma planta medicinal utilizada principalmente como estimulante, possivelmente devido à presença de fenóis. Entre os métodos utilizados para a determinação de polifenóis em matérias-primas vegetais destaca-se a análise por meio de ensaios espectrofotométricos por apresentarem boa sensibilidade, simplicidade, e ter custos mais acessíveis. O presente trabalho teve o objetivo de validar a metodologia analítica para determinação de polifenóis na casca de catuaba em pó. Utilizou-se o método de Hagerman & Butler para a quantificação dos polifenóis totais encontrando-se 7,96%. O método validado mostrou-se simples, rápido, seletivo, linear, exato, preciso, e robusto para ser executado na rotina de laboratório de controle de qualidade, constituindo uma possibilidade de análise desta planta medicinal.

Trichilia catigua A. Juss. is a medicinal plant used especially as a stimulant, possibly due to the presence of phenols. Among the methods used for the determination of polyphenols in raw plant materials is analysis through spectrophotometric assays since they have good sensitivity, are simple and more affordable. This study aimed to validate the analytical methodology for the determination of polyphenols in the bark of powder "catuaba". The method of Hagerman & Butler was employed in the quantification of total polyphenols, yielding 7.96%. The validated method has proven to be simple, rapid, selective, linear, accurate, precise and robust to be performed in the routine of a laboratory of quality control, constituting a possibility for the analysis of this medicinal plant.

An overview of the genus Xylocarpus.

The article deals with the chemical constituents isolated from all the Indian species of Xylocarpus viz. X. granatum, X. moluccensis, and X. mekongensis. A total of about 70 pure compounds of different classes have been covered. The article describes the biosynthetic pathway of limonoids and sources, bioactivities and chemical and physical constants of the different classes of compounds.

Classification of commercial Catuaba samples by NMR, HPLC and chemometrics.

For over a century, Catuaba has been used in Brazilian folk medicine as an aphrodisiac even though the identity of the plant material employed is often uncertain. The species recommended by the Brazilian Pharmacopeia is Anemopaegma arvense (Bignoniaceae), but many other plants, regionally known as Catuaba, are commercialised. Frequently, the quality control of such a complex system is based on chemical markers that do not supply a general idea of the system. With the advent of the metabolomics approach, a global analysis of samples becomes possible. It appears that (1)H-NMR is the most useful method for such application, since it can be used as a wide-spectrum chemical analysis technique. Unfortunately, the generated spectra is complex so a possible approach is to look at the metabolite profile as a whole using multivariate methods, for example, by application of principal component analysis (PCA). In the present paper, we describe for the first time a proton high-resolution magic angle spinning nuclear magnetic resonance ((1)H-HR-MAS NMR) method coupled with PCA for the metabolomic analysis of some commercial Catuaba samples, which provided a reduction in the time required for such analysis. A comparative study of HPLC, HR-MAS and liquid-NMR techniques is also reported.

Trypanocidal activity of Meliaceae and Rutaceae plant extracts.

The in vitro trypanocidal activity of 22 extracts and 43 fractions of plants belonging to the families Meliaceae and Rutaceae was evaluated. The extracts from leaves of Conchocarphus heterophyllus and branches of Trichilia ramalhoi were the most active. The trypanocidal activity seems to be increased by fractionation of the extracts. Fractions from C. heterophyllus and Galipea carinata were the most active and a 100% lysis of the parasites was observed for five fractions. From one of them were isolated two flavonoids: flavone and 7-methoxyflavone, which showed weak trypanocidal activity. The results obtained from the extracts and fractions revealed that the order Rutales is a promising source for the search of new drugs for Chagas disease. Phytochemical studies with the other active fractions are underway in order to isolate compounds, which could be associated with observed activities.