Maria L.F. Salatino

Traditional uses, chemistry and pharmacology of Croton species (Euphorbiaceae)

Croton is a genus of Euphorbiaceae comprising around 1,300 species, widespread in tropical regions of the Old and New Worlds. Several species have a long role in the traditional use of medicinal plants in Africa, Asia and South America. Popular uses include treatment of cancer, constipation, diabetes, digestive problems, dysentery, external wounds, fever, hypercholesterolemia, hypertension, inflammation, intestinal worms, malaria, pain, ulcers and weight-loss. Several species of Croton have a red sap, in some species containing proanthocyanidins and/or alkaloids. The latter may be taspine or some of several benzylisoquinoline-like compounds. Diterpenes are very common in Croton, corresponding to clerodanes, cembranoid, halimanes, kauranes, labdanes, phorbol esters, trachylobanes and sarcopetalanes. Some species are aromatic due to the possession of volatile oils. Representatives of new classes of compounds (phenylbutanoids, glutarimide alkaloids, sarcopetalane diterpenes) have been isolated from Croton species. While laticifers have been described in Croton species, so far there are no anatomical studies about secretory structures of volatile oil. Few studies about flavonoids have been carried out with Croton species. Chemical affinities are apparent in the genus, grouping species with (i) kauranes and/or labdanes, (ii) trachylobanes and (iii) alkaloids. Pharmacological assays have frequently corroborated the traditional uses of Croton species. A great part of pharmacological assays with Croton substances dealt with the clerodane trans-dehydrocrotonin, a wide diversity of effects having been noticed, including hypolipidemic, hypoglycaemic, anti-oestrogen and anti-cancer. Cytotoxic effects also have been observed in assays with alkaloids (taspine) and with secokaurene, labdane and cembranoid diterpenes. Several other effects of Croton substances have been registered, including anti-hypertensive, anti-inflammatory, antimalarial, antimicrobial, antispasmodic, antiulcer, antiviral and myorelaxant.

Phylogeny of Rutaceae based on twononcoding regions from cpDNA

Primarily known only by the edible fruits of Citrus, Rutaceae comprise a large (c. 160 genera and 1900 species), morphologically diverse, cosmopolitan family. Of its extraordinary array of secondary chemical compounds, many have medicinal, antimicrobial, insecticidal, or herbicidal properties. To assist with the much-needed suprageneric reclassification and with studies of evolution of chemical compounds and biogeographic history of the family, here we included sequence data (from two noncoding regions of the chloroplast genome-rps16 intron and trnL-trnF region) from 65 species in 59 genera (more than one third of those in the family) that represented all subfamilies and tribes and more genera of Toddalioideae and of neotropical groups than previous studies. Results confirmed that Cneorum, Ptaeroxylon, Spathelia, and Dictyoloma form a clade sister to the remaining Rutaceae, none of the subfamilies with more than one genus (except Aurantioideae) is monophyletic, and characters of the ovary and fruit are not reliable for circumscription of subfamilies. Furthermore, clades are better correlated with geographic distributions of the genera than with ovary and fruit characters. Circumscriptions of subfamilies and tribes (and some subtribes of Rutoideae) must be reevaluated. Results are discussed in light of geographic distributions, caryology, chemotaxonomy, and other molecular studies.

Foliar flavonoids of Annonaceae from Brazil: taxonomic significance

Foliar flavonoids of 31 species of the Annonaceae native to Brazil, amounting to 76 compounds, were isolated and identified. All phenols found were glycosides of either flavones (apigenin, scutellarein, hispidulin and luteolin) or flavonols (kaempferol, rhamnocitrin, 6-hydroxyrhamnocitrin, quercetin, isorhamnetin and rhamnetin), with the latter predominating. Some members of the tribe Bocageeae are distinctive for accumulating 6-oxygenated flavones and flavonols, in addition to 7-O-methylated flavonols, a feature possibly linked to the assumed advanced condition of the tribe within the family. Members of Duguetia stand out for the apparent absence of quercetin glycosides. Anaxagorea dolichocharpa seemingly lacks flavones and flavonols entirely. A UPGMA analysis based on the distribution of flavonoids does not group the analyzed species according to the available tribal division of the Annonaceae. However, several taxonomically meaningful groupings emerged through the multivariate analysis.

Alkanes of foliar epicuticular waxes of velloziaceae

Abstract One hundred and ten species of Velloziaceae were surveyed for the distribution of the alkanes in their foliar epicuticular waxes. Longer chains were found in waxes of representatives of subfamily Barbacenioideae, the main homologues being mostly n -C 33 or n -C 35 except most members of Pleurostima , which had n -C 31 or n -C 33 the main alkane. In Vellozioideae, the main alkane was chiefly n -C 29 . The results support proposals for the establishment of Burlemarxia and the re-establishment of Pleurostima , but does not lend support to the recognition of Brazilian Xerophyta as distinct from Vellozia and of Aylthonia as distinct from Barbacenia . In some cases very small or no differences were noted among the alkane profiles of different specimens of the same species, but in other cases substantial differences were detected.

Alkanes from foliar epicuticular waxes of Huberia species: Taxonomic implications

Abstract Alkanes of foliar epicuticular waxes of 18 samples corresponding to eight species of Huberia DC. (Melastomataceae) were analysed. Two patterns of distribution were found, one characterized by samples with C 31 or C 33 and the other with C 29 as the main homologue. These patterns are recognized in cluster analysis based on Euclidean distances and UPGMA. Huberia glazioviana and H. semiserrata showed intraspecific differences of alkane patterns, while H. ovalifolia and H. nettoana had conservative distributions, irrespective of variations in habitats where the species grow. We suggest that the alkanes can be a good taxonomic character at the species level for some taxa but not for others. The results of this and many other investigations with alkanes, showing substantial variation at the species level and below, cast doubts as to the usefulness of alkane distributions at higher hierarchic levels.

Five vicariant genera from Gondwana: the Velloziaceae as shown by molecules and morphology [corrected].

BACKGROUND AND AIMS The amount of data collected previously for Velloziaceae neither clarified relationships within the family nor helped determine an appropriate classification, which has led to huge discordance among treatment by different authors. To achieve an acceptable phylogenetic result and understand the evolution and roles of characters in supporting groups, a total evidence analysis was developed which included approx. 20 % of the species and all recognized genera and sections of Velloziaceae, plus outgroups representatives of related families within Pandanales. METHODS Analyses were undertaken with 48 species of Velloziaceae, representing all ten genera, with DNA sequences from the atpB-rbcL spacer, trnL-trnF spacer, trnL intron, trnH-psbA spacer, ITS ribosomal DNA spacers and morphology. KEY RESULTS Four groups consistently emerge from the analyses. Persistent leaves, two phloem strands, stem cortex divided in three regions and violet tepals support Acanthochlamys as sister to Velloziaceae s.s., which are supported mainly by leaves with marginal bundles, transfusion tracheids and inflorescence without axis. Within Velloziaceae s.s., an African Xerophyta + Talbotia clade is uniquely supported by basal loculicidal capsules; an American clade, Barbacenia s.l. + Barbaceniopsis + Nanuza + Vellozia, is supported by only homoplastic characters. Barbacenia s.l. (= Aylthonia + Barbacenia + Burlemarxia + Pleurostima) is supported by a double sheath in leaf vascular bundles and a corona; Barbaceniopsis + Nanuza + Vellozia is not supported by an unambiguous character, but Barbaceniopsis is supported by five characters, including diclinous flowers, Nanuza + Vellozia is supported mainly by horizontal stigma lobes and stem inner cortex cells with secondary walls, and Vellozia alone is supported mainly by pollen in tetrads. CONCLUSIONS The results imply recognition of five genera (Acanthochlamys (Xerophyta (Barbacenia (Barbaceniopsis, Vellozia)))), solving the long-standing controversies among recent classifications of the family. They also suggest a Gondwanan origin for Velloziaceae, with a vicariant pattern of distribution.

‘Green propolis’: unreported constituents and a novel compound from chloroform extracts

SUMMARY Analyses from chloroform extracts are reported for two samples of ‘green propolis’ from the south of Minas Gerais State (south-east Brazil), listing a variety of compounds, mostly benzoic or cinnamic acid derivatives. Most compounds were identified by GC/EIMS either as mixtures or in pure form, some of them being analysed as the corresponding methyl esters. Derivatives of benzoic acid, benzaldehyde, prenylated and non-prenylated cinnamic acid, chromane, chromene and some other compounds were found in the more polar fractions of chromatographic columns of both samples. Among the substances analysed, several had not been reported in propolis and one (3–prenylcinnamic acid allyl ester) is a new compound, which appeared in highest amounts in both samples. Its structure was determined by mass, IR and 1H NMR spectroscopy. The samples have similar composition, but phenols bearing a straight and long hydrocarbon chain were detected in only one sample. The comparative analysis of extracts from three solvents suggests that the current trend of analysing only alcoholic extracts in studies of propolis composition is bound to overlook or miss important propolis constituents.

Flavonoids of Lavoisiera, Microlicia and Trembleya (Melastomataceae) and their taxonomic meaning

Leaves of species of three closely related genera of Melastomataceae, Lavoisiera, Microlicia and Trembleya were analyzed for their flavonoid composition. A total of 116 compounds were obtained, comprising 69 flavonol and 47 flavone glycosides. The common occurrence of flavones, including 6-oxygenated derivatives, characterize Lavoisiera (which often yielded methoxylated flavonols and flavones). Flavonols predominate in species of Microlicia. The flavonoid patterns of Trembleya are rather confusing, some species being akin to Lavoisiera, others to Microlicia. UPGMA analysis using the flavonoid aglycones as characters and the samples analyzed as OTUs gives no complete resolution for the three genera, but provides clusters combining exclusively or preferentially species of either Lavoisiera and Microlicia. Species of Trembleya emerge from the phenogram interspersed among species of the other genera. The data suggest the recognition of Lavoisiera and Microlicia and the lumping of species of Trembleya with either of these genera. If greater flavone diversity is viewed as indicative of further evolutionary advancement, shrubby habits in Microliceae (Lavoisiera and Trembleya) should be regarded as derived from herbaceous ones (Microlicia).

Flavonoids of species of Cuphea (Lythraceae) from Brazil

Abstract From 16 species of Cuphea collected in “campos rupestres”, an altitudinal ecosystem found in Southeast and Central Brazil, 35 flavonoids have been identified. Most compounds are 3-O-glycosides of flavonols, but flavones were also found. Cuphea is akin to Diplusodon (another lythraceous genus) due to a frequent occurrence of derivatives of myricetin and the presence (though not frequent) of glycosides containing glucuronic acid. The mentioned genera may be distinguished from one another by the following characters, found in samples of Cuphea: presence of derivatives of rhamnetin and isorhamnetin; a rare occurrence of derivatives of kaempferol and flavones; a relatively frequent occurrence of glycosides of galactose; an apparent absence of glucuronic acid in glycosides of myricetin. Among the sections of Cuphea, Trispermum stands out, thanks to an absence of kaempferol and methylated flavonols (rhamnetin and isorhamnetin). The occurrence of flavone glycosides in members of subsection Hilariella (section Euandra) distinguishes them from species of Oidemation. The general flavonoid pattern of Cuphea seems to support proposals of seggregation of the genus as a well differentiated taxon among the Lythraceae.

Hydrocarbons of leaf epicuticular waxes of Pilocarpus (Rutaceae): Taxonomic meaning

Abstract The hydrocarbon patterns of the foliar epicuticular waxes of 11 species of Pilocarpus (Rutaceae) are presented. P. jaborandi has a unique pattern of wax hydrocarbons, due to the presence of relatively high amounts of 1-phenyl-5-vinyl, 5,9-dimethyl-decane. Most species presented either C 29 or C 31 as main n -alkanes and they may be distinguished by the two most abundant alkanes of each distribution. Two varieties and three subspecies of P. spicatus were studied, which can be characterized by their alkane patterns. A cluster analysis using UPGMA splits the samples analyzed into three groups: (a) two samples of P. jaborandi , both with the aromatic hydrocarbon as main constituent; (b) species with either a predominance of C 29 or a wide distribution of n -alkanes; (c) species with C 31 as main n -alkane. If the aromatic hydrocarbon is not considered, UPGMA splits the samples into two major clusters, with a branching pattern very similar to the previously described analysis, except for the inclusion of the three samples of P. jaborandi in close proximity into a cluster shared also by P. microphyllus and P. trachylophus .