Abstract The plant species identification process is one of the most critical stages of quality control of plant raw material. Microscopy serves as the most accessible means for this purpose. Epidermal appendages, such as trichomes, are important botanical markers of plant drugs, taking into account their presence or absence and micromorphology. Trichomes are useful in detecting adulterants or substitutes and in authenticating plant raw materials. The genus Solidago includes two morphologically similar South American species, S. chilensis Meyen and S. microglossa DC. (syn. S. chilensis var. megapotamica). The two species belong to the “S. chilensis” complex and are commonly called arnica-do-mato or arnica. They are morphologically separated primarily on the basis of the average length of the non-glandular trichomes present in the stems. The objective of this study was to search for microscopic markers for the identification and differentiation of these two species to support species identification and quality control of the vegetable raw material. For this purpose, the usual techniques of light and scanning electron microscopy were used. Five types of trichomes were found in this study: I. Simple non-glandular trichome, II. Uniseriate non-glandular trichome, III. Biseriate non-glandular trichome, IV. Flagelliform glandular trichome, and V. Capitate glandular trichome. S. chilensis has simple non-glandular, flagelliform glandular, and rarely capitate glandular trichomes. Whereas, in addition to its glandular trichomes, S. microglossa has two types of non-glandular trichomes: biseriate and uniseriate. Thus, the two South American species of Solidago can be microscopically identified and differentiated based on the presence and absence of the characteristic trichomes. These differences can serve as pharmacognostic subsidies for quality control of the evaluated species.

Abstract Essential oils from four Ocotea species collected in southern Brazil were evaluated for chemical composition using gas chromatography coupled with mass spectrometry. The primary compound identified in O. acutifolia essential oil was an unsaturated tetracyclic diterpene, phyllocladene (67.7%), followed by a sesquiterpene hydrocarbon, β-selinene (18.0%). The sesquiterpene fraction was predominant in oils from two collections of O. puberula; β-caryophyllene (25.2%) and globulol (22.6%) were the major compounds identified in collections 1 and 2, respectively. O. silvestris essential oil contained predominantly germacrene D and bicyclogermacrene. These compounds were also predominant in essential oil from O. indecora leaves collected from shady habitats. By contrast, essential oil extracted from O. indecora grown under direct sunlight contained mainly oxygenated sesquiterpenes, such as guaiol (30.2%), α-eudesmol (27.6%), and β-eudesmol (12.7%). Chemotaxis assays showed that Ocotea essential oils had no significant inhibitory activity on leukocyte migration compared with a chemotactic stimulant (lipopolysaccharide from Escherichia coli). However, the oils exhibited antifungal activity against Candida parapsilosis, with a minimum inhibitory concentration of 500 µg/mL. To our knowledge, this is the first study to investigate the in vitro antifungal and antichemotactic activities of essential oils from Ocotea species native to southern Brazil.

A espécie Eugenia brasiliensis Lam. apresenta a coloração dos frutos variável, sendo reconhecidas três variedades. Entretanto, a definição de variedades não é fácil para espécies de Myrtaceae e também não é amplamente aceita. Duas variedades de Eugenia brasiliensis, baseado na cor dos frutos (roxos e amarelos), tiveram a composição de seus óleos essenciais analisadas com a finalidade de obter indícios de variedade botânica para esta espécie. Embora, os componentes principais nos óleos das folhas fossem os mesmos monoterpenos para ambas as variedades, alfa-pineno, beta-pineno e 1,8-cineol, a variedade com frutos roxos acumulou maior quantidade de sesquiterpenos oxigenados (33,9%) do que aquela com frutos amarelos (3,8%). As diferenças principais ocorreram nos frutos roxos que apresentaram como componente principal o óxido de cariofileno (22,2%) e o alfa-cadinol (10,4%), não detectados no óleo das folhas, e o óleo dos frutos amarelos apresentou uma composição similar àquela observada para as folhas. Estas variedades de coloração dos frutos de E. brasilensis podem ser considerados como dois quimiotipos distintos, uma vez que na variedade com frutos roxos a rota biossintética para sesquiterpenos encontra-se mais operante do que naquela com frutos amarelos, onde são acumulados principalmente os monoterpenos.

Eugenia brasiliensis Lam. is a variable species concerning fruit colour, with three recognized varieties. However, the definition of varieties is not easy for Myrtaceae species and not widely accepted. Two fruit colour varieties (purple and yellow) of E. brasiliensis had their essential oil composition analysed in order to give support to the existence of varieties for this species. Although, the major components in the leaf oil are the same monoterpenes for both varieties, alpha-pinene, beta-pinene and 1,8-cineol, the purple fruit variety accumulates more oxygenated sesquiterpenes (33.9%) than the one with yellow fruits (3.8%). The major differences occurred in purple fruits that present as major components caryophyllene oxide (22.2%) and alpha-cadinol (10.4%), not found in the leaf oil, and the yellow fruit oil presented a similar composition as observed for the leaves. These fruit colour varieties of E. brasilensis can be considered as two distinct chemotypes, since the sesquiterpene pathway is more operant in the purple variety than in the yellow one, in which monoterpenes are mainly accumulated.