Chemical composition of extracts and fractions from Miconia ibaguensis (MELASTOMATACEAE) leaves and evaluation of biological activities.

The study aimed to assess the chemical composition of Miconia ibaguensis leaves extracts and fractions obtained from the ethanolic extract (EE), along with evaluating their antifungal, antibacterial, antidiabetic, and antioxidant activities. The ethyl acetate fraction (EAF) exhibited potent antifungal activity against Candida spp (1.95 - 3.90 µg mL-1) and potent antioxidant activity in the DPPH (1.74 ± 0.07 µg mL-1), FRAP (654.01 ± 42.09 µmol ETrolox/gsample), and ORAC (3698.88 ± 37.28 µmol ETrolox/gsample) methods. The EE displayed inhibition against the α-amylase enzyme (8.42 ± 0.05 µg mL-1). Flavonoids, hydrolysable tannins, triterpenoids, and phenolic acids, identified in the EE and fractions via (-)-HPLC-ESI-MS/MS analysis, were found to contribute to the species' biological activity potentially. These findings suggest promising avenues for further research and potential applications in pharmacology and natural products, offering new possibilities in the fight against global health issues.

Reproductive biology and species geographical distribution in the Melastomataceae: a survey based on New World taxa.

BACKGROUND AND AIMS: Apomictic plants are less dependent on pollinator services and able to occupy more diverse habitats than sexual species. However, such assumptions are based on temperate species, and comparable evaluation for species-rich Neotropical taxa is lacking. In this context, the Melastomataceae is a predominantly Neotropical angiosperm family with many apomictic species, which is common in the Campos Rupestres, endemism-rich vegetation on rocky outcrops in central Brazil. In this study, the breeding system of some Campo Rupestre Melastomataceae was evaluated, and breeding system studies for New World species were surveyed to test the hypothesis that apomixis is associated with wide distributions, whilst sexual species have more restricted areas. METHODS: The breeding systems of 20 Campo Rupestre Melastomataceae were studied using hand pollinations and pollen-tube growth analysis. In addition, breeding system information was compiled for 124 New World species of Melastomataceae with either wide (>1000 km) or restricted distributions. KEY RESULTS: Most (80 %) of the Campo Rupestre species studied were self-compatible. Self-incompatibility in Microlicia viminalis was associated with pollen-tube arrest in the style, as described for other Melastomataceae, but most self-incompatible species analysed showed pollen-tube growth to the ovary irrespective of pollination treatment. Apomictic species showed lower pollen viability and were less frequent among the Campo Rupestre plants. Among the New World species compiled, 43 were apomictic and 77 sexual (24 self-incompatible and 53 self-compatible). Most apomictic (86 %) and self-incompatible species (71 %) presented wide distributions, whilst restricted distributions predominate only among the self-compatible ones (53 %). CONCLUSIONS: Self-compatibility and dependence on biotic pollination were characteristic of Campo Rupestre and narrowly distributed New World Melastomataceae species, whilst apomictics are widely distributed. This is, to a certain extent, similar to the geographical parthenogenesis pattern of temperate apomictics.

Microliciadeflexa and M.johnwurdackiana (Melastomataceae), two new species from the Brazilian Cerrado.

Microliciadeflexa sp. nov. and M.johnwurdackiana sp. nov. are described, illustrated and an updated identification key for the species of Microlicia from Clube Caça e Pesca Itororó de Uberlândia is provided. Microliciadeflexa occurs in Minas Gerais and Goiás States and is characterised by its linear-lanceolate and deflexed sepal on flower and immature fruit, long pedicel and indumentum of glandular trichomes, mixed with spherical, golden glands. Microliciajohnwurdackiana is endemic to Uberlândia and characterised by having indumentum of setose trichomes and spherical, golden glands, magenta petal with greenish abaxial surface at the apex and dimorphic stamens with bicolorous and tetrasporangiate anthers.

AbstractMicroliciadeflexa sp. nov. e M.johnwurdackiana sp. nov. são descritas, ilustradas e uma chave de identificação atualizada para as espécies de Microlicia do Clube Caça e Pesca Itororó de Uberlândia é fornecida. Microliciadeflexa ocorre nos estados de Minas Gerais e Goiás, e é caracterizada pela sépala linear-lanceolada e deflexa na flor e no fruto imaturo, pedicelo longo e indumento com tricomas glandulares misturados com glândulas esféricas, douradas. Microliciajohnwurdackiana é endêmica de Uberlândia, e caracterizada pelo indumento de tricomas setosos e glândulas esféricas, douradas, pétala magenta com a face abaxial esverdeada apenas no ápice e estames dimórficos com anteras bicolores e tetraesporangiadas.

Two new species of Microlicia D.Don (Melastomataceae, Microlicieae) from Chapada dos Veadeiros, Goiás State, Brazil.

Microlicia gracilis and Microlicia xylopodifera, endemic to Chapada dos Veadeiros, Goiás State, Brazil, are described, illustrated and the conservation status is also provided. Both species resemble Microlicia ordinata and Microlicia ramosa that are also endemic to Goiás, by having sessile leaf with serrate and ciliate margin, pedicellate flower, triangular and short sepal and dimorphic stamens with bicolorous and polysporangiate anthers. However, M. gracilis differs by the long internode (2-4 mm long), concolorous, semi-amplexicaul and lanceolate leaf, and petal acuminate at the apex. Microlicia xylopodifera differs in having a robust xylopodium, horizontal or slightly ascending leaf and a dense crown of glandular trichomes at the apex of flower bud.

ResumoMicrolicia gracilis e Microlicia xylopodifera, endêmicas da Chapada dos Veadeiros, são descritas, ilustradas e o estado de conservação fornecido. Ambas espécies se assemelham à Microlicia ordinata e Microlicia ramosa, também endêmicas de Goiás, por apresentarem folha séssil, com margem serreado-ciliada, flor pedicelada, sépala triangular, curta e estames dimórficos com anteras bicolores e poliesporangiadas. Contudo, M. gracilis diferencia-se pelo entrenó longo (2­4 m compr.), folha concolor, lanceolada e semiamplexicaule, e pétala acuminada no ápice. Microlicia xylopodifera difere por apresentar xilopódio robusto, folha horizontal ou levemente ascendente e uma coroa densa de tricomas glandulares no ápice do botão floral.

Sinopse de Miconia seção Miconia Dc. (Melastomataceae) no estado de Minas Gerais, Brasil / Synopsis of Miconia section Miconia Dc. (Melastomataceae) in the state of Minas Gerais, Brazil

Miconia, maior gênero de Melastomataceae, com cerca de 1050 espécies distribuídas na região neotropical, caracteriza-se pelas inflorescências terminais, pétalas de ápice arredondado ou emarginado e frutos carnosos. O gênero encontra-se subdividido em 12 seções, e as espécies da seção Miconia podem ser reconhecidas pelas anteras curtas e lineares, com ápice levemente atenuado e conectivo com apêndices ventrais. Este estudo foi baseado no exame morfológico de ca. 2300 exsicatas, depositadas em 15 herbários brasileiros, e revelou a ocorrência de 26 espécies da seção Miconia em Minas Gerais. São apresentadas ilustrações, chave de identificação, dados de floração e frutificação, comentários e Estado de conservação para todas as espécies de Miconia seção Miconia no Estado de Minas Gerais.

Miconia is the largest genus in Melastomataceae, with about 1050 species distributed through the neotropics, and can be recognized by the terminal inflorescences, rounded or emarginated petals and fleshy fruits. The genus is divided in 12 sections, and the species from section Miconia can be recognized by the short and linear anthers, with slightly attenuate apex and connective with ventral appendages. This study was based on morphological examination of about 2300 specimens from 15 Brazilian herbaria, which found 26 species of the section Miconia in Minas Gerais. We present illustrations, identification key, data on flowering and fruiting, comments, and conservation status for all species of Miconia section Miconia in Minas Gerais.