Resumen La tribu Miconiae estaba compuesta por los géneros Miconia, Clidemia, Leandra y Ossaea, pero trabajos recientes han reconocido a Miconia como el único género de la tribu. La diversidad morfológica de los tricomas en Melastomataceae se ha empleado con fines sistemáticos, especialmente el indumento foliar. En el presente trabajo se investigaron los tricomas del hipantio de 24 especies de Miconieae, 8 especies de Miconia sensu stricto y 16 especies de Leandra como aporte a la taxonomía de la tribu. Las muestras se obtuvieron de especímenes de herbario y plantas recolectados en un parque estatal en Paraná, Brasil. El indumento del hipantio de las muestras se analizó utilizando un microscopio electrónico de barrido. Nuestros resultados revelaron que los tricomas estrellados de pedúnculo largo aparecen solo en Miconia s.s., mientras que los tricomas dendríticos eglandulares y los tricomas glandulares aparecen solo en Leandra. Los tricomas mixtos con glándula lateral son menos frecuentes y se encontraron en ambos géneros. No sorprende, por lo tanto, que los hipantios de las especies investigadas presenten un indumento de potencial importancia taxonómica. Los caracteres del indumento de Miconia s.s. y Leandra pueden ser útiles en la taxonomía infragenérica de la nueva propuesta para la tribu Miconieae.

Abstract The tribe Miconieae was composed of a few genera, such as Miconia, Clidemia, Leandra, and Ossaea, but recent works have recognized Miconia as the only genus of the tribe. The morphological diversity of trichomes in Melastomataceae have been employed for systematic purposes, especially the foliar indumentum. In the present paper, hypanthium trichomes of 24 species of Miconieae were investigated, 8 species of Miconia sensu stricto and 16 species of Leandra, as a contribution to the taxonomy of the tribe. Samples were obtained from herbarium and plant specimens collected in a state park in Paraná, Brazil. The hypanthium indumentum of the samples was analyzed using a scanning electron microscope. Our results revealed that long-peduncle stellate trichomes appear only within Miconia s.s., while dendritic eglandular trichomes and glandular trichomes appear only in Leandra. Mixed trichomes with a lateral gland are less frequent and were found in both genera. It is not surprising, therefore, that the hypanthia of the investigated species possess indumentum of potential taxonomic significance. The characters of the indumentum of Miconia s.s., and Leandra may be useful in the infrageneric taxonomy of the new proposal for the tribe Miconieae.

Hybrid magnetite materials are interesting for both biomedical and catalytic applications due to their well-known biocompatibility, as well as their magnetic and electric properties. In this work we prepared Fe3O4 nanoparticles (NPs) coated with tannic acid (TA), a natural polyphenol, through two different synthetic routes, aiming to understand the influence of TA in the synthesis step and contribute to the development of water-dispersible magnetic materials. The coating process was verified by information obtained from transmission electron microscopy (TEM), zeta-potential and Fourier transform infrared (FTIR) spectroscopy. The incorporation of TA after Fe3O4 NPs production generated spherical NPs smaller than 10 nm, suggesting that TA plays a fundamental role in the nucleation and organization of Fe3O4 NPs. Data from both density functional theory (DFT) and FTIR allowed us to infer that Fe3O4 interacts mainly with the carbonyl groups of TA. Hybrid materials having improved water-dispersibility are very attractive for biomedical applications.

Duas amostras de bactérias psicrófilas foram isoladas do solo da Ilha do Rei Jorge, na Antártica. A análise filogenética baseada no gene do RNAr 16S (rrs) levou à correlação destes isolados com Sporosarcina aquimarina(99%) e Algoriphagus antarcticus(99%), com porcentagem de alinhamento de 99% e 98%, respectivamente. O sobrenadante do meio de cultura de ambos os isolados apresentou atividades proteolíticas detectadas por eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio e gelatina como substrato proteico. Sob estas condições, S. aquimarina apresentou uma protease de 55 kDa com melhor atividade em pH 7,0 e a 27°C. Também foi detectada uma única protease extracelular em A. antarcticus,no entanto com massa molecular em torno de 90 kDa e com melhor atividade em pH 9,0 e a 37°C. As proteases de ambos os isolados foram inibidas por 1,10-fenantrolina e EDTA, dois inibidores de metaloproteases. Este é o primeiro registro de detecção de proteases em ambas as espécies, e nossos resultados podem contribuir para ampliar o conhecimento básico de proteases provenientes do ambiente antártico e podem ajudar na prospecção de futuras aplicações biotecnológicas dessas enzimas.

Two psychrophilic bacterial samples were isolated from King George Island soil, in Antarctica. The phylogenetic analysis based on the 16S rRNA (rrs) gene led to the correlation with the closest related isolates as Sporosarcina aquimarina (99%) and Algoriphagus antarcticus(99%), with query coverage of 99% and 98%, respectively.The spent culture media from both isolates displayed proteolytic activities detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis containing gelatin as protein substrate. Under the employed conditions, S. aquimarina showed a 55 kDa protease with the best activity detected at pH 7.0 and at 27°C. A. antarcticusalso showed a single extracellular protease, however its molecular mass was around 90kDa and its best activity was detected at pH 9.0 and at 37°C. The proteases from both isolates were inhibited by 1,10-phenanthroline and EDTA, two metalloprotease inhibitors. This is the first record of protease detection in both species, and our results may contribute to broaden the basic knowledge of proteases from the Antarctica environment and may help prospecting future biotechnological applications of these enzymes.

Halophilic microorganisms are source of potential hydrolytic enzymes to be used in industrial and/or biotechnological processes. In the present study, we have investigated the ability of the moderately halophilic bacterium Halobacillus blutaparonensis (strain M9), a novel species described by our group, to release proteolytic enzymes. This bacterial strain abundantly proliferated in Luria-Bertani broth supplemented with 2.5% NaCl as well as secreted proteases to the extracellular environment. The production of proteases occurred in bacterial cells grown under different concentration of salt, ranging from 0.5% to 10% NaCl, in a similar way. The proteases secreted by H. blutaparonensis presented the following properties: (i) molecular masses ranging from 30 to 80 kDa, (ii) better hydrolytic activities under neutral-alkaline pH range, (iii) expression modulated according to the culture age, (iv) susceptibility to phenylmethylsulphonyl fluoride, classifying them as serine-type proteases, (v) specific cleavage over the chymotrypsin substrate, and (vi) enzymatic stability in the presence of salt (up to 20% NaCl) and organic solvents (e.g., ether, isooctane and cyclohexane). The proteases described herein are promising for industrial practices due to its haloalkaline properties.