ABSTRACT Many features of flowers comprise the key elements of the pollinating strategies of flowering plants. Our aims were to describe features that attract pollinators and to identify the pollination system of Petunia interior, a species for which bees have been suggested as the probable pollinators. Therefore, we described the morphology and floral biology, assessed nectar production, concentration, and composition, examined reproductive mode and identified pollinators. P. interior has a purple, infundibuliform, zygomorphic corolla with a short and wide tube and blue pollen. Flower opening and pollen release were asynchronous throughout the day. The pollen grains have pollenkitt on the surface. The nectar sugar composition has a proportion of sucrose lower than the proportion of glucose + fructose, and the nectar supply was constant, in small amounts, at a concentration between 16.6-23.1 %. The reproductive system is xenogamous and bees were the exclusive pollinators. P. interior exhibits a set of floral traits that prevent self-pollination and maintains attractiveness to the bees. The greater reproductive success under natural conditions highlights the importance of bees for the reproductive success of P. interior. As far as floral traits are concerned, only the sugar concentration in the nectar does not correspond to melittophily.

RESUMO A erva-mate (Ilex paraguariensis St. Hil) é uma espécie nativa da América do Sul. Progênies vegetais são grupos de plantas que apresentam diferenças em relação a sua produtividade, morfologia e possivelmente perfil fitoquímico. Neste trabalho, objetivou-se determinar os teores de metabólitos primários e secundários, assim como atividade antioxidante em folhas de progênies de erva-mate, morfologicamente caracterizadas. Foi avaliada a composição centesimal e níveis de metabólitos secundários em cinco plantas. Metilxantinas e compostos fenólicos foram determinados por UPLC-PDA, e a atividade antioxidante, por meio da medição da capacidade de sequestro do radical DPPH. Foram encontradas diferenças significativas na composição centesimal, e no conteúdo de cafeína, teobromina, rutina e ácido clorogênico, assim como atividade antioxidante nas progênies selecionas. Os valores de IC50 estiveram correlacionados com os níveis de ácido clorogênico ( r2 = 0,5242) e conteúdo de solúveis ( r2 = 0,7686). Os caracteres morfológicos observados nas folhas de erva-mate podem ser utilizados como uma ferramenta visando a obter matrizes com perfil fitoquímico diferenciado como fonte de material genético.

ABSTRACT Yerba-mate (Ilex paraguariensis St. Hil) is a native South American species. Plant progenies are populations that differ in terms of their productivity, morphology and phytochemical profile. This study aimed to determine the concentration of primary and secondary metabolites, such as antioxidants, in leaves, of yerba-mate progenies selected based on morphological characteristics. We evaluated the centesimal composition of secondary metabolites in the leaves of five yerba-mate plants. Methylxanthines and phenolic compounds were determined by UPLC-PDA, and antioxidant activity by measuring DPPH scavenging. Significant differences were found in centesimal composition and the contents of caffeine, theobromine, rutin and chlorogenic acid, as well as antioxidant activities, in selected progenies. The IC50 values were correlated with the chlorogenic acid levels ( r2 = 0.5242) and soluble content ( r2 = 0.7686). The morphological characteristics observed in yerba-mate leaves can be used as a tool for plant selection, to obtain matrices with different phytochemical profiles as a genetic material source.

Ilex paraguariensis is a native species to South America. Its economic importance is in the use of its leaves and twigs in the processing of a product popularly known as "chimarrão". The aim of this study was to evaluate the correlations between some physico-chemical process parameters in the oxidation of I. paraguariensis leaves oxidation. The leaves of Maté with age 1.0, 6.5 and 12.0 months were subjected to an oxidation process for 3 h under different relative humidity conditions (80, 90 and 99%) at 26°C. The extracts were evaluated using the experimental design techniques to maximize the oxidation conditions for the total polyphenols, antioxidant capacity, water activity and color. The condition of 90% humidity and leaf age 6.5 months resulted in lower lightness and yellow color of the product. Green color was not significantly influenced by the studied parameters. The highest levels of total phenols and antioxidant potential were found when the leaf age was one month and humidity was 90%. Thus, it could be concluded that the air humidity of the chamber and leaf age influenced the oxidation process of the leaves of Maté as well as the antioxidant capacity of the extract obtained.

A cafeína é uma substância derivada de bases purínicas que confere muitos benefícios à saúde e tem sido amplamente estudada em áreas relacionadas à saúde e ao desempenho humano. Neste sentido, esse estudo visou estimular a oxidação das folhas de Ilex paraguariensis, para obtenção de um produto semelhante ao chá-preto, produzido a partir de Camellia sinensis e, monitorar o teor de cafeína por HPLC. No delineamento experimental cruzaram-se três variáveis relacionadas à câmara: temperatura, umidade e luz, e duas associadas às folhas: umidade e idade. Os resultados indicam que o teor de cafeína decresce com o aumento da idade da folha, tornando nítido que folhas de 6,5 meses apresentam valores intermediários de cafeína, em relação às de 12 meses.

Caffeine is a substance derivate of purine basis that has many benefits, has been widely studied in areas related to health and human performance. In this sense, this work aims to simulate the oxidation of leaves of yerba mate, a process used to obtain the black tea from the Camellia sinensis leaves and monitor these to their caffeine content for HPLC. A factorial design of experiments was performed for five variables: temperature, humidity and light camera, moisture and age leaf. The results indicate that caffeine tend to decrease their content (%) with increasing leaf age. Making clear that 6,5 months is the intermediate age of the leaf whose values of caffeine are also intermediate.

La cafeína es una sustancia derivada de bases púricas que confiere muchos beneficios a la salud y ha sido ampliamente estudiada en las áreas relacionadas a la salud y al rendimiento humano. En este sentido, este estudio estuvo dirigido a estimular la oxidación de las hojas de Ilex paraguariensis, para obtener un producto similar al té negro, producido a partir de Camellia sinensis y controlar el contenido de cafeína por HPLC. En el experimento se cruzaron tres variables relacionadas a la cámara: temperatura, humedad y luz, y dos asociadas con las hojas: edad y humedad. Los resultados indican que el contenido de cafeína se reduce con el aumento de la edad de la hoja, dejando claro que hojas de 6,5 meses exhiben valores intermedios de cafeína, en relación a las de 12 meses.

This work aimed to study the oxidation of leaves of Ilex paraguariensis St. Hil, in a process similar to the oxidation of Camellia sinensis, with the purpose of developing new products based on yerba maté. So far, no previous systematic study about the oxidation of yerba maté has been found elsewhere. A Plackett-Burman experimental design was used for the screening of the significant parameters that affected the oxidation. The oxidation was indirectly quantified by following the changes in the product color, water activity, and pH with the time of processing. The factors that most influenced the process were the age of the leaves and the relative humidity of the oxidation chamber. The differences between the treatments were more evident after 3, 6 12 and 24 h of oxidation. The results could contribute to the developing of new products based on I. paraguariensis St. Hil, increasing the profitability of cultivation of this native species.