Antineoplastic potential of the aqueous crude extract of Eugenia uniflora L. in human cervical cancer

Abstract Considering the high prevalence of human cervical cancer and the adverse effects of the available treatments, it is important to develop studies involving plants. Eugenia uniflora L. is a Brazilian native plant widely used in folk medicine and some biological effects have already been described. In this study, we investigated the biologicals effects of the aqueous crude extract of E. uniflora leaves in relation to the viability of human cervical cancer cells (SiHa), non-tumorigenic cells HaCaT and human lymphocytes. Our results demonstrated that different concentrations of E. uniflora's extract significantly inhibited the viability of the Siha cell line at 24, 48 and 72 hours of treatment, but did not induce significant changes in the HaCat cell line and human lymphocytes. Tumor cells had adhesion capacity, migration processes, ability of colony forming and the potential to recover its viability after treatment. withdrawal, significantly reduced. The nuclear morphology revealed chromatin condensation, and the flow cytometry showed predominantly cell death by apoptosis in the treated tumor cells. Therefore, the E. uniflora's extract may contribute for future studies aiming at new therapeutic perspectives for human cervical cancer.

Influence of foliar nutrients on phenol levels in leaves of Eugenia uniflora

Eugenia uniflora L., Myrtaceae, leaves contain high amounts of phenolic compounds which are responsible for several pharmacological activities. In order to evaluate the phenolics seasonal variation leaves were analysed on a monthly basis during the period of two years for the contents of hydrolysable tannins, total phenols, flavonoids, and nutrients (N, P, K, S, Ca, Mg, Mn, Zn, Cu, and Fe). Results were correlated with climate conditions (rainfall, humidity, and mean temperature) by Principal Component and ClusterAnalysis which allowed four groups to be distinguished with respect to the age of the leaves and the content of some metals. Young leaves were characterised by high levels of Zn and nitrogen whereas old leaves contained high levels of Fe and calcium, and both groups had moderate amounts of phenolics. Adult leaves were divided in two groups and results revealed that while one group had the highest levels of all phenols and lowest amounts of Mn and Cu, the other showed opposite quantities. The Canonical Correlation Analysis confirmed a highly significant negative correlation between phenol contents and Mn and Cu. These facts suggested that flavonoids and tannins production depends of the amounts of foliar nutrients, Cu and Mn in particular, which are cofactors of enzymes involved in phenol degradation and lignin biosynthesis. This knowledge can improve this specie cultivation in order to enhance the phenolic compounds concentration.

A new approach for quantifying furanodiene and curzerene: a case study on the essential oils of Eugenia uniflora L., Myrtaceae (pitangueira) leaves

The essential oil obtained from the leaves of Eugenia uniflora L., Myrtaceae, which grows in the Brazilian savannah, was studied by gas chromatography mass spectrometry (GC-MS). Furanodiene (1.2 percent) was thermally rearranged to curzerene (85.1 percent) to produce a combined content of 86.3 percent. GC analysis carried out under mild conditions (with a constant temperature of 100 ºC) showed that the furanodiene concentration was three-fold greater than the curzerene concentration, i.e., the essential oil contained 64.7 percent furanodiene and 21.6 percent curzerene. Germacrene B also rearranged to γ-elemene and the concentration of both was 2.3 percent. Special care should be taken when conventional gas chromatography analysis is used for quantifying compounds that can rearrange at high temperatures.

Seasonal variation in the phenol content of Eugenia uniflora L. leaves / Variação sazonal nos teores de fenóis de folhas de Eugenia uniflora L

Hydrolysable tannins, total phenols and flavonoids in Eugenia uniflora leaves were monthly analysed for one year. The results were correlated with climate conditions (rainfall, humidity, cloudiness and mean temperature) through chemometric methods. Principal component analysis revealed high levels of hydrolysable tannins in the rainy season, whereas flavonoids were mainly produced in the dry season. These facts suggest that climatic changes may be one of the factors affecting phenol levels in Eugenia uniflora.

Taninos hidrolisáveis, fenóis totais e flavonóides presentes em folhas de Eugenia uniflora foram quantificados mensalmente durante um ano. Os resultados foram correlacionados com as condições climáticas (pluviosidade, umidade, nebulosidade e temperatura média) através de métodos quimiométricos. Análise de componentes principais revelou a ocorrência de altos teores de taninos hidrolisáveis durante a estação de chuvas, enquanto os flavonóides foram produzidos principalmente na estação seca. Estes fatos sugerem que mudanças climáticas podem ser um dos fatores que afetam os níveis de fenóis em Eugenia uniflora.