Echinacea purpurea microbiota: bacterial-fungal interactions and the interplay with host and non-host plant species in vitro dual culture.

Important evidence is reported on the antimicrobial and antagonistic properties of bacterial endophytes in Echinacea purpurea and their role in the modulation of plant synthesis of bioactive compounds. Here, endophytic fungi were isolated from E. purpurea, and the dual culture approach was applied to deepen insights into the complex plant-microbiome interaction network. In vitro experiments were carried out to evaluate the species specificity of the interaction between host (E. purpurea) and non-host (E. angustifolia and Nicotiana tabacum) plant tissues and bacterial or fungal endophytes isolated from living E. purpurea plants to test interactions between fungal and bacterial endophytes. A higher tropism towards plant tissue and growth was observed for both fungal and bacterial isolates compared to controls without plant tissue. The growth of all fungi was significantly inhibited by several bacterial strains that, in turn, were scarcely affected by the presence of fungi. Finally, E. purpurea endophytic bacteria were able to inhibit mycelial growth of the phytopathogen Botrytis cinerea. Bacteria and fungi living in symbiosis with wild Echinacea plants interact with each other and could represent a potential source of bioactive compounds and a biocontrol tool.

Lepidium meyenii (Maca) does not exert direct androgenic activities.

Maca is the edible root of the Peruvian plant Lepidum meyenii, traditionally employed for its purported aphrodisiac and fertility-enhancing properties. This study aimed at testing the hypothesis that Maca contains testosterone-like compounds, able to bind the human androgen receptor and promote transcription pathways regulated by steroid hormone signaling. Maca extracts (obtained with different solvents: methanol, ethanol, hexane and chloroform) are not able to regulate GRE (glucocorticoid response element) activation. Further experiments are needed to assess which compound, of the several Maca's components, is responsible of the observed in vivo effects.

Mediterranean food and health: building human evidence.

Adherence to a Mediterranean style diet affords protection from degenerative diseases such as cardiovascular disorders and cancer. Identification of the active constituents of the Mediterranean diet is crucial to the formulation of appropriate dietary guidelines. Also, research on the pharmacological properties of the "minor components" of this diet, eg vitamins and polyphenols, is very active and might lead to the formulation of functional foods and nutraceuticals. Even though in vitro data are plentiful, human studies are difficult to perform due to ethical and practical reasons. Yet, intervention trials represent the best approach to validate claims of healthful activities. This article reviews human evidence of the biological properties of olive oil and tomato constituents and illustrates a research approach by which the bioactive elements of a wild plant (Cynara cardunculus) are first studied in vitro to build biochemical evidence, then in vivo to obtain proof of their vasomodularoty activity.

The role of antioxidants in the mediterranean diets: focus on cancer.

The incidence of certain cancers in the Mediterranean area is lower than in other areas of the world (e.g. in northern Europe and the USA). As nutrition and dietary factors comprise one of the three major factors for human carcinogenesis, the hypothesis was formulated that the dietary profile of the Mediterranean diet, rich in antioxidants, might exert preventive actions. Alas, the vast majority of experiments to prove this hypothesis have been obtained in vitro, and most of the necessary information on the absorption, distribution and metabolism of oligonutrients is currently lacking. Yet, even though the exact role of antioxidants in the Mediterranean diet is yet to be fully established, data from observational studies are strong enough to reinforce the notion that a diet low in saturated fat and alcohol and rich in plant food and whole grain, such as the traditional Mediterranean diet, is associated with lower risk of cancer and should be actively promoted.