Botanical influence on phenolic profile and antioxidant level of Italian honeys.

Honeybees directly transfer plant compounds from nectar into honey. Each plant species possesses a specific metabolic profile, the amount and the typology of plant molecules that may be detected in honey vary according to their botanical origin. Aim of the present work was the spectrophotometrical determination of concentration ranges of simple phenols and flavonoids in 460 several Italian monofloral honeys, in order to individuate specific intervals of plant metabolites for each typology of honey. Moreover, an LC-MS analysis was performed to determine amount of various secondary metabolites in the samples, with the purpose to use them as potential molecular markers in support to honey melissopalynological classification. As plant molecules have a strong reducing power, the antioxidant activity of the honeys was evaluated by two antiradical assays, DPPH and FRAP. The free radical scavenging effect of each monofloral group was correlated to the concentration of simple phenols and flavonoids, with the aim to deduce the existence of possible relationships between these parameters. In conclusion, dark honeys (Castanea sativa, honeydew, Erica sp. and Eucalyptus sp.) appeared to be the richest in secondary metabolites and, consequently, showed higher antioxidant activity. However, all analyzed monofloral honeys showed to be good sources of antioxidants.

Metabolic and biological profile of autochthonous Vitis vinifera L. ecotypes.

Vitis vinifera L. is a plant species rich in phenolic compounds that are usually associated with the health benefits of wine and grape consumption in the diet. Anthocyanins, catechins, flavonol, phenolic acids and stilbenes are key molecular constituents of the Vitis berries, affecting the quality of grape products. The purpose of this work was to identify the metabolic profiles of 37 genetically certified V. vinifera Latial accessions. In particular, qualitative and quantitative analyses of specific secondary metabolites and total phenolic and tannin contents were performed by LC-MS and spectrophotometric analysis. In addition, since plant molecules are well-known for their free radical scavenging properties, the antioxidant effects of the sample extracts were evaluated through two different antiradical assays: DPPH and FRAP tests. Finally, a preliminary screening of the antiproliferative activity of each specimen on HCT-116 human colorectal cancer cells was conducted. All the results showed a great variety and amount of phenolic compounds in all accessions; moreover, we observed a significant correlation in the extracts between the metabolite concentration and bioactivity. Besides, some samples presented extraordinary biological effects, such as reduction of tumor cell growth not associated with cytotoxicity, supporting their use as possible future adjuvants for cancer therapy. In conclusion, the present research increased the scientific knowledge about Italian autochthonous vine ecotypes in order to valorize them and support their reintroduction in the local economic system.

Antioxidant extracts of African medicinal plants induce cell cycle arrest and differentiation in B16F10 melanoma cells.

African ethnomedicine is essentially based on the traditional use of vegetal extracts. Since these natural drugs have shown health giving properties, in the present study we increased further the scientific basis supporting these data. We investigated the effects, on murine B16F10 melanoma cells, of plant extracts that were directly obtained by a Cameroon 'traditional healer'. After a preliminary study on the antioxidant functions of these compounds, already abundant in literature, Moringa oleifera Lam., Eremomastax speciosa (Hochst.) Cufod and Aframomum melegueta K. Schum extracts were individually analyzed. We performed laboratory assessments on these medicinal preparations in order to clearly demonstrate their antineoplastic features. All the treatments caused in tumor cells a great reduction in growth and proliferation rate, cell cycle arrest, increase of p53, p21WAF1/Cip1 and p27Kip1 protein levels and induction of differentiation. These results, on the bioactivity and the biochemical characteristics of African plant extracts, may increase the comprehension of indigenous therapeutic practices and represent the first step for the individuation of new inexpensive and natural drugs able to prevent and contrast cancer onset.