BACKGROUND: Twenty-seven Italian honey samples of different floral origin were analysed for total phenolic and flavonoid contents by a spectrophotometric method and for antioxidant power and radical-scavenging activity by the ferricreducing/antioxidant power(FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays respectively. In addition, the phenolic and flavonoid profiles were analysed using high-performance liquid chromatography with UV detection (HPLC-UV). RESULTS: The results of this study showed that honey contains copious amounts of phenolics and flavonoids. HPLC-UV analysis showed a similar qualitative polyphenolic profile for all honey samples analysed. The main difference among samples was in the contribution of individual analytes, which was affected by floral origin. Total phenolic and flavonoid contents varied from 60.50 to 276.04 mg gallic acid equivalent kg(-1) and from 41.88 to 211.68 mg quercetin equivalent kg(-1) respectively. The antioxidant capacity was high and differed widely among samples. The FRAP value varied from 1.265 to 4.396 mmol Fe2+ kg(-1), while the radical-scavenging activity expressed as DPPH-IC50 varied from 7.08 to 64.09 mg mL(-1). Correlations between the parameters analysed were found to be statistically significant (P < 0.05). CONCLUSION: The present study shows that honey contains high levels of phenolics and flavonoids and that the distribution of these compounds is influenced by the honey's floral origin. (C) 2009 Society of Chemical Industr

In this work, the authors prepared and characterized two different graphene oxides: one chemically synthesized (GO sample) and the other one electrochemically synthesized (GO(LiCl)). Both samples were fully characterized with atomic force microscopy (AFM), Raman and Fourier transform infrared (FTIR) spectroscopies, X-ray photo electron spectroscopy (XPS), thermal analysis (TG/DTA), and Z-potential. The antibacterial properties of both graphene oxides were studied using Gram-negative Escherichia coli ATCC 25922 and Gram-positive Staphylococcus aureus ATCC 25923 by spectrophotometer and viable cell count as indirect and direct methods, respectively. Results demonstrated that the GO(LiCl) exhibited a significant antibacterial activity compared to GO that showed a bacteriostatic effect on both pathogens. Electron microscopy analysis confirmed the antibacterial effects of both graphene oxides toward the pathogens, especially working at 80 μg/mL, for 24 h. Additional studies were also performed and both GO samples were not cytotoxic at 2 μg/mL toward neuroblastoma cells. Moreover, 2 μg of GO was suitable to carry the minimum effective dose (5.74 ng/mL) of kinase inhibitor S29 (1-(2-chloro-2-(4-chlorophenyl)ethyl)-N-(4-fluorobenzyl)-1H-pyrazolo[3,4-d] pyrimidin-4-amine), providing negligible side effects related to the S29 treatment (this latter being specifically active on the neuroblastoma cell lines (SK-N-BE(2))).

-The aim of this work is to carry out a phytochemical analysis and biological screenings of vegetable extracts from Sida acuta and Malva sylvestris leaves, Castanea sativa and Eucalyptus camaldulensis pollen. Chemical analyses was focused on secondary metabolites, particularly phenolic compounds, which have several roles in the plant physiological processes and had demonstrated significant capacity in the prevention and care of human health diseases. Solid phase extraction (SPE) and analyses with liquid chromatography and mass spectrometry (HPLC-MS) allowed the identification of 5,7-dimethoxycoumarin, kaempferol, quercetin, genistein, apigenin and myricetin. Moreover, the M. sylvestris and S. acuta extracts demonstrated a cytotoxic activity on murine and human cancer cell lines by using a MTT assay.

Due to numerous episodes of contamination through illegal beekeeping practices, the certification and re-evaluation of honey is required to guarantee a clean, natural and healthy product. The aim of this work was to demonstrate the good quality of honey produced in protected areas by demonstrating both its nutraceutical content and its role in monitoring the plant species present in protected areas. All the physico-chemical parameters necessary for defining the quality of honey (botanical origin; conductivity; diastase activity; pH; free, lactonic and total acidities; water content; fructose, glucose and sucrose content; hydroxymethylfurfural) and total flavonoid and phenolic contents were analyzed and evidenced its high quality. Moreover, melissopalynology allowed us to establish a floristic census within the nature reserves and parks