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We investigated the phenolic composition, radical scavenging activity, and antimicrobial activity of grapevine leaf extracts from two red grape varieties, Vranac and Merlot (Vitis vinifera L.). The extracts were prepared from healthy grapevine leaves and those infected by Plasmopara viticola (downy mildew). The phenolic composition of the grapevine leaf extracts was determined using spectrophotometric assays and reverse-phase high performance liquid chromatography (RP-HPLC). The radical scavenging activity of grapevine leaf extracts was determined by the 2,2-diphenyl-1-picrylhydrazyl assay, and their antimicrobial activity was determined by microwell dilution tests. The total phenolic content was higher in healthy grapevine leaf extracts than in infected grapevine leaf extracts. The RP-HPLC analysis detected significant amounts of flavonols, phenolic acids, and flavan-3-ols, and small amounts of stilbenes in the grapevine leaf extracts. Compared with the infected grapevine leaf extracts, the healthy grapevine leaf extracts were richer in flavonols, phenolic acids, and flavan-3-ols, but had lower stilbenes contents. All extracts showed strong free radical scavenging activity, which was strongly correlated with the total phenolic content (R(2) = 0.978). The extracts showed a stronger antimicrobial activity towards Gram-positive bacterial strains than towards Gram-negative bacterial strains and yeast. The phenolic compounds in grapevine leaves were responsible for their strong radical scavenging and antimicrobial activities. Together, these results demonstrate that grapevine leaves have high nutritional value and can be used as a fresh food and to prepare extracts that can be used as additives in food and medicines.

Fruit is rich in different phenolic compounds which are recognized as potential natural medicaments and have been used in folk medicine for centuries. In order to evaluate phenol composition, cornelian cherry (Cornus mas) fruit and leaf extracts were subjected to the spectrophotometric and HPLC analysis. The radical scavenging activity was estimated using DPPH test and antimicrobial activity by disc diffusion and microwell dilution tests. All extracts showed high phenol content from 89.89 ± 0.45 to 117.34 ± 1.40 mg f gallic acid equivalents GAE/g extract dry matter DM but different composition of phenol compounds. Flavonols, anthocyanins, flavan-3-ols and phenolic acids were the main phenol classes found in the investigated fruit and leaf extracts. All extracts showed significant radical scavenging activity and a correlation with total phenol content (R2 = 0.9832). Significant antimicrobial activity was found against Gram-positive, followed by Gram-negative strains, and yeast in all tested extracts. Cornelian cherry fruit and leaf extracts, rich in phenolic content, with significant antiradical and antimicrobial activity, can be used as additives in food and medicaments. [Projekat Ministarstva nauke Republike Srbije, br. 34012, br. 31020 and br 176006 and EU, FP7 - Regpot - 2007- 3-01, the project «Chromlab-Antioxidant», No. 204756]

Periodontal disease is a chronic inflammatory disease, the pathogenesis of which involves different innate immune system as well as adaptive immune system cells, including macrophages. Macrophages are professional phagocytes whose primary role is ingestion and destruction of microorganisms. Apart from phagocytosis, these cells are engaged in production of proinflammatory cytokines and antigen presentation to T cells, and therefore are considered to be the key cells of the innate immune response. Our study focused on distribution and density of macrophages in healthy and inflamed gingiva with the purpose of evaluating their relevance to pathogenesis of periodontal disease. The material used for this purpose were gingival biopsies taken from 96 patients assorted in 4 groups: the healthy gingiva, gingivitis, moderate periodontal disease and severe periodontal disease. The immunohistochemical staining method based on the use of monoclonal antibodies anti-CD68 was used for identification of macrophages. Our study showed that the density of macrophages is higher in gingivitis and periodontal disease compared to healthy gigiva. There were no significant differences found regarding the density of macrophages in gingivitis and periodontal disease. Grouping of macrophage populations close to partially lysed collagen fibers in periodontal disease indicates their collagenic activity. The increase in the number of macrophages in inflamed gingival tissue could be linked to bone resorption due to the fact that these cells are capable of differentiating into osteoclasts.