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Research background. The composition of honey is influenced by the botanical source and geographical area of the nectar from which it is derived. Unifloral honeys reach higher market value than multifloral honeys due to their specific aromas, which result from volatile and phenolic compounds. Experimental approach. The aim of our study was to characterize the phenolic composition of a rare unifloral variety of honey - Mentha spp. honey. For this purpose, we obtained standard physico-chemical analyses, pollen analysis, determined total phenolic and flavonoid content, analysed antioxidant activity and performed qualitative and quantitative analysis of phenolic compounds for 5 Menta spp. honeys. Results and conclusions. Our results indicate that Mentha spp. honeys have high phenolic content, ranging from (76.7±0.6) to (90.1±1.1) mg GAE/100 g and (6.7±0.6) to (12.5±0.8) mg QUE/100 g for flavonoid content. These honeys also exhibit strong antioxidant activity ranging from (33.6±2.8) to (51.3±1.2) mg TE/100 g and (14.4±0.8) to (55.1±2.4) mg TE/100 g when analysed using DPPH and ABTS assays, respectively. Quantitative LC-MS/MS analysis revealed that the most abundant phenols in all samples were chrysin, apigenin and p-coumaric acid. Qualitative LC-MS/MS analysis identified the presence of kaempferide, diosmetin, acacetin and several caffeic acid derivatives. Novelty and scientific contribution. Our study indicates that Mentha spp. honeys contain unique phenolic profiles, which likely contribute to their distinctive aroma and strong antioxidant activity. A detailed description of the rare honey varieties gives beekeepers greater visibility and easier access to the demanding natural products market.

Honey is a natural food consisting mainly of sugars, enzymes, amino acids, organic acids, vitamins, minerals and aromatic substances. In addition to specific organoleptic properties, honey also has other components that contribute to its nutritional and health value. Proteins, vitamins, minerals, organic acids and phenolic compounds, the most variable components of honey, are predominantly responsible for its strong bioactive effect. Honeydew honey is a less known type of honey with outstanding antimicrobial and antioxidant properties that also demonstrates prebiotic effects and can promote the growth of probiotic bacteria. Foodborne illnesses can be prevented by using probiotic strains in combination with prebiotics. The aim of this study was for the first time to determine potential synergistic antimicrobial effect of fir (Abies alba Mill.) honeydew honey (HS) and probiotic bacteria Lactiplantibacillus plantarum on Salmonella enterica serotype Typhimurium, a primary cause of foodborne illnesses. The effect of three different samples of fir honeydew honey on the growth of L. plantarum in de Man, Rogosa and Sharpe (MRS) medium and the potential synergistic effect of HSs and L. plantarum on the growth of S. Typhimurium in the Brain Heart Infusion (BHI) medium were examined. The results indicate that concentrations of 1 and 5% of all three HS samples stimulate the growth and metabolic activity of L. plantarum, while a concentration of 10% inhibits the growth of L. plantarum. The concentration of 5% of all three HS and L. plantarum combined inhibits the growth of S. Typhimurium in BHI broth. Fir honeydew honey showed potential prebiotic properties and antimicrobial activity, both of which can synergistically enhance the probiotic efficacy of L. plantarum against S. Typhimurium To conclude, the combination of fir honeydew honey and L. plantarum represents a successful combination against S. Typhimurium and additional experiments are necessary regarding the mechanisms of their combined effect.

Research background. Coastal region of Croatia is rich in autochthonous grape varieties. Many of them have been almost abandoned such as the autochthonous varieties of Kastav (Croatia), used for the production of the Kastavska Belica wine. Therefore, the rationale of the presented study was to characterize autochthonous varieties 'Verdić', 'Mejsko belo', 'Jarbola', 'Divjaka' and 'Brajkovac' grape varieties. In addition, we performed a molecular characterization of the corresponding Belica wines. Experimental approach. Firstly, for five autochthons grape varieties, their genetic origin and ampelographic and economic characteristics were determined. Standard physico-chemical profiles and phenolic components by use of liquid chromatography coupled to triple quadrupole mass spectrometer (LC-QQQ) were determined for 12 corresponding wines from different producers. Fourier-transform infrared spectroscopy (FTIR) was used for determination of standard physico-chemical parameters Results and conclusions. Ampelographic analysis, which includes the data on producing characteristics and cluster and berry composition of varieties, revealed significant differences between analysed grape varieties. Results of physico-chemical analysis of the Belica wine showed that all wines met the requirements needed for the production of quality and top quality wines labelled with protected designation of origin (PDO) in Croatian coastal region. The LC-QQQ analysis confirmed the presence of different phenolic components in the Belica wines, where the most prominent phenols were flavonoids from the flavan-3-ol group. Overall, these results showed that autochthonous grapes from the Kastav region can be used for production of wines with added market value due to a growing demand for autochthonous products on the global market. Novelty and scientific contribution. The presented results represent scientific insight and a basis for further determination of the optimal cultivation technology aimed to take advantage of the best characteristics of each variety for production of a wine with desirable features.