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•Phenolic profiling of propolis from different geographical regions of Croatia.•Significant differences in phenolic composition of the Croatian propolis discovered.•Synergy of LC-QQQ, ...LC-QTOF and chemometrics in propolis profiling demonstrated.
Propolis is a complex biological matrix consisting mostly of plant resins and waxes, and in a small proportion of the herbal secondary metabolites, phenols. Phenols are components that are responsible for biological activities of propolis, however, their qualitative and quantitative composition is strongly influenced by climate and vegetation. Although studies on profiling of propolis samples from different countries have been carried out for some time propolis from Croatia is still not characterized till now. Targeted liquid chromatography coupled to triple quadrupole (LC-QQQ), untargeted liquid chromatography coupled to quadrupole time-of-flight (LC-QTOF) and direct injection QTOF methods were developed and 56 propolis samples from different geographical regions of Croatia were analyzed. Results revealed that there is not only one expected type of propolis in the territory of Croatia; i.e. beside expected European "poplar" propolis another type can be distinguished. Principal component analysis (PCA) and Partial least squares Discriminant Analysis (PLS-DA) indicated that the phenolic content of propolis samples significantly changes under the influence of the Mediterranean, so the “European” propolis type mixes with the Mediterranean type on the Croatian coast, especially on the islands. For fast screening of propolis type, direct injection QTOF analysis demonstrated to be fast and reliable method, but for unambiguous identification of phenolic compounds, chromatographic separation is indispensable. This paper presents the findings from the first research on phenolic profiling of propolis from Croatia.
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.
The aim of our study is to characterize the phenolic composition of a rare unifloral variety of honey - mint (
spp.) honey. For this purpose, we performed standard physicochemical analyses, pollen analysis, determined total phenolic and flavonoid content, analysed antioxidant activity and performed qualitative and quantitative analyses of phenolic compounds for five mint honeys.
Our results indicate that mint honey samples have high phenolic content, expressed in gallic acid equivalents, from (76.7±0.6) to (90.1±1.1) mg/100 g, and flavonoid content, expressed as quercetin equivalents, from (6.7±0.6) to (12.5±0.8) mg/100 g. These honey samples also exhibit strong antioxidant activity, expressed as Trolox equivalents, from (33.6±2.8) to (51.3±1.2) mg/100 g and from (14.4±0.8) to (55.1±2.4) mg/100 g when analysed with DPPH and ABTS assays, respectively. Quantitative LC-MS/MS analysis revealed that the most abundant phenols in all samples were chrysin, apigenin and
-coumaric acid. Qualitative LC-MS/MS analysis identified the presence of kaempferide, diosmetin, acacetin and several caffeic acid derivatives.
Our study indicates that mint honey contains unique phenolic profiles, which likely contribute to its 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 product market.
The technological process of wine production affects its chemical composition and consequently its organoleptic properties. Therefore, innovative technologies in wine production are of great ...importance in the competitive wine market. The maturation of wine in underwater springs is a novel technological process that, except for adding an attractive appearance to the wine bottle, potentially influences the wine's chemical composition. Herein, we performed total phenolic and flavonoid content analysis, phenolic profiling, and determined antioxidant potential for Malvasia white wines matured in traditional cellars and in the Northern Adriatic underwater springs. The antioxidant potential and total phenol and flavonoid content did not show significant differences between the two wine maturation processes. However, LC–MS/MS quantitative analysis showed that wines matured in the underwater springs had significantly increased concentrations of naringenin and myricetin. Despite the lack of a significant difference in chemical composition measured by less sensitive spectrophotometric methods, the quantitative differences of phenolic compounds were persistent and, as such, are a stimulus for further development and optimization of new wine production technologies including wine maturation in underwater springs.
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 is to characterize autochthonous grape varieties Verdić, Mejsko belo, Jarbola, Divjaka and Brajkovac. In addition, we performed a molecular characterization of the corresponding Belica wines.
Firstly, the genetic origin and ampelographic and economic characteristics of five autochthonous grape varieties were determined. Standard physicochemical profiles and phenolic components of 12 wines from different producers were determined by liquid chromatography coupled to triple quadrupole mass spectrometer (LC-QQQ-MS). Fourier-transform infrared spectroscopy (FTIR) was used for determination of standard physicochemical parameters.
Ampelographic analysis, which includes the data on producing characteristics and cluster and berry composition of the varieties, revealed significant differences between the analysed grape varieties. Results of the physicochemical 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-MS 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.
The presented results give 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.
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 (
Mill.) honeydew honey (HS) and probiotic bacteria
on
serotype Typhimurium, a primary cause of foodborne illnesses. The effect of three different samples of fir honeydew honey on the growth of
in de Man, Rogosa and Sharpe (MRS) medium and the potential synergistic effect of HSs and
on the growth of
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
, while a concentration of 10% inhibits the growth
. The concentration of 5% of all three HS and
combined inhibits the growth of
Typhimurium in BHI broth. Fir honeydew honey showed potential prebiotic properties and antimicrobial activity, both of which can synergistically enhance the probiotic efficacy of
against
. Typhimurium To conclude, the combination of fir honeydew honey and
represents a successful combination against
Typhimurium and additional experiments are necessary regarding the mechanisms of their combined effect.
Monofloral honey is obtained from the nectar of single-source plants and has a higher market value due to its polyphenol content associated with its biological properties, especially its antioxidant ...capacity. In this work, advanced extraction techniques using microwave- (MAE) and ultrasound-assisted (UAE) extraction of phenolic compounds in monofloral honey were optimized and compared. Optimal parameters for MAE were an irradiation time of 15 min, a temperature of 60 °C, and a microwave power of 300 W, and for UAE, a sonication time of 10 min, a temperature of 35 °C, and an ultrasound amplitude of 60%. The extraction solvent used was 70% ethanol. In the extracts of different monofloral honey samples (mint, fennel, raspberry, lavender, sage, buckwheat, maroon, heaven) obtained at optimal MAE and UAE conditions, polyphenolic compounds were determined using UPLC-ESI/MS2 analysis and antioxidant capacity using ORAC, ABTS, and DPPH assays. The results showed that UAE was the more efficient technique for the extraction of total flavanones, flavones, hydroxycinnamic acids, and total phenols, and MAE for total flavonols and hydroxybenzoic acids. The antioxidant ORAC and DPPH capacity was higher for the extracts obtained with MAE, while the ABTS capacity was higher for those obtained with UAE.
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.
Pozadina istraživanja. Na sastav meda utječu botanički izvor i geografsko podrijetlo nektara iz kojeg je dobiven. Uniflorni medovi postižu veću tržišnu vrijednost od multiflornih zbog svoje ...specifične arome, koja je rezultat prisustva hlapljivih i fenolnih spojeva.
Eksperimentalni pristup. Svrha je našeg rada bila okarakterizirati fenolni sastav rijetke uniflorne sorte meda – meda od metvice (Mentha spp.). U tu svrhu smo proveli standardne fizikalno-kemijske analize i analizu peludi, odredili ukupne udjele fenola i flavonoida, ispitali antioksidacijsku aktivnost te kvalitativno i kvantitativno ispitali fenolne spojeve u pet uzoraka meda od metvice.
Rezultati i zaključci. Rezultati pokazuju da uzorci meda od metvice imaju velik udjel fenola, izražen u ekvivalentima galne kiseline, od (76,7±0,6) do (90,1±1,1) mg/100 g, te udjel flavonoida, izražen u ekvivalentima kvercetina, od (6,7±0,6) do (12,5±0,8) mg/100 g. Uzorci su također imali snažnu antioksidacijsku aktivnost, izraženu u Trolox ekvivalentima, i to prema metodi DPPH od (33,6±2,8) do (51,3±1,2) mg/100 g, a prema metodi ABTS od (14,4±0,8) do (55,1±2,4) mg/100 g. Kvantitativnim ispitivanjem pomoću spregnutog sustava tekućinske kromatografije i tandemske spektrometrije masa utvrđeno je da su najzastupljeniji fenoli u svim uzorcima bili krizin, apigenin i p-kumarinska kiselina, dok je kvalitativnom analizom pomoću istog sustava utvrđena prisutnost kemferida, diosmetina, akacetina i nekoliko derivata kafeinske kiseline.
Novost i znanstveni doprinos. U istraživanju smo pokazali da med od metvice ima jedinstven fenolni profil, koji pridonosi njegovoj prepoznatljivoj aromi i snažnom antioksidativnom djelovanju. Detaljan opis rijetkih sorti meda omogućava pčelarima veću vidljivost i lakši pristup zahtjevnom tržištu prirodnih proizvoda.
Pozadina istraživanja. Primorsko područje Hrvatske bogato je autohtonim sortama vinove loze. Mnoge od njih su gotovo napuštene, poput autohtonih sorti s područja grada Kastva (Hrvatska), koje se ...koriste za proizvodnju vina kastavska Belica. Stoga je svrha prikazanog istraživanja bila okarakterizirati autohtone sorte vinove loze Verdić, Mejsko belo, Jarbola, Divjaka i Brajkovac. Osim karakteristika sorti, provedena je i molekularna karakterizacija vina kastavska Belica.
Eksperimentalni pristup. Najprije su utvrđeni genetsko podrijetlo te ampelografske i gospodarske značajke pet autohtonih sorti grožđa. Standardni fizikalno-kemijski profili i fenolni sastojci iz 12 uzoraka vina različitih proizvođača određeni su tekućinskom kromatografijom spregnutom s trostrukim kvadrupolnim masenim spektrometrom (LC-QQQ-MS). Infracrvena spektroskopija s Fourierovom transformacijom (FTIR) korištena je za određivanje standardnih fizikalno-kemijskih parametara.
Rezultati i zaključci. Ampelografskom analizom podataka o strukturi grozda i bobice te proizvodnim karakteristikama, poput prinosa i broja grozdova, potvrđene su bitne razlike između analiziranih sorti grožđa. Rezultati fizikalno-kemijske analize vina kastavska Belica pokazuju da sva vina ispunjavaju uvjete potrebne za proizvodnju kvalitetnih i vrhunskih vina sa zaštićenom oznakom izvornosti (ZOI) u Hrvatskom primorju. LC-QQQ-MS analiza potvrdila je prisutnost različitih fenolnih sastojaka u vinima, gdje su najizraženiji fenolni spojevi bili flavonoidi iz skupine flavan-3-ol. Uzevši sve navedeno u obzir, rezultati pokazuju da se grožđe autohtonih sorti s područja Kastva može koristiti za proizvodnju vina vrhunske kvalitete. Time vino kastavska Belica dobiva dodatnu tržišnu vrijednost, zbog sve veće potražnje za autohtonim proizvodima.
Novost i znanstveni doprinos. Prikazani rezultati daju znanstveni uvid i osnovu za daljnje određivanje optimalne tehnologije uzgoja s ciljem iskorištavanja najboljih značajki svake sorte za proizvodnju vina poželjnih svojstava.
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