Virgin olive oils (VOOs) obtained from the fruits of Croatian autochthonous varieties Mašnjača and Krvavica were extensively characterized for the first time. Investigated oils were compared with the oil obtained from Italian variety Leccino, grown and processed under the same conditions. Headspace volatile profile, tocopherols, chlorophylls, carotenoids and total phenolic content, peroxide value, % acidity, K 232 , K 270 as well as antioxidant activity (DPPH) of the oils' hydrophilic fractions (HFs) including their phenolic composition were assessed by means of HS-SPME/GC-MS, HPLC-FL, HPLC-DAD and spectrophotometric methods, respectively. Most of the studied quality parameters varied between the cultivars. The main volatile compounds detected in all tested olive oils were the C6 compounds derived from polyunsaturated fatty acids through the lipoxygenase pathway. Krvavica oil was characterized by hexanal (8.8%-9.4%). Leccino oil contained the highest percentage of (E)-hex-2-enal (73.4%-74.0%), whereas 882(Z)-hex-3-enal (21.9%-25.0%) and (E)-hex-2-enal (27.6%-28.9%) dominated in Mašnjača oil. Leccino oil contained the highest amount of tocopherols (312.4 mg/kg), chlorophylls (7.3 mg/kg), carotenoids (4.2 mg/kg) and total phenols (246.6 mg/kg). The HF of Leccino oil showed the highest antioxidant capacity (1.3 mmol TEAC/kg), while the HFs of Mašnjača and Krvavica oils exhibited the activity of 0.5 mmol TEAC/kg.

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The volatile oils obtained from the leaves and flowers of the Croatian endemic plant Centaurea ragusina L. were evaluated for antimicrobial activity. The chemical compositions, determined by GC and GC-MS, were complex, with sesquiterpenes the most abundant class of compound. Nonterpene hydrocarbons were also identified in high quantities, while acids and ketones were found in high quantities only in the leaf volatile oil. Aldehydes, alcohols, esters and other compounds were identified in lower quantities. Antimicrobial effects of the volatile samples were investigated by using the disc diffusion and microdilution assays. They were found to inhibit a wide range of bacteria and fungi, causing in vitro growth inhibition at a concentration of 250 μg/mL. The volatile oils displayed great antibacterial potential with MIC values ranging from 16 to 128 g/mL against the Gram-positive bacteria Bacillus cereus, Clostridium perfringens, Enterococcus faecalis and Staphylococcus aureus, and lesser activity against the Gram-negative bacteria Cronobacter sakazakii, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, as well as fungal strains (MIC= 32-128 g/mL).

Virgin olive oils from the fruits of Croatian autochthonous varieties Oblica, Lastovka and Levantinka were characterized for the first time. Headspace volatiles were analyzed by HS-SPME/GC-FID/MS. The main volatiles were C6 compounds. The most abundant was (E)-hex-2-enal (62.60%-69.20%). (Z)-Hex-3-enal was not found in Lastovka oil, while Levantinka oil did not contain hexanal. Tocopherols, chlorophylls and carotenoids were determined by HPLC-FL. Levantinka oil was characterized by the highest α-tocopherol level (222.00 mg/kg). Total phenolic contents (TPs), as well as antioxidant activity (DPPH assay) of the oils hydrophilic fractions (HFs) were assessed by spectroscopic methods. The antioxidant activity of Oblica oil HF was the most pronounced (0.91 mmol TEAC/kg) and the HF contained the highest TPs amount (212.21 mg/kg). HFs phenolic composition was determined by HPLC-DAD. The main identified phenols were secoiridoids dominated in Oblica oil: decarboxymethyl ligstroside aglycone (p-HPEA-EDA up to 158.5 mg/kg), oleuropein aglycone (3,4-HPEA-EA up to 96.4 mg/kg) and decarboxymethyl oleuropein aglycon (3,4-DHPEA-EDA up to 93.5 mg/kg).

The compounds responsible for highly individual aroma profile of Coriandrum sativum L. honey were isolated by headspace solid-phase microextraction (HS-SPME; used fibers: A: polydimethylsiloxane (PDMS)/divinylbenzene (DVB) and B: divinylbenzene/carboxen/polydimethylsiloxane), as well as ultrasonic solvent extraction (USE; used solvents: A: pentane/Et2 O 1 : 2 (v/v) and B: CH2 Cl2 ) and analyzed by gas chromatography (GC) and mass spectrometry (MS). Unusual chromatographic profiles were obtained containing derivatives of linalool/oxygenated methoxybenzene. trans-Linalool oxide (11.1%; 14.6%) dominated in the headspace, followed by other linalool derivatives (such as cis/trans-anhydrolinalool oxide (5.0%; 5.9%), isomers of lilac aldehyde/alcohol (14.9%; 13.8%) or p-menth-1-en-9-al (15.6%; 18.5%)), octanal, and several low-molecular-weight esters. The major compounds in the solvent extracts were oxygenated methoxybenzene derivatives such as 3,4,5-trimethoxybenzyl alcohol (26.3%; 24.7%), methyl syringate (23.8%; 11.7%), and 3,4-dimethoxybenzyl alcohol (5.6%; 13.9%). Another group of abundant compounds in the extracts were derivatives of linalool (e.g., (E)/(Z)-2,6-dimethylocta-2,7-diene-1,6-diol (17.8%; 16.1%)). Among the compounds identified, cis/trans-anhydrolinalool oxides and 3,4,5-trimethoxybenzyl alcohol can be useful as chemical markers of coriander honey.