Ivana Carev

Chemical composition and evaluation of acetylcholinesterase inhibition and antioxidant activity of essential oil from Dalmatian endemic species Pinus nigra Arnold ssp. dalmatica (Vis.) Franco

In the present study, the chemical composition and biological activity (acetylcholinesterase inhibition and antioxidant activity) of essential oil from endemic species Pinus nigra Arnold ssp. dalmatica (Vis.) Franco was investigated. α-Pinene, β-pinene, germacrene D and β-caryophyllene were identified by GC-FID and GC-MS as dominant components of the oil. P. nigra ssp. dalmatica essential oil showed relatively high inhibitory activity on acetylcholinesterase (AChE), which can be in relation with good AChE inhibitory activity of pure main monoterpene components of the oil (S-α-pinene) and their mixtures (S-α-pinene:S-β-pinene and R-α-pinene:S-β-pinene, in ratio 3:2). Essential oil from P. nigra ssp. dalmatica did not show significant antioxidant activity tested by three methods: DPPH radical scavenging method, Ferric Reducing Antioxidant Potential (FRAP) and Thiobarbituric Acid Reactive Species (TBARS) assays.

Phytochemical and Cytogenetic Characterization of Centaurea solstitialis L. (Asteraceae) from Croatia

The cytogenetic characterization of Centaurea solstitialis L. (Asteraceae) showed a chromosome number of 2n = 16. Karyotype is composed by four pairs of metacentric, two pairs of submetacentric and two pairs of subtelocentric chromosomes. Physical mapping of two rDNA probes revealed two loci of 35S and one locus of 5S rRNA genes. Chromomycin fluorochrome banding revealed that all rDNA loci were GC rich. The genome size (2C‐value) of 1.95 pg classes this species in the group of very small genomes. Chemical composition of C. solstitialis volatile oil (VO) from Croatia, studied with gas chromatography–mass spectrometry showed dominant components as it follows: hexadecanoic acid, α‐linolenic acid, germacrene D and heptacosane. Antioxidant capacity, measured by ferric reducing power assay and 2,2‐diphenyl‐1‐picrylhydrazyl methods, as well as inhibition of acetyl‐ and butyrylcholinesterase of VO was lower comparing to a standard solutions. Volatile oil tested with disc diffusion method showed good inhibitory potential against Pseudomonas aeruginosa, Escherichia coli and all tested fungi: Candida albicans, Penicillium funiculosum and Aspergillus fumigatus. The microdilution method showed best activity against Chronobacter sakazakii and A. fumigatus.

Screening for acetylcholinesterase inhibition and antioxidant activity of selected plants from Croatia

The methanol, ethyl acetate and chloroform extracts of selected Croatian plants were tested for their acetylcholinesterase (AChE) inhibition and antioxidant activity. Assessment of AChE inhibition was carried out using microplate reader at 1 mg mL−1. Antioxidant capacities were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging test and ferric reducing/antioxidant power assay (FRAP). Total phenol content (TPC) of extracts were determined using Folin–Ciocalteu colorimetric method. Out of 48 extracts, only methanolic extract of the Salix alba L. cortex exerted modest activity towards AChE, reaching 50.80% inhibition at concentration of 1 mg mL−1. All the other samples tested had activity below 20%. The same extract performed the best antioxidative activity using DPPH and FRAP method, too. In essence, among all extracts used in the screening, methanolic extracts showed the best antioxidative activity as well as highest TPC.

Qualitative HPLC-DAD-ESI-TOF-MS analysis, cytotoxic and apoptotic effects of Croatian endemic Centaurea ragusina L. aqueous extracts

Centaurea ragusina L., an endemic Croatian plant species, revealed a good cytotoxic activity of aqueous extracts (AE) on human bladder (T24) and human glioblastoma (A1235) cancer cell lines. The chemical constituents were tentatively identified using high performance liquid chromatography HPLC‐DAD/ESI‐TOF‐MS in negative ionization mode. The main compounds of herba extract were sesquiterpene lactones: solstitialin A 3,13‐diacetate and epoxyrepdiolide; organic acid: quinic acid. The main compounds of flower extract were organic acids: quinic acid, citric acid, and malic acid; sesquiterpene lactone: cynaropicrin; phenolic compounds: chlorogenic acid and phenylpropanoid: syringin. The AE of C. ragusina were investigated for correlation of their effects on human bladder (T24) and human glioblastoma (A1235) cancer cell lines using the MTT assay. Although both extracts showed significant dose‐ and time‐dependent cytotoxic activity against both cancer cell lines, the flower extract exhibited slightly higher activity. In order to determine type of cell death induced by treatment, cell lines were exposed subsequently to a treatment with both flower and herba AE. The majority of the cells died by induced apoptosis treatment. Flower AE (26.25%), compared to a leaf AE (22.15%) showed slightly higher percentage of an apoptosis in T24 cells, when compared to a non‐treated cells (0.04%).

Campanula portenschlagiana Roem. et Schult.: Chemical and Antimicrobial Activities

The phytochemical profile and the antimicrobial effects of the volatile oil and the aqueous extract of Campanula portenschlagiana, a wild growing plant endemic to Croatia, were described. In the volatile oil, 53 compounds were identified by GC‐FID and GC/MS analyses. Diterpene alcohols constituted the major compound class with labda‐13(16),14‐dien‐8‐ol as the main compound. The aqueous extract was characterized by the total phenolic content. The antimicrobial potential of the volatile oil and the aqueous extract was evaluated against a diverse range of microorganisms comprising food‐spoilage and food‐borne pathogens. The volatile oil exhibited interesting and promising antimicrobial effects against the tested species, which were generally more pronounced against Gram‐negative bacteria. In addition, the inhibitory effect of this volatile oil was also evaluated against eleven extended‐spectrum β‐lactamase (ESBL)‐producing isolates. The results suggest that the C. portenschlagiana volatile oil might be used as antimicrobial agent against ESBL‐producing isolates and Gram‐negative bacteria.

Phytochemical Composition, Antioxidant Potential and Cholinesterase Inhibition Potential of Extracts from Mentha pulegium L.

The aim of this work was to perform the phytochemical analysis as well as antioxidant and anticholinesterase potential of hot water and methanolic extracts from Mentha pulegium L., Lamiaceae, wild growing in Bosnia and Herzegovina. It is a plant that is traditionally used in Bosnia and Herzegovina medicine to treat gastrointestinal and neurological disorders. By HPLC‐DAD analysis of tested extracts, 15 phenol compounds were identified and quantified. Rosmarinic acid was the most abundant compound in both extracts, followed by ellagic acid, eriodictyol, naringenin and chlorogenic acid. Both extracts were demonstrated good radical scavenging potential, reducing power and ability to inhibit lipid oxidation. The tested extracts also showed low ability to inhibit protein oxidation and low or no acetylcholinesterase and butyrylcholinesterase inhibition potential. The promising radical scavenging potential, reducing power and lipid protection potential of tested extracts indicates that the extracts of M. pulegium could be useful in preventing free radical linked diseases, as well as food protecting antioxidants.

Phytochemical Composition and Antioxidant Activities of the Essential Oil and Extracts of Satureja subspicata Vis. growing in Bosnia and Herzegovina

The phytochemical composition and the antioxidant activities of the essential oil, as well as methanol and hot water extracts of endemic Satureja subspicata Vis. growing in Bosnia and Herzegovina (BiH), were described. β‐Caryophyllene, cis‐β‐ocimene, and α‐pinene, identified by GC/MS and GC‐FID, were the dominant oil components. The major compound of both of extracts, identified by HPLC‐DAD, was rosmarinic acid. The analyzed essential oil showed moderate antioxidant activity. In this first report on the extracts of S. subspicata growing in BiH, the obtained results showed a high content of rosmarinic acid, as well as considerable amount of total phenols and flavonoids. Compared to the hot water extract, the methanol extract exhibits higher antioxidant potential, measured by DPPH and FRAP assay (IC50 = 0.45 g/l and 1879.43 equiv. Fe2+ μm), while the hot water extract showed higher potential in inhibition of linoleic acid oxidation (51.7% and 61.5% for 1 and 10 g/l). A good antioxidant potential of the tested extracts indicates their potential use as antioxidants, particularly for lipid protection, and partly explains the justification of the use of this plant in traditional medicine of BiH.