Caffeoylquinic Acids, Cytotoxic, Antioxidant, Acetylcholinesterase and Tyrosinase Enzyme Inhibitory Activities of Six Inula Species from Bulgaria.

Chlorogenic (5-CQA), 1,5-, 3,5-, 4,5- and 3,4-dicaffeoylquinic (DCQA) acids were identified and quantified in the methanol extracts of Inula oculus-christi L., I. bifrons L., I. aschersoniana Janka var. aschersoniana, I. ensifolia L., I. conyza (Griess.) DC. and I. germanica L. by HPLC analysis. The amount of 5-CQA varied from 5.48 to 28.44 mg/g DE and the highest content was detected in I. ensifolia. 1,5-DCQA (4.05-55.25 mg/g DE) was the most abundant dicaffeoyl ester of quinic acid followed by 3,5-DCQA, 4,5-DCQA and 3,4-DCQA. The extract of I. ensifolia showed the highest total phenolic content (119.92±0.95 mg GAE/g DE) and exhibited the strongest DPPH radical scavenging activity (69.41±0.55 %). I. bifrons extract was found to be the most active sample against ABTS.+ (TEAC 0.257±0.012 mg/mL) and the best tyrosinase inhibitor. The studied extracts demonstrated a low inhibitory effect towards acetylcholinesterase and possessed low cytotoxicity in concentration range from 10 to 300 µg/mL toward non-cancer (MDCK II) and cancer (A 549) cells.

Furanocoumarin Content, Antioxidant Activity, and Inhibitory Potential of Heracleum verticillatum, Heracleum sibiricum, Heracleum angustisectum, and Heracleum ternatum Extracts against Enzymes Involved in Alzheimer's Disease and Type II Diabetes.

Hexane extracts of Heracleum verticillatum, H. sibiricum, H. angustisectum, and H. ternatum were studied for their furanocoumarin content antioxidant potential and acetylcholinesterase and α-amylase inhibitory activities. Quantification of the furanocoumarins was performed by 1 H-NMR. Pimpinellin was found to be the main component in the roots of all studied species. Bergapten and imperatorin were the major compounds in the fruits of H. sibiricum and H. verticillatum, respectively, while byakangelicol dominated in H. angustisectum and H. ternatum fruits. The leaf and fruit extracts of H. angustisectum demonstrated the highest DPPH radical scavenging activity and TEAC (IC50 0.58 mg/mL and 1.83 mm, respectively). The root extracts of H. verticillatum and H. angustisectum were found to be the most effective against acetylcholinesterase (IC50 0.30 and 0.34 mg/mL, respectively). The studied extracts were not active or demonstrated a weak inhibitory effect (%Inh. up to 29.7) towards α-amylase.

Phytochemical characterisation of Phlomis linearis Boiss. & Bal and screening for anticholinesterase, antiamylase, antimicrobial, and cytotoxic properties.

In the present work, essential oil and fatty acids and extracts obtained from aerial parts of Phlomis linearis Boiss. & Bal. were investigated for chemical composition and biological activities. The phytochemical analyses were conducted with gas chromatography-mass spectrometry/flame ionisation detector (GC-MS/FID) and liquid chromatography-mass spectromtetry (LC-MS/MS) techniques. The extracts and essential oil were studied for α-amylase and acetylcholinesterase activities with two different spectrophotometric methods. Antimicrobial activities of the extracts were investigated by microdilution. The extracts were evaluated in vitro for cytotoxic effects against cancer and normal cell lines by MTT assay. The essential oil (EO) contained α-pinene (12.5%) and ß-caryophyllene (10.7%) as main compounds. Palmitic (26.5%) and nonadecanoic acids (26.6%) were determined as fatty acids. Phytochemical analysis of the extracts found phenolic acids, phlinosides, verbascoside, and flavonoids. The extracts and essential oil demonstrated poor α-amylase inhibitory activity. The best acetylcholinesterase inhibitory activity was obtained for diethly ether extract of P. linearis (67.2 ± 3.4%) at 10 mg /mL concentration. Ethyl acetate extract found to be effective against Staphlococcus aureus at a minimum inhibitory concentration (MIC) of 156.26 µg/mL. Diethyl ether extract of P. linearis was active on A549 cell lines with an IC50 = 316 ± 4.16 µg/mL when compared with cisplatin IC50 = 24.43 ± 0.14 µg/mL. To the best of our knowledge, the present work is the first comprehensive report on anti-acetylcholinesterase, anti-α-amylase, and antimicrobial activities, as well as cytotoxic effects of P. linearis.

Phenolic profile and antioxidant, acetylcholinesterase, and tyrosinase inhibitor activities of Jurinea tzar-ferdinandii Davidov, an endemic plant of the Balkans / Perfil fenólico y actividad antioxidante, acetilcolinesterasa e inhibidora de tirosinasa de Jurinea tzar-ferdinandii Davidov, planta endémica de los Balcanes

The methanol extract of the Balkan endemic species Jurinea tzar-ferdinandii Davidov demonstrated weak antioxidant activity against DPPH• and ABTS+• and low inhibitory potential against acetylcholinesterase (8.3% Inh.) and tyrosinase (IC50 = 208 ± 8 µg/mL) enzymes. Phytochemical investigation of the extract led to isolation and identification of apigenin, luteolin, apigenin-7-O-glucoside, apigenin-4'-O-glucoside, apigenin-7-O-gentiobioside, luteolin-4'-O-glucoside, rutin, narcissin, chlorogenic and 1,5-dicaffeoylquinic acid. With exception of apigenin and rutin, all isolated compounds are reported for the first time in the representatives of genus Jurinea. The distribution of flavonoids was discussed from chemotaxonomic point of view.

El extracto de metanol de la especie endémica de los Balcanes Jurinea tzar-ferdinandii Davidov demostró una actividad antioxidante débil contra DPPH• y ABTS+• y un bajo potencial inhibidor contra las enzimas acetilcolinesterasa (8.3% Inh.) tirosinasa (IC50 = 208 ± 8 µg/mL). La investigación fitoquímica del extracto condujo al aislamiento e identificación de apigenina, luteolina, apigenina-7-Oglucósido, apigenina-4'-O-glucósido, apigenina-7-O-gentiobiósido, luteolina-4'-O-glucósido, rutina, narcissin, clorogénico y ácido 1,5- dicafeoilquinico. Con excepción de la apigenina y la rutina, todos los compuestos aislados se informan por primera vez en el género Jurinea. La distribución de flavonoides se discute desde el punto de vista quimiotaxonómico.