Halogenated boroxine K2[B3O3F4OH] (HB), an inorganic derivative of cyclic anhydride of boronic acid, is patented as a boron-containing compound with potential for the treatment of both benign and malignant skin changes. HB has effectively inhibited the growth of several carcinoma cell lines. Because of the growing interest in autophagy induction as a therapeutic approach in bladder carcinoma (BC), we aimed to assess the effects of HB on metabolic phenotype and autophagy levels in 5637 human bladder carcinoma cells (BC). Cytotoxicity was evaluated using the alamar blue assay, and the degree of autophagy was determined microscopically. Mitochondrial respiration and glycolysis were measured simultaneously. The relative expression of autophagy-related genes BECN1, P62, BCL-2, and DRAM1 was determined by real-time PCR. HB affected cell growth, while starvation significantly increased the level of autophagy in the positive control compared to the basal level of autophagy in the untreated negative control. In HB-treated cultures, the degree of autophagy was higher compared to the basal level, and metabolic phenotypes were altered; both glycolysis and oxidative phosphorylation (OXPHOS) were decreased by HB at 0.2 and 0.4 mg/mL. Gene expression was deregulated towards autophagy induction and expansion. In conclusion, HB disrupted the bioenergetic metabolism and reduced the intracellular survival potential of BC cells. Further molecular studies are needed to confirm these findings and investigate their applicative potential.

Chlorogenic acid, an ester of caffeic acid with quinic acid, also known as 5- O-caffeoylquinic acid (5-CQA), is a ubiquitous plant constituent that is an important intermediate in lignin biosynthesis. In some cases, it occurs at surprisingly high levels in the leaves and fruits of certain higher plants, such as coffee beans. Due to its catechol moiety and an extended side chain conjugation, it easily forms a resonance-stabilised phenoxy radical, accounting for its powerful antioxidant potential. The objective of this work was to determine if the esterification and methylation of 5- CQA would enhance its antioxidant activity. Two 5-CQA derivatives were prepared for this study. Chlorogenic acid was esterified with methanol over Amberlite IR120-H to obtain methyl chlorogenate, while methyl 3',4´-dimethyl chlorogenate was prepared from 5-CQA by treatment with diazomethane. Spectroscopic methods confirmed the structure of these derivatives. Their antioxidant properties were tested to establish a relationship between structure and antioxidant activity. Antioxidant activity results were generated for 5-CQA and its ester analogues using eight different methods. Depending on the method applied, results were expressed as IC50/MCE50 values or as equivalents of the applied standard (ascorbic acid and Trolox). In most of these tests, 5-CQA showed the highest antioxidant activity compared to its derivatives. Nevertheless, due to their hydrophobic characteristics, their ester analogues remain promising antioxidant candidates in emulsifying systems.

: Phenolic aldehydes and their derivatives found in nature are well-known for their potential biological activity. In this study, four 1-substituted 1,2,3,4-tetrahydroisoquinolines (THIQs) derived from phenolic aldehydes were synthesized by phosphate buffer mediated Pictet-Spengler reaction. All derivatives were chemically and structurally characterized by elemental CHN analysis and spectroscopic methods (IR, HR-ESI-MS, 1 H-and 13 C-NMR). 1-Substituted THIQs derived from 3,4-dihydroxybenzaldehyde and 4-hydroxy-3-methoxybenzaldehyde were described for the first time. In order to cover the diversity of the mechanistic approach, but also to establish the relationship between structure and activity, antioxidant activity was examined by five different in vitro methods, namely: neutralization and reduction of stable free radicals 2,2-diphenyl-1-picrylhydrazyl and radical cation derived from [(2,2´-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)], ferric reducing antioxidant power, oxygen radical absorbance capacity, and ability to chelate Fe(II) ions. In vitro inhibition of acetylcholinesterase (AChE) was examined by the Ellman's colorimetric method, while computer-simulated docking was used to reveal the preferred binding site and major interaction between AChE and THIQs. Antibacterial testing was examined using the agar well method and results were presented in the form of zones of inhibition (mm).

Abstract Anti-proliferative effects of halogenated boroxine – K2(B3O3F4OH) (HB) – have been confirmed in multiple cancer cell lines, including melanoma, but the exact mechanism of action is still unknown. This study aimed to determine its cytotoxic effects on human Caucasian melanoma (GR-M) cell growth in vitro as well as on the expression of cell death-related genes BCL-2, BECN1, DRAM1, and SQSTM1. GR-M and peripheral blood mononuclear (PBM) cells were treated with different HB concentrations and their growth inhibition and relative gene expression profiles were determined using the Alamar blue assay and real-time PCR. HB significantly inhibited cell growth of both GR-M and PBM cells but was even more effective in GR-M melanoma cells, as significant inhibition occurred at a lower HB concentration of 0.2 mg/mL. GR-M BCL-2 expression was significantly downregulated (P=0.001) at HB concentration of 0.4 mg/mL, which suggests that HB is a potent tumour growth inhibitor. At the same time, it upregulated BCL-2 expression in normal (PBM) cells, probably by activating protective mechanisms against induced cytotoxicity. In addition, all but the lowest HB concentrations significantly upregulated SQSTM1 (P=0.001) in GR-M cells. Upregulated BECN1 expression suggests early activation of autophagy at the lowest HB concentration in SQSTM1 cells and at all HB concentrations in PBM cells. Our findings clearly show HB-associated cell death and, along with previous cytotoxicity studies, reveal its promising anti-tumour potential.

In this study, the chemical composition and antioxidant activity of the hydrodistilled essential oil of Achillea lingulata, an endemic species of the Euro-Mediterranean region, originating from Bosnia and Herzegovina, was investigated for the first time. For comparison, an analysis of the essential oil of the widely distributed Achillea millefolium, which grows together in the same habitat, was made. Ninety-six components were identified in A. lingulata and A. millefolium oils comprising 97.8% and 85.8%, of the total oil, respectively. The oil of A. lingulata was characterized by a high content of oxygenated monoterpenes (76.8%). The main compounds were borneol (30.1%), trans-verbenol (15.5%), 2-tridecanone (12.2%), fragranol (8.3%), and myrtenol (7.9%). In contrast, essential oil of A. millefolium had oxygenated sesquiterpenes (60.8%) as the most abundant compounds, with elemol (32.9%) as the main constituent. In addition, γ-eudesmol (12.9%), caryophyllene oxide (7.7%), transcaryophyllene (5.7%) and γ-muurolene (4.7%) were present in a significant percentage in A. millefolium oil. Antioxidant activity was tested by three methods, ABTS, DPPH and FRAP, and the obtained results showed low activity of both investigated oils.

Volatile constituents of Satureja montana L. collected from a natural habitat in the southern region of Bosnia and Herzegovina were isolated by steam distillation and headspace sampling. The relative abundance of volatile compounds from the air-dried fragrant plant was analysed by GC-MS using two columns of different polarity. A total of 28 compounds were identified, constituting 93.5% of the essential oil composition. The GC pattern of headspace was different from that prepared by steam distillation. The former consisted of 14 compounds that made up 84.1% of the components identified. Both samples were dominated by oxygenated monoterpenes ranging from 55.2% for headspace of the plant material to 75.5% for the steam-distilled oil. Eleven alcohols represented the most diverse chemical class in the volatile oil (71.8%), as well as seven alcohols detected in the headspace (57.3%). GC-MS analysis of the volatiles indicates that S. montana belongs to linalool chemotype with its relative content of 38.7% for the essential oil and 23.7% for the headspace. With linalool as the most abundant constituent, the other major components were -terpineol (14.7%) in the essential oil, and cis-sabinene hydrate (21.8%) and p-cymene (17.9%) in the headspace sample. The results prove that the combined approach in the extraction of volatile compounds is reliable for the analysis of the aroma of complex herbal samples.

Volatile constituents of Satureja montana L. collected from a natural habitat in the southern region of Bosnia and Herzegovina were isolated both by steam distillation and headspace sampling. The relative abundance of volatile compounds from the air-dried fragrant plant was analysed by GC-MS using two columns of different polarity. A total of 28 compounds were identified, constituting 93.5% of the essential oil composition. The GC pattern of headspace was different from that prepared by steam distillation. The former consisted of 14 compounds that made up 84.1% of the components identified. Both samples were dominated by oxygenated monoterpenes ranging from 55.2% for headspace of the plant material to 75.5% for the steam-distilled oil. Eleven alcohols represented the most diverse chemical class in the volatile oil (71.8%), as well as seven alcohols detected in the headspace (57.3%). GC-MS analysis of the volatiles indicates that S. montana belongs to linalool chemotype with its relative content of 38.7% for the essential oil and 23.7% for the headspace. With linalool as the most abundant constituent, the other major components were terpineol (14.7%) in the essential oil, and cis-sabinene hydrate (21.8%) and p-cymene (17.9%) in the headspace sample. The results prove that the combined approach in the extraction of volatile compounds is needed for the analysis of the aroma of complex herbal samples.

Objectives: The global burden of the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the corona virus disease-19 (COVID-19) is enormous No definitive treatment and prophylactic guidelines for COVID-19 currently exist except for physical distancing and aerial barriers between individuals This work explored the natural compound-binding efficiency of SARS-CoV-2 proteins essential for host cell interaction and infection Methods: The binding activity of artemisinin to SARS-CoV-2 spike glycoprotein (Protein Data Bank (PDB) ID: 6VYB), SARS-CoV-2 main protease (3C-like main protease (3CLpro);PDB ID: 6Y84) and SARS-CoV-2 papain-like protease (PLpro;PDB ID: 6W9C), were tested using in silico methods Moreover, chloroquine and hesperidin were used as the positive control of binding affinity and proven therapeutic effect, respectively Results: The highest affinities for binding to all tested SARS-CoV-2 proteins are observed for hesperidin (-5 8,-10 0, and -8 1 kcal/mol), then for artemisinin (-4 8,-8 3, and -6 0 kcal/mol), and the lowest for chloroquine (-4 1,-8 2, and -4 8 kcal/mol) Artemisinin, hesperidin, and chloroquine had similar positioning toward targeted proteins at specific sites when these interactions were visualized Conclusion: This study shows that artemisinin has the potential to bind and inhibit the SARS-CoV-2 spike protein, the 3CLpro main protease, and PLpro proteinase similar to hesperidin and chloroquine that have been proven as antivirals in previous preclinical and clinical studies

In order to determine influence of extraction method on volatile oil composition of Artemisia annua L., steam distillation, hydrodistillation, organic solvent extraction, and headspace sampling have been applied. The relative abundance of volatile compounds from the odorous aerial parts of A. annua, obtained by different extraction techniques, was analyzed by GC-MS. Exactly fifty constituents were identified. The leaf and flower essential oil yield ranged from 0.9 to 2.3% (v/w). Oxygenated monoterpenes were predominant in all samples ranged from 42.6% for steam-distilled fraction of petroleum ether extract to 70.6% for headspace of plant material. Essential oils isolated by steam distillation and hydrodistillation indicate that A. annua belongs to artemisia ketone chemotype with its relative content of 30.2% and 28.3%, respectively. The principal constituent in headspace sample of plant material was also artemisia ketone (46.4%), while headspace of petroleum ether extract had camphene (25.6%) as the major compound. The results prove the combined approaches to be powerful for the analysis of complex herbal samples.