Context:Papaver rhoeas L. (Papaveraceae) corn poppy, widely distributed in Turkey, is used to make a cough syrup for children, as a tea for disturbed sleep, for pain relief and as a sedative in folk medicine.Objective: Samples of P. rhoeas collected from eight different locations in Turkey and three from northern Cyprus were investigated for their alkaloid content and screened for their antimicrobial activities.Materials and methods: From the aerial parts of P. rhoeas samples, alkaloids were isolated by column and preparative thin-layer chromatography. The alkaloids were identified by comparing their spectral data (UV, IR and 1H-NMR) and TLC Rf values with those of authentic samples. The antimicrobial study was carried out by microbroth dilution technique against six strains of bacteria and three strains of fungi.Results: Twelve different alkaloids belonging to proaporphine (mecambrine), aporphine (roemerine), promorphinan (salutaridine), protopine (coulteropine and protopine) and rhoeadine (epiglaucamine, glaucamine, glaudine, isorhoeadine, isorhoeagenine, rhoeadine and rhoeagenine) groups were isolated. The most significant activity was observed with the alkaloid extract of P8 against Staphylococcus aureus with a MIC value of 1.22 μg/mL and against Candida albicans with a MIC value of 2.4 μg/mL.Discussion: The results indicate that P. rhoeas samples (P8 and P9), which contain roemerine as their major alkaloid, were the most active extracts.

Extrusion of drugs or drug-like compounds through bacterial efflux pumps is a serious health issue that leads to loss in drug efficacy. Combinatorial therapies of low-efficacy drugs with efflux pump inhibitors may help to restore the activities of such drugs. In this quest, natural products are attractive molecules, since in addition to their wide range of bioactivities they may inhibit efflux pumps. The current work repurposed the bioactive alkaloid roemerine as a potential efflux pump inhibitor. In Bacillus subtilis, both Bmr and BmrA, belonging to the major facilitator and the ATP-binding cassette superfamilies, respectively, were found to be inhibited by roemerine. Scanning electron microscopy and RNA-Seq analyses showed that it potentiated the effect of berberine. Growth rates and checkerboard assays confirmed the synergy of roemerine and berberine and that roemerine prevented berberine efflux by inhibiting Bmr. Transport assays with inverted membrane vesicles prepared from Escherichia coli overexpressing BmrA showed that increasing roemerine concentration decreased the transport of doxorubicin, the BmrA substrate, confirming that roemerine may also be considered as an inhibitor of BmrA. Thus, these findings suggest that conjugation of roemerine to substrates of efflux pumps, Bmr and BmrA, may help to potentiate the activity of their drug substrates.

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The essential oils obtained by hydrodistillation of Vitex agnus-castus L. (Verbenaceae) fruits collected from five different localities in Turkey [Zonguldak (S1), Edirne (S2), Balıkesir (S3), Muğla (S4) and Antalya (S5)] were analyzed by gas chromatography (GC) and GC/mass spectrometry (GC/MS). β-Caryophyllene (11%) and α-pinene (10%) were identified as major components in the oil of S1. The highest amount of bicyclogermacrene (22.1%) was detected in the essential oil of S2. The major components of the essential oil of S3 were 1,8-cineole (17.8%), sabinene (15.8%), (Z)-β-farnesene (13.5%) and bicyclogermacrene (12.1%). The essential oil compositions of S4 and S5 had similarities, both containing sabinene [12.1% (S4), 12.1% (S5)], 1,8-cineole [13.2% (S4), 11.8% (S5)], β-caryophyllene [12.7% (S4), 11.4% (S5)] and bicyclogermacrene [11% (S4), 12.1% (S5)] as major components.

Among the different families of plant alkaloids, (-)-roemerine, an aporphine type, was recently shown to possess significant antibacterial activity in Escherichia coli. Based on the increasing demand for antibacterials with novel mechanisms of action, the present work investigates the potential of the plant-derived alkaloid (-)-roemerine as an antibacterial in E. coli cells using microarray technology. Analysis of the genome-wide transcriptional reprogramming in cells after 60 min treatment with 100 μg/mL (-)-roemerine showed significant changes in the expression of 241 genes (p value <0.05 and fold change >2). Expression of selected genes was confirmed by qPCR. Differentially expressed genes were classified into functional categories to map biological processes and molecular pathways involved. Cellular activities with roles in carbohydrate transport and metabolism, energy production and conversion, lipid transport and metabolism, amino acid transport and metabolism, two-component signaling systems, and cell motility (in particular, the flagellar organization and motility) were among metabolic processes altered in the presence of (-)-roemerine. The down-regulation of the outer membrane proteins probably led to a decrease in carbohydrate uptake rate, which in turn results in nutrient limitation. Consequently, energy metabolism is slowed down. Interestingly, the majority of the expressional alterations were found in the flagellar system. This suggested reduction in motility and loss in the ability to form biofilms, thus affecting protection of E. coli against host cell defense mechanisms. In summary, our findings suggest that the antimicrobial action of (-)-roemerine in E. coli is linked to disturbances in motility and nutrient uptake.

Purpose: To evaluate the phenolic content and biological activities of Lycium barbarum fruits cultivated in Turkey. Methods: Phenolic compounds in the water and methanol extracts of the fruits were determined by liquid chromatography-mass spectrometry (LC-MS/MS). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging activities and ferric-reducing antioxidant power (FRAP) assays were used to evaluate the antioxidant potential of the fruits. The acetylcholinesterase (AChE) inhibitory activity of the fruits was evaluated by Ellman assay. Results: LC-MS/MS results showed that all the extracts contained phenolic compounds including flavonoids, phenolic acids, anthocyanins and polyphenols. Some anthocyanins, namely, cyanidin-3-Oglucoside, cyanidin chloride, pelargonin chloride, pelargonidin chloride, and pelargonidin-3-0-glucoside were identified in the fruits for the first time. Pelargonidin-3-O-glucoside and cyanidin-3-O-glucoside were the main anthocyanins in the water extract with levels of 119.60 ± 12.04 and 1112.25 ± 125.40 mg/kg, respectively. The results indicated that the extracts possessed good radical scavenging and ferric-reducing activities. Conclusion: The results show that Lycium barbarum cultivated in Konya is a good source of the phenolic compounds, and thus may be exploited for commercial production of the antioxidants.

Background and Aims: Stachys L. species, which are members of the Lamiaceae family, have long been applied for their therapeutic benefits especially to cure cough, infection, genital tumors, ulcers, inflammatory illnesses, and wounds in Anatolian traditional medicine. In the current study, various extracts prepared from the aerial parts of Stachys cretica subsp. bulgarica Rech.f. (SC), Stachys byzantina K. Koch (SB), Stachys thirkei K. Koch and were tested for their in vitro antioxidant, antibacterial, and anticandidal properties. Methods:The aerial parts of three Stachys species were sequentially extracted using n-hexane, chloroform, and methanol. Aqueous extracts of each sample was also prepared by infusion process. The total phenolic content of each extract was determined and the contribution of the biological activities in the samples was evaluated. To assess the antioxidant capacity, samples were studied using CUPRAC activity, DPPH• free radical scavenging, and FRAP methods. The antimicrobial activity of the extracts was tested against 7 bacteria and 3 yeast. Results:The infusion and methanol extract exhibited the strongest antioxidant potential and also had the highest percentage of phenolics among the studied extracts. The n-hexane extracts of all studied species showed considerable antifungal activity with MIC values ranging from 312.5-78.12 mg/L. Conclusion:According to our results, three Stachys species were found to be beneficial for their antioxidant and antimicrobial properties.