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A sulfate-bridged complex [Cu(µ2-SO4)(Im)4] (1) was prepared and structurally characterized, where Im: imidazole. The X-ray structure analysis reveals that 1 crystallizes in the monoclinic system with space group C2/c. The octahedral coordination around the metal center is made up of four distinct imine nitrogen atoms in the equatorial plane, and two sulfate oxygen atoms occupying the axial sites. The covalent linkage between metals via the sulfate group, forming infinite 1D zigzag chains, ensures the entanglement of the structure. These chains, in turn, are further assembled into a 2D network through N-H...O hydrogen bonding. Thermal analyses underline the high thermal stability of our complex, which starts to decompose at 200 °C. The infrared spectrum confirms the results obtained from the crystallographic analysis. Optical studies reveal the presence of a hypsochromic effect noticed in the absorption and photoluminescence spectra. The synthesized compound was found to reduce both oxidative injury and histopathological features, which are associated with skeletal metastases as a result of malignant Walker 256/B breast cancer cells. peerReviewed

Leishmaniasis is a parasitic disease affecting millions of people in Africa, Asia, and South America. It is considered as a major public health problem causing morbidity and mortality worldwide. Actually, the luck of vaccines and effective and less expensive antileishmanial therapy, have oriented pharmacological researches on natural antileishmanial drugs from medicinal plants. Hence, the purpose of this work is to optimize extraction parameters such as the percentage of aqueous ethanol mixture, the temperature and the time through the ultrasound bath equipment using a Box–Behnken Design (BBD) for maximal antileishmanial activity extraction from Moringa oleifera leaves. The cytotoxicity of the optimum extract was evaluated on RAW 264.7 macrophage cell line. The synergism between M. oleifera optimal extract and amphotericin B was also investigated using checkboard method. The optimum extract exhibiting the highest percent inhibition of Leishmania major promastigotes (99.15 ± 0.34%) was obtained using 16%v/v ethanol, at 60 °C for 20 min. Interestingly, this extract showed the best IC50 value of 6.87 ± 0.32 and 9.31 ± 0.72 μg/mL against promastigote and amastigote forms, respectively with no cytotoxicity on macrophage cells Raw 264.7 (SI = 17.53). Moreover, this extract showed a synergistic effect with amphotericin B (FIC = 0.375). HPLC analysis showed that at least six phenolic compounds were identified. Resorcinol, luteolin7-O-glucoside and syringic acid were the most active ones against L. major with IC50 values 3.788 ± 0.48, 10.70 ± 0.59 and 13.41 ± 0.59 μg/mL, respectively. Rutin and ferulic acid were further identified and showed moderate antileishmanial activity with IC50 values 78.51 ± 1.09 and 89.34 ± 1.22 μg/mL, respectively. Kaempferol 3-O-rutinoside was less active with IC50 value 204.4 ± 1.63 μg/mL.

Cupressus sempervirens L. is largely used in traditional medicine as an antimicrobial agent. The present study investigated the antioxidant, antibacterial and antileishmanial activities of C. sempervirens organic extracts at different phenological stages. Antioxidant activity was determined by DPPH (2,2-diphenyl-1-picrylhydrazylradical) scavenging assay, ferric reducing power and total antioxidant capacity. The antibacterial activity was evaluated against five clinical strains by disk diffusion method and minimum inhibitory concentration (MIC). The antileishmanial activity was determined against promastigote and amastigote forms of Leishmania (L.) infantum and L. major. Results of antioxidant activity showed that methanolic extract from vegetative stage had the most important activity. The ethyl acetate extract of C. sempervirens from flowering stage was the most active against Bacillus cereus (ATCC 14579) and Staphylococcus aureus (ATCC 25923) with MIC of 100 μg/mL and 50 μg/mL, respectively. Interestingly, this extract exhibited high antileishmanial activity against promastigote form of L. infantum and L. major (IC50 = 1.47 and 2.8 μg/mL, respectively) and amastigote form (IC50 = 3.61 and 5.42 μg/mL, respectively). Furthermore, ethyl acetate extract showed low cytotoxicity on macrophage cells Raw264.7 with selectivity index of 34.15 and 17.93 for L. infantum and L. major, respectively. The identification by HPLC and HPLC-MSn of active extracts of C. sempervirens revealed that major compounds of methanolic extract from vegetative stage and ethyl acetate extract from flowering stage were cupressuflavone and amentoflavone. Based on these results, C. sempervirens extracts could be used as an alternative to chemical drugs for the treatment of oxidative stress and infectious diseases.

Vitis vinifera grape is a highly cultivated crop and solid wastes generated by the wine industry are largely under exploited. Plentiful studies have intended analyzing the polyphenolic content of grape seeds but characterization of non phenolic compounds is rather scarce. The present study aimed at the selective extraction of lipid, phenolic and aqueous phases from grape seed powder (GSP) in order to establish their intimate composition, as well as their antioxidant and chelating properties underlying partly their biological effects. Major non phenolic compounds identified in the lipid phase were glyceryl-monostearate and 2-monostearin whereas fructofuranose and sucrose were the most abundant in the aqueous phase. Among the most abundant compounds detected in the various phases, the polyphenol quercetin exhibited the best affinity and free binding energy towards the active site of the calcium-dependent protease calpain. Polyphenols likely constitute the bioactive part of GSP that should be exploited as safe modulators of intracellular signaling which is likely at the basis of their health beneficial effects. Nevertheless other compounds as lipids or sugars should be valorized along with polyphenols to improve their bioavailability into highly protected organs as brain or eye.

Bacterial resistance to antibiotics is a serious public health problem which is due to the immoderate and often inappropriate prescription of antibiotics. As a result, the exploitation of new bioactive molecules with limited or no side effects from natural sources and their adoption as a therapeutic alternative to synthetic molecules have become priorities. It is in this perspective that our study was undertaken with the objective was to investigate the phenological stage effect on the yield and chemical composition of essential oils extracted from Tunisian Eucalyptus (Eucalyptus globulus L.) aerial parts. The synergitic effect of this essential oil with conventional antimicrobials was also evaluated against nine pathogenic bacteria and Candida albicans ATCC 10231. The cytotoxicity of these combinations was tested on Vero cells. Gas chromatography–mass spectrometry analysis showed two different chemotypes depending on the growth stage which were characterized as 1,8-cineole (13.23%) at vegetative stage and p-cymene at full flowering (32.19%) and fructification (37.82%) stages. A predominance of monoterpene hydrocarbons (72.84%) during the fructification stage was detected with p-cymene (12.58%–37.82%) and α-pinene (10.41%–13.39%) as the determinants of this class. In relation to the phenological stage, Eucalyptus essential oil showed potent capacity to reduce stable free radical DPPH (IC50 up to 740 μg/mL) and moderate ability to reduce the concentration of iron ions (EC50 and IC50 up to 2 and 12 mg/mL, respectively). Eucalyptus globulus essential oil was active against the different bacterial strains especially during the vegetative and full flowering stages (MIC = 2 mg/mL) against Bacillus cereus ATCC 14579 and Enterococcus faecalis ATCC 29212. Candida albicans ATCC 10231 was more sensitive than bacteria during the fructification stage. The combination of Eucalyptus essential oil with ampicillin revealed a partial synergy effect toward Methicillin-resistant Staphylococcus aureus (FICI of 0.53). Nevertheless, an addition effect was recorded under the combination of amphotericin B and Eucalyptus essential oil. The cytototoxity activity showed that these associations enhanced cell viability and made Eucalyptus essential oil non toxic toward Vero cells. The results showed that the precious Eucalyptus oil in association with antimicrobial agents could be not only a promising alternative but also a potential molecular complex which is hardly recognizable by microorganisms.

The aim of this study was to identify peptides with antioxidant, antityrosinase and antibiofilm activities released from Vicia faba seed proteins hydrolysate. The hydrolysis pattern was performed with trypsin. Firstly, the obtained hydrolysate was fractionated by cation exchange chromatography and the fraction exhibiting the highest biological activity was then analyzed by reverse phase HPLC tandem mass spectrometry. After annotation by Peaks software (BSI, Canada) for de novo peptide sequencing, seven peptides were identified, mainly derived from storage proteins: legumin and vicilin. These peptides were further chemically synthesized to assess their antioxidant capacity, antityrosinase activity and antibiofilm ability against Pseudomonas aeruginosa PA14. Results showed that peptides P5, P6 and P7 identified as LSPGDVLVIPAGYPVAIK, VESEAGLTETWNPNHPELR and EEYDEEKEQGEEEIR respectively, displayed the highest DPPH radical scavenging activity (IC 50 = 0.25–1.9 mM). P5 was the only peptide able to chelate iron and reduce Fe 3+ to Fe 2+ . Furthermore, peptides P4 (GPLVHPQSQSQSN) and P6 were observed as potent tyrosinase inhibitors with IC 50 values of 1 and 0.14 mM respectively. P1, P5, P6 and P7 also showed interesting antibiofilm activity against Pseudomonas aeruginosa PA14 with MBIC 50 value ranged from 12 to 35 μM. Our data suggest that V. faba seed proteins hydrolysate could be potentially used as a source of natural bioactive peptides for cosmetic and pharmaceutical applications.

Introduction Despite the significant developments occurring in the treatment of cancer, multiple myeloma remains the second haematological deadly disease. The aim of this study was to investigate the antiproliferative and apoptotic activities of Olea europaea L. cv Chetoui leaf and stem extracts (OLE and OSE) on human myeloma cells, given that plant compounds provide antitumor drugs. Methods Anti-cancer activity was tested on U266 human multiple myeloma cell line using MTT and trypan blue assays. Cell cycle analysis, cell death mechanism, mitochondrial membrane potential levels and caspases activities were assessed in U266 cells using flow cytometry. The nuclear morphology of U266 cells was observed using Hoechst 33342 using fluorescent microscopy. Results Our data revealed that treatment with OLE and OSE induced anti-proliferative effects on U266 myeloma cells in dose and time dependent manner. The IC50 of OLE and OSE were 55 and 35 μg/mL, respectively after 48 h of exposure. Interestingly, cell cycle analysis showed significant decrease of U266 cells in G1 phase related to significant increase in sub-G1 population after 24 h of extract treatment. Moreover, OLE and OSE significantly induced apoptosis in U266 cell line after 24 h of treatment by inducing mitochondria dysfunctions and caspase 3/7 expression. Conclusion To our knowledge this is the first paper to be conducted on olive stem extract. Our study showed that OLE and OSE had potent anti-multiple myeloma properties. This work may form the basis for further investigation on olive extracts as potential therapeutic agent on multiple myeloma.

Essential oils (EOs) extracted from medicinal plants gained interest in research due to their potential effectiveness as antimicrobial compounds that can substitute chemical pesticides for treatment of plant derived foods. This study aims to use Tetraclinis articulata EO to control Botrytis cinerea pre- and post-harvest infection on tomato. Tetraclinis articulata EOs extracted at vegetative, flowering and fructification stages were rich in α-pinene (8.10–21.52%), β-caryophyllene (5.17–16.10 %) and caryophyllene oxide (5.57–6.83 %) with the main chemical classes were oxygenated monoterpenes (30.50–50.86 %) and monoterpene hydrocarbons (12.19–28.96 %). The in vitro antifungal activity of EOs against B. cinerea varied with the phenological stage, with the highest activity observed at flowering stage which used subsequently. The activity of α-pinene alone or mixed with bornyl acetate according to their natural proportions at 250 μg mL−1 totally inhibited B. cinerea conidia germination. The pulverization of EO on detached leaflets at 2 mg mL−1 reduced B. cinerea necrosis to 14.50 % in comparison to only infected leaflets 76.00 %. Tetraclinis articulata EO applied as preventive treatment on tomato plants under greenhouse conditions enhanced plants growth and reduced B. cinerea infection to 17.72 % in comparison to infected and non-treated plants 52.11 %. The EO applied at 100 μg mL-1 on tomato fruit reduced infection caused by B. cinerea by 64.01 %. Tetraclinis articulata EO constitutes a promising natural product to reduce B. cinerea infections on tomato in pre- and post-harvest conditions during storage and transport.

Biofilm formation by the pathogenic strain Candida albicans (C. albicans) is a crucial virulence factor on biotic and abiotic surfaces especially in medical devices. The present study investigated the effects of Cinnamomum verum and Thymus capitatus essential oils (EOs) and their combination with antifungal drugs on the development of biofilm and mature biofilm. The molecular mechanism of action was also investigated. Results showed that C. verum and T. capitatus EOs were broadly effective against C. albicans biofilm formation exhibiting 85.57% and 80.6% inhibition at half MIC values, respectively. Furthermore, they showed 92.79 and 94.46% eradication of C. albicans mature biofilm at 2xMIC values. Moreover, these EOs were able to reduce the production of secreted aspartic proteases by >90% at 0.75xMIC. The antibiofilm potency was improved when EOs were combined with AMB, effectively eradicating C. albicans mature biofilm on central venous catheter (CVC). Transcriptomic analyses indicated that EOs, especially when combined with AMB, down-regulate Ras-cAMP-Efg and MAPK signaling genes. In addition, EOs and their combination with AMB significantly inhibited the expression of adhesion and secreted aspartyl proteinase virulence factor genes. Our results demonstrated that C. verum and T. capitatus EOs and their combination with AMB could provide an effective treatment against C. albicans biofilm on medical devices.

Salt treatment strongly affected cell growth by decreasing dry weight. Exposure of Catharanthus roseus cell suspensions to increasing salinity significantly enhanced total lipid (TL) content. The observed increase is mainly due to high level of phospholipids (PL). Hundred mM NaCl treatment increased phospholipid species phosphatidylcholine (PC) and phosphatidylethanolamine (PE), whereas it reduced glycolipid ones monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) but not sulfoquinovosyldiacylglycerol (SQDG). Moreover, fatty acid composition was clearly modified when cells were cultured in the presence of 100 mM NaCl, whereas only few changes occurred at 50 mM. Salt treatment decreased palmitic acid (16:0) level and increased that of linolenic acid (18:2). Such effect was observed in phospholipid species PC and PE and in glycolipid DGDG. Double bond index (DBI) was enhanced more than 2-fold in fatty acids of either glycolipids or phospholipids from cells submitted to 100 mM NaCl. Free sterol content was also significantly enhanced, especially at 100 mM NaCl, whereas free sterols/phospholipids (St/PL) ratio was slightly decreased. All these salt-induced changes in membrane lipids suggest an increase in membrane fluidity of C. roseus cells.