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Herein, upgraded chloroquine (CQ) derivatives capable of overcoming Plasmodium resistance and, at the same time, suppressing excessive immune response and risk of concurrent bacteremia were developed. Twelve new ferrocene-CQ hybrids tethered with a small azathia heterocycle (1,3-thiazolidin-4-one, 1,3-thiazinan-4-one, or 5-methyl-1,3-thiazolidin-4-one) were synthesized and fully characterized. All hybrids were evaluated for their in vitro antiplasmodial, antimicrobial, and immunomodulatory activities. Additional assays were performed on selected hybrids to gain insights into their mode of action. Although only hybrid 4a was more potent than the parent drug toward CQ-resistant Dd2 Plasmodium falciparum strain, several other hybrids (such as 6b, 6c, and 6d) manifested substantially improved antimicrobial and immunomodulatory properties. Interesting structure-activity relationship data were obtained, hinting at future research for the development of new multitarget chemotherapies for malaria and other infectious diseases complicated by drug resistance, bacterial co-infection, and immune-driven pathology issues.

In this research, the possibility of using Ca(OH)2 in the form of commercial hydrated lime as a catalyst for the methanolysis of refined rapeseed oil was evaluated. Characterization of unused catalyst was performed by SEM-EDS, laser diffraction, XRF, BET, XRD and TG/DTG methods, and vegetable oil was analyzed for physicochemical characteristics. Within methanolysis, the effects of catalyst loading, reaction temperature and reaction time on methyl ester yield, density and viscosity of biodiesel, as well as the possibility of catalyst reuse were investigated. The obtained results showed that hydrated lime is an efficient catalyst for transesterification of vegetable oil, whereby the use of 3 wt% of catalyst relative to oil weight, at temperature 60℃ and mixing rate 1000 rpm after 120 min of transesterification reaction achieved a yield of methyl esters 98.76%. With three reuses of hydrated lime, without intermediate washing and regeneration procedures, the yield of rapeseed oil methyl ester remained above 90%.

The interest in the study of the gut microbiome has grown exponentially. Indeed, its impact on health and disease has been increasingly reported, and the importance of keeping gut microbiome homeostasis clearly highlighted. However, and despite many advances, there are still some gaps, as well as the real discernment on the contribution of some species falls far short of what is needed. Anyway, it is already more than a solid fact of its importance in maintaining health and preventing disease, as well as in the treatment of some pathologies. In this sense, and given the existence of some ambiguous opinions, the present review aims to discuss the importance of gut microbiome in homeostasis maintenance, and even the role of probiotics, prebiotics, and symbiotics in both health promotion and disease prevention.

A new electroanalytical method for vitamin B1 determination, based on adsorptive chronopotentiometric stripping analysis and non-specific adsorption onto mercury film electrode, was developed and validated. Stripping chronopotentiograms showed a single well-defined oxidation wave corresponding to vitamin B1 at about − 0.43 V in citrate buffer pH 6.0. The most important experimental factors affecting the monitored electroanalytical response of vitamin B1 were investigated and optimised. Under the optimal experimental conditions, linear response of vitamin B1 was obtained in the concentration range of 5–50 mg dm−3, with the achieved limit of detection of 1.64 mg dm−3, and the limit of quantitation of 4.97 mg dm−3. A mean recovery of 97.1% and relative standard deviations of 3.75% were achieved. The developed electrochemical procedure was successfully applied for the determination of vitamin B1 in pharmaceutical products. The results of the proposed method were in good agreement with those obtained by parallel HPLC analyses, confirming an accuracy of the developed method.

Allspice (Pimenta dioica (L.) Merr.) fruit was used for the essential oil and ethanolic extract isolation in the present study. The essential oil was obtained by Clevenger-type hydrodistillation from allspice fructus with hydromodule 1:10 m/v during 180 minutes, while the ethanolic extract was obtained by reflux extraction at the boiling temperature with solvomodule 1:10 m/v during 120 minutes. The qualitative and quantitative composition of the essential oil was determined by GC/MS and GC/FID methods, respectively. The total phenolic and total flavonoid content in the extract was determined according to the Folin-Ciocalteu and aluminium chloride methods, respectively the antioxidant activity of allspice fructus essential oil and the extract was determined spectrophotometrically by DPPH assay and the antimicrobial activity using the microdilution method on the following microorganisms: two types of bacteria (Bacillus cereus, Salmonella spp.) and one yeast (Candida albicans), pairs of reference strains and their isolates. The obtained results proved the presence of 20 components in the essential oil, mainly oxygenated monoterpenes. The extract and essential oil have shown the best antioxidant activities after 20 and 60 minutes of incubation with EC50 values of 0.011 mg/cm³ and 0.023 mg/cm³, respectively. Both the essential oil and the extract have shown an inhibitory effect on all investigated microorganisms. Allspice ethanolic extract showed a better inhibitory effect on B. cereus and S. enterica (isolate and ATCC strains) than the essential oil. On the other side, allspice essential oil showed a better inhibitory effect on C. albicans strains. The results obtained indicate that both the essential oil and the extract isolated from allspice fructus are a good source of natural antioxidants and antimicrobial agents with potential applications in food and pharmaceutical industries as a safer alternative to the synthetic additives.

Kraft lignin was treated with subcritical water at moderate temperatures (120–220 °C) in different gas atmospheres, with the goal of optimizing its depolymerization under mild conditions. Lignin depolymerization was observed and compared using different homogeneous and heterogeneous catalysts in both nitrogen and carbon dioxide atmospheres. The most important treatment parameters for maximum lignin depolymerization and the highest yields of phenolic and other aromatic monomers were optimized. The influence of the process temperature, pressure, and time in both gas atmospheres was defined and optimized for maximum liberation of monomers into the aqueous phase. The yields of total phenols and other aromatics in the nitrogen atmosphere were the highest at 150 °C, whereas treatment in the carbon dioxide atmosphere required higher temperatures (200 °C) for a comparable efficiency. The effects of phenol addition as a capping agent in lignin depolymerization were observed and defined for both gas atmospheres. Phenol addition caused a remarkable increase in the total phenols content in the aqueous phase; however, it did not significantly affect the contents of other aromatics. The antioxidant properties of lignin hydrolysates obtained at different temperatures in different gas atmospheres were compared, correlated with the total phenols contents, and discussed, showing the promising potential of lignin hydrolysates obtained under mild subcritical water conditions.

Lettuce is one of the most common types of leafy vegetables in human diet that is grown worldwide. Narrow and very small seeds make its sowing very difficult, requiring a lot of time and labour. Also, plants produced by manual sowing are often characterized by uneven germination. Those problems could be prevented by sowing pelleted seeds which require the development of adequate pelleting technology. Absence of quality lettuce seeds in the Serbian market results in large amounts of imported pelleted seeds every year. The aim of this study was to develop a domestic pelleting procedure and examine its effects on seeds quality parameters, in order to provide seeds to local farmers at a more affordable price compared to imported commercial pelleted seeds. Pelleted and non-pelleted seeds of the Panukia F1 hybrid were compared in several quality characteristics (1000 seed weight, germination energy, germination percentage, seedling length) in laboratory and greenhouse conditions. There was no loss in seed quality with the pelleting process, although the seed weight increased 12-19 times. Pelleted lettuce seeds had very high germination energy and seed germination (97-98%). In greenhouse conditions, non-pelleted seeds sprouted unevenly in relation to pelleted seeds. These results confirm the advantages of sowing pelleted seeds in terms of uniform germination and development of lettuce plants, primarily due to the precision of mechanical sowing. By offering domestic pelleting lettuce seeds to the growers, the production process would be significantly improved and accelerated with the reduction of manual labour, and therefore the overall production cost Zelena salata je među najzastupljenijim vrstama lisnatog povrća u ljudskoj ishrani koja se uzgaja širom sveta. Nedostatak kvalitetnog semena zelene salate na srpskom tržištu uzrokuje uvoz velikih količina piliranog semena svake godine. Usko i veoma sitno seme otežava setvu i zahteva mnogo vremena i rada. Takođe, biljke proizvedene ručnom setvom semena često se odlikuju neujednačenim nicanjem. Ovi problemi mogu se sprečiti setvom piliranog semena što zahteva razvoj adekvatne tehnologije piliranja. Cilj ovog istraživanja bio je da se razvije domaći postupak piliranja semena zelene salete i da se ispita njegov uticaj na parametre kvaliteta semena kako bi se lokalnim poljoprivrednim proizvođačima obezbedilo seme po pristupačnijoj ceni u odnosu na uvozno pilirano seme. Pilirano i nepilirano seme hibrida Panukia F1 poređeno je u nekoliko parametara kvaliteta (masa 1000 semena, energija klijanja, procenat klijavosti, dužina ponika) u laboratorijskim uslovima i proizvodnim uslovima u stakleniku. Piliranje nije uticalo na gubitak kvaliteta semena iako je masa semena piliranjem povećana od 12 do 19 puta. Pilirano seme zelene salate imalo je veoma visoku energiju klijanja i klijavost semena (97-98%). U proizvodnim uslovima u stakleniku, nepilirano seme je nicalo neujednačeno u odnosu na pilirano seme. Ovi rezultati potvrđuju prednost setve piliranog semena u pogledu ujednačenijeg nicanja i razvoja biljaka, prvenstveno zbog preciznosti setve piliranog semena. Ponudom domaćeg piliranog semena zelene salate proizvođačima značajno bi se unapredio i ubrzao proces proizvodnje uz smanjenje ručnog rada, a samim tim i ukupnih troškova proizvodnje.

Salmonellae are a major global diarrheal diseases agent and are commonly found in a variety of foods. However, eggs appear to be one of the most important sources of infection ultimately leading to salmonellosis. Here we investigate a potential utilization of onion (Allium cepa L.) dry scales extracts and decoction for disinfection of eggshells contaminated with Salmonella enterica spp. Antimicrobial activity was screened by a microplate dilution method against 32 environmental and 1 reference Salmonella strains, at 106 and 103 CFU/ml starting cell concentration. Also, the efficacy of egg submersion treatment was tested. At high contamination level of 106 Salmonella cells per ml, extracts exhibited MIC and MBC values in the range of 0.08-2.50 mg/ml and 0.31-10.0 mg/ml, respectively. Ethanol extract had the most potent antibacterial activity followed by methanol, ethyl-acetate and acetone extracts. Pure decoction had MIC and MBC in the range of 250-500 mg/ml. When testing a lower level of contamination (103 CFU/ml) which is more similar to real life levels, MIC and MBCs were 8 to 14 times lower. Submersion of artificially contaminated eggs in ethanol extracts and decoctions resulted in the complete elimination of Salmonella after 8 minutes of exposure. Thus, a reduction of a minimum of 3.71 log units was achieved during the 8 minutes of treatment. Having in mind natural levels of Salmonella eggshell counts are far lower it can be implied that such treatment could be highly effective in practical application. Results show that tested onion dry scale decontamination solutions are an efficient, cost-effective and eco-friendly options for eggshell decontamination, and are especially promising for use in organic egg production.

The increasing resistance of Pseudomonas aeruginosa strains to used antibiotics is a big problem of modern medicine. Finding antimicrobial substances which will increase the effects of the antibiotic is necessary. Therefore, the aim of the present study was to evaluate the time-lapse activity of the basil and sage oils, to evaluate the effect of the combined oil against P. aeruginosa clinical isolates, and to determine the oils potential to enhance the activity of ciprofloxacin. The obtained growth curves showed a reduction in the number of bacterial cells in the range of 10.5-94% when basil oil was applied. In the case of sage oil, a higher reduction has been observed (48.5-100%). The basil oil achieved a synergistic interaction with ciprofloxacin in 8 isolates, while the same effect for sage/ciprofloxacin combination was observed in 6 isolates. An Indifferent effect was noticed in 64% of the tested isolates for basil/sage combination. These data showed potential benefits of the oils and ciprofloxacin combination therapy in the treatment of P. aeruginosa infections.

Background: Clostridioides difficile is the most common causative agent of antibiotic-acquired diarrhea in hospitalized patients associated with substantial morbidity and mortality. The global epidemic of CDI (Clostridioides difficile infection) began in the early 20th century with the emergence of the hypervirulent and resistant ribotype 027 strains, and requires an urgent search for new therapeutic agents. Objective: The aim of this study is to investigate the antibacterial activity of the three essential oils isolated from spice herbs (wild oregano, garlic and black pepper) against C. difficile clinical isolates belonging to 6 different PCR ribotypes and their potential inhibitory effect on the biofilm production in in vitro conditions. Results: Wild oregano essential oil showed strong inhibitory activity in concentrations 0.02-1.25 mg/mL and bactericidal activity in concentrations from 0.08 to 10 mg/mL. Garlic essential oil was effective in the concentration range of 0.02-40 mg/mL, and 0.16 -> 40 mg/mL. MIC and MBC for black pepper oil ranged from 0.04 to 40 mg/mL, and 0.08 -> 40 mg/mL, respectively. All the tested oils reduced in vitro biofilm production, with the best activity of oregano oil. Conclusion: Essential oils of wild oregano, black pepper and garlic are candidates for adjunctive therapeutics in the treatment of CDI. Oregano oil should certainly be preferred due to the lack of selectivity of action in relation to the ribotype, the strength of the produced biofilm and/or antibiotic-susceptibility patterns.(c) 2022 Elsevier Ltd. All rights reserved.

Inflammatory bowel diseases (IBM), such as Crohn's disease, and their common complications represent a global health challenge. Many pyrazole derivatives, such as the spasmolytic drug metamizole, have already found their place among the frequently used therapeutic agents. Alteration of the structure of established therapeutic drugs by introducing a ferrocene moiety was shown to be a promising way for the discovery of new drugs. Herein, two libraries of analogous ferrocenyl (1a-1j) and phenyl alkanols (2a-2j) containing a pyrazole core, among which 17 completely new structures, have been synthesized, and structurally and electrochemically characterized. These compounds, along with the aldehydes used for their synthesis, were tested in parallel for their antispasmodic, acetylcholinesterase-inhibitory, and antimicrobial activities to evaluate their potential as multitarget IBM drugs. The antispasmodic activity was investigated by assessing their effect on both the amplitude and number of spontaneous contractions of isolated rat ileum. Their antimicrobial effect was evaluated against a panel of Gram-positive and Gram-negative bacterial strains and fungi. It was found that several of the evaluated compounds displayed gastrointestinal smooth muscle relaxant activity, among them, 1-(1H-3-ferrocenyl-1-phenylpyrazol-4-yl)-3-methylbutan-1-ol (1d) showed a remarkable effect by superseding the activity of papaverine. Together with the fact that it represents one of the most antimicrobially active investigated compounds, 1d is a good candidate for further pharmacological evaluation as a multitarget drug for IBM. © 2021 John Wiley & Sons, Ltd.

Thirteen commercial essential oils were assessed for their possible inclusion in a mouthwash formulation based on their inhibitory effect against potentially pathogenic anaerobic oral bacterial isolates from subgingival plaque, and their cytotoxicity towards gingival cells. The essential oils, originating from species belonging to seven major aromatic plant families, were chosen to provide the necessary diversity in chemical composition that was analyzed in detail by GC and GC/MS. Multivariate statistical analysis, performed using the in vitro microbiological/toxicological assays and compositional data, revealed that the major components of the essential oils were probably not the main carriers of the activities observed. A formulation of 'designer' mouthwashes is proposed based on the selective action of certain essential oils towards specific bacterial isolates (e. g., Citrus bergamia vs. Parvimonas micra), and non-toxicity to gingival cells at antimicrobially active concentrations.

Pediatric infections still represent a leading cause of mortality in many developing countries. Since ancient times, traditional healing systems provided some herbal remedies to treat pediatric diseases, only in some cases validated by an evidence-based approach. Therefore, this review covers the herbal remedies in Iranian traditional medicine and aims to assess the potential of phytotherapeutics as safe and effective alternatives to conventional therapies for the treatment of pediatric infectious diseases. Notably, pediatric patients may also benefit from adjuvant therapy, i.e., combined treatment with herbal remedies and conventional therapies, to improve the efficacy of conventional drugs, decrease their adverse effects at the cell-tissue-organ-organism level and reduce the occurrence of microbial strains resistant to antibiotics. Therefore, traditional healing systems still represent an unlimited source of active ingredients to be tested in preclinical assays as well as in humans in terms of efficacy and safety.

Using the "chiral pool" approach, two modified total syntheses of the biologically active δ-lactone cleistenolide (1) have been achieved starting from d-glucose. These approaches also enabled the preparation of novel analogues and derivatives of natural product 1. The applied strategy for the synthesis of 1 involves: the initial degradation of the chiral precursor for a single C-atom, C2-fragment chain extension using Z-selective Wittig reaction, and the final δ-lactonization. All tested cleistenolide analogues displayed antimicrobial activity against a panel of nine microbial strains, most of them superseding the activity of cleistenolide itself, and, in some cases, coming close in value to the observed minimal inhibitory concentrations of chloramphenicol. Increased lipophilicity of the derivatives and the non-sterically congested conjugated lactone moiety were a prerequisite for analogues with high inhibitory activity against S. aureus and, in general, Gram-positive bacteria.

The interest in the study of the gut microbiome has grown exponentially. Indeed, its impact on health and disease has been increasingly reported, and the importance of keeping gut microbiome homeostasis clearly highlighted. However, and despite many advances, there are still some gaps, as well as the real discernment on the contribution of some species falls far short of what is needed. Anyway, it is already more than a solid fact of its importance in maintaining health and preventing disease, as well as in the treatment of some pathologies. In this sense, and given the existence of some ambiguous opinions, the present review aims to discuss the importance of gut microbiome in homeostasis maintenance, and even the role of probiotics, prebiotics, and symbiotics in both health promotion and disease prevention.

Cardiovascular diseases (CVD) compromises a group of heart and blood vessels disorders with high impact on human health and wellbeing. Curcumin (CUR) have demonstrated beneficial effects on these group of diseases that represent a global burden with a prevalence that continues increasing progressively. Pre- and clinical studies have demonstrated the CUR effects in CVD through its anti-hypercholesterolemic and anti-atherosclerotic effects and its protective properties against cardiac ischemia and reperfusion. However, the CUR therapeutic limitation is its bioavailability. New CUR nanomedicine formulations are developed to solve this problem. The present article aims to discuss different studies and approaches looking into the promising role of nanotechnology-based drug delivery systems to deliver CUR and its derivatives in CVD treatment, with an emphasis on their formulation properties, experimental evidence, bioactivity, as well as challenges and opportunities in developing these systems. This work was supported by CONICYT PIA/APOYO CCTE AFB170007. N. Martins would like to thank the Portuguese Foundation for Science and Technology (FCT–Portugal) for the Strategic project ref. UID/BIM/04293/2013 and “NORTE2020—Programa Operacional Regional do Norte” (NORTE-01-0145-FEDER-000012).

Beverages are very complex systems consisting of a variety of compounds. In addition to many essential nutritional components and biologically active molecules, beverages could contain some harmful substances. Among undesirable compounds, metabolites of microbial origin such as biogenic amines and mycotoxins represent one of the greatest concerns, owning to their harmful effect on human health and their frequent occurrence in beverages. Biogenic amines are low-molecular-weight organic bases which are predominately formed by the decarboxylation of their particular precursor amino acids. High concentrations of those compounds are mainly found in fermented foods and beverages as a result of an uncontrolled microbial activity. Biogenic amines are essential for many functions in the human body, since they have powerful physiological effect and an important biological activity in low concentrations. However, if these compounds are consumed in high quantities, several toxicological problems arise. The consumption of foods containing elevated concentrations of biogenic amines may cause some detrimental effects such as headache, nausea, rash, giddiness, hypo-, or hypertension. Besides potentially toxicological effects, the presence of high concentration of BA in foods and beverages can been used as an indicator of undesired microbial activity, spoilage, and defective manufacturing processes. Mycotoxins are naturally occurring, toxic metabolites which can be produced by fungi in the different stages of processing and production of food and beverages. Generally, they are stable chemical compounds and cannot be destroyed during processing and heat treatment. When present in food and beverages in sufficiently high amounts, these fungal secondary metabolites can have adverse effects on human being. Acute intoxications range from skin irritation to immunosuppression, hepatotoxicity, and nephrotoxicity, while chronic exposures to some mycotoxins were shown to be mutagenic, teratogenic, and carcinogenic. In addition, the liver, kidney, nervous system, endocrine, and immune systems can be affected by those toxins. Because of potential harmful effect and toxicity, many countries have set up regulations for biogenic amines and mycotoxins control in food and beverages. In order to ensure adequate quality control and compliance with stipulated legislation, it is necessary to use reliable and accurate analytical methods for biogenic amines and mycotoxins determinations which allow unambiguous identification and quantitation at very low concentration. From technological point of view it is also important to monitor the presence of those substances, not only in final products, but also in raw materials during the production processes. The conventional methods of analysis of biogenic amines and mycotoxins normally require sophisticated instrumentation, mainly based on separation techniques. The aim of this chapter is to provide an overview on the methods presented in the literature for detection of substances of microbial origin in beverages, focusing on biogenic amines and mycotoxins.

The positive impact of probiotic strains on human health has become more evident than ever before. Often delivered through food, dietary products, supplements, and drugs, different legislations for safety and efficacy issues have been prepared. Furthermore, regulatory agencies have addressed various approaches toward these products, whether they authorize claims mentioning a disease’s diagnosis, prevention, or treatment. Due to the diversity of bacteria and yeast strains, strict approaches have been designed to assess for side effects and post-market surveillance. One of the most essential delivery systems of probiotics is within food, due to the great beneficial health effects of this system compared to pharmaceutical products and also due to the increasing importance of food and nutrition. Modern lifestyle or various diseases lead to an imbalance of the intestinal flora. Nonetheless, as the amount of probiotic use needs accurate calculations, different factors should also be taken into consideration. One of the novelties of this review is the presentation of the beneficial effects of the administration of probiotics as a potential adjuvant therapy in COVID-19. Thus, this paper provides an integrative overview of different aspects of probiotics, from human health care applications to safety, quality, and control.

Plant species have long been regarded as possessing the principal ingredients used in widely disseminated ethnomedical practices. Different surveys showed that medicinal plant species used by the inhabitants for the traditional treatment of diseases are inadequately screened for their therapeutic/preventive potential and phytochemical findings. The genus Nepeta L., which belongs to the family Lamiaceae, are widely used in traditional medicine. In this review, Nepeta species, which are used as traditional herbal medicine pursued indigenously, have reported several pharmacological effects as antimicrobial, antioxidant, antiinflammatory, sedative, relaxant, cholesterol lowering, antiasthmatic, carminative, diuretic, diaphoretic, febrifuge, vermifuge, herbicidal, insecticidal and insect repellent, all of them directly related to the specific chemical composition. According to the Nepeta genus phytochemistry, there exist two main essential oil chemotypes. The first is the nepetolactone chemotype, and the second is the 1,8-cineole and/or linalool chemotype. The active constituents from Nepeta genus may provide the opportunity for the production of antidepressive, antidiabetes, analgestic, anti-inflammatory, lipid-lowering and cardioprotective drugs. Due to the effects of Nepeta species on improving the complications of various diseases, the need for doing more extensive and comprehensive clinical trials for the use of Nepeta species in the treatment of diseases is necessary. Recommended future directives incurring the design and conduct of comprehensive trials are pointed out to validate the usefulness of these active plant species and bioactive secondary metabolites either alone or in combination with existing conventional therapies.

Pathogens from the genus Salmonella belong to the group of the most common food poisoning causative agents. The present paper investigated the effect of the basil and rosemary essential oils as well as their combination on the growth of Salmonella enterica subspecies enterica serovar Enteritidis (Salmonella Enteritidis) in chicken meat, together with their spoilage protective potential at the two storage temperatures. Food model experiments included investigation of their effect to accompanying microbial flora on fresh meat, while anti-salmonella activity was evaluated on artificially inoculated raw and thermally processed meat. The tests were performed in two storage conditions, +4 °C (usual meat storage temperature) and +18 °C (room temperature, which favors the spoilage of investigated meat samples and development of food pathogens). Beside evaluation of microbiological status, physico chemical tests relevant as meat quality indicators (pH, colour, texture, thiobarbituric acid, cooking loss), as well as sensory evaluation of the studied meat samples were performed. Changes in normal flora pointed to significant effect of both oils against microbial meat spoilage, where various groups were affected by different treatments. In addition, all the treatments reduced the number of salmonella cells in comparison to the control samples. Obtained results on the physico-chemical parameters highlight their applicative value since they showed either beneficial effect either did not caused any notable meat quality changes.

Many Eryngium species have been traditionally used as ornamental, edible or medicinal plants. The gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC–MS) analyses have shown that the major compounds in the aerial parts were spathulenol (in E. campestre and E. palmatum oils) and germacrene D (in E. amethystinum oil). The main compounds in the root oil were nonanoic acid, 2,3,4-trimethylbenzaldehyde and octanoic acid for E. campestre, E. amethystinum and E. palmatum, respectively. All the oils expressed the highest potential against Gram-positive bacteria Staphylococcus aureus as well as Gram-negative Klebsiella pneumoniae and Proteus mirabilis. Molecular docking analysis was used for determining a potential antibacterial activity mechanism of compounds present in the essential oils. Molecular docking confirmed that the binding affinity of spathulenol to the active site of tyrosyl-tRNA synthetase was the highest among the tested dominant compounds. Regarding the total phenolic content (determined by the Folin–Ciocalteu assay) and flavonoid content (evaluated using aluminum nitrate nonahydrate), the highest amount was found in the ethyl acetate extract of E. palmatum. The results of DPPH and ABTS assay indicated that the highest antioxidant activity was present in the water extract of E. amethystinum. Extracts of the aerial parts presented as minimum inhibitory concentration (MIC) expressed the activity in the range 0.004–20.00 mg/mL, with the highest activity exhibited by the acetone and ethyl acetate extracts against Proteus mirabilis. The obtained results suggest that Eryngium species may be considered a beneficial native source of the compounds with antioxidant and antimicrobial properties.

In this paper, a chronopotentiometric method for the determination of herbicide metamitron (MTM) using a glassy carbon electrode (GCE) and a thin film mercury electrode (TFME) as working electrodes is presented. MTM provided a well-defined reductive peak in the Britton-Robinson buffer on both working electrodes. Instrumental and chemical factors such as pH of the buffer, initial potential and reduction current influencing MTM chronopotentiometric response were optimised with the Box-Behnken experimental design. Under the optimal combination of factors, the analytical signal was linear in the MTM concentration range of 0.8-30mg/L, with a detection limit of 68.53 mu g/L using a TFME, and in the concentration range of 1-30mg/L, with a detection limit of 92.91 mu g/L using a GCE. The precision of the method was estimated as a function of repeatability and reproducibility, with the value of relative standard deviation lower than 2.6%. The applicability of the method was verified by direct analysis of MTM in spiked water samples and commercial pesticide formulations. The obtained results were in good agreement with those obtained using liquid chromatography/tandem mass spectrometry (LC-MS/MS) method, or with those labelled by the manufacturer. By using chronopotentiometry, neither extraction nor preconcentration procedures are necessary, thus making this method simple, cost-effective and more feasible for analytical routine analysis.

Six gold(III) complexes with ligands of differing denticity, [HGly-Met sulfoxide][AuCl4] (1b), [Au(en)Cl2]Cl·2H2O (1c), [Au(dien)Cl]Cl2 (1d), [Au(Gly- l -His)Cl]NO3·1.25H2O (1e), [Au( l -Ala- l -His)Cl]NO3·2.5H2O (1f) and [Au(Gly-Gly- l -His)]Cl·H2O (1g), were synthesized and structurally characterized. These complexes, along with the starting compounds used for their synthesis, were tested for their immunomodulatory and antimicrobial activities. Immunomodulation was investigated by assessing their cytotoxicity towards mouse spleen lymphocytes and peritoneal macrophages. Their antimicrobial effect was tested against a panel of Gram-positive and Gram-negative bacterial strains including ATCC strains and resistant isolates. Antimicrobial potential of 1b-g was further explored by evaluating their antibiofilm activity against biofilm-forming Pseudomonas aeruginosa. All gold(III) complexes inhibited biofilm production of P. aeruginosa strains, where ethylenediamine-containing gold(III) complex 1c exhibited the strongest reduction of biofilms superseding the activity of the used antibiotic, leaving only 10% of biofilm unaffected. All investigated gold(III) complexes inhibited biofilm formation after 72 h of incubation, showing long-term effectiveness, which was visualized by microscopy during this time. The mode of antibiofilm action was evaluated by testing the effect of this complex on P. aeruginosa motility forms. Among the all investigated compounds, 1c possesses the highest both cytotoxic and antimicrobial action, making this complex a good candidate for further pharmacological evaluations.

Comparative analysis of the chemical composition and biological activity of the essential oils from the needles of four Pinus species (P. mugo subsp. mugo, P. nigra subsp. nigra, P. sylvestris and P. peuce) from the central Balkans was performed. Although different chemical profiles of the dominant terpenes for each species were determined, essential oils were, generally, dominated by monoterpenes with α-pinene as one of the first two major volatiles. Tested oils showed inhibitory action against respiratory pathogenic bacterial strains, isolated from human swabs, in the range of 1.25–20.00 mg/mL (MICs) and bactericidal effect (MBCs) at concentrations from 2.50 to 40.00 mg/mL. Considering cell wall composition, there were no significant differences in sensitivity between Gram-positive and Gram-negative strains. In addition, the place of isolation did not provide evidences for higher susceptibility/resistance of the strains obtained from the particular infection site. On the other hand, toxicity of essential oils towards developing Drosophila melanogaster larvae was low, except P. mugo subsp. mugo oil, which did not show any signs of toxicity at concentrations up to 3%. Highest mortality of larvae and adults of D. melanogaster was noted for P. sylvestris essential oil with an estimated LC50 at the end of experiment (14 days) of 2.78% with a 95% confidence interval of 2.15–3.42%. Short-term 96 h LC50 values due to low mortality at larval stage could not be calculated for any oil and are expected to be much higher than 3%. According to the obtained antimicrobial activity and toxicity towards D. melanogaster, the oils can be arranged in the following order: P. sylvestris > P. peuce > P. nigra subsp. nigra > P. mugo subsp. mugo.

The work presents results of the determination of metribuzin content in commercial pesticide formulations by applying chronopotentiometry with thin film mercury electrode as an electrochemical sensor. In the analyzed pesticide formulations, a single well defined reduction peak of metribuzin is observed at the potential around -880 mV. The content of the herbicide in commercial formulations is determined using the calibration curve method, by applying the initial potential of -0.21 V, and the final potential of -1.10 V. Recovery values based on the declared and found content of the active ingredient are in the range from 100.67% to 101.68%, with the values of relative standard deviation lower than 1.00%, indicating high accuracy and precision of the presented method. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III 46009]

Immortelle (Helichrysum italicum, Asteraceae) essential oil has been widely used in alternative medicine to accelerate wound healing, as well as in cosmetic products to stimulate skin regeneration and to reduce the appearance of wrinkles. It is also considered a natural and safe culinary spice that could also be applied in the food industry as a preservative in the future. The therapeutic efficacy of this oil changes with the natural variability of the composition. Herein we tested and mutually compared the antimicrobial and anti-inflammatory activities of four commercial immortelle oils differing in the relative amounts of marker compounds, i.e. neryl esters, α-pinene, γ- and ar-curcumenes, and β-diketones. The anti-inflammatory effect of selected chromatographic fractions, enriched in the aforementioned constituents, was evaluated by studying toxicity toward rat peritoneal macrophages, their nitric oxide production, myeloperoxidase, and arginase activities. Subsequently, the compositional and activity data were subjected to a multivariate statistical treatment to reveal the possible correlation(s) between the percentage of essential-oil constituents and the observed activities. The obtained results imply that immortelle oil efficiency as an antimicrobial and/or anti-inflammatory agent is most plausibly a result of a synergistic action between its constituents, and/or, rather unexpectedly, the presence of some minor constituents.

Neurotoxic thujones (α- and β-diastereoisomers) are common constituents of plant essential oils. In this study, we employed a statistical approach to determine the contribution of thujones to the overall observed behaviour-modulating and toxic effects of essential oils (Salvia officinalis L., Artemisia absinthium L., Thuja occidentalis L. and Tanacetum vulgare L.) containing these monoterpene ketones. The data from three in vivo neuropharmacological tests on rats (open field, light-dark, and diazepam-induced sleep), and toxicity assays (brine shrimp, and antimicrobial activity against a panel of microorganisms), together with the data from detailed chemical analyses, were subjected to a multivariate statistical treatment to reveal the possible correlation(s) between the content of essential-oil constituents and the observed effects. The results strongly imply that the toxic and behaviour-modulating activity of the oils (hundreds of constituents) should not be associated exclusively with thujones. The statistical analyses pinpointed to a number of essential-oil constituents other than thujones that demonstrated a clear correlation with either the toxicity, antimicrobial effect or the activity on CNS. Thus, in addition to the thujone content, the amount and toxicity of other constituents should be taken into consideration when making risk assessment and determining the regulatory status of plants in food and medicines.

A modified method for the analysis of nicosulfuron, rimsulfuron and prosulfuron was developed and validated by using microwave-assisted extraction (MAE) and ultra-performance liquid chromatography with diode array detection in the ultraviolet region (HPLC-UV-DAD). The most important experimental parameters of extraction procedure and HPLC-UV-DAD technique were optimised in respect to those sulfonylurea herbicides. High recoveries of the microwave-assisted extraction were obtained by using a dichloromethane–acetonitrile mixture (2:1 volume ratio) acidified with acetic acid (0.8 vol.%) with the addition of urea. The mean recoveries at three spiking levels ranged from 97.47 to 98.76% for nicosulfuron, 97.88 to 99.17% for rimsulfuron and from 97.91 to 99.83% for prosulfuron. The limits of detection of nicosulfuron, rimsulfuron and prosulfuron were 0.95, 0.91 and 0.89 μg kg–1, respectively. The accuracy of the developed method was confirmed by HPLC coupled with tandem mass spectrometry parallel analyses. The developed method was used to investigate the dissipation dynamics of sulfonylurea herbicides in the real field trials in Vojvodina Province, Serbia. The obtained half-lives were 0.05, 0.23 and 0.15 days for recommended dose application of nicosulfuron, rimsulfuron and prosulfuron, respectively. Low residues and short half-life in soil suggested that the risk to sensitive rotational crops after application of those sulfonylurea herbicides is low when they are used in the appropriate dosages. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 31072]

In the presented study, a comparative analysis of phenolic compounds, parallel with antioxidant and antimicrobial activity of selected plants from Spanish medicinal flora was conducted. Total phenolic content, flavonoid concentrantions, antioxidant activity and antioxidant capacity, as well as antimicrobial activity were determined for methanolic extracts from 21 medicinal or potential medicinal plants sampled from eight different locations on the teritory of Spain. The phenolic content, antioxidant properties and antimicrobial activity were determined for the first time for some analyzed species. Results for total phenolic content determined using Folin-Ciocalteu reagent and expressed in term of gallic acid equivalent, GAE (mg of GA/g of extract) ranged from 35.67 to 286.18 mg of GA/g of extract. The concentrations of flavonoids determined using spectrophotometric method with aluminium chloride and expressed in terms of rutin equivalent, RuE (mg of Ru/g of extract) ranged from 31.58 to 147.34 mg of Ru/g of extract. Antioxidant activity was determined using DPPH (1,1-diphenyl-2-picrylhydrazyl radical) reagent and was expressed as IC 50 (concentration of sample which is required to scavenge 50% of radicals), where values ranged from 123.80 to 14.77 μg/ml. Obtained results for antioxidant capacity evaluated using the Briggs-Rauscher oscillating reaction method ranged from 190.00 to 19.00 min. Antimicrobial activities of the studied methanol extracts were determined against three gram positive, three gram negative and two fungal strains using microdilution method. Investigated extracts exhibited variable activities with minimal inhibitory concentrations ranging from 0.01-20.00 mg/ml. A significant relation was noticed between the phenolic content, antioxidant activity analyzed through both methods and antimicrobial activity. High amounts of phenolics responsible for the good biological activity of the extracts from the tested plants is in connection with the local, zonal imposed habitat characteristics. The findings of our comparative study and interpretations of the obtained results promote the Mediterranean medicinal flora as an effective source of bioactive substances.

Piperine is the main compound present in black pepper, and is the carrier of its specific pungent taste, which is responsible for centuries of human dietary utilization and worldwide popularity as a food ingredient. Along with the application as a food ingredient and food preservative, it is used in traditional medicine for many purposes, which has in most cases been justified by modern scientific studies on its biological effects. It has been confirmed that piperine has many bioactive effects, such as antimicrobial action, as well as many physiological effects that can contribute to general human health, including immunomodulatory, hepatoprotective, antioxidant, antimetastatic, antitumor, and many other activities. Clinical studies demonstrated remarkable antioxidant, antitumor, and drug availability-enhancing characteristics of this compound, together with immunomodulatory potential. All these facts point to the therapeutic potential of piperine and the need to incorporate this compound into general health-enhancing medical formulations, as well as into those that would be used as adjunctive therapy in order to enhance the bioavailability of various (chemo)therapeutic drugs.