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Medicinal and aromatic plants (MAP) have been described as a source of phenolic compounds with potential as antioxidant, antiproliferative and antimicrobial agents. MAP from the Lamiaceae family (Origanum vulgare L., Thymus vulgaris L., Ocimum basilicum L., Salvia officinalis L., Melissa officinalis L., and MatricariachamomillaL.) were selected to perform a phytochemical and biological screening for their further exploitation as natural bioactive ingredients. The total content of phenolic compounds varied from 184.02 mg/g extract in M. officinalis to 17.97 mg/g extract in M. chamomilla. Caffeic and rosmarinic acids were the main phenolic acids found in the respective hydroalcoholic extracts. The extracts showed a promising antioxidant activity in vitro, being related the phenolic compositions of the extracts, furthermore, all extracts being able to combat lipid peroxidation in TBARS assays with an IC 50 under 26 μg/mL, moreover all the plant extract has prevented the oxidative haemolysis in OxHLIA assays at concentrations below 67 μg/mL in a Δt 60 min and under 118 μg/mL for a Δt 120 min. Regarding to the bactericidal and fungicidal action the plant extracts were able to inhibit growth against bacteria associated with food hazards, such as Salmonella typhimurium (MIC < 1) and Listeria monocytogenes (MIC < 1), regarding to fungicidal activity it can be highlighted the MIC values under to 0.25 for Aspergillus versicolor and Trichoderma viride. Overall, the selected Lamiaceae plants stood out as a source of active phytochemicals that can be used by different industries, such as food and cosmetics., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Hesperetin is the aglycone of citrus flavonoid hesperidin. Due to the limited information regarding hesperetin antimicrobial potential and emerging need for novel antimicrobials, we have studied its antimicrobial activity (microdilution assay), antibiofilm activity with different assays in two models (mono- and polymicrobial biofilm), and toxicity (MTT and brine shrimp lethality assays). Hesperetin inhibited growth of all Candida isolates (minimal inhibitory concentration, MIC, 0.165 mg/mL), while it’s inhibitory potential towards Staphylococcus aureus was lower (MIC 4 mg/mL). Hesperetin (0.165 mg/mL) reduced ability of Candida to form biofilms and moderately reduced exopolysaccharide levels in biofilm matrix. Effect on the eradication of 24 h old C. albicans biofilms was promising at 1.320 mg/mL. Inhibition of staphylococcal biofilm formation required higher concentrations of hesperetin (<50% inhibition with MIC 4 mg/mL). Establishment of polymicrobial C. albicans-S. aureus biofilm was significantly inhibited with the lowest examined hesperetin concentration (1 mg/mL) in crystal violet and CFU assays. Hesperetin toxicity was examined towards MRC-5 fibroblasts (IC50 0.340 mg/mL) and in brine shrimp lethality assay (LC50 > 1 mg/mL). Hesperetin is efficient in combating growth and biofilm formation of Candida species. However, its antibacterial application should be further examined due to the cytotoxic effects provoked in the antibacterial concentrations.

Herein, we report computational and experimental evaluations of the antimicrobial activity of twenty one 2,3-diaryl-thiazolidin-4-ones. All synthesized compounds exhibited an antibacterial activity against six Gram-positive and Gram-negative bacteria to different extents. Thus, the MIC was in the range of 0.008-0.24 mg/mL, while the MBC was 0.0016-0.48 mg/mL. The most sensitive bacterium was S . Typhimurium, whereas S. aureus was the most resistant. The best antibacterial activity was observed for compound 5 (MIC at 0.008-0.06 mg/mL). The three most active compounds 5 , 8 , and 15 , as well as compound 6 , which were evaluated against three resistant strains, MRSA, P. aeruginosa , and E. coli , were more potent against all bacterial strains used than ampicillin. The antifungal activity of some compounds exceeded or were equipotent with those of the reference antifungal agents bifonazole and ketoconazole. The best activity was expressed by compound 5 . All compounds exhibited moderate to good drug-likeness scores ranging from -0.39 to 0.39. The docking studies indicated a probable involvement of E. coli Mur B inhibition in the antibacterial action, while CYP51 inhibition is likely responsible for the antifungal activity of the tested compounds. Finally, the assessment of cellular cytotoxicity of the compounds in normal human MRC-5 cells revealed that the compounds were not toxic.

Background: Over the years, transition metal complexes have exhibited significant antimicrobial and antitumor activity. It all started with cisplatin discovery, but due to the large number of side effects it shows, there is a growing need to find a new metal-based compound with higher selectivity and activity on more tumors., Objectives: Two novel trans-palladium(II) complexes with organoselenium compounds as ligands, [Pd(L1) 2 Cl 2 ] (L1 = 5-(phenylselanylmethyl)-dihydrofuran-2(3H)-one) and [Pd(L2) 2 Cl 2 ] (L2 = 2- methyl-5-(phenylselanylmethyl)- tetrahydrofuran) were synthesized, in the text referred to as Pd-Se1 and Pd-Se2. Also, a structurally similar trans-palladium(II) complex, [Pd(L3) 2 Cl 2 ] (L3= 2,2- dimethyl-3-(phenylselanylmethyl)-tetrahydro-2H-pyran) was synthesized according to an already published work and is referred to as Pd-Se3. The interaction of synthesized complexes with DNA and bovine serum albumin was observed. Also, antimicrobial activity and in vitro testing, cell viability, and cytotoxic effects of synthesized ligands and complexes on human epithelial colorectal cancer cell line HCT-116 were studied. Molecular docking simulations were performed to understand better the binding modes of the complexes reported in this paper with DNA and BSA, as well as to comprehend their antimicrobial activity., Methods: The interactions of the synthesized complexes with DNA and bovine serum albumin were done using UV-Vis and emission spectral studies as well as docking studies. Antimicrobial activity was tested by determining the minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) using the resazurin microdilution plate method. Cytotoxic activity on cancer cells was studied by MTT test., Results: The Pd(II) complexes showed a significant binding affinity for calf thymus DNA and bovine serum albumin by UV-Vis and emission spectral studies. The intensity of antimicrobial activity varied with the complexes Pd-Se1 and Pd-Se3, showing significantly higher activity than the corresponding ligand. The most significant activity was shown on Pseudomonas aeruginosa. Under standardized laboratory conditions for in vitro testing, cell viability and cytotoxic effects of synthesized ligands and complexes were studied on human epithelial colorectal cancer cell line HCT-116, where Pd-Se2 showed some significant cytotoxic effects., Conclusion: The newly synthesized complexes have the potential to be further investigated as metallodrugs., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective of this systematic review was to establish whether and what invasive infections in humans were caused by Kocuria kristinae, and to evaluate outcomes of administered antibiotic treatment. MEDLINE, EBSCO, SCOPUS, SCINDEKS and GOOGLE SCHOLAR were systematically searched for primary case reports or case series describing invasive infections with K. kristinae. K. kristinae is a pathogen microorganism that could cause invasive infections of various tissues in patients of any age. Majority of the patients had K. kristinae isolated from blood. It was also found in peritoneal fluid, pus, sputum, synovial fluid, bile, fluid from abdominal abscess, throat swab, urine catheter tip and mid-stream urine. Antibiotic treatment was almost universally effective, with only one death reported. Susceptibility was highest to vancomycin, linezolid, rifampicin, teicoplanin, tigecycline, cefotaxime, ampicillin/sulbactam, minocycline and meropenem. Initial treatment of Kocuria kristinae infections should involve parenteral vancomycin in combination with some other antibiotic to which it is susceptible.

Objectives: The chemical composition, antimicrobial and synergistic effect, and cytotoxic activity of Citrus limon (lemon), Piper nigrum (green pepper) and Melaleuca alternifoila (tea tree) essential oils (EOs) were investigated., Methods: Chemical analyses of essential oils were tested by GC-FID and GC-MS spectroscopy. The antimicrobial activity assay was conducted using microdilution method against several oral bacteria and Candida spp. originating from the humans with oral disorders. The synergistic antimicrobial activity was evaluated using checkerboard method. The cytotoxicity evaluation of EOs was assessed using MTT test., Key Findings: Limonene (37.5%) and β-pinene (17.9%) were the major compounds in C. limon oil, β-pinene (34.4%), δ-3-carene (19.7%), limonene (18.7%) and α-pinene (10.4%) in P. nigrum oil and terpinen-4-ol (38.6%) and γ-terpinene (21.7%) in M. alternifolia oil. The broad-spectrum antimicrobial activity was achieved by tested three EOs, with C. limon oil being the strongest against bacteria and M. alternifolia oil strongest against fungi. The EOs demonstrated synergism; their combined application revealed an increase in antimicrobial activity. All tested essential oils showed lower cytotoxic activity in comparison with the positive control, and the obtained results confirmed a dose-dependent activity., Conclusions: The results of this study encourage use of tested EOs in development of a novel agent intended for prevention or therapy of corresponding oral disorders., (© 2017 Royal Pharmaceutical Society.)

A. mellea fruiting bodies collected from nature were chemically characterized and shown to be rich in carbohydrates (81.25 g per 100 g dw), ash, fat and proteins (8.84 g per 100 g dw, 1.97 g per 100 g dw and 1.81 g per 100 g dw, respectively). Mannitol was the main free sugar while malic acid was the most abundant organic acid. δ-Tocopherol was the dominant form of tocopherols with 42.41 μg per 100 g dw. Polyunsaturated fatty acids were predominant, followed by saturated and monounsaturated fatty acids. A methanolic extract prepared from these samples was tested for antioxidant, quorum sensing and antimicrobial assays, as well as for its cytotoxicity effects. The extract showed antimicrobial activity against all tested microorganisms, including Candida albicans. Furthermore, when tested at sub-MIC concentration, it showed reduction of virulence factors and biofilm formation against Pseudomonas aeruginosa. The extract also exhibited antioxidant activity and did not show toxicity against tumor and non-tumor cells. Due to the observed bioactive properties and compounds of the honey mushroom and its well-balanced nutrients, this mushroom emerges as an interesting functional food and a source of nutraceuticals with applications in different diseases based on antioxidant and antimicrobial effects.

Two novel Pd(II) complexes with 2-(phenylselanylmethyl)oxolane and 2-(phenylselanylmethyl)oxane as ligands were synthesized. The crystal and molecular structure of the complexes has been determined by single crystal X-ray diffraction. It turned out for both complexes that the two ligands are coordinated to Pd via Se atoms in a trans-fashion and the other two trans-positions are occupied by Cl ions. Detailed 1D- and 2D-NMR analyses revealed the existence of equilibrating trans-diastereomeric species differing in the configuration at four chiral centers (selenium and carbon) in the solution of the complexes. A computational study was also undertaken to assess the relative stabilities of the mentioned stereoisomeric species. The antimicrobial properties of the complexes were investigated against a series of human pathogenic bacterial and fungal strains. The complexes were shown to possess promising broad spectrum moderate antimicrobial activity that is more pronounced against fungal organisms. The noted activity could be completely attributed to the Pd(II) center, whereas the ligands probably mediate the transportation of a Pd(II) species across cell membranes., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Guided by the idea that the presence of a heterocyclic aromatic core and tyramine moiety, under the umbrella of a single molecular scaffold could bring interesting biological properties, herein we present synthesis, characterization, with two crystal structures reported, and biological evaluation of some tyramine derivates. Cytotoxic and antimigratory potential was addressed by using a colorectal cancer cell line as a model system. Although possessing no cytotoxic effects, two compounds have shown strong antimigratory potential in low doses, with no effect on healthy MRC‐5 cells. Evaluation of their antimicrobial activities suggested prominent antimicrobial activity, where Compound 4 outperformed streptomycin against Escherichia coli and Proteus mirabilis. Hormone‐dependent types of cancer, such as prostate, ovary, and breast, are highly dependent on human sex hormone–binding globulin (SHBG) blood levels. A molecular docking study has shown that 1 has high affinity to bind and therefore compete with natural steroids for the SHBG steroid‐binding site. DNA‐binding study have shown that 4 interacts with CT‐DNA in a groove‐binding mode. In silico ADME/T study revealed that all compounds have suitable physicochemical properties for oral bioavailability and druglikeness, while toxicity tests for 1, 4, and 6 suggested potential for mutagenicity (4, 6), hepatotoxicity (6), and skin sensation (1). [ABSTRACT FROM AUTHOR]

The medicinal properties of transition metal complexes are greatly influenced by the nature and physico-chemical features of the ligand present in the complex structure. Due to the unique biological properties of the organoselenium compounds reflected in the variety of pharmacological activities (such as antioxidative, antiviral, antimicrobial and anticancer), the last years have brought increased interest for their use as a ligands compounds in the design and syntheses of range of transition metal-based coordination compounds that have been explored as antitumor and antimicrobial agents. Our aim in this review is to provide the overview of an recent development of the transition metal complexes bearing organoselenium ligands in the structure that could be promising choice for the treatment of various diseases, particularly cancer and infective diseases. For this purpose, the complexes of Co, Ni, Cu, Zn, Ru, Pd, Pt, Au and Sn as the most explored examples will be included and discussed. [ABSTRACT FROM AUTHOR]

• Antimicrobial potential of rosmarinic acid confirmed towards 11 Candida strains and 13 bacterial pathogens. • Antibiofilm properties include inhibition of Candida attachment, eradication of established biofilms, moderate reduction of exopolysaccharide production. • Antimicrobial mechanisms include disturbance in mitochondria activity and cell membrane integrity, moderate reduction in protease production but not binding to ergosterol. Emerging antimicrobial resistance and side effects associated with antibiotics overuse are driving the need for the novel antimicrobial therapeutics with the natural compounds considered as an appealing alternative. Rosmarinic acid is abundantly present in medicinal plants. This study aimed to elucidate its possible role as an inhibitor of planktonic and biofilm microorganism growth, along with its antifungal mechanisms. In this study, rosmarinic acid showed promising anticandidal (MIC 0.1–0.2 mg/mL) and antibacterial (MIC 0.002->0.8 mg/mL) activity. To some extent it was able to prevent cell attachment and eradicate established biofilms. Rosmarinic acid antifungal mechanisms included reduction of mitochondrial activity, alteration in membrane integrity, and slight inhibition of protease production but not binding to ergosterol. Its antibiofilm activity was moderately linked to the reduction in exopolysaccharide production. Considering its wide antimicrobial and antibiofilm spectrum rosmarinic acid could be further explored as an antimicrobial agent along with range of medicinal plants with rosmarinic acid as the dominant compound. Nevertheless, rosmarinic acid could serve as the basis for the development of antimicrobials employing novel mechanisms of activity. [ABSTRACT FROM AUTHOR]

Artemisia absinthium L. (Asteraceae) is traditionally used for gastrointestinal ailments and disorders linked to numerous risk factors including microbial infections. We aimed to provide contemporary evidence for its ethnopharmacological use and determine its antimicrobial capacity and mode of action, cytotoxicity, and phenolic constituents. Ethnopharmacological survey was conducted using semistructured interviews. Antimicrobial and antibiofilm capacities were determined by microdilution/crystal violet assay, respectively. Modes of action tested include estimation of exopolysaccharide production (congo red binding assay) and interference with membrane integrity (crystal violet uptake and nucleotide leakage assay). Cytotoxicity was determined using crystal violet assay. Polyphenolic profiling was done by advanced liquid chromatography/mass spectrometry (UHPLC-LTQ OrbiTrap MS). Artemisia absinthium in Serbia is traditionally used for gastrointestinal disorders, among others. Further study revealed high antifungal capacity of herb ethanolic extract towards range of Candida species (MIC 0.5–1 mg/mL) along with promising antibacterial activities (MIC 0.25–4 mg/mL). Interference with membrane integrity could be observed as a possible antimicrobial mechanism. Antibiofilm potential can be considered as high (towards C. krusei) to limited (towards P. aeruginosa) and moderate based on reduction in exopolysaccharide content. In concentrations up to 400 µg/mL, no cytotoxicity was observed towards HaCaT and HGF-1 cell lines. Polyphenolic analysis revealed twenty-one different constituents. A. absinthium usage as a gastrointestinal ailment remedy has been confirmed in vitro by its antimicrobial capacity towards microorganisms whose presence is linked to the diseases and associated complications and noncytotoxic nature of the natural product. The observed activities could be attributed to the present phenolic compounds. [ABSTRACT FROM AUTHOR]