Antimicrobial Activity of Catechol-Containing Biopolymer Poly[3-(3,4-dihydroxyphenyl)glyceric Acid] from Different Medicinal Plants of Boraginaceae Family.

This study reports the antimicrobial activities of the biopolymers poly[3-(3,4-dihydoxyphenyl)glyceric acid] (PDHPGA) and poly[2-methoxycarbonyl-3-(3,4-dihydroxyphenyl)oxirane] (PMDHPO), extracted from the six plants of Boraginaceae family: Symphytum asperum (SA), S. caucasicum (SC), S. gr and iflorum (SG), Anchusa italica (AI), Cynoglosum officinale (CO), and Borago officinalis (BO) collected in various parts of Georgia. The study revealed that the antibacterial activities were moderate, and biopolymers from only three plants showed activities against all tested bacteria. Biopolymers from CO stems as well as SC and AI did not show any activity except low activity against a resistant P. aeruginosa strain, which was the most resistant among all three resistant strains. On the other hand, the antifungal activity was better compared to the antibacterial activity. Biopolymers from BO stems exhibited the best activities with MIC/MFC at 0.37-1.00 mg/mL and 0.75-1.5 mg/L, respectively, followed by those from SG stems. Biopolymers from SC and AI roots showed antifungal activities against all six fungi, in contrast to the antibacterial activity, while biopolymers from CO stems and SA roots had activities against four fungi and one fungus, respectively. The sugar-based catechol-containing biopolymers from BO stems demonstrated the best activities among all tested biopolymers against T. viride, P. funiculosum, P. cyclpoium var verucosum, and C. albicans (MIC 0.37 mg/mL). In addition, biopolymers from SG stems were half as active against A. fumigatus and T. viride as ketoconazole. Biopolymers from all plant materials except for CO stems showed higher potency than ketoconazole against T. viride. For the first time, it was shown that all plant materials exhibited better activity against C. albicans, one of the most dreadful fungal species.

Antimicrobial activity of Annona muricata leaf oleoresin.

Bioactive compounds extracted from plants such as antimicrobials have attracted the attention of consumers and the food industry. This study aimed to determine the antimicrobial activity and chemical composition of Annona muricata leaf oleoresin obtained by supercritical CO2 extraction. The oleoresin was obtained by supercritical CO2 extraction and the chemical identification by gas chromatography coupled to mass spectrometry. Antimicrobial activity was evaluated by broth microdilution method against 14 foodborne fungi and bacteria. The oleoresin major chemical class was phytosterols (22.7%) and the major compounds were γ-sitosterol (15.7%), α-tocopherol (13.7%), phytol (13.1%), and hexadecanoic acid (11.5%). Minimum inhibitory concentration against bacteria ranged from 0.0025 to 0.010 mg mL-1. The oleoresin had high bactericidal activity against all bacteria, mainly Enterobacter cloacae and Pseudomonas aeruginosa with 0.005 mg mL-1 minimum bactericidal concentration. However, it had low fungicidal activity. The leaf oleoresin of A. muricata has promising applications in food, cosmetic, and pharmaceutical industries.

Chromenol Derivatives as Novel Antifungal Agents: Synthesis, In Silico and In Vitro Evaluation.

Herein we report the synthesis of some new 1H-1,2,4-triazole functionalized chromenols (3a-3n) via tandem reactions of 1-(alkyl/aryl)-2-(1H-1,2,4-triazole-1-yl) with salicylic aldehydes and the evaluation of their antifungal activity. In silico prediction of biological activity with computer program PASS indicate that the compounds have a high novelty compared to the known antifungal agents. We did not find any close analog among the over 580,000 pharmaceutical agents in the Cortellis Drug Discovery Intelligence database at the similarity cutoff of 70%. The evaluation of antifungal activity in vitro revealed that the highest activity was exhibited by compound 3k, followed by 3n. Their MIC values for different fungi were 22.1-184.2 and 71.3-199.8 µM, respectively. Twelve from fourteen tested compounds were more active than the reference drugs ketoconazole and bifonazole. The most sensitive fungus appeared to be Trichoderma viride, while Aspergillus fumigatus was the most resistant one. It was found that the presence of the 2-(tert-butyl)-2H-chromen-2-ol substituent on the 4th position of the triazole ring is very beneficial for antifungal activity. Molecular docking studies on C. albicans sterol 14α-demethylase (CYP51) and DNA topoisomerase IV were used to predict the mechanism of antifungal activities. According to the docking results, the inhibition of CYP51 is a putative mechanism of antifungal activity of the novel chromenol derivatives. We also showed that most active compounds have a low cytotoxicity, which allows us to consider them promising antifungal agents for the subsequent testing activity in in vivo assays.

Anthocyanin-rich extracts from purple and red potatoes as natural colourants: Bioactive properties, application in a soft drink formulation and sensory analysis.

Aqueous extracts from seven coloured potato varieties (three red-fleshed, three-purple fleshed, and one marble-fleshed) were studied for their anthocyanin content, in vitro biological activities, colouring properties and their potential application in the food industry. Acylated glycosides or pelargonidin and petunidin aglycones were identified as the main anthocyanin forms in the red and purple varieties, respectively. The total anthocyanin content among varieties ranged from 478.3 to 886.2 mg/100 g extract. All the extracts presented in vitro antioxidant, antibacterial and antifungal activities, whereas no toxic effects were detected. Finally, two selected extracts were tested as colourants in a soft drink formulation and presented suitable sensory profiles as well as high colour stability during a 30-day shelf-life when compared with the commercial colourant E163. Therefore, the tested extracts could be used as natural food colourants and considered for substituting the existing synthetic colouring agents.

Antioxidant Extracts of Three Russula Genus Species Express Diverse Biological Activity.

This study explored the biological properties of three wild growing Russula species (R. integra, R. rosea, R. nigricans) from Serbia. Compositional features and antioxidant, antibacterial, antibiofilm, and cytotoxic activities were analyzed. The studied mushroom species were identified as being rich sources of carbohydrates and of low caloric value. Mannitol was the most abundant free sugar and quinic and malic acids the major organic acids detected. The four tocopherol isoforms were found, and polyunsaturated fatty acids were the predominant fat constituents. Regarding phenolic compounds, P-hydroxybenzoic and cinnamic acids were identified in the prepared methanolic and ethanolic extracts, which displayed antioxidant activity through the inhibition of thiobarbituric acid reactive substances (TBARS) formation and oxidative hemolysis; the highest activity was attributed to the R. nigricans ethanolic extract. This is the first report on the antibacterial and antibiofilm potential of the studied species, with the most promising activity observed towards Streptococcus spp. (0.20-0.78 mg/mL as the minimal inhibitory concentration, MIC). The most promising cytotoxic effect was caused by the R. integra methanolic extract on non-small cell lung cancer cells (NCI-H460). Therefore, due to the observed in vitro bioactive properties, the studied mushrooms arise as a source of functional ingredients with potential to be used in novel nutraceutical and drug formulations, which can be used in the treatment of various diseases and health conditions.

Plant Extracts and Isolated Compounds Reduce Parameters of Oxidative Stress Induced by Heavy Metals: An up-to-Date Review on Animal Studies.

BACKGROUND: Heavy metals are elements that are naturally found in the earth. They are used in many modern-day applications in agriculture, medicine, and industry. Heavy metal poisoning occurs when the body's soft tissues absorb too much of a particular metal. The heavy metals of interest for this review paper were cadmium, arsenic, mercury, and lead since these are the most common metals that the human body can absorb in toxic amounts. Different plant species were investigated in recent years for their effect on oxidative stress parameters after intoxication with heavy metals. OBJECTIVES: This review paper is focused on the current update to research on heavy metals induced oxidative stress in animal models and improvement of the oxidative stress parameters upon/co-/after treatment with different plant extracts and isolated compounds. METHODS: The available literature was screened for the novel data regarding the influence of plant extracts and compounds on heavy metals induced oxidative stress. For that purposes Scopus database was used, looking for the publications in the last 5-10 years with the key terms: plant extracts, oxidative stress, in vivo, cadmium, lead, mercury and arcenic. RESULTS: Various parameters of oxidative stress were investigated, and their improvement with plant extracts/ compounds was observed in the brain, lungs, kidneys, liver, uterus, testis, thymus, spleen, heart, skin and blood of experimental animals. Common parameters used to determine oxidative stress in animals were: superoxide dismutase; catalase; reduced glutathione; glutathione reductase; glutathione-S-transferase; glutathione peroxidase; lipid peroxidation; oxidized glutathione; malondialdehyde; xanthine oxidase; nonprotein-soluble thiol; thioredoxin reductase; total sulphydryl group; nitric oxide; γ-glutamyl cysteine synthetase. CONCLUSION: The most investigated species for antioxidant effects upon intoxication with heavy metals seem to be Allium sp., Bacopa monniera, Camellia sinensis, Moringa oleifera, Vitis vinifera and Zingiber officinale. According to literature data, the most promising effect to alleviate symptoms of intoxication was achieved with proanthocyanidins obtained from Vitis vinifera.

Actividad antimicrobiana del aceite esencial de hojas de Psidium cattleianum Afzel. ex Sabine / Antimicrobial activity of essential oil from Psidium cattleianum Afzel. ex Sabine leaves

La búsqueda de fuentes naturales para controlar los microorganismos es de interés en la producción de alimentos. Este estudio evaluó la composición química y la actividad antimicrobiana del aceite esencial de las hojas de Psidium cattleianum. El aceite esencial se extrajo por hidrodestilación y se identificó por GC-MS. La clase predominante de compuestos fueron los sesquiterpenos (47,6%) y los principales fueron trans-ß-cariofileno (14,7%), 1,8-cineol (11,7%) y É£-muuroleno (5,6%). Actividad antimicrobiana se realizó mediante la técnica de microdilución contra ocho hongos y ocho bacterias. Concentración inhibitoria mínima varió de 0,17 a 11,25 mg mL-1 para hongos y de 1,40 a 16,87 mg mL-1 para bacterias. Principales actividades fueron contra hongos Aspergillus fumigatus (ATCC 1022), Aspergillus ochraceus (ATCC 12066), Aspergillus versicolor (ATCC 11730) y Trichoderma viride (IAM 5061), y bacterias Pseudomonas aeruginosa (ATCC 27853), Bacillus cereus (clinical isolate) y Staphylococcus aureus (ATCC 6538) con potencial para prevenir enfermedades transmitidas por alimentos.

The search for natural sources to control microorganisms is of interest in food production. This study evaluated the chemical composition and antimicrobial activity of the essential oil from Psidium cattleianum leaves. The essential oil was extracted by hydrodistillation, and identified by GC-MS. The predominant class of compounds was sesquiterpenes (47.6%) and the major compounds were trans-ß-caryophyllene (14.7%), 1,8-cineole (11.7%) and É£-muurolene (5.6%). The antimicrobial activity was carried out by microdillution technique against eight fungi and eight bacteria. The minimum inhibitory concentration ranged from 0.17 to 11.25 mg mL-1 for fungi, and from 1.40 to 16.87 mg mL-1 for bacteria. The highest activities were against fungi Aspergillus fumigatus (ATCC 1022), Aspergillus ochraceus (ATCC 12066), Aspergillus versicolor (ATCC 11730), and Trichoderma viride (IAM 5061), and bacteria Pseudomonas aeruginosa (ATCC 27853), Bacillus cereus (clinical isolate), and Staphylococcus aureus (ATCC 6538) with potential to prevent foodborne diseases.

Comparative investigation on edible mushrooms Macrolepiota mastoidea, M. rhacodes and M. procera: functional foods with diverse biological activities.

This study was oriented towards the investigation of the biological properties of three wild growing and edible Macrolepiota species (M. mastoidea, M. rhacodes and Macrolepiota procera) from Serbia. The results revealed that the mushrooms have a low caloric value; free sugars such as mannitol and trehalose were identified; oxalic and malic acids were predominant organic acids, while p-hydroxybenzoic and p-coumaric acids were identified as the main phenolic compounds. Also, they were a rich source of polyunsaturated fatty acids, which dominated over monounsaturated and saturated fatty acids. Three isoforms of tocopherols were identified and quantified: α-, ß-, and δ-tocopherol. Regarding biological properties, all three species exhibited antioxidant potential, antimicrobial potential and cytotoxic activity within the different tumour cell lines tested. This study indicates that these species are indeed functional foods, due to the fact that they are edible, consumable and hold different pharmacological activities.

Biologically active compounds from two members of the Asteraceae family: Tragopogon dubius Scop. and Tussilago farfara L.

Tragopogon dubius and Tussilago farfara are consumed as vegetables and used in folk medicine to manage common diseases. Herein, the chemical compositions and biological activities of different leaf extracts (ethyl acetate, methanol, and water) of T. dubius and T. farfara were evaluated. The antibacterial, antifungal, and antioxidant abilities of the extracts were tested using different assays including free radical scavenging, reducing power, phosphomolybdenum, and metal chelating assays. Enzyme inhibitory potentials were evaluated against cholinesterases, tyrosinase, α-amylase and α-glucosidase. Complexes of bioactive compounds (chlorogenic and rosmarinic acid) were docked into the enzymatic cavity of α-glucosidase and subjected to molecular dynamic calculation, enzyme conformational stability, and flexibility analysis. T. dubius and T. farfara extracts showed remarkable antioxidant potentials. Ethyl acetate extracts of T. dubius and T. farfara were the most potent inhibitors of acetylcholinesterase and butyrylcholinesterase. T. dubius ethyl acetate extract and T. farfara methanolic extract showed noteworthy activity against α-glucosidase. High performance liquid chromatography analysis revealed the abundance of some phenolic compounds including chlorogenic and rosmarinic acids. Ethyl acetate extract of T. dubius showed notable antifungal activity against all strains. Docking studies showed best pose for chlorogenic acid was stabilized by a network of hydrogen bonds with residues Asp1157, Asp1279, whereas rosmarinic acid showed several hydrogen bonds with Asp1157, Asp1420, Asp1526, Lys1460 and Trp1369. This study further validates the use of T. dubius and T. farfara in traditional medicine, as well as act as a stimulus for further studies for future biomedicine development. Communicated by Ramaswamy H. Sarma.

Antifungal activity of Gallesia integrifolia fruit essential oil.

Gallesia integrifolia (Phytolaccaceae) is native to Brazil and has a strong alliaceous odor. The objective of this study was to identify the chemical composition of G. integrifolia fruit essential oil and evaluate fungicidal activity against the main food-borne diseases and food spoilage fungi. The essential oil was extracted by hydrodistillation and identified by GC-MS. From 35 identified compounds, 68% belonged to the organosulfur class. The major compounds were dimethyl trisulfide (15.49%), 2,8-dithianonane (52.63%) and lenthionine (14.69%). The utilized fungi were Aspergillus fumigatus, Aspergillus niger, Aspergillus ochraceus, Aspergillus versicolor, Penicillium funiculosum, Penicillium ochrochloron, Penicillium verrucosum var. cyclopium, and Trichoderma viride. Minimal fungicidal concentration for the essential oil varied from 0.02 to 0.18mg/mL and bifonazole and ketoconazole controls ranged from 0.20 to 3.50mg/mL. The lower concentration of the essential oil was able to control P. ochrochloron, A. fumigatus, A. versicolor, A. ochraceus and T. viride. This study shows a high fungicidal activity of G. integrifolia fruit essential oil and can support future applications by reducing the use of synthetic fungicides.

Identification of phenolic components via LC-MS analysis and biological activities of two Centaurea species: C. drabifolia subsp. drabifolia and C. lycopifolia.

The Centaurea genus has great potential in traditional systems and has attracted much interest in the design of novel drug formulations. The present study was focused on the chemical fingerprints and biological properties of Centaurea drabifolia subsp. drabifolia and Centaurea lycopifolia extracts. Spectrophotometric and LC-MS techniques were used to establish the chemical profiles of the studied extracts. Enzyme inhibitory potential was assessed against key enzymes linked to global health problems, namely neurodegenerative diseases (acetylcholinesterase), pigmentation (tyrosinase), and diabetes (α-amylase and α-glucosidase). The antimicrobial propensities of the extract were evaluated against 16 bacterial and fungal strains using the microdilution method. The antioxidant abilities were assessed using DPPH and ABTS radical scavenging, ferric, and cupric reducing powers, phosphomolybdenum, and ferrous metal chelation. The total phenolic compounds varied from 18.33 to 32.84mgGAE/g extract. Total flavonoid content of the extracts were in the range of 2.88-22.39mgRE/g extract. Methanol and water extracts showed stronger antioxidant abilities compared to the ethyl acetate extracts. However, the latter extracts were most efficient towards the target enzymes (except for tyrosinase). The water extracts also exerted considerable antimicrobial effects. Findings from the present work tend to support the idea that C. drabifolia subsp. drabifolia and C. lycopifolia may be utilized as effective bio-resources for designing novel health-promoting products or ingredients. It is anticipated that results amassed from this still will open new avenues for research and contribute towards establishing primary data on these species for designing novel phytopharmaceuticals.

Chemical, nutritive composition and a wide range of bioactive properties of honey mushroom Armillaria mellea (Vahl: Fr.) Kummer.

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.

Shedding light on the biological and chemical fingerprints of three Achillea species (A. biebersteinii, A. millefolium and A. teretifolia).

Representatives of the Achillea genus are widely used as foods or nutraceuticals. Considering the increasing demand for herbal dietary supplements with health promoting effects, the objective of this research was to evaluate the biological and chemical profiles of different extracts (ethyl acetate, methanol and water) obtained from three Achillea species (A. biebersteinii, A. millefolium and A. teretifolia). The antioxidant (free radical scavenging (DPPH and ABTS), reducing power (CUPRAC and FRAP), metal chelating and phosphomolybdenum), enzyme inhibitory (anti-cholinesterase, anti-tyrosinase, anti-amylase and anti-glucosidase) and antimicrobial (antibacterial and antifungal) effects were assessed to investigate their biological profiles. Moreover, the total phenolic and flavonoid contents were determined and LC-MS analysis was performed for the chemical profile of the investigated extracts. The LC-MS analysis revealed the presence of several caffeoylquinic acids in these extracts. Generally, the methanol and water extracts exhibited stronger antioxidant abilities, which correlated with the higher levels of phenolic compounds when compared to the ethyl acetate extracts. In addition, the best antimicrobial activities were obtained for the ethyl acetate and methanolic extracts. However, the ethyl acetate extract had remarkable enzyme inhibitory potential. On the basis of our results, Achillea species may be promoted as promising sources of natural agents and used for the development of nutraceuticals or functional food ingredients.

Biological Activities of Sesquiterpene Lactones Isolated from the Genus Centaurea L. (Asteraceae).

BACKGROUND: In recent years, a growing interest has developed in the field of biological activity of plant metabolites. Research in this area considering antimicrobial, antioxidant, cytotoxic, anti-inflammatory, and other properties, is currently expanding, reporting various species to possess such biological effects. Among them, Centaurea species are well known to be used in ethnomedicine. The Centaurea genus (Asteraceae) is represented by more than 500 species, mostly located in the Mediterranean region and Western Asia. METHODS: The current revision focuses on up-to-date literature on the isolation, structural elucidation and biological properties of sesquiterepene lactones from Centaurea species, regarding antimicrobial, antitumour, antiviral, anti-inflammatory and cytotoxic properties. The methods for extraction, isolation and identification are also pointed out and the bioactivity of lactones as purified compounds discussed. Several general ideas about the structural requirements for activity, based on the in vitro bioassays and the in silico prediction of their ADME properties are discussed. RESULTS: Investigations of chemical analyses and biological potential exhibited that flavonoids and sesquiterpene lactones, in particular germacranolides, eudesmanolides, elemanolides, and guaianolides, are compounds responsible for the biological potential of plants. Sesquiterpene lactones represent a group of compounds responsible for the medicinal characteristics of Centaurea species. DISCUSSION: Investigation of structure-activity relationships of all data helps the understanding of the bioactivity resulting from chemical aspects. All activities are discussed profoundly, paying special attention to molecular mechanisms involved in the implication of the health-beneficial effects of these compounds and in order to point them out as candidates for new drug discovery, and as safe natural agents.

Lignin model compound in alginate hydrogel: a strong antimicrobial agent with high potential in wound treatment.

Nowadays bacterial resistance to known antibiotics is a serious health problem. In order to achieve more efficient treatment, lately there is an effort to find new substances, such as certain biomaterials, that are non-toxic to humans with antibiotic potential. Lignins and lignin-derived compounds have been proposed to be good candidates for use in medicine and health maintenance. In this study, the antibacterial activity of the lignin model polymer dehydrogenate polymer (DHP) in alginate hydrogel (Alg) was studied. The obtained results show that DHP-Alg has strong antimicrobial activity against several bacterial strains and biofilms and does not have a toxic effect on human epithelial cells. These results strongly suggest its application as a wound healing agent or as an adjunct substance for wound treatments.

Phenolic compounds and biological effects of edible Rumex scutatus and Pseudosempervivum sempervivum: potential sources of natural agents with health benefits.

The present study outlines a chemical characterization and further effects beneficial to health of edible Rumex scutatus and Pseudosempervivum sempervivum, in addition to presenting the antioxidant, enzyme inhibitory effects and antimicrobial properties of different extracts. The phenolic compounds composition of the extracts was assessed by RP-HPLC-DAD, outlining benzoic acid and rutin as major constituents in P. sempervivum and rutin and hesperidin in R. scutatus. Moreover, further biological effects were tested on key enzymes involved in diabetes mellitus, Alzheimer's disease and skin melanogenesis revealing an important tyrosinase inhibitory effect of Pseudosempervivum water extract. Moreover, both species possessed antimicrobial properties towards bacteria and fungi relevant to public health. Accordingly, we find that R. scutatus and P. sempervivum can be considered as novel functional foods because they are rich sources of biologically active compounds that provide health benefits.

In vitro antibiofilm activity of the freshwater bryozoan Hyalinella punctata: a case study of Pseudomonas aeruginosa PAO1.

The antibiofilm and possible antiquorum sensing effects against the strain Pseudomonas aeruginosa PAO1 of five crude extracts of the freshwater bryozoan Hyalinella punctata (Hancock, 1850) were evaluated in vitro for the first time. H. punctata ethyl acetate extract (HpEtAc) exhibited the highest antibiofilm activity reducing the biofilm formation of P. aeruginosa PAO1 in the range of 80.63-88.13%. While all tested extracts reduced the twitching motility of the aforementioned bacterial strain, HpEtAc showed to be the most effective. Finally, at a concentration of 0.5 MIC, the same extract mostly inhibited the production of pyocyanin by P. aeruginosa PAO1 (71.53%). In comparison both with the positive controls used (streptomycin and ampicillin, 67.13 and 69.77%, respectively), HpEtAc was found to inhibit pyocyanin in a higher extent. An extensive chemical characterisation of this particular extract may result in isolation and identification of novel lead compounds targeting P. aeruginosa, an opportunistic human pathogen.

Correction: Rosa canina L.--new possibilities for an old medicinal herb.

Correction for 'Rosa canina L. - new possibilities for an old medicinal herb' by Jelena Zivkovic et al., Food Funct., 2015, DOI: 10.1039/c5fo00820d.

Ethnopharmacological uses of Sempervivum tectorum L. in southern Serbia: Scientific confirmation for the use against otitis linked bacteria.

ETHNOPHARMACOLOGICAL RELEVANCE: Sempervivum tectorum L. (Crassulaceae), known as houseleek, is used in traditional medicine in the treatment of ear inflammation. It can be spread as a pack on wounds, sores, burns, and abscesses and also on painful areas attacked by gout as a refrigerant and astringent. Drinking tea prepared from leaves of S. tectorum is recommended for ulcer treatment. The present study was designed to investigate ethopharmacological use of S. tectorum in the southern Serbia and to further scientifically justify and confirm effectiveness of the leaf juice used in ethnomedicine for ear inflammation, against otitis linked bacteria. MATERIAL AND METHODS: Ethnopharmacological survey on the use of S. tectorum in southern Serbia was performed using semi structured questionnaires via a face-to-face interview. Chemical composition of the leaf juice regarding phenolic compounds and organic acids was analyzed. Antimicrobial activity was tested on bacteria isolated from ear swabs of the patients suffering from the ear pain (otitis). Anti-quorum-sensing activities of the juice were further investigated on Pseudomonas aeruginosa. RESULTS: Ethnopharmacological survey revealed the use of S. tectorum in southern Serbia for the treatment of ear pain, warts, cancer, stomachache, ulcer and high blood sugar level with the highest fidelity level (FL) for the ear pain. The phenolic composition of the S. tectorum leaf juice consisted of flavonol glycosides, with kaempferol-3-O-rhamnosyl-glucoside-7-O-rhamnoside as the majority compound. Organic acids composition revealed malic acid as the most dominant one. Antimicrobial and anti-quorum-sensing activities of the juice showed to be promising. CONCLUSION: Ethnopharmacological use of S. tectorum juice for treating ear pain is justified, since the juice possessed antimicrobial activity towards clinical isolates of bacteria linked to otitis.

Rosa canina L.--new possibilities for an old medicinal herb.

Health beneficial properties of Rosa canina species are mainly attributed to rose hips, while the leaves are usually discarded as waste. In the present study we investigated chemical constituents as well as antimicrobial and antibiofilm potential of R. canina methanolic leaf extract. Chemical analysis showed that dominant phenolic compounds are quercetin and isorhamnetin derivatives (isoquercetin and isorhamnetin-3-O-rutinoside). Among the tested bacteria, Pseudomonas aeruginosa and Salmonella typhimurium were the most susceptible to the activity of R. canina leaf extract with MIC and MBC values both 0.009 mg mL(-1). For most of the bacterial strains investigated the extract showed significantly higher activity compared to the used standard compounds streptomycin and ampicillin. Also the tested extract powerfully inhibited in vitro biofilm growth in Pseudomonas aeruginosa, Staphylococcus aureus, Leishmania monocytogenes and Escherichia coli at sub MIC-levels. With concentrations equal to 1/4 and 1/8 of MIC values biofilm growth of P. aeruginosa and E. coli was inhibited by 90%. The obtained results are significant for a wider and efficient use of R. canina leaves.