Multidirectional Characterization of Phytochemical Profile and Health-Promoting Effects of Ziziphora bungeana Juz. Extracts.

Ziziphora species (Lamiaceae) have been used in traditional medicine as sedatives, antiseptics, carminatives, or expectorants. Despite their common applications in phytotherapy, there is still lack of evidence about the composition of their extracts and its impact on biological properties of the plants. The aim of this study was to evaluate the content of Ziziphora bungeana, a less studied species growing in Kazakhstan, using HPLC-ESI-QTOF-MS/MS instrumentation and to determine its antimicrobial, antioxidant, and cytotoxic activity together with inhibitory properties against tyrosinase and toxicity in erythrocyte lysis assay. Extracts from Z. bungeana were found to be sources of flavonoids, phenolic acids, organic acids, and terpenes that determined their antiradical activity. The minimum inhibitory concentrations of extracts were lower for Gram-positive bacteria (1.25-10 mg/mL) than for Gram-negative bacteria and fungi (5-20 mg/mL). The EC50 value calculated for antiradical activity ranged between 15.00 ± 1.06 µg/mL and 13.21 ± 3.24 µg/mL for ABTS and DPPH assays, respectively. Z. bungeana extracts were found to decrease the activity of tyrosinase by 50% (at 200 µg/mL) similarly to kojic acid and were slightly cytotoxic for human melanoma A375 cell line (at 200 µg/mL) with no effect on HaCaT keratinocytes. In the end, Z. bungeana did not reveal toxic effects in hemolytic assay as compared to the positive control Triton X-100. The performed tests show potential application of the plant in the treatment of infectious diseases, disorders caused by free radicals, and skin problems.

Phytochemical Profile and Biological Activity of the Ethanolic Extract from the Aerial Part of Crocus alatavicus Regel & Semen Growing Wildly in Southern Kazakhstan.

The composition of the ethanolic extract from the aerial parts of Crocus alatavicus Regel & Semen from southern Kazakhstan spontaneous flora was analyzed together with the determination of its antibacterial, antifungal, antiviral and anticancer activity. The phytochemical profile analysis by high-performance liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (HPLC/ESI-QTOF-MS) revealed the presence of multiple kaempferol derivatives. High-performance reverse-phase liquid chromatography combined with a photodiode-array detection (RP-HPLC/PDA) found that kaempferol 3-O-dihexoside and kaempferol 3-O-acyltetrahexoside accounted for 70.5% of the kaempferol derivatives. The minimum inhibitory concentration (MIC) values of the extract for all the tested reference microorganisms were high, reaching 10 mg/mL for yeasts and 20 mg/mL for bacteria. In contrast, antiviral activity was observed at 2 mg/mL, resulting in the inhibition of the HSV-1-induced cytopathic effect and the reduction in virus infectious titer by 1.96 log, as well as the viral load by 0.85 log. Among the tested prostate cancer cell lines, significant cytotoxic activity of the extract was noted only on the LNCaP cell line, with an IC50 value of 1.95 mg/mL. The LNCaP cell line treated with 2 mg/mL of the extract showed a noticeably reduced number of spindle-shaped cells with longer cellular projections, a significant increase in the peak corresponding to the population of apoptotic cells in the sub-G1 phase and a decreased intracellular glutathione (GSH) level, suggesting the prooxidative properties of the extract. The obtained data provide novel information about the flavonoids present in the aerial part of C. alatavicus and suggest its potential application as a source of the compounds active against HSV-1 and metastatic, androgen-sensitive prostate cancer.

Yarrowia lipolytica as an Alternative and Valuable Source of Nutritional and Bioactive Compounds for Humans.

Yarrowia lipolytica, an oleagineous species of yeast, is a carrier of various important nutrients. The biomass of this yeast is an extensive source of protein, exogenous amino acids, bioavailable essenctial trace minerals, and lipid compounds as mainly unsaturated fatty acids. The biomass also contains B vitamins, including vitamin B12, and many other bioactive components. Therefore, Y. lipolytica biomass can be used in food supplements for humans as safe and nutritional additives for maintaining the homeostasis of the organism, including for vegans and vegetarians, athletes, people after recovery, and people at risk of B vitamin deficiencies.

The Antimicrobial Properties of Poplar and Aspen-Poplar Propolises and Their Active Components against Selected Microorganisms, including Helicobacter pylori.

There is a noticeable interest in alternative therapies where the outcome is the eradication of the Gram-negative bacterium, Helicobacter pylori (H. pylori), for the purpose of treating many stomach diseases (chronic gastritis and peptic ulcers) and preventing stomach cancer. It is especially urgent because the mentioned pathogen infects over 50% of the world's population. Recent studies have shown the potential of natural products, such as medicinal plant and bee products, on the inhibition of H. pylori growth. Propolis is such a bee product, with known antimicrobial activities. The main scope of the study is the determination of the antimicrobial activity of ethanolic extracts from 11 propolis samples (mostly from Poland, Ukraine, Kazakhstan, and Greece) against H. pylori, as well as selected bacterial and yeast species. The most effective against H. pylori was the propolis from Ukraine, with an MIC = 0.02 mg/mL while the rest of samples (except one) had an MIC = 0.03 mg/mL. Moreover, significant antimicrobial activity against Gram+ bacteria (with an MIC of 0.02-2.50 mg/mL) and three yeasts (with an MIC of 0.04-0.63 mg/mL) was also observed. A phytochemical analysis (polyphenolic profile) of the propolis samples, by ultra-high-performance liquid chromatography-diode array detector-mass spectrometry (UPLC-DAD-MS), was performed. An evaluation of the impact of the propolis components on antimicrobial activity, consisting of statistical analyses (principal component analysis (PCA) and hierarchical fuzzy clustering), was then performed. It was observed that the chemical composition characteristics of the poplar propolis correlated with higher antibacterial activity, while that of the poplar and aspen propolis correlated with weaker antibacterial activity. To summarize the activity in vitro, all tested propolis samples indicate that they can be regarded as useful and potent factors in antimicrobial therapies, especially against H. pylori.

Clove Essential Oil and Its Main Constituent, Eugenol, as Potential Natural Antifungals against Candida spp. Alone or in Combination with Other Antimycotics Due to Synergistic Interactions.

The occurrence of candidiasis, including superficial infections, has recently increased dramatically, especially in immunocompromised patients. Their treatment is often ineffective due to the resistance of yeasts to antimycotics. Therefore, there is a need to search for new antifungals. The aim of this study was to determine the antifungal effect of clove essential oil (CEO) and eugenol (EUG) towards both reference and clinical Candida spp. strains isolated from the oral cavity of patients with hematological malignancies, and to investigate their mode of action and the interactions in combination with the selected antimycotics. These studies were performed using the broth microdilution method, tests with sorbitol and ergosterol, and a checkerboard technique, respectively. The CEO and EUG showed activity against all Candida strains with a minimal inhibitory concentration (MIC) in the range of 0.25-2 mg/mL. It was also found that both natural products bind to ergosterol in the yeast cell membrane. Moreover, the interactions between CEO and EUG with several antimycotics-cetylpyridinium chloride, chlorhexidine, silver nitrate and triclosan-showed synergistic or additive effects in combination, except nystatin. This study confirms that the studied compounds appear to be a very promising group of phytopharmaceuticals used topically in the treatment of superficial candidiasis. However, this requires further studies in vivo.

The Phenolic Compounds Profile and Cosmeceutical Significance of Two Kazakh Species of Onions: Alliumgalanthum and A. turkestanicum.

Numerous species of Allium genus have been used in the traditional medicine based on their vast biological effects, e.g., antimicrobial, digestion stimulant, anti-sclerotic, soothing, antiradical or wound healing properties. In this work, unpolar and polar extracts from two lesser-investigated species of Allium growing in Kazakhstan, Alliumgalanthum Kar. & Kir. (AG) and A. turkestanicum Regel. (AT), were studied for their composition and biological effects. In the HPLC-ESI-QTOF-MS/MS analyses of water and alcoholic extracts simple organic acids, flavonoids and their glycosides were found to be the best represented group of secondary metabolites. On the other hand, in the GC-MS analysis diethyl ether, extracts were found to be rich sources of straight-chain hydrocarbons and their alcohols, fatty acids and sterols. The antimicrobial activity assessment showed a lower activity of polar extracts, however, the diethyl ether extract from AT bulbs and AG chives showed the strongest activity against Bacillus subtilis ATCC 6633, B. cereus ATCC 10876, some species of Staphylococcus (S. aureus ATCC 25923 and S. epidermidis ATCC 12228) and all tested Candida species (Candida albicans ATCC 2091, Candida albicans ATCC 10231, Candida glabrata ATCC 90030, Candida krusei ATCC 14243 and Candida parapsilosis ATCC 22019) with a minimum inhibitory concentration of 0.125-0.5 mg/mL. The highest antiradical capacity exhibited diethyl ether extracts from AG bulbs (IC50 = 19274.78 ± 92.11 mg Trolox eq/g of dried extract) in DPPH assay. In ABTS scavenging assay, the highest value of mg Trolox equivalents, 50.85 ± 2.90 was calculated for diethyl ether extract from AT bulbs. The same extract showed the highest inhibition of mushroom tyrosinase (82.65 ± 1.28% of enzyme activity), whereas AG bulb ether extract was the most efficient murine tyrosinase inhibitor (54% of the enzyme activity). The performed tests confirm possible cosmeceutical applications of these plants.

Phytochemical Fingerprinting and In Vitro Antimicrobial and Antioxidant Activity of the Aerial Parts of Thymus marschallianus Willd. and Thymus seravschanicus Klokov Growing Widely in Southern Kazakhstan.

The chemical composition of the hydroethanolic extracts (60% v/v) from the aerial parts of Thymus marschallianus Willd (TM) and Thymus seravschanicus Klokov (TS) from Southern Kazakhstan flora was analyzed together with their hexane fractions. Determination of antibacterial, antifungal and antioxidant activities of both extracts was also performed. RP-HPLC/PDA and HPLC/ESI-QTOF-MS showed that there were some differences between the composition of both extracts. The most characteristic components of TM were rosmarinic acid, protocatechuic acid, luteolin 7-O-glucoside, and apigenin 7-O-glucuronide, while protocatechuic acid, luteolin 7-O-glucoside, luteolin 7-O-glucuronide, and eriodictyol predominated in TS. The content of polyplenols was higher in TS than in TM. The GC-MS analysis of the volatile fraction of both examined extracts revealed the presence of thymol and carvacrol. Additionally, sesquiterpenoids, fatty acids, and their ethyl esters were found in TM, and fatty acid methyl esters in TS. The antioxidant activity of both extracts was similar. The antibacterial activity of TS extract was somewhat higher than TM, while antifungal activity was the same. TS extract was the most active against Helicobacter pylori ATCC 43504 with MIC (minimal inhibitory concentration) = 0.625 mg/mL, exerting a bactericidal effect. The obtained data provide novel information about the phytochemistry of both thyme species and suggest new potential application of TS as a source of bioactive compounds, especially with anti-H. pylori activity.

Production of enriched in B vitamins biomass of Yarrowia lipolytica grown in biofuel waste.

Yarrowia lipolytica as an oleaginous yeast is capable of growing in various non-conventional hydrophobic substrate types, especially industrial wastes. In this study, the content of thiamine (vitamin B1), riboflavin (vitamin B2), pyridoxine (vitamin B6), biotin (vitamin B7) and folic acid (vitamin B9) in the wet biomass of Y. lipolytica strains cultivated in biofuel waste (SK medium), compared to the standard laboratory YPD medium, was assessed. Additionally, the biomass of Y. lipolytica A-101 grown in biofuel waste (SK medium) was dried and examined for B vitamins concentration according to the recommended microbial methods by AOAC Official Methods. The mean values of these vitamins per 100 g of dry weight of Y. lipolytica grown in biofuel waste (SK medium) were as follows: thiamine 1.3 mg/100 g, riboflavin 5.3 mg/100 g, pyridoxine 4.9 mg/100 g, biotin 20.0 µg/100 g, and folic acid 249 µg/100 g. We have demonstrated that the dried biomass is a good source of B vitamins which can be used as nutraceuticals to supplement human diet, especially for people at risk of B vitamin deficiencies in developed countries. Moreover, the biodegradation of biofuel waste by Y. lipolytica is desired for environmental protection.

The In Vitro Activity of Essential Oils against Helicobacter Pylori Growth and Urease Activity.

The anti-H. pylori properties of 26 different commercial essential oils were examined in vitro by MIC (minimal inhibitory concentration) determination for the reference strain H. pylori ATCC 43504. We selected 9 essential oils with different anti-Helicobacter activities and established their phytochemical composition and urease inhibition activities. Phytochemical analysis of the selected essential oils by GC-MS method and antioxidant activity were performed. The phenol red method was used to screen the effect of essential oils on urease activity expressed as IC50 (the half of maximal inhibitory concentration). The most active essential oils, with MIC = 15.6 mg/L, were thyme, lemongrass, cedarwood and lemon balm oils; MIC = 31.3 mg/L-oregano oil; MIC = 62.5 mg/L-tea tree oil; MIC = 125 mg/L-pine needle, lemon and silver fir oils with bactericidal effect. Urease activity was inhibited by these oils with IC50 ranged from 5.3 to > 1049.9 mg/L. The most active was cedarwood oil (IC50 = 5.3 mg/L), inhibiting urease at sub-MIC concentrations (MIC = 15.6 mg/L). The statistical principal component analysis allowed for the division of the oils into three phytochemical groups differing in their anti-H. pylori activity. To summarize, the activity in vitro of the five essential oils silver fir, pine needle, tea tree, lemongrass, and cedarwood oils against H. pylori was found in this paper for the first time. The most active against clinical strains of H. pylori were cedar wood and oregano oils. Moreover, cedarwood oil inhibited the urease activity at subinhibitory concentrations. This essential oil can be regarded as a useful component of the plant preparations supporting the eradication H. pylori therapy.

Phytochemical composition of wormwood (Artemisia gmelinii) extracts in respect of their antimicrobial activity.

BACKGROUND: Extracts from medicinal plants with phytochemicals with known antimicrobial properties can be an effective adjunct in the complex treatment of infectious diseases. This study aimed to evaluate the antimicrobial activity of wormwood extracts collected in Kazakhstan (Artemisia gmelinii Weber ex Stechm.), along with their phytochemical analysis. METHODS: The ethanolic and chloroform extracts were subjected to HPLC combined with quadrupole time-of-flight mass spectrometry method. For quantitative assessment of antimicrobial activity, minimal inhibitory concentration (MIC) of the tested extracts was determined by micro-dilution broth method for the panel of the reference microorganisms. Minimal bactericidal concentration (MBC) or minimal fungicidal concentration (MFC) were also determined. RESULTS: LC/MS analysis showed the presence of 13 compounds in the tested extracts, including flavonoids: apigenin, luteolin, rutin, two O-methylated flavonols (isorhamnetin, rhamnazine), coumarin compounds (umbelliferone, scopoletin and scopolin (scopoletin 7-glucoside), 3-hydroxycoumarin and 4-hydroxycoumarin), chlorogenic acid and two dicaffeoylquinic acid isomers. Quantitative HPLC analysis showed that umbelliferone was dominant in the chloroform extract while chlorogenic acid was identified as a main compound in the ethanolic extract. The antibacterial and antifungal activity of chloroform and ethanolic extracts was comparable. The most sensitive were the Gram-positive bacteria represented by staphylococci, Micrococcus luteus and Bacillus spp. (MIC = 1.25-5 mg/ml) and yeasts represented by Candida spp. (MIC = 2.5-5 mg/ml), irrespective of the assayed extract. CONCLUSIONS: Extracts of wormwood Artemisia gmelinii have shown a wide spectrum of antibacterial and antifungal activity. Luteolin, rutin, isorhamnetin and scopolin were identified in A. gmelinii species for the first time. The determining of the most potential compounds of Artemisia gmelinii can be used to develop effective antibacterial and antifungal agents.

Antimicrobial Potential of Single Metabolites of Curcuma longa Assessed in the Total Extract by Thin-Layer Chromatography-Based Bioautography and Image Analysis.

Curcuma longa from Zingiberaceae belongs to the major spices consumed around the world, known from its cholagogue, anti-inflammatory, and antimicrobial properties. Lack of data on the activity of single components of turmeric extract encouraged the authors to apply TLC (thin-layer chromatography) based bioautography studies to reveal its antimicrobial constituents and construct a universal platform for the bioactivity assessment of crude extracts, with help of a freeware ImageJ software. This optimized chromatographic bioassay performed on diethyl ether and methanol extracts of Curcuma longa was successfully applied on the total extract and revealed the antimicrobial potential of single components against a variety of Gram-positive strains, with no need for their isolation from the mixture. The obtained results were further confronted with a classic microdilution antimicrobial assay on the isolates, purified from the crude extracts by centrifugal partition chromatography in the following solvent system: heptane-chloroform-methanol-water (5:6:3:2) (v/v/v/v).

Liquid chromatographic techniques in betacyanin isomers separation from Gomphrena globosa L. flowers for the determination of their antimicrobial activities.

High-speed counter-current chromatography (HSCCC) combined with HPLC were established to purify, for the first time, betacyanin isomers from Gomphrena globosa L. flowers. The mixture of tert-butyl methyl ether - butanol - methanol - water TBME-BuOH-MeOH-H2O (1.0% heptafluorobutyric acid HFBA) 2:2:1:5 (v/v/v/v) in reversed phase mode was used for preliminary purification of gomphrenin derivatives. Then, semiprep-HPLC was used to obtained ten pure betacyanins: gomphrenins II and III with their cis-isomers as well as sinapoyl-gomphrenin I and its corresponding diastereomers. This is the first study on separation of naturally coexisting acylated gomphrenin isomers. The isolated compounds showed a broad antimicrobial spectrum (in the range of 0.19-1.5 mg mL-1) by inhibiting the growth of all of food-borne pathogens tested. The antimicrobial activity of acylated betacyanins was higher than that of non-acylated gomphrenin I/isogomphrenin I. Therefore, the acylation with phenolic acids increases the activity of betacyanins against fungi and bacteria, suggesting a synergetic effect of the acylated moieties and the pigment chromophoric system on the activity, which was evaluated for the first time.

Metabolic Profile of and Antimicrobial Activity in the Aerial Part of Leonurus turkestanicus V.I. Krecz. et Kuprian. from Kazakhstan.

An HPLC quadrupole time-of-flight (Q-TOF) MS method was developed for the identification of secondary metabolites in Leonurus turkestanicus V.I. Krecz. et Kuprian. Ethanolic and chloroform extracts from the plant's aerial parts were tested. A total of 16 compounds (iridoid glycosides, phenylpropanoids, flavonoids, and nitrogen-containing compounds, as well as diterpene acetate derivatives) were identified and tentatively characterized based on (or using) their retention times and UV and Q-TOF-MS data. Previously reported aucubin (1), 6-deoxy-8-acetylharpagid (2), and stachydrine (13, 15) and homostachydrine isomers (14, 16) were identified, along with a lavandulifolioside isomer (3), verbascoside (4), rutin (5), 3-O-kaempferol rutinoside (6), and an unknown diterpene acetate (8). Compounds 3-6 were detected for the first time in this plant. Additionally. antimicrobial activity was evaluated. No significant differences were found between ethanolic and chloroform extracts of L. turkestanicus; however, the alcoholic extract showed stronger antifungal activity [minimal inhibitory concentration (MIC) of 2.5-5 mg/mL], whereas the chloroform extract showed stronger activity against the tested spore-forming Bacillus species (MIC 1.25-2.5 mg/mL).

Biological activity and safety profile of the essential oil from fruits of Heracleum mantegazzianum Sommier & Levier (Apiaceae).

A composition of essential oils obtained from Heracleum mantegazzianum (Apiaceae) was examined using a GC-MS method. n-Octyl acetate (19.92%), n-hexyl-2-methylbutanoate (10.84%), n-octanol (10.13%), n-octyl butanoate (8.88%), n-octyl-2-methylbutanoate (8.01%), n-hexyl acetate (7.11%), n-octyl isobutanoate (5.5%) and n-hexyl isobutanoate (5.43%) were the main compounds. The high-performance counter-current chromatography was applied for purification of aliphatic alcohols and esters. A mixture of n-hexane, acetonitrile and tetr-butyl methyl ether (1:1:0.1, v/v) allowed to obtain n-octanol, n-octyl acetate, n-hexyl-2- methylbutanoate, n-octyl isobutanoate and n-octyl-2-methylbutanoate, with the purity range of 94-99%, in one single 74 min run. The antimicrobial activity was also determined against plant and foodborne pathogens. While n-octanol shares responsibility for the antibacterial activity of the essential oil, n-octyl acetate determines its antifungal action. The cytotoxic activity assessed on two normal kidney fibroblast cell lines: Vero (animal) and HEK-293 (human embryonic), and two human cancer cell lines: FaDu (squamous cell carcinoma of the pharynx) and SCC25 (squamous cell carcinoma of the tongue), showed a moderate cytotoxicity with CC50 values ranging from 262.3 to 567.8 µg/mL. Results indicate that normal cell lines were more sensitive to the tested essential oil than cancer cell lines. The antioxidant activity of oil and pure compounds was not significant.

Multidirectional characterisation of chemical composition and health-promoting potential of Rosa rugosa hips.

Rugosa rose provides one of the largest hips frequently used in the preparation of pharmaceutical and food products. The aim of work was to conduct multidirectional study of biological activity and chemical composition of Rosa rugosa hips. Antiradical, cytotoxic (against cervical and breast cancer cell lines), antibacterial (against eight bacterial strains) and antifungal potential of the species in question was evaluated. Total contents of phenolics, phenolic acids, flavonoids, tannins, carotenoids and ascorbic acid were determined. LC-ESI-MS/MS analysis was performed in order to investigate closely phenolic acids and flavonoid glycosides. As a result, interesting selective cytotoxic effects on cervical (HeLa) and breast cancer (T47D) cell lines, significant antiradical activity (EC50 2.45 mg mg-1 DPPH•) and moderate antimicrobial potential (MIC 0.625-1.25 mg mL-1) were observed. Nine phenolic acids and 11 flavonoid glycosides were qualitatively and quantitatively determined, including 7 compounds previously not reported in R. rugosa hips.

ANALYSIS OF PHENOLIC ACIDS AND ANTIBACTERIAL ACTIVITY OF EXTRACTS OBTAINED FROM THE FLOWERING HERBS OF CARD UUS ACANTHOIDES L.

In this work the phenolic acids in crude methanol extracts from the flowering herbs of Carluus acanthoides L. were identified. The samples containing free phenolic acids and those released after acid and alka- line hydrolyses were investigated by 2D TLC on cellulose. After purification by SPE, samples were also analyzed by RP-HPLC. Chlorogenic, protocatechuic, p- coumaric, caffeic, syringic, p-hydroxybenzoic, ferulic, vanillic, gentisic and gallic acids were detected in fractions of the methanolic extract obtained from the flow- ering herb of C. acanthoides. This is the first study concerning the qualitative analysis of phenolic compounds and antibacterial activity of fractions and aqueous, ethyl acetate, dichloromethane, acetone and methanol (50, 80 and 100% v/v) extracts of flowering herbs of C. acanthoides L. The antimicrobial activity of tested extracts was determined in vito against reference microorganisms of Gram-positive bacteria, Gram-negative bacteria and fungi belonging to yeasts. The results of this study support the medical usage of C. acanthoides L. due to its antimicrobial properties.

Haemophilus parainfluenzae as a marker of the upper respiratory tract microbiota changes under the influence of preoperative prophylaxis with or without postoperative treatment in patients with lung cancer.

BACKGROUND: Haemophili are representative microbiota of the upper respiratory tract. The aim of this study was to assess the effects of perioperative antimicrobial prophylaxis and/or postoperative treatment on Haemophilus parainfluenzae prevalence, and antimicrobial sensitivity in short-term hospitalized patients with lung cancer who underwent surgery. RESULTS: Samples were collected from 30 short-term hospitalized patients with lung cancer and from 65 healthy people. The nasal and throat specimens were taken twice from each patient: before (EI, Examination I), on the fourth/fifth day (EII, Examination II) after surgery, and once from healthy people. The isolates identification and antimicrobial susceptibility were detected by routine diagnostic methods. H. parainfluenzae was found in throat specimens of 42/65 (64.6 %) healthy people, while in 19/30 (63.3 %) lung cancer patients in EI (p = 0.6203) and in 13/30 (43.3 %) ones in EII (p = 0.0106). Neither the disease itself nor short-term hospitalization with perioperative prophylaxis alone affected H. parainfluenzae prevalence in EII, while perioperative prophylaxis with postoperative treatment significantly decreased its colonization in EII. The differences in the number of patients colonized by Candida spp. in EI and in EII were observed (p = 0.0082).Totally, 23/58 (39.7 %) of H. parainfluenzae isolates were resistant mainly to beta-lactams; among 11 ampicillin-resistant isolates only 3 were beta-lactamase positive. CONCLUSIONS: The antimicrobial perioperative prophylaxis together with postoperative treatment may disturb the composition of the airways microbiota represented by H. parainfluenzae, in addition to selecting the resistant strains of bacteria and promoting yeasts colonization in lung cancer patients undergoing surgery.

Bioactivity-guided isolation of antimicrobial coumarins from Heracleum mantegazzianum Sommier & Levier (Apiaceae) fruits by high-performance counter-current chromatography.

An efficient strategy, based on bioassay-guided fractionation, high-performance liquid chromatography (HPLC), and high-performance counter-current chromatography (HPCCC), was established to purify and evaluate the bioactive compounds from the dichloromethane extract of the fruits of Heracleum mantegazzianum Sommier & Levier (Apiaceae). The quaternary solvent system n-heptane-ethyl acetate-methanol-water (6:5:6:5 v/v) was used in the reversed phase mode. Using this method, in a single run, seven fractions were isolated, among them three were the pure furanocoumarins: pimpinellin, imperatorin, and phellopterin. In order to purify xanthotoxin a more polar system (1:1:1:1 v/v) was further applied. The antimicrobial activity of extract, chromatographic fractions, and single compounds were in the range of MIC = 0.03-1 mg mL(-1). Xanthotoxin may have priority as a compound of further interest based on its antimicrobial activity. For the first time, an extensive antimicrobial study was performed for pimpinellin and phellopterin.

Chemical compositions and antibacterial activity of extracts obtained from the inflorescences of Cirsium canum (L.) all.

The aim of this study was to investigate phenolic acids and flavonoids in methanolic, dichloromethane, acetone and ethyl acetate extracts and fractions from inflorescences of Cirsium canum (L.). RP-HPLC analysis enabled identification of the following: chlorogenic acid, caffeic acid, p-coumaric acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, syringic acid, trans-cinnamic acid, luteolin-7-glucoside, apigenin-7-glucoside, kaempferol-3-glucoside, linarin, apigenin, rutoside, luteolin and kaempferol. The antimicrobial activity of tested extracts was determined in vitro against reference microorganisms, including bacteria or fungi, belonging to yeasts. Our data showed that the tested extracts had no influence on the growth of the reference strains of Gram-negative bacteria and yeasts belonging to Candida spp. Among them, the fractions possessed the highest activity against Gram-positive bacteria, especially Streptococcus aureus and Streptococcus pneumoniae belonging to pathogens and Streptococcus epidermidis, Bacilluscereus and Bacillus subtilis belonging to opportunistic microorganisms.

Bacteriophages as an alternative strategy for fighting biofilm development.

The ability of microbes to form biofilms is an important element of their pathogenicity, and biofilm formation is a serious challenge for today's medicine. Fighting the clinical complications associated with biofilm formation is very difficult and linked to a high risk of failure, especially in a time of increasing bacterial resistance to antibiotics. Bacterial species most commonly isolated from biofilms include coagulase-negative staphylococci, Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter spp. The frequent failure of antibiotic therapy led researchers to look for alternative methods and experiment with the use of antibacterial factors with a mechanism of action different from that of antibiotics. Experimental studies with bacteriophages and mixtures thereof, expressing lytic properties against numerous biofilm-forming bacterial species showed that bacteriophages may both prevent biofilm formation and contribute to eradication of biofilm bacteria. A specific role is played here by phage depolymerases, which facilitate the degradation of extracellular polymeric substances (EPS) and thus the permeation of bacteriophages into deeper biofilm layers and lysis of the susceptible bacterial cells. Much hope is placed in genetic modifications of bacteriophages that would allow the equipping bacteriophages with the function of depolymerase synthesis. The use of phage cocktails prevents the development of phage-resistant bacteria.