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Survival in the soil seed bank is critical to a weed maintaining populations in arable lands. The role of the seed‐borne fungi in seed decay or survival needs to be determined to find solutions for reducing the weed seed banks in environmentally friendly ways. In this study, changes of the fungal microbiome after seed burial were determined in two economically important weed species, wild oat and barnyard grass. Seeds collected in different populations were buried in two sites and exhumed at intervals over the period of 1.5 years to test the seed fate. Epiphytic and endophytic fungal microbiota of seeds was characterised using both culture‐based approach and NGS of ITS1 region. The proportion of visually intact seeds and decayed seeds was different between the two burial sites. The observed species richness of the isolated epiphytic fungi was higher in the fresh compared to the buried seeds. Fungal taxa determined by NGS amplicon sequencing only partly coincided with the isolated fungi, revealing higher diversity in buried seeds. The dynamic of taxonomic structure of the fungal community was less pronounced in wild oat seeds compared to the barnyard grass seeds, where both endophytic and epiphytic communities were significantly different in the buried seeds and differed between the burial sites. It can be concluded that the epiphytic fungal communities change after seed burial in both plant species, while endophytic communities are more stable in the intact seeds and changes of the fungal community in the seed endosphere may be associated with seed decay. [ABSTRACT FROM AUTHOR]

Fluoroalkyl groups play a vital role in pharmaceutical products and agrochemicals, where their installation onto aryl and heterocyclic rings can often lead to enhanced physicochemical and biological properties. Among them, heterocycles containing monofluoromethyl groups are an appealing but scarcely investigated class of organofluorine compounds with potential applications in medicinal chemistry. Here we report that an iodine(III) reagent containing monofluoroacetoxy ligands can be used to transfer monofluoromethyl radicals to heterocycles via visible-light photoredox catalysis, allowing for the mild, direct, and operationally simple modification of medicinally relevant heterocycles through a Minisci-like C–H functionalization process. This approach enriches the synthesis of a structurally diverse set of heteroaromatics incorporating monofluoromethyl groups in moderate to excellent yields. The practicability of direct C–H radical monofluoromethylation for late-stage modifications of medicinally relevant biomolecules and drugs is also demonstrated. Moreover, the monofluoromethylated heterocyclic compounds exhibit promising antimicrobial and anticancer activities, indicating that this methodology might assist in drug discovery as a dependable tool for lead drug modification in the development of new small-molecule drugs. [ABSTRACT FROM AUTHOR]

The objective of this research was to investigate the feasibility of integrating oat (1 → 3, 1 → 4)-β-D-glucan (β-glucan) dried by two different techniques (freeze drying and spray drying) into a synbiotic formulation with Akkermansia muciniphila. The study evaluated the impact of this synbiotic formulation on the growth of A. muciniphila and its effect on the fermentation process. The extracted oat β-glucans underwent freeze-drying (FD) and spray-drying (SD) processes before being introduced as supplementary carbon sources (1%) to brain heart infusion (BHI) medium containing A. muciniphila MSCL 1582. The BHI medium containing inulin, D-glucose, and BHI without added substrates served as the control. Bacterial growth and short-chain fatty acid (SCFA) production were measured before and after 72 h of fermentation. A light microscope and KOVA slides were used for the A. muciniphila count, and SCFA levels were measured via gas chromatography. Our findings revealed that oat β-glucans could effectively function as prebiotic substrates in complementary synbiotic composition with A. muciniphila, without inhibiting growth and causing metabolic impairment. Both FD and SD techniques demonstrated equivalent and favorable impacts on the fermentative capacity of A. muciniphila, rendering them suitable choices for the drying of β-glucans. Incorporating oat β-glucan into synbiotic formulations offers potential benefits, contributing to A. muciniphila growth and the fermentation process. [ABSTRACT FROM AUTHOR]

The twigs of sea buckthorn, blackcurrant, gooseberries, quince, and grapes were evaluated as a promising source of biologically active compounds—proanthocyanidins (PACs). Sea buckthorn twigs had the highest content of PACs (9.2% on dry biomass). Preliminary pretreatment of biomass with freon R134a did not allow an increase in PACs content in the composition of hydrophilic extract but confirmed the value of freon extract as an antibacterial agent against P. aeruginosa and B. cereus. The content of PACs was used as an indicator for assessment of the influence of hydrophilic extracts on pancreatic lipase activity. Under normal physiological conditions, in the presence of bile, the extract, which contained 42.4% of PACs was more effective compared to the extract which contained 17.5% of PACs. At all concentrations (0.2–40 mg of sample/g of pancreatic lipase), it inhibited lipase activity by 33%. Purified PACs were the most effective in inhibiting lipase activity (by 36%). However, in pathological physiological conditions (without bile), the opposite effect on lipase activity was observed. Thus, PACs and extracts can be used as inhibitors of pancreatic lipase only under normal physiological conditions. [ABSTRACT FROM AUTHOR]

The reduction of tissue cytotoxicity and the improvement of cell viability are of utmost significance, particularly in the realm of green chemistry. Despite substantial progress, the threat of local infections remains a concern. Therefore, hydrogel systems that provide mechanical support and a harmonious balance between antimicrobial efficacy and cell viability are greatly needed. Our study explores the preparation of physically crosslinked, injectable, and antimicrobial hydrogels using biocompatible hyaluronic acid (HA) and antimicrobial ε-polylysine (ε-PL) in different weight ratios (10 wt% to 90 wt%). The crosslinking was achieved by forming a polyelectrolyte complex between HA and ε-PL. The influence of HA content on the resulting HA/ε-PL hydrogel physicochemical, mechanical, morphological, rheological, and antimicrobial properties was evaluated, followed by an inspection of their in vitro cytotoxicity and hemocompatibility. Within the study, injectable, self-healing HA/ε-PL hydrogels were developed. All hydrogels showed antimicrobial properties against S. aureus, P. aeruginosa, E. coli, and C. albicans, where HA/ε-PL 30:70 (wt%) composition reached nearly 100% killing efficiency. The antimicrobial activity was directly proportional to ε-PL content in the HA/ε-PL hydrogels. A decrease in ε-PL content led to a reduction of antimicrobial efficacy against S. aureus and C. albicans. Conversely, this decrease in ε-PL content in HA/ε-PL hydrogels was favourable for Balb/c 3T3 cells, leading to the cell viability of 152.57% for HA/ε-PL 70:30 and 142.67% for HA/ε-PL 80:20. The obtained results provide essential insights into the composition of the appropriate hydrogel systems able to provide not only mechanical support but also the antibacterial effect, which can offer opportunities for developing new, patient-safe, and environmentally friendly biomaterials. [ABSTRACT FROM AUTHOR]

To address the need to reduce consumption and pollution in the industrial sector, composite materials were created using a new type of raw materials—organic lake sediments (sapropel) as a binder; sphagnum moss, flax fiber, and vermiculite as a filler. The main application of these composite materials is for sound absorption and moisture buffering, but since they contain bio-based binders and fillers, they also work as carbon storage. Within the framework of this work, a total of 100 samples of composite materials were created. Fungicides—a biocide quaternary ammonium compound and its natural substitute montmorillonite mineral material were also added to the materials to improve microbiological stability. The mechanical sound absorption and microbiological properties of materials were investigated and compared to similar environmentally friendly materials, such as hemp-lime concrete (FHL), hemp magnesium oxychloride composite (MOC), and hemp magnesium phosphate cement (MPC). The results showed that sound absorption and mechanical and microbial properties of the created composite materials are sufficient for their intended use, with flax fiber and vermiculite composites showing more stable mechanical, sound absorbing, and microbiological stability properties than materials containing flax fiber and moss. [ABSTRACT FROM AUTHOR]

It has now been proven that many pathogens that cause infections and inflammation gradually mutate and become resistant to antibiotics. Chemically synthesized drugs treating inflammation most often only affect symptoms, but side effects could lead to the failure of human organs' functionality. On the other hand, plant-derived natural compounds have a long-term healing effect. It was shown that sea buckthorn (SBT) twigs are a rich source of biologically active compounds, including oligomeric proanthocyanidins (PACs). This study aimed to assess the anti-pathogenic and anti-inflammatory activity of water/ethanol extracts and PACs obtained from the lignocellulosic biomass of eight SBT cultivars. The anti-pathogenic activity of extracts and PACs was studied against pathogenic bacteria Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Bacillus cereus and fungus Candida albicans in 96-well plates by the two-fold serial broth microdilution method. The anti-bacterial activity of purified PACs was 4 and 10 times higher than for water and water/ethanol extracts, respectively, but the extracts had higher anti-fungal activity. Purified PACs showed the ability to reduce IL-8 and IL-6 secretion from poly-I:C-stimulated peripheral blood mononuclear cells. For the extracts and PACs of SBT cultivar 'Maria Bruvele' in the concentration range 0.0313–4.0 mg/mL, no toxic effect was observed. [ABSTRACT FROM AUTHOR]

This study examined the distribution of culturable fungi and predominant genera in the organic layer and in the upper layers of the mineral soil of six broad-leaved tree plantations in autumn, after the full fall of leaves. In total, 1335 fungal isolates were recovered from an organic layer and two mineral layers (0–4 cm and 5–8 cm) of soil. The structure of fungal genera differed in the tree plantations and in the three studied soil layers. The organic layer was the layer most populated by fungi compared to the mineral layers. In the organic layer, Penicillium and phyllosphere fungi such as Cladosporium and Phoma dominated. Deeper in the soil, the dominance of certain genera decreased with the increase in Trichoderma, Mucor, Mortierella, and entomopathogenic fungi such as Paecilomyces and Beauveria. Penicillium was one of the most abundant fungi in all soil layers studied. [ABSTRACT FROM AUTHOR]

Fungi colonizing the surface and endosphere of two widespread Poaceae weed species, Avena fatua and Echinochloa crus-galli, were isolated to compare the taxonomic composition between the plant species, location, and year of the seed collection. The seed-degrading potential of Fusarium isolated from the seeds was tested by inoculating seeds of E. crus-galli with spore suspension. Molecular identification of epiphytic and endophytic fungal genera was performed by sequencing the ITS region of rDNA. Endophytes comprised of significantly lower fungal richness compared to epiphytes. A significant taxonomic overlap was observed between the endosphere and seed surface. The most abundant genera were Alternaria, Fusarium, Cladosporium, and Sarocladium. Analysis of similarities and hierarchical clustering showed that microbial communities were more dissimilar between the two plant species than between the years. Fusarium isolates with a high potential to infect and degrade E. crus-galli seeds in laboratory conditions belong to F. sporotrichioides and F. culmorum. [ABSTRACT FROM AUTHOR]

The aim of this paper was to study the microbiological stability of bio-based composite building materials, which are made using organic-rich lake sediments (further - sapropel) with lime and magnesium cement as binders and hemp shives as filler. The microbial stability properties of the obtained composite materials were investigated and compared to similar composites. Because of their high organic content, these materials are prone to biodegradation; therefore, they were coated with ALINA LIFE TM organoclay coating, which helps to extend the product life, reducing the rate of biodegradation compared to the biocides used in industry. The effect of the coating on the resistance to decay by the Aspergillus versicolor, Penicillium chrysogenum, Alternaria alternata, Cladosporium herbarum, Chaetomium sp. and Trichoderma asperellum fungi was investigated under different conditions: relative humidity modes of 75% and 99% at 20°C for 45 days and four months. The results indicated that the composites made of sapropel and lime have similar microbial stability properties as lime and magnesium cement binder composite materials. ALINA LIFE TM organoclay coating showed advanced resistance to biodegradation; sapropel-lime composites have shown several good properties that make them suitable to be considered for use in the construction material industry. [ABSTRACT FROM AUTHOR]

Listeria monocytogenes is a well-known psychrotrophic food pathogen. The aim of the study was to evaluate the growth potential of L. monocytogenes in two ready-to-eat cold smoked sausages with and without starter cultures. The goal was achieved using the microbiological challenge test. Sausage samples were artificially contaminated with L. monocytogenes and stored at 4 ± 2 °C for 30 days. No increase in L. monocytogenes was observed and its concentration in the fermented sausages "Cigarellas" decreased by approximately log 0.1 per day. Significant growth of listeria was observed by day 21 in non-fermented sausages "Barona". In the following days the amount of listeria gradually decreased, and after 28 days it did not differ from the initial amount. The growth potential of L. monocytogenes in "Cigarellas" and "Barona" was zero and 0.4, respectively. The products tested were unable to support the growth of listeria. Thus, they can be classified as "Ready-to-eat food unable to support the growth of Listeria monocytogenes". Despite the low growth potential, it is desirable to expand the fermentation of uncooked ready-to-eat sausages to achieve zero tolerance for L. monocytogenes. [ABSTRACT FROM AUTHOR]

Treatment of freshly cut stumps with biological control agents containing Phlebiopsis gigantea spores effectively restricts the spread of new Heterobasidion infections in conifer forests. To test the control efficacy of different P. gigantea strains, conifer stumps or billets cut from tree stems can be artificially infected with asexual Heterobasidion conidiospores or sexual basidiospores or left for natural basidiospore infection. Currently, no information is available about whether the control efficiency of P. gigantea in Norway spruce wood is affected by Heterobasidion spore type. In the present study, the impact of four P. gigantea strains (including the commercial product Rotstop®) on initiation and development of Heterobasidion basidiospore and conidiospore infections as well as the relationship between the area occupied by P. gigantea and control efficacy were analysed in spruce billets. The mean size of the area occupied by P. gigantea was larger, and the efficacy of P. gigantea against Heterobasidion was significantly higher in billets left for natural basidiospore infection compared to treatment with Heterobasidion conidiospore suspension. The control efficacy against Heterobasidion infection was high, although only a small area of the billet surface was occupied by P. gigantea and even when there was no visible discoloration caused by P. gigantea infection on wood surfaces. [ABSTRACT FROM AUTHOR]

The article discusses the possible relationships between intestinal microbiota and the therapeutic efficacy of 5-aminosalicylic acid (5-ASA) in inflammatory bowel diseases. Intestinal microbiota may be involved in 5-ASA enzymatic biotransformation, but the metabolism of drugs by the intestinal microbiota has been studied in less detail, and little is known about the relationships between anti-inflammatory efficacy of 5-ASA with bacterial viability, quantity and activity. It remains unclear whether 5-ASA affects the microbiota depending on the different segments of gastrointestinal tract. Drugs and diet can both improve and worsen the composition of the intestinal microbiota. However, it is not known whether drugs affect the intestinal microbiota regardless of diet. Further research is needed to answer these questions. [ABSTRACT FROM AUTHOR]

Although the information available on pathogenic Escherichia coli is in abundance, foodborne outbreaks are still a major problem. The aim of this study was to describe E. coli strains isolated from cold smoked meat products (37 samples) and sprouted grains (35 samples), to evaluate their virulence potential (vtx1, vtx2; eaeA), to determine serogroups and antibiotic resistance in Latvia. From the isolates tested 66 samples (91.7%) contained none of the virulence genes, 6 samples (8.3%) contained the eaeA gene, and two samples (2.8%) contained eaeA and vtx1 genes. Eleven samples (29.7%) isolated from meat products belonged to serogroups O103, O121, O145, O142, and O26. Six strains contained the eaeA gene, and four of them belonged to serogroup O103, one to O145, and one to O26. Two strains that additional to eaeA gene were also positive to vtx1 belonged to verotoxigenic O26. 31 samples (88.6%) isolated from sprouted grains belonged to serogroups O103 and O121; however, none of the strains contained any of the virulence genes. From strains isolated from meat products 46.0% were resistant to one to three antibiotics, but all isolates from sprouted grains were susceptible. Two strains showed multi-resistance and also contained the mcr-1 gene that encodes resistance to colistin. [ABSTRACT FROM AUTHOR]

Biological fertilizers are being developed on the basis of plant growth promoting microorganisms isolated from the plant rhizosphere, phyllosphere and endosphere. The aim of this study was to determine influence of a consortium of plant endophytes on rhizosphere microbiota in a greenhouse vegetation experiment with barley. Fifty-five bacterial and fungal strains were isolated from leaves, stems and roots of oilseed rape and barley. Twentty five of them did not inhibit seed germination. Most of them belonged to the genera Serratia, Enterobacter, Brevibacillus and Pseudomonas. Individual isolates demonstrated phosphate solubilization ability, nitrification potential and urease activity. Impact of the multi-strain microbial consortium on cultivable microbiota of rhizosphere was estimated in a 19-day greenhouse experiment with barley. Concentration of phosphate solubilizing and cellulolytic microorganisms in the rhizosphere was below the detection limit. The consortium increased the total number of bacterial colony-forming units but did not affect the number of actinobacterial and fungal colony-forming units. Interactions between species in the multi-strain consortium and between introduced and indigenous populations are discussed. [ABSTRACT FROM AUTHOR]

The aim of this study was to characterize the digestate from an activated sludge biogas reactor (IDARS) as an inoculum for enzymatic hydrolysis and biogas production from organic wastes. Aerobic and anaerobic bacteria are represented in IDARS with H' index 3.1 and 2.5, respectively. IDARS stimulated the enzymatic hydrolysis of wood and leaves, preferably broadleaf tree species. The results demonstrated the potential of IDARS for improvement of the technological parameters for conversion of organic wastes into biogas. [ABSTRACT FROM AUTHOR]

Entrapment in alginate gel is a widely used approach for immobilization of microorganisms to improve their viability. A natural bacterial association consisting of seven strains isolated from acid tar-contaminated soil was used for immobilization in alginate gel. The aim of this study was to identify conditions for entrapment of a bacterial association and to determine conditions for its prolonged storage. The association was successfully immobilized in 1.5% alginate beads that were 2 mm in diameter. All tested treatments, with or without 5% clay, with or without 10% glycerol, and with or without incubation of prepared beads in nutrient medium or 0.2 M solution of CaCl2, showed good results in terms of survival of bacteria immediately after entrapment in gel and during at least six months storage of beads at temperature of 4 and 20 °C. The number of bacterial colony-forming units increased by 1.1 to 1.3 log g-1 in clay-containing beads during the experiment, regardless of storage temperature but it remained at baseline levels in other treatments. Further studies are necessary to evaluate bioremediation activities of the immobilized association in laboratory and field conditions. [ABSTRACT FROM AUTHOR]

Heterobasidion annosum (Fr.) Bref. s.l. causes significant economic losses in conifer forests. Therefore, to reduce the spread of the infection surfaces of freshly cut conifer, stumps are commonly treated with biological control agents. Trichoderma sp. shows very strong antagonistic effect against H. annosum in vitro, but relatively few field studies have been conducted. Moreover, most of previous studies examined the impact of Trichoderma sp. on H. annosum in healthy conifer stumps. The aim of our work was to evaluate the effect of Trichoderma sp. against H. annosum in already decayed understory spruce stumps. In total, 75 decayed spruce stumps were surveyed. Part of the spruce stumps were left as a control, and the others were treated with one of two Trichoderma isolates (T472 and T945) belonging to two different species: T. viridescens and T. viride. The occurrence of H. annosum was evaluated 3 and 12 months after treatment. The main results were that the area of previously healthy wood occupied by H. annosum was larger in control stumps in comparison with treated stumps, but the differences were not statistically significant. [ABSTRACT FROM AUTHOR]

Fungal endophyte community amplicon sequencing can lose a significant number of informative reads due to host-plant co-amplification. Blocking of plant-specific sequences with peptide nucleic acid (PNA) clamps has been shown to improve metrics of detected microbial diversity in studies targeting 16S and 18S regions of rRNA genes. However, PNA clamping has not been applied to the plant ITS region of rRNA gene – a widely accepted fungal marker. By applying PNA clamping technique to ITS amplicon sequencing of the endophytic fungal community of elderberry this study shows that PNA clamping significantly reduces host-plant co-amplification with the universal ITS1/ITS4 primer set. However, PNA clamping in combination with the discriminatory ITS1F/ITS2 primer set did not improve the metrics of fungal endophyte community ITS amplicon Illumina sequencing. This study shows that PNA clamping does not add practical benefit to taxonomic profiling of plant-associated fungal communities if the primers are already specific enough to exclude amplification of host DNA. • PNA clamping of host-plant DNA can be applied to fungal marker locus ITS1. • PNA clamping is beneficial in combination with universal ITS1/ITS4 primer set. • PNA clamping did not improve performance of specific Illumina ITS1F/ITS2 primer set. • Results challenge the practicality of PNA clamping for ITS Illumina sequencing. [ABSTRACT FROM AUTHOR]

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Mosses have been neglected as a study subject for a long time. Recent research shows that mosses contain remarkable and unique substances with high biological activity. The aim of this study, accordingly, was to analyze the composition of mosses and to screen their antimicrobial and anticancer activity. The total concentration of polyphenols and carbohydrates, the amount of dry residue and the radical scavenging activity were determined for a preliminary evaluation of the chemical composition of moss extracts. In order to analyze and identify the substances present in mosses, two types of extrahents (chloroform, ethanol) and the GC/MS and LC-TOF-MS methods were used. The antimicrobial activity was tested on four bacteria strains, and the anticancer activity on six cancer cell lines. The obtained results show the presence of a high number of primary (fatty acids and amino acids), but mainly secondary metabolites in moss extracts-including, sterols, terpenoids, polyphenols and others-and a high activity with respect to the studied test organisms. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles represent an advanced tool in biomedicine because they can be simultaneously functionalized and guided using amagnetic field. Iron oxide magnetic nanoparticles precoated with oleic acid and bearing novel antimicrobialN-heterocyclic choline analogues, namely O-, N- and O,N-bis-undecyl-substituted N-(2-hydroxyethyl)-1,2,3,4-tetrahydroisoquinolinium derivatives, have been obtained as potential biomedical agents for drug delivery and antimicrobial therapy. Structural and size determinations for the novel synthesized magnetic nanosystems were carried out based upon magnetogranulometry, dynamic light-scattering measurements and X-ray diffraction analysis. The most expected iron oxide core diameter was 6.2-10.5nm. The magnetization analyses showed that the particles are superparamagnetic at room temperature. Aqueous magnetic fluids of the synthesized nanoparticles were examined in vitro concerning Gram-positive (Staphylococcus aureus MSCL 334, Bacillus cereus MSCL 330) and Gram-negative (Escherichia coli MSCL 332, Pseudomonas aeruginosa MSCL 331, Proteus mirabilis MSCL 590) bacterial strains and fungi (Candida albicans MSCL 378, Aspergillus niger MSCL 324). It was found that the samples havemagnetic properties and possess antimicrobial activity. The minimum inhibitory concentration against S. aureus for the most active magnetic fluid was determined as 16 μgml-1. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings of the Estonian Academy of Sciences is the property of Teaduste Akadeemia Kirjastus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For sustainable sea buckthorn (Hippophae rhamnoides) berry production, the task at hand is to find an application for the large amount of biomass waste arising at harvesting. Sea buckthorn (SBT) vegetation is currently poorly studied. The purpose of this research was to assess the composition and potential of SBT twigs as a source of valuable biologically active substances. Water and 50% EtOH extracts of twigs of three Latvian SBT cultivars with a high berry yield and quality, popular for cultivation in many countries (H. rhamnoides 'Maria Bruvele', 'Tatiana', 'Botanicheskaya Lubitelskaya'), were investigated for the first time. The phytochemical composition (UHPLC-ESI-MS/MS analysis) and biological activity of the obtained hydrophilic extracts were determined. The highest yield of polyphenolic compounds and serotonin was observed for 'Maria Bruvele'. Hydrophilic extracts were investigated for radical scavenging activity (DPPH˙ test), antibacterial/antifungal activity against five pathogenic bacteria/yeast, cytotoxicity, and the enzymatic activity of alpha-amylase (via in vitro testing), which is extremely important for the treatment of people with underweight, wasting, and malabsorption. The results showed a high potential of sea buckthorn biomass as a source of valuable biologically active compounds for the creation of preparations for the food industry, nutraceuticals, and cosmetics. [ABSTRACT FROM AUTHOR]

A series of N-methyl- N-(2-triorganylsiloxyethyl)-1,2,3,4-tetrahydro(iso)quinolinium iodides has been synthesized via dehydrocondensation reaction of N-(2-hydroxyethyl)-1,2,3,4-tetrahydroisoquinoline, N-(2-hydroxyethyl)-1,2,3,4-tetrahydroquinoline and 4,4-dimethyl- N-(2-hydroxyethyl)-4-sila-1,2,3,4-tetrahydroisoquinoline with trialkyl(aryl)hydrosilanes and subsequent alkylation, and characterized by 1H, 13C and 29Si NMR and mass spectroscopy. The biological activity data exhibited a marked enhancement of inhibitory activity against tumour cell lines and almost all the test bacterial/fungal strains in comparison with their 2-hydroxyethyl precursors. Cytotoxicity in the microgram range against HT-1080 (human fibrosarcoma) and MG-22A (mouse hepatoma) cancer cell lines was observed for most of compounds. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Copyright of Estonian Journal of Ecology is the property of Teaduste Akadeemia Kirjastus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Estonian Journal of Ecology is the property of Teaduste Akadeemia Kirjastus and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: In this study, a microbiological challenge test in three artificially contaminated retail mixed mayonnaise-based ready-to-eat salads stored at refrigerator temperatures (3°C and 7°C) for 48h was carried out. Shrimp–tomato salad, smoked ham salad and garlic cheese salad were separately contaminated by a suspension of particular Listeria monocytogenes strains. The number of L. monocytogenes, Enterobacteriaceae, staphylococci and total plate count (CFU/g) was determined. Listeria monocytogenes growth potential in the salads was calculated and evaluated. A significant increase in total plate count and L. monocytogenes count throughout storage of all three investigated salads was found. Enterobacteriaceae levels were high at the beginning in all salads but significantly (p <0.05) decreased throughout the experiment depending on the temperature. All investigated L. monocytogenes strains demonstrated growth at both temperatures but expressed different growth potential. Especially garlic cheese salad and smoked ham salad were able to support the growth of Listeria. Shrimp–tomato salad supported growth the least. The growth potential increased with the increasing temperature and exceeded 0.5 log10 CFU/g in many cases. If the potential for growth is >0.5 log10 CFU/g, food products can potentially endanger human health. Reference strain (ATCC 7644) showed the least growth potential almost in all cases in comparison with strains isolated from frozen pollock loins and from thermally treated specialty sausage containing preservatives. To eliminate the occurrence of microbiological risks, the shelf-life of the studied salads was estimated. [ABSTRACT FROM AUTHOR]

Copyright of Material Science & Applied Chemistry is the property of RTU Publishing House and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacterial infections are a prevalent complication after primary viral respiratory infections and are associated with high morbidity and mortality. Antibiotics are widely used against bacterial respiratory pathogens; however, the rise in antibiotic-resistant strains urges us to search for new antimicrobial compounds, including ones that act synergistically with antibiotics. In this study, the minimal inhibitory (MIC) and minimal bactericidal (MBC) concentrations of a polyphenol-rich complex of green propolis, Tabebuia avellanedae bark, and Olea europaea leaf extracts against Staphylococcus aureus, Haemophilus influenzae, and Klebsiella pneumoniae were determined, followed by an analysis of the synergistic effect with clarithromycin, azithromycin, and amoxiclav (875/125 mg amoxicillin/clavulanic acid). A combination of extracts showed activity against all three bacterial strains, with MIC values ranging from 0.78 to 12.5 mg/mL and MBC values from 1.56 to 12.5 mg/mL. The extracts showed synergistic activity with azithromycin and clarithromycin against S. aureus, with clarithromycin against K. pneumoniae, and with all three tested antibiotics against H. influenzae. Synergy with clarithromycin was additionally evaluated in a time-kill assay where the synergistic effects against S. aureus and K. pneumoniae were seen within the first 6 h of incubation. The results show the potential of polyphenol-rich extracts in enhancing the efficacy of antibiotic therapy and indicate their potential to be used in the management of respiratory infections. [ABSTRACT FROM AUTHOR]