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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]

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]

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 study examined the abundance and prevalence of microscopic fungi genera in the floor and top layers of mineral soil of Quercus robur L., Tilia cordata Mill. and Betula pendula Roth stands. Studies were conducted in 2018, October, after full fall of leaves. By the carbon and nitrogen (C: N) and lignin and nitrogen (Lig: N) ratios, the slowest decompositions were of the Q. robur litter and the fastest - of B. pendula litter. The detection frequency of microscopic fungi in the floor of investigated stands was several times higher than in mineral soil. The highest frequency of fungi detection was of Q. robur floor. The dominance of the Cladosporium Link, Phoma Fr., and Penicillium Link genus was found in the floor of investigated stands. The greater diversity of fungi genera and lower genera population density were found in the top layers of mineral soil (0-4 cm, 5-8 cm). Penicillium fungi were detected in the floor and mineral soil layers of all studied stands. The highest diversity of fungi genera was identified in the mineral soil layers of B. pendula. [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]