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AbstractPropolis acts primarily as a biocide against invasive bacteria and fungi in the hive, suggesting its potential for industrial applications. In food application, propolis is considered as a chemical preservative in meat products, extending shelf life of frozen meat and other food. The mechanism of action is still unclear due to the synergy of multiple compounds contained in propolis and due to parallel targeting of multiple pathways within each affected organism. Here, we examined the antimicrobial properties of dimethylsulfoxide (DMSO) Czech propolis extract. Until recently, DMSO was only rarely used in the propolis studies, although the other solvents tested (mostly ethanol) may significantly affect the observed inhibitory effects, notwithstanding the antimicrobial effects of ethanol itself. Here, we provide results of zone inhibition tests against Aspergillus fumigatus, Microsporum gypseum, Microsporum canis, Candida albicans, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Enterococcus faecalis. Although we determined inhibitory effects against all the microorganisms tested, the dose‐dependent response curves were not similar to each other. While inhibitory effects against C. albicans or S. aureus were strictly dose‐dependent, responses of M. gypseum and E. faecalis displayed plateau across the broad range of concentrations tested. Interestingly, response of E. coli revealed the double‐peak dose‐dependent curve, and responses of M. canis and L. monocytogenes decreased at the highest concentrations tested. Suggested is evaluation of DMSO propolis extracts in experimental treatment of human and veterinary infections, preferably in multitherapy with antibiotics.

Using data from Eurobarometer 83.4, this study combines the two branches of research that address climate-related and biodiversity-related opinions and actions of individuals in the EU. The literature shows that the differences between climate-related and biodiversity-related policies correspond, at an individual level, to a person's basic attitudes towards environmental protection and towards nature protection, respectively. The contribution of this study is to demonstrate how these attitudes can influence behavior that has environmental repercussions for both issues, such as food consumption practices. The analysis focused on two Eurobarometer questions about buying local and seasonal food (to fight climate change) and about buying organic and local food (to protect biodiversity and nature). The results of two multinomial regression analyses, separately in Northwestern European countries and Eastern and Southern European countries, demonstrated that climate-related and biodiversity-related attitudes were, independent of each other, related to the adoption of these purchase behaviors. The results may support Europe's new Farm to Fork (F2F) strategy and indicate that improving food consumption practices can enable individuals to better play their part in fighting climate change and biodiversity loss simultaneously, which opens up interesting new perspectives for policymakers, businesses and consumers.

This study investigated the potential of Rhizopus arrhizus UCP 402 for producing chitosan using corn steep liquor and honey as agroindustrial nitrogen and carbon sources. A complete factorial design was used to assess the improved biomass and chitosan production. The results were evaluated using Pareto charts (Statistica 7.0 software). The chitosan obtained was characterized by X-ray diffraction. The cristallinity index (IC), and infrared spectroscopy (FTIR) were used to evaluate the degree of deacetylation (DD %). The morphological aspects of the R. arrhizus were evaluated by measuring the diameter of the colonies by light microscopy. The results obtained showed higher biomass and chitosan yields (20.61 g/L and 29.3 mg/g), respectively, in the selected assays. The characterization of the macromolecular arrangement of chitosan showed a crystallinity index compatible with the literature, and the infrared peaks confirmed a degree of 86%. The experimental data obtained suggest that adding honey to corn steep liquor is a promising way to improve microbiological chitosan production.

Abstract Heterosis, Haldane and Bateson-Dobzhansky-Muller effects have been widely documented amongst a range of plants and animals. However, typically these effects are shown by taking parents of known genotype into the laboratory and measuring components of the F1 progeny under laboratory conditions. This leaves in doubt the real significance of such effects in the field. Here we use the well-known colour pattern genotypes of the African monarch or queen (Danaus chrysippus), which also control wing length, to test these effects both in the laboratory and in a contact zone in the field. By measuring the wing lengths in animals of known colour pattern genotype we show clear evidence for all three hybrid effects at the A and BC colour patterning loci, and importantly, that these same effects persist in the same presumptive F1s when measured in hybrid populations in the field. This demonstrates the power of a system in which genotypes can be directly inferred in the field and highlights that all three hybrid effects can be seen in the East African contact zone of this fascinating butterfly.

Male Wistar albino rats were maintained on alcohol-containing liquid diets for 4 weeks. Hepatic post-mitochondrial preparations derived from these animals were more efficient than control in activating 4-aminobiphenyl and 2-aminofluorene to mutagens in the Ames test. The alcohol-induced enhancement in mutagenicity was not inhibited by dimethylsulphoxide indicating that the generation of hydroxyl radicals is not involved. The activation of 2-naphthylamine was not affected by the treatment with alcohol but the mutagenicities of 2-aminoanthracene, benzo[a]pyrene and 3-methylcholanthrene were inhibited. The same treatment markedly increased hepatic microsomal aniline p-hydroxylase and ethoxyresorufin O-de-ethylase activities and to a lesser extent benzphetamine N-demethylase and microsomal levels of total cytochromes P-450. It is concluded that chronic alcohol administration to rats modulates the metabolic activation of pre-carcinogens to their reactive intermediates presumably by causing the redistribution of cytochrome P-450 isozymes.

In this study the effect of in vivo ethanol consumption on cyclic AMP (cAMP) and [D-Ala2,D-Leu5]enkephalin (DADLE) inhibition of forskolin-stimulated cAMP production was examined in mouse striatum. Effects of ethanol on striatal delta-opioid receptor (DOR) density and mRNA were also examined. Mice had unlimited access to 7% (v/v) ethanol alone or water for 1 or 7 days and were then sacrificed and striatum removed for analysis. There was no difference in basal cAMP formation between water and ethanol-treated mouse striatum following 7 day treatment, and a small, but statistically significant increase in basal cAMP in the ethanol group following 1 day treatment. Both 1 day and 7 day ethanol treatment did not significantly alter the percentage increase in cAMP following treatment with 10 microM forskolin. There was a significant effect of ethanol treatment on the maximum inhibitory effect of DADLE on forskolin-stimulated cAMP formation following both 1 and 7 day ethanol treatment. The DADLE IC50 was unaffected by ethanol treatment. Saturation binding studies ([3H]Deltorphin II) indicated no effect of ethanol on Bmax or Kd in striatum. Similarly, no difference between water and ethanol-treated was observed for DOR mRNA in striatum. These data indicate that ethanol consumption can alter opioid regulation of cAMP formation. However, this effect is not related to changes in any delta-opioid receptor parameters that were examined.

When grown in batch cultures in fermentors with 23.4 mM cellobiose, Clostridium cellulolyticum displayed biphasic growth kinetics not associated with sequential substrate consumption and which led to a twofold higher production of biomass than previously reported. In the first growth phase, acetate was the major product of cellobiose metabolism, since lactate and ethanol productions remained low. Furthermore, an accumulation of intracellular NADH was observed. The transition towards the second growth phase was accompanied by an induction of lactate production, in such a way that lactate became the major product of C. cellulolyticum metabolism. In addition, a decrease in NADH concentration was measured, concomitant with this induction of lactate production and with the growth resumption. During both growth phases, the NADH-ferredoxin reductase-hydrogenase system played a major function in NADH regeneration, since H2 production was 1.4- to 1.5-fold higher than that of CO2. Thus, we found that lactate production serves as an additional catabolic pathway enabling C. cellulolyticum to cope with excesses of carbon and NADH produced. Growth experiments on C. cellulolyticum under an atmosphere of carbon monoxide mimicked this phenomenon and confirmed that a high intracellular level of NADH can provide a barrier to bacterial growth.

Abstract Background Animals co-evolve with their gut microbiota; the latter can perform complex metabolic reactions that cannot be done independently by the host. Although the importance of gut microbiota has been well demonstrated, there is a paucity of research regarding its role in foliage-foraging mammals with a specialized digestive system. Results In this study, a 16S rRNA gene survey and metagenomic sequencing were used to characterize genetic diversity and functional capability of cecal microbiota of the folivorous flying squirrel (Petaurista alborufus lena). Phylogenetic compositions of the cecal microbiota derived from 3 flying squirrels were dominated by Firmicutes. Based on end-sequences of fosmid clones from 1 flying squirrel, we inferred that microbial metabolism greatly contributed to intestinal functions, including degradation of carbohydrates, metabolism of proteins, and synthesis of vitamins. Moreover, 33 polysaccharide-degrading enzymes and 2 large genomic fragments containing a series of carbohydrate-associated genes were identified. Conclusions Cecal microbiota of the leaf-eating flying squirrel have great metabolic potential for converting diverse plant materials into absorbable nutrients. The present study should serve as the basis for future investigations, using metagenomic approaches to elucidate the intricate mechanisms and interactions between host and gut microbiota of the flying squirrel digestive system, as well as other mammals with similar adaptations.