Biologia futura最新文献

Maize dwarf mosaic virus (MDMV) can significantly reduce the growth and development of susceptible varieties of sweet corn. The virus utilises the energy and reserve sources of plant cells to ensure its reproduction in the microspaces formed by cell membranes. Therefore, the severity of stress can be monitored by examining certain physiological changes, for example, changes in the degree of membrane damage caused by lipid peroxidation, as well as changes in the amount of photosynthetic pigments. The activation of antioxidant enzymes (e.g. ascorbate peroxidase, guaiacol peroxidase, glutathione reductase) and the accumulation of phenolic compounds with antioxidant properties can indirectly protect against the oxidative stress caused by the presence of the positive orientation, single-stranded RNA-virus. This study demonstrates the changes in these physiological processes in a sweet corn hybrid (Zea mays cv. saccharata var. Honey Koern.) susceptible to MDMV infection, and suggests that exogenous small RNA treatment can mitigate the damage caused by virus infection.

Young shoots of cereals are widely regarded as superfoods with health benefits attributed to their potential antioxidant activity and antioxidant-related effects (e.g. anticancer). The current study aimed to examine the chemical characteristics of Hordeum vulgare methanolic and aqueous extracts and assess their antioxidant activity using the DDPH and ORAC. Furthermore, the inhibitory effect of xanthine oxidase was screened. TLC bioautography was employed to determine the polarity of the compounds present in the extracts that exhibited the most potent free radical scavenging activity. Total flavonoid content of the methanolic and aqueous extracts was 0.14 mg QE/g and 0.012 mg QE/g, respectively. The antioxidant activity of the methanolic extract was found to be more potent, with a value of 0.97 ± 0.13 mmol TE/g than the aqueous extract which had no activity. This study presents novel findings on the xanthine inhibitory activity of H. vulgare. The methanolic extract demonstrated moderate inhibition of xanthine oxidase with a value of 23.24%. The results of our study were compared with the phytochemical and pharmacological analysis of Triticum aestivum, and further comparison was made with the data reported in the literature. Inconsistencies were observed in the chemical and pharmacological properties of H. vulgare, which could be a result of using herbal material harvested in different vegetative phases and various methods used for extraction. The findings of our study indicate that the timing of the harvest and extraction method may play crucial role in attaining the optimal phytochemical composition of H. vulgare, hence enhancing its pharmacological activity.

Potato (Solanum tuberosum) is considered worldwide as one of the most important non-cereal food crops. As a result of its adaptability and worldwide production area, potato displays a vast phenotypical variability as well as genomic diversity. Chloroplast genomes have long been a core issue in plant molecular evolution and phylogenetic studies, and have an important role in revealing photosynthetic mechanisms, metabolic regulations and the adaptive evolution of plants. We sequenced the complete chloroplast genome of the Hungarian cultivar White Lady, which is 155 549 base pairs (bp) in length and is characterised by the typical quadripartite structure composed of a large- and small single-copy region (85 991 bp and 18 374 bp, respectively) interspersed by two identical inverted repeats (25 592 bp). The genome consists of 127 genes of which 82 are protein-coding, eight are ribosomal RNAs and 37 are transfer RNAs. The overall gene content and distribution of the genes on the White Lady chloroplast was the same as found in other potato chloroplasts. The alignment of S. tuberosum chloroplast genome sequences resulted in a highly resolved tree, with 10 out of the 13 nodes recovered having bootstrap values over 90%. By comparing the White Lady chloroplast genome with available S. tuberosum sequences we found that gene content and synteny are highly conserved. The new chloroplast sequence can support further studies of genetic diversity, resource conservation, evolution and applied agricultural research. The new sequence can support further potato genetic diversity and evolutionary studies, resource conservation, and also applied agricultural research.

Growing human population and increasing urbanization call for the need for proper wastewater treatment to reduce environmental pollution and reduce the excess use of natural resources. During the collection of municipal wastewater, the rapid aerobic respiration often causes oxygen depletion and anaerobic conditions in the sewer system resulting in the production of malodorous compounds. The odor problems may lead to public complaints, or in the case of the sewage workers the released volatile compounds even cause serious health hazards. Therefore, microbes have a dual contribution in the urban water cycle, since they have a decisive role in wastewater treatment and the removal of pollutants, but they can also cause problems in the artificial environment. In this review, I would like to summarize the processes underlying the generation of the bad smell associated with sewage and wastewater or with the collection and treatment infrastructure, tracking the way from the households to the plants, including the discussion of processes and possible mitigation related to the released hydrogen sulfide, volatile organics and other compounds.

Endocrine disruptors are potential environmental contaminants that can cause toxicity in aquatic ecosystems, so the Water Framework Directive has established limits for these compounds. During our research, 41 bacterial strains were isolated and identified from sewage effluent and tested for their degradation capacities for bisphenol A, 17β-estradiol, and nonylphenol. All the isolated bacteria belonged to the Gammaproteobacteria class of Pseudomonadota phylum (members of Citrobacter, Enterobacter, Escherichia, Klebsiella, Kluyvera, Leclercia, Raoultella, Shigella. Acinetobacter, Aeromonas, and Pseudomonas genera). During the experiments, only strains HF17, HF18 (Pseudomonas aeruginosa), and HF31 (Citrobacter freundii) were unable to grow on these compounds, all other bacterial strains could grow in the presence of the investigated endocrine disruptors. Based on the genomic analysis of the type strains, a set of genes involving aromatic compound degradation was detected, among the peripheral metabolic pathways, the quinate and benzoate degradation pathways proved to be widespread, among the central aromatic intermediates metabolism, the catechol branch of the beta-ketoadipate pathway was the most dominant. Pseudomonas fulva HF16 strain could utilize the investigated endocrine disruptors: bisphenol A by 34%, 17β-estradiol by 52%, and nonylphenol by 54%.

In response to COVID-19 pandemic, governments all over the world limited the movement of people and mandated temporary closure of different institutions. While, these measures helped to reduce the spread of COVID-19, stagnant water can cause water quality deterioration. Stagnation is considered in context with the proliferation of pathogenic and facultatively pathogenic bacteria which pose potential health risks to humans. The objective of this study was to document the hygienic microbiological status of different water systems after the first shutdowns (between 18th March 2020 and 18th May 2020) in Hungary in comparison with a reference period (between 3rd January 2020 to 17th March). During the reference period drinking waters were compliant > 95% of total samples to the parametric values. After the short period shutdowns, the ratio of tnon-compliant drinking water samples was 6.6%: mainly Pseudomonas aeruginosa (7%) and coliform bacteria (5%) resulted poor water quality. The microscopic analysis of drinking waters showed that after low water demand the values of non-compliant samples also increased due to the proliferation of Amoebozoa and other Protozoa species. The compliant pool waters' ratio was also high in the reference period (97-99%), while after the shutdowns more samples were positive in both pool operation type (fill-and-drain pools and pools with recirculation) due to the proliferation of P. aeruginosa (14%) and micrococci (12%). Legionella non-compliant samples in hot tap water did not show significant difference during both studied periods (15%) although after stagnation the Legionella CFU (colony forming unit) values of the samples increased markedly.

Earth harbors unique environments where only microorganisms adapted to extreme conditions, known as extremophiles, can survive. This study focused on a high-altitude meltwater pond, located in the Puna de Atacama, Dry Andes. The extremophilic bacteria of this habitat must adapt to a range of extremities, including cold and dry climate, high UV radiation, high daily temperature fluctuations, low-nutrient availability, and negative water balance. This study aimed to explore the taxonomic diversity of cultivable extremophilic bacteria from sediment samples of a desiccated, high-altitude, meltwater pond using media with different organic matter contents and different incubation temperatures. Based on the 16S rRNA gene sequence analysis, the isolates were identified as members of the phyla Actinobacteria, Proteobacteria, and Firmicutes. The most abundant genera were Arthrobacter and Pseudoarthrobacter. The isolates had oligocarbophilic and psychrotrophic properties, suggesting that they have adapted to the extreme environmental parameters of their natural habitats. The results indicate a positive correlation between nutrient concentration and temperature tolerance.

Salinization and sodification are serious and worldwide growing threats to healthy soil functions. Although plants developed a plethora of traits to cope with high salinity, soil bacteria are also essential players of the adaptation process. However, there is still lack of knowledge on how other biotic and abiotic factors, such as land use or different soil properties, affect the bacterial community structure of these soils. Therefore, besides soil chemical and physical investigations, bacterial communities of differently managed salt-affected soils were analysed through 16S rRNA gene Illumina amplicon sequencing and compared. Results have shown that land use and soil texture were the main drivers in shaping the bacterial community structure of the Hungarian salt-affected soils. It was observed that at undisturbed pasture and meadow sites, soil texture and the ratio of vegetation cover were the determinative factors shaping the bacterial community structures, mainly at the level of phylum Acidobacteriota. Sandy soil texture promoted the high abundance of members of the class Blastocatellia, while at the slightly disturbed meadow soil showing high clay content was dominated by members of the class Acidobacteriia. The OTUs belonging to the class Ktedonobacteria, which were reported mostly in geothermal sediments, reached a relatively high abundance in the meadow soil.

Epilithic biofilms are ubiquitous in large river environments and are crucial for biogeochemical processes, but their community structures and functions remain poorly understood. In this paper, the seasonal succession in the morphological structure and the taxonomic composition of an epilithic bacterial biofilm community at a polluted site of the Danube River were followed using electron microscopy, high-throughput 16S rRNA gene amplicon sequencing and multiplex/taxon-specific PCRs. The biofilm samples were collected from the same submerged stone and carried out bimonthly in the littoral zone of the Danube River, downstream of a large urban area. Scanning electron microscopy showed that the biofilm was composed of diatoms and a variety of bacteria with different morphologies. Based on amplicon sequencing, the bacterial communities were dominated by the phyla Pseudomonadota and Bacteroidota, while the most abundant archaea belonged to the phyla Nitrososphaerota and Nanoarchaeota. The changing environmental factors had an effect on the composition of the epilithic microbial community. Critical levels of faecal pollution in the water were associated with increased relative abundance of Sphaerotilus, a typical indicator of "sewage fungus", but the composition and diversity of the epilithic biofilms were also influenced by several other environmental factors such as temperature, water discharge and total suspended solids (TSS). The specific PCRs showed opportunistic pathogenic bacteria (e.g. Pseudomonas spp., Legionella spp., P. aeruginosa, L. pneumophila, Stenotrophomonas maltophilia) in some biofilm samples, but extended spectrum β-lactamase (ESBL) genes and macrolide resistance genes could not be detected.

Chlorinated ethenes are toxic compounds that were widely used in the past, and their improper handling and storage caused notable pollutions worldwide. In situ bioremediation by reductive dechlorination of bacteria is a cost-effective and ecologically friendly way to eliminate these pollutions. During the present study, the efficiency of a previously developed bioaugmentation agent combined with biostimulation was tested under field conditions in contaminated soil. Furthermore, the preservation of dechlorinating ability was also investigated in a long-term experiment. Initially, aerobic conditions were present in the groundwater with possible presence of anaerobic micro-niches providing habitat for Brocadia related anammox bacteria. "Candidatus Omnitrophus" was also identified as a dominant member of community then. Significant changes were detected after the biostimulation, anaerobic conditions established and most of the dominant OTUs were related to fermentative taxa (e.g. Clostridium, Trichococcus and Macillibacteroides). Dominant presence of vinyl-chloride coupled with the lack of vinyl-chloride reductase gene was observed. The most notable change after the bioaugmentation was the significant decrease in the pollutant quantities and the parallel increase in the vcrA gene copy numbers. Similar to post-biostimulation state, fermentative bacteria dominated the community. Bacterial community composition transformed considerably with time after the treatment, dominance of fermentative-mainly Firmicutes related-taxa decreased and chemolithotrophic bacteria became abundant, but the dechlorinating potential of the community remained and could be induced by the reappearance of the pollutants even after 4 years.