Filters
Diversity of Bacterial Communities in Horse Bean Plantations Soils with Various Cultivation Technologies
Modern agriculture should limit its degrading impact on the soils, the natural environment, and the climate. No-tillage soil cultivation technologies, which have been in use for many years and are constantly being improved, are a good example of these actions; although, in-depth studies on their impact on the soil microbial community are currently scarce. The aim of our study was to evaluate the effect of cultivation technology on the soil bacterial community to assess differences that can be reflected in the environmental and agricultural functionality, identifying possible bacterial species with ecological properties. In this context, the composition of bacterial communities (at the phyla, order, class, and species levels) was evaluated under different conditions, such as conventional tillage (CT) (plophing), reduced tillage (RT) (stubble cultivator), strip tillage (ST), and no-tillage (direct sowing on stubble and fallow buffer zone of the experimental field), in a horse bean plantation. Metagenomic methods (next generation sequencing technology, NGS) were used to determine the percentage of individual operational taxonomic units (OTUs). Our study showed that no-tillage cultivation technologies, mainly strip and no-tillage methods, had a positive effect on microbiological communities. In fact, key species related to soil fertility and crop yield, such as Gemmatimonas aurantiaca (a microorganism that reduce nitrous oxide, N2O in soil) and Aeromicrobium ponti (a beneficial species for the soil environment, essential for the proper functioning of the crop agroecosystem), increased in reduced cultivation technologies. These species can determine soil fertility and crop yields, and therefore, they are very important for sustainable and even regenerative agriculture. Further studies of soil samples collected from other crop plantations under different cropping systems may indicate beneficial microbial species that are important for soil fertility.
SposĂłb usuwania zanieczyszczeĆ ropopochodnych z gleby na drodze biodegradacji przy uĆŒyciu kwasĂłw humusowych i hydrolizatu droĆŒdĆŒowego
Temperature, Salinity and Garlic Additive Shape the Microbial Community during Traditional Beetroot Fermentation Process
Plant-based traditional fermented products are attracting a lot of interest in global markets. An example of them is beetroot leaven, which is valued for its high bioactive compound content. The variety of production recipes and the spontaneous nature of red beet fermentation favor its high diversity. This study aimed to analyze the impact of external factorsâtemperature, brine salinity, and garlic doseâon the beetroot fermentation and bacterial metapopulation responsible for this process. The research results confirmed the significant influence of the selected and analyzed factors in shaping the leaven physicochemical profile including organic acid profile and betalain content. Analysis of bacterial populations proved the crucial importance of the first 48 h of the fermentation process in establishing a stable metapopulation structure and confirmed that this is a targeted process driven by the effect of the analyzed factors. Lactobacillaceae, Enterobacteriaceae, and Leuconostocaceae were observed to be the core microbiome families of the fermented red beet. Regardless of the impact of the tested factors, the leaven maintained the status of a promising source of probiotic bacteria. The results of this research may be helpful in the development of the regional food sector and in improving the quality and safety of traditionally fermented products such as beetroot leaven.
Acetic and citric acids effect the type II secretion system and decrease the metabolic activities of salmon spoilage-related Rahnella aquatilis KM05
AbstractRahnella aquatilis causes seafoods to spoil by metabolizing sulfur-containing amino acids and/or proteins, producing H2S in products. The type II secretion system (T2SS) regulates the transport of proteases from the cytoplasm to the surrounding environment and promotes bacterial growth at low temperatures. To prevent premature fish spoilage, new solutions for inhibiting the T2SS of bacteria should be researched. In this study, global transcriptome sequencing was used to analyze the spoilage properties of R. aquatilis KM05. Two of the mapped genes/coding sequences (CDSs) were matched to the T2SS, namely, qspF and gspE, and four of the genes/CDSs, namely, ftsH, rseP, ptrA and pepN, were matched to metalloproteases or peptidases in R. aquatilis KM05. Subinhibitory concentrations of citric (18 ”M) and acetic (41 ”M) acids caused downregulation of T2SS-related genes (range from ââ1.0 to -4.5) and genes involved in the proteolytic activities of bacteria (range from ââ0.5 to -4.0). The proteolytic activities of R. aquatilis KM05 in vitro were reduced by an average of 40%. The in situ experiments showed the antimicrobial properties of citric and acetic acids against R. aquatilis KM05; the addition of an acidulant to salmon fillets limited microbial growth. Citric and acetic acids extend the shelf life of fish-based products and prevent food waste.
Effect of Processing Treatment and Modified Atmosphere Packing on Carrotâs Microbial Community Structure by Illumina MiSeq Sequencing
The aim of this study was to analyze the microbiome of carrot (Daucus carota subsp. sativus) subjected to minimal pre-treatment (rinsing in organic acid solution) and packaging in a high-oxygen modified atmosphere, and then stored for 17 days under refrigeration conditions (4 °C). The highest levels of bacteria in the carrot microbiome were characterized, at almost 78%, by bacteria belonging to the Enterobacteriaceae and Pseudomonadaceae families. Rinsing in a solution of ascorbic and citric acids resulted in the improvement of microbiological quality in the first day of storage. However, the use of a high-oxygen modified atmosphere extended the shelf life of the minimally processed product. Compared to carrots stored in air, those stored in high oxygen concentration were characterized by a greater ratio of bacteria belonging to the Serratia and Enterobacter genera, and a lower ratio belonging to the Pseudomonas and Pantoea genera. Moreover, the ÎČ-biodiversity analysis confirmed that the oxygen concentration was the main factor influencing the differentiation of the metabiomes of the stored carrots. The bacterial strains isolated from carrots identified by molecular methods were mostly pathogenic or potentially pathogenic microorganisms. Neither the minimal pre-treatment nor packaging in high-oxygen atmosphere was able to eliminate the threat of pathogenic bacteria emerging in the product.
Chlorogenic Acid Inhibits Rahnella aquatilis KM25 Growth and Proteolytic Activity in Fish-Based Products
This work verified the antiproliferative and antiproteolytic activities of chlorogenic acid against Rahnella aquatilis KM25, a spoilage organism of raw salmon stored at 4 °C. Chlorogenic acid limited the growth of R. aqatilis KM25 in vitro at a concentration of 2.0 mg/mL. The dead (46%), viable (25%), and injured (20%) cell subpopulations were identified by flow cytometry following treatment of R. aquatilis KM25 with the examined agent. The exposure of R. aquatilis KM25 to chlorogenic acid altered its morphology. Changes in cell dimensions, mostly in length parameters from 0.778 ”m to 1.09 ”m, were found. The length of untreated cells ranged from 0.958 ”m to 1.53 ”m. The RTâqPCR experiments revealed changes in the expression of genes responsible for the proliferation and proteolytic activity of cells. Chlorogenic acid caused a significant reduction in the mRNA levels of the ftsZ, ftsA, ftsN, tolB, and M4 genes (â2.5, â1.5, â2.0, â1.5, and â1.5, respectively). In situ experiments confirmed the potential of chlorogenic acid to limit bacterial growth. A similar effect was noted in samples treated with benzoic acid, where the growth inhibition of R. aquatilis KM25 was 85â95%. Reduction of microbial R. aquatilis KM25 proliferation significantly limited total volatile base nitrogen (TVB-N) and trimethylamine (TMA-N) formation during storage, extending the shelf life of model products. The TVB-N and TMA-N parameters did not exceed the upper levels of the maximum permissible limit of acceptability. In this work, the TVB-N and TMA-N parameters were 10â25 mg/100 g and 2.5â20.5 mg/100 g, respectively; for samples with benzoic acid-supplemented marinades, the parameters TVB-N and TMA-N were 7.5â25.0 mg/100 g and 2.0â20.0 mg/100 g, respectively. Based on the results of this work, it can be concluded that chlorogenic acid can increase the safety, shelf life, and quality of fishery products.
DoseâResponse Effect of Nitrogen on Microbial Community during Hydrocarbon Biodegradation in Simplified Model System
Knowledge about the influence of C:N ratio on the biodegradation process of hydrocarbon compounds is of significant importance in the development of biostimulation techniques. The purpose of this study was to assess the impact of nitrogen compounds on the environmental consortium during the process of biological decomposition of hydrocarbons. The experimental variants represented low, moderate, and excessive biostimulation with nitrogen compounds. The metabolic activity of the consortium was tested using the flow cytometry technique. The efficiency of the biodegradation of hydrocarbons of the consortium, based on the gas chromatography method, and metapopulation changes, based on the analysis of V4 16srRNA sequencing data, were assessed. The results of the research confirm the positive effect of properly optimized biostimulation with nitrogen compounds on the biological decomposition of polycyclic aromatic hydrocarbons. The negative impact of excessive biostimulation on the biodegradation efficiency and metabolic activity of microorganisms is also proven. Low resistance to changes in the supply of nitrogen compounds is demonstrated among the orders Xanthomonadales, Burkholderiales, Sphingomonadales, Flavobacteriales, and Sphingobacteriales. It is proven that quantitative analysis of the order of Rhizobiales, characterized by a high-predicted potential for the decomposition of polycyclic aromatic hydrocarbons, may be helpful during biostimulation optimization processes in areas with a high nitrogen deficiency.
Potassium Chloride, Sodium Lactate and Sodium Citrate Impaired the Antimicrobial Resistance and Virulence of Pseudomonas aeruginosa NT06 Isolated from Fish
Sodium chloride (NaCl) is a commonly used additive in minimally processed fish-based products. The addition of NaCl to fish products and packaging in a modified atmosphere is usually efficient with regard to limiting the occurrence of the aquatic environmental pathogen Pseudomonas aeruginosa. Given the negative effects of excess NaCl in the diet, there is a growing demand to reduce NaCl in food products with safer substituents, but the knowledge of their impact on antibiotic resistant P. aeruginosa is limited. This study aimed to evaluate the physiological and transcriptome characteristics of P. aeruginosa NT06 isolated from fish and to determine the effect of selected concentrations of alternative NaCl compounds (KCl/NaL/NaC) on the P. aeruginosa NT06 virulence phenotype and genotype. In the study, among the isolated microorganisms, P. aeruginosa NT06 showed the highest antibiotic resistance (to ampicillin, ceftriaxone, nalidixic acid, and norfloxacin) and the ability to grow at 4 °C. The Comprehensive Antibiotic Resistance Database (CARD) and the Virulence Factor Database (VFDB) revealed the presence of 24 and 134 gene products assigned to AMR and VF in the P. aeruginosa NT06 transcriptome, respectively. KCl, KCl/NaL and KCl/NaL/NaC inhibited pyocyanin biosynthesis, elastase activity, and protease activity from 40 to 77%. The above virulence phenotypic observations were confirmed via RTâqPCR analyses, which showed that all tested AMR and VF genes were the most downregulated due to KCl/NaL/NaC treatment. In conclusion, this study provides insight into the potential AMR and VF among foodborne P. aeruginosa and the possible impairment of those features by KCl, NaL, and NaC, which exert synergistic effects and can be used in minimally processed fish-based products.
The Influence of Bacteria Causing Subclinical Mastitis on the Structure of the Cowâs Milk Microbiome
Mastitis is the most expensive disease of dairy cattle across the world and is the main reason for the use of antibiotics in animal husbandry. The aim of this study was to analyze the microbiome of raw milk obtained from a semi-subsistence farm located in the KuyavianâPomeranian Voivodeship in Poland. Milk from healthy cows and from cows with subclinical mastitis was analyzed. The following pathogenic bacteria were found in milk from individuals with subclinical mastitis: Escherichia coli or Streptococcus agalactiae. The composition of drinking milk was assessed on the basis of 16S rRNA gene sequencing using the Ion Torrent platform. Based on the conducted research, significant changes in the composition of the milk microbiome were found depending on the physiological state of the cows. The microbiome of milk from healthy cows differed significantly from the milk from cows with subclinical mastitis. Two phyla dominated in the milk from healthy cows: Firmicutes and Proteobacteria, in equal amounts. On the contrary, in the milk from cows with diagnosed subclinical mastitis, one of the types dominated: either Firmicutes or Proteobacteria, and was largely predominant. Moreover, the milk microflora from the ill animals were characterized by lower values of the determined biodiversity indicators than the milk from healthy cows. The presence of pathogenic bacteria in the milk resulted in a significant reduction in the share of lactic acid bacteria in the structure of the population of microorganisms, which are of great importance in the production technology of regional products.
Gallic and ferulic acids suppress proteolytic activities and volatile trimethylamine production in the foodâborne spoiler Rahnella aquatilis KM05
AbstractBACKGROUNDRahnella aquatilis is a recognised microbial threat that alters the sensory properties of seafood. The high frequency with which R. aquatilis is isolated from fish has prompted a search for alternative preservatives. In the present study, in vitro and fishâbased ecosystem (raw salmonâbased medium) approaches were used to validate the antimicrobial effects of gallic (GA) and ferulic (FA) acids against R. aquatilis KM05. The results were compared with data describing the response of KM05 to sodium benzoate. Bioinformatics data of the whole genome were used to analyse the potential for fish spoilage by KM05 in detail, and the results revealed the main physiological characteristics that underlie reduced seafood quality.RESULTSIn the KM05 genome, the most abundantly enriched Gene Ontology terms were âmetabolic processâ, âorganic substance metabolic processâ and âcellular processâ. Through an evaluation of the Pfam annotations, 15 annotations were found to be directly involved in the proteolytic activity of KM05. Peptidase_M20 was the most abundantly represented (abundance value of 14060). Proteins representing the CutC family (abundance value of 427) indicated the potential for KM05 degradation of trimethylâamineâNâoxide. Subinhibitory concentrations of GA and FA suppressed the proteolytic activities of KM05 both in vitro and in RS medium by an average of 33â45%. These results were confirmed by quantitative realâtime PCR experiments, which also showed that the expression levels of genes involved in proteolytic activities and volatile trimethylamine production were also decreased.CONCLUSIONPhenolic compounds can be used as potential food additives for preventing quality deterioration of fish products. © 2023 Society of Chemical Industry.
SposĂłb biodegradacji zanieczyszczeĆ ropopochodnych z gleby wspomagany surfaktantami naturalnymi
Black pepper and tarragon essential oils suppress the lipolytic potential and the type II secretion system of P. psychrophila KM02
AbstractGiven the increasing consumer demand for raw, nonprocessed, safe, and long shelf-life fish and seafood products, research concerning the application of natural antimicrobials as alternatives to preservatives is of great interest. The aim of the following paper was to evaluate the effect of essential oils (EOs) from black pepper (BPEO) and tarragon (TEO), and their bioactive compounds: limonene (LIM), ÎČ-caryophyllene (CAR), methyl eugenol (ME), and ÎČ-phellandrene (PHE) on the lipolytic activity and type II secretion system (T2SS) of Pseudomonas psychrophila KM02 (KM02) fish isolates grown in vitro and in fish model conditions. Spectrophotometric analysis with the p-NPP reagent showed inhibition of lipolysis from 11 to 46%. These results were confirmed by RT-qPCR, as the expression levels of lipA, lipB, and genes encoding T2SS were also considerably decreased. The supplementation of marinade with BPEO and TEO contributed to KM02 growth inhibition during vacuum packaging of salmon fillets relative to control samples. Whole-genome sequencing (WGS) provided insight into the spoilage potential of KM02, proving its importance as a spoilage microorganism whose metabolic activity should be inhibited to maintain the quality and safety of fresh fish in the food market.
Ecological Engineering Using Biological Crusts: Effects on Soil Physicochemical Properties in West-Central Region of Burkina Faso
The land degradation in Burkina Faso is one of the major development challenges in the agricultural sector. Among the various existing means of soil recovery and improvement, the use of ecological engineering based on soils microorganisms also appears as a tool for sustainable land management. For this purpose, a trial was set up in PĂ©yiri in the West-Center region of Burkina Faso and focused on studying the effects of induced biological crusts on the physicochemical properties of degraded soils. A split-plot design with three replications was set up on three types of soil environment with increasing degradation level, namely "Soil environment with a dense herbaceous layer and some shrubs" (Site 3), "Soil environment with a less dense herbaceous layer" (Site 2) and "Bare soil environment" (Site 1). On each replication plot, three samples core were taken from the 0-20cm layer along the diagonal and were subjected to physicochemical analysis. The organic status (Total C, N and C/N ratio), physical properties (particle size distribution, texture, moisture content), chemical indexes (SĂ©ch, CEC, pH, V, Conductivity) and major nutrients (NO3-, NH4+, K+, Mg2+, Ca2+, Total P) were evaluated. The results obtained revealed that the treatment with the induced biocrust increased the rates of C, N, SĂ©ch, CEC, V, pH, NH4+, P and clay fraction, with much higher moisture. Taking into account the level of soil degradation, the balance on the site 1 presented the highest positive values in N, clay, pF4.5, Sech, CEC, pH, and P. On the site 2 and site 3, the results balance is sometimes positive or negative depending on the considered soil properties. Then the level of soil degradation influenced the biocrust efficiency, but in general the use of induced biocrust led to an improvement in the physicochemical properties of degraded soils especially on some major nutrients such as N and P. Soils in Burkina Faso like the others Sahelian countries are mostly deficient in these major nutrients. The induced biocrusts seem to be as a sustainable management tool for drylands agrosystems.
2,4-D versus 2,4-D based ionic liquids: Effect of cation on herbicide biodegradation, tfdA genes abundance and microbiome changes during soil bioaugmentation.
New potential biomarkers of ulcerative colitis and disease course â integrated metagenomic and metabolomic analysis among Polish patients
Abstract Background & aim The course of ulcerative colitis (UC) involves successive periods of remission and exacerbation but is difficult to predict. Gut dysbiosis in UC has already been intensively investigated. However, are periods of exacerbation and remission associated with specific disturbances in the composition of the intestinal microbiota and its metabolome? Our goal was to answer this question and to identify bacteria and metabolites necessary to maintain the remission. Methods We enrolled 65 individuals, including 20 UC patients in remission, 15 in exacerbation, and 30 healthy controls. Metagenomic profiling of the gut microbial composition was performed based on 16S rRNA V1-V9 sequencing. Stool and serum metabolic profiles were studied by chromatography combined with mass spectrometry. Results We revealed significant differences in the gut bacterial and metabolic composition between patients in active UC and those in remission, as well as in healthy controls. As associated with UC remission we have identified following bacteria: Akkermansia, Agathobacter, Anaerostipes, Enterorhabdus, Coprostanoligenes, Colinsella, Ruminococcus, Subdoligranulum, Lachnoclostridium, Coriobacteriales, Erysipelotrichaceae, and Family XII, and compounds â 1-hexadecanol, phytanic acid, squalene, adipic acid, cis-gondoic acid, nicotinic acid, tocopherol gamma, ergosterol and lithocholic acid. Whereas, in the serum lithocholic acid, indole and xanthine were found as potential candidates for biomarkers of UC remission. Conclusion We have demonstrated that specific bacteria, metabolites, and their correlations could be crucial in the remission of UC among Polish patients. Our results provide valuable insights and a significant source for developing new hypotheses on host-microbiome interactions in diagnosis and course of UC. Graphical abstract
Konsorcjum bakteryjno-grzybowe i sposĂłb bioremediacji gleby skaĆŒonej substancjami ropopochodnymi
Genome-Wide Association Study for Markers Related to Protein, Fiber (ADF and NDF) and Oil Content in Winter Oilseed Rape Seeds (Brassica napus L.)
Seed biochemical composition critically influences the quality and industrial value of oilseed rape (Brassica napus L.). Understanding the genetic basis of seed oil, protein, and fiber content is essential for breeding improved cultivars. Here we conducted a genome-wide association study (GWAS) on 350 diverse winter oilseed rape lines over three years, using near-infrared reflectance spectroscopy (NIRS) to measure seed traits and SNP genotyping for association mapping. We identified numerous SNP markers significantly associated with seed oil, protein, acid detergent fiber (ADF), and neutral detergent fiber (NDF) content. From 18,566 detected SNPs, 3782 met stringent criteria and were used for association mapping, resulting in 3189 significant associations across three years. The highest number of associations was observed for protein (3480), followed by NDF (3662), ADF (3422), and oil (2046). Individual markers explained up to 35% of phenotypic variation, indicating strong genetic control of these traits. Gene ontology enrichment analyses linked candidate genes to key metabolic and regulatory pathways influencing these traits: protein biosynthesis and post-translational modification, lipid metabolism regulated by phosphorylation, and transcriptional control of cell wall polysaccharide synthesis. These findings provide valuable molecular markers that can be validated for further use in marker-assisted selection, supporting the development of rapeseed cultivars with optimized seed quality for food, feed, and industrial applications.
Identification of SSR Markers Associated with Yield-Related Traits and Heterosis Effect in Winter Oilseed Rape (Brassica Napus L.)
The identification of markers responsible for regulating important agronomic traits in rapeseed supports breeding and increases the seed yield. Microsatellite (SSR) markers are mainly used as âneutralâ genetic markers but are also linked with many biological functions. The objective of this study was identification of microsatellite markers associated with important agronomic traits affecting the seed yield of winter oilseed rape and with the heterosis effect for these traits. The plant material consists of four parental lines, 60 doubled haploid (DH) lines, 60 single cross hybrids, and 60 three-way cross hybrids. The association between molecular markers and observed traits was estimated using regression analysis. Among 89 SSR markers, 43 were polymorphic, and 15 were selected for mapping because they demonstrated stability in both years of observation. These markers were physically mapped in the rapeseed reference genomes and their immediate vicinity was searched to identify candidate genes associated with the studied traits. Six markers (BrGMS3837, BnEMS1119, BrGMS2901, BnGMS0509, BrGMS3688, BrGMS4057), which showed a positive estimation effect in our association analysis, and thus increased the value of a given trait or heterosis effect, turned out to be linked with genes that could be responsible for the development and growth of plants.
