Enriched Medium Research Articles

Fungal species inhabiting calcareous soil in western Maharashtra, India, and their role in the release of soil-bonded Fe and Zn micronutrients for crop plant availability in such soils

Calcareous soils which are around 30 per cent of the world over are unproductive for agricultural crop cultivation and productivity. In calcareous soils, most of the plant nutrients and micronutrients are not freely available to the crop plants as these often lie in fixed or bonded form. Therefore, these nutrients have to be released from their bonded form to freely available form in such soils to make them available for crop plant growth. The application of microbial species native to such calcareous soils and having the ability and capacity to release such bonded nutrients is a need of the day to convert these unproductive soils into productive ones. The microbial species that work as nutrient/micronutrient-salt solubilizing agents generally form a salt solubilization zone around the microbial colony while salt-mobilizing /salt-releasing microbes do not form such a solubilization zone around the microbial colonies. In the present investigation, we studied the presence of microbial flora particularly the fungal species in the calcareous soil in western Maharashtra, India, and their role in the release of the bonded Fe and Zn micronutrients from the calcareous soil to make them available for the kidney-bean plant growth grown in such soil. Six fungal cultures of distinct colony morphology were isolated from the calcareous soil as the calcareous soil- inhabiting fungal species, on a specialized enriched media. They did not form the solubilization zone on the Fe and Zn enriched media and therefore were considered and tested for their efficacy as Fe and Zn salt-releasing/demineralizing microbes. The release for Fe and Zn from their fixed form was 1.68 and 1.91µg/g of calcareous soil respectively by these demineralizing fungal bio-inoculants. The release of Fe and Zn in calcareous soil was found to play a role in the growth and yield-attributing parameters of kidney-bean plants in calcareous soil. These fungal cultures were identified as species of Glomus, Mucor, and Aspergillus. Therefore, these calcareous soils inhabiting fungal species having demineralization activity can be applied as demineralizing bio-inoculants to the calcareous soil regularly to make them crop productive, and for their reclamation.

Discovery of Novel Stimulators of Pax7 and/or MyoD: Enhancing the Efficacy of Cultured Meat Production through Culture Media Enrichment.

The principles of myogenesis play crucial roles in the production of cultured meat, and identifying protein stimulators associated with myogenesis holds great potential to enhance the efficiency of this process. In this study, we used surface plasmon resonance (SPR)-based screening of a natural product library to discover ligands for Pax7 and MyoD, key regulators of satellite cells (SCs), and performed cell-based assays on Hanwoo SCs (HWSCs) to identify substances that promote cell proliferation and/or differentiation. Through an SPR analysis, we found that six chemicals, including one Pax7+/MyoD- chemical, four Pax7+/MyoD+ chemicals, and one Pax7-/MyoD+ chemical, bound to Pax7 and/or MyoD proteins. Among four Pax7+/MyoD+ chemicals, parthenolide (0.5 and 1 µM) and rutin (100 and 200 µM) stimulated cell proliferation in the medium with 10% FBS similar to the medium with 20% FBS, without affecting differentiation. Adenosine, a Pax7-/MyoD+ chemical, accelerated differentiation. These chemicals could be potential additives to reduce the reliance of FBS required for HWSC proliferation and differentiation in cultured meat production.

Optically thick structure in early B-type supergiant stellar winds at low metallicities

ABSTRACT Accurate determination of mass-loss rates from massive stars is important to understand stellar and galactic evolution and enrichment of the interstellar medium. Large-scale structure and variability in stellar winds have significant effects on mass-loss rates. Time-series observations provide direct quantification of such variability. Observations of this nature are available for some Galactic early supergiant stars but not yet for stars in lower metallicity environments such as the Magellanic Clouds. We utilize ultraviolet spectra from the Hubble Space Telescope ULLYSES program to demonstrate that the presence of structure in stellar winds of supergiant stars at low metallicities may be discerned from single-epoch spectra. We find evidence that, for given stellar luminosities and mean stellar wind optical depths, structure is more prevalent at higher metallicities. We confirm, at Large Magellanic Cloud (0.5 Z⊙), Small Magellanic Cloud (0.2 Z⊙), and lower (0.14–0.1 Z⊙) metallicities, earlier Galactic results that there does not appear to be correlation between the degree of structure in stellar winds of massive stars and stellar effective temperature. Similar lack of correlation is found with regard to terminal velocity of stellar winds. Additional and revised values for radial velocities of stars and terminal velocities of stellar winds are presented. Direct evidence of temporal variability, on time-scales of several days, in stellar wind at low metallicity is found. We illustrate that narrow absorption components in wind-formed profiles of Galactic OB stellar spectra remain common in early B supergiant spectra at low metallicities, providing means for better constraining hot, massive star mass-loss rates.

General media over enrichment media supports growth of Campylobacter jejuni and maintains poultry cecal microbiota enabling translatable in vitro microbial interaction experiments.

This study aimed to assess the suitability of two media types, Bolton enrichment broth (BEB) and anaerobic dilution solution (ADS), in replicating the poultry cecal environment to investigate metabolic interactions and Campylobacter presence within poultry ceca. Using an anaerobic in vitro poultry cecal model, cecal contents (free of culturable Campylobacter) were diluted in BEB and ADS, inoculated with 105 CFU of Campylobacter jejuni, and incubated for 48 h at 42°C under microaerophilic conditions. Samples were collected at 0, 24, and 48h. Genomic DNA was extracted, amplified, and sequenced on Illumina MiSeq platform. Data underwent analysis within QIIME2-2021.11, including alpha and beta diversity assessments, ANOVA, ADONIS, ANCOM, and Bradford assay for protein concentration. ADS supported a more diverse microbial population than BEB, influencing C. jejuni presence. ANCOM highlighted dominant genera in BEB (Lactobacillus and Campylobacter) and affirmed C. jejuni growth in ADS. Core microbiota analysis revealed unique associations with each media type, while the Bradford assay indicated ADS consistently yielded more uniform microbial growth. ADS was identified as a preferred diluent for faithfully replicating cecal microbial changes in the presence of Campylobacter.

Development and early testing of a simple, low cost, fast sensor for maternal and neonatal group B Streptococcus

Streptococcus agalactiae, (Group B Streptococcus (GBS)), is a common colonizer of the female vagina. In women giving birth it can be transmitted to the baby and cause serious illness and even death to the child. We have developed a biosensor comprising of phospholipids and fatty acids vesicles encapsulating high concentration, self-quenched carboxyfluorescein, which is released by the lysis of the vesicle by virulence factors expressed by GBS, becoming diluted and fluorescent. The microbial specificity of the sensor was tested against a number of GBS strains and other microbes including Candida albicans, Enterococcus faecalis and Staphylococcus epidermidis and a statistically significant response to GBS measured over these other microbes. To test the invivo efficacy of the biosensor, a pilot study using donated lower vaginal swabs from non-pregnant women was conducted, where 58 female adults were recruited. Participants donated two swabs, one which was used for the vesicle test and one for the ‘gold standard’, enriched culture media (ECM) test. An overall GBS carriage rate of 17.2% was measured using the ECM test. The vesicle biosensor test took 45 min to obtain a result, and showed a sensitivity of 83.3%, specificity of 85.7% and accuracy of 85.3%. The test accuracy is in line with current novel GBS identification tests, with the advantage of being rapid, easy to use, low-cost and able to be conducted by bedside during start of labour.

Effects of using collagen and aloe vera grafted fibroin scaffolds on osteogenic differentiation of rat bone marrow mesenchymal stem cells in SBF-enriched cell culture medium

In the study, collagen and aloe vera were grafted onto silk fibroin with two different methods, and 3D-microporous scaffolds (1F5C4A1 and 2F5C4A1) were formed by lyophilization. Three osteogenic cultures were started by seeding rat bone marrow mesenchymal stem cells (MSCs) and pre-induced MSC (osteoblast (OB)) on biopolymeric scaffolds. The osteogenic medium was enriched with 10% (v/v) simulated body fluid (SBF) to promote mineralization and osteogenic differentiation in one of the MSC cultures and the OB culture. X-ray diffraction (XRD), scanning electron microscopy (SEM), scanning electron microscopy- energy dispersive spectrum (SEM-EDS) analyses on cellular samples and histochemical (alizarin red, safranin-O, alcian blue) and immunohistochemical (anti-collagen-1, anti-osteocalcin, anti-osteopontin) staining showed that bone-like mineralization was occurred by both chemically and cellular activity. In addition, pre-osteogenic induction of MSCs in 2D-cultured was found to promote osteogenesis more rapidly when started 3D-cultured. These results indicated that enrichment of the cell culture medium with SBF is sufficient for in vitro mineralization rather than using high concentrations of SBF. The findings showed that OB cells on the 2F5C4A1 scaffold obtained the best osteogenic activity. Still, other culture media with 10% SBF content could be used for bone tissue engineering under osteogenic induction.

Functional characterisation of Euglena gracilis following growth medium enrichment

In recent years, microalgae, particularly Euglena gracilis, have been candidates for the food/feed industry thanks to their nutritional and functional properties. However, the inclusion of E. gracilis in the diet of livestock animals is little studied, especially regarding its antioxidant activity. Furthermore, microalgae are known for their variability in nutritional quality and functional properties, mainly due to cultivation conditions. For this reason, the aim of the present work was to investigate the nutritional and functional aspects (total phenolic content TPC, Folin-Ciocalteu assay); antioxidant activity (ABTS and FRAP assays) of E. gracilis, grown in three different media, following chemical extraction (H2O:EtOH) and ex vivo digestion method. The microalgae growth media were characterised as follows: EgM (standard medium); ETX (standard medium + aminoacidic-extract); DOE-ETX (ETX + microelements). The results showed an interesting nutritional profile for all the microalgae analysed, although the values were modulated by media nutrients. Although EgM (6.94 ± 0.25 g/L) was characterised by a significant higher growth yield than ETX (5.75 ± 0.14 g/L) and DOE-ETX (4.72 ± 0.17 g/L), results also confirmed by the paramylon content (4.35 ± 0.13; 3.16 ± 0.08; 2.25 ± 0.05 g/L, respectively) (p < 0.05), it did not show a high functional profile. More specifically, DOE-ETX showed higher values for TPC, ABTS, and FRAP, following chemical extraction, in particular 50 and 75% EtOH and ex vivo digestion. These results confirmed the potential of E. gracilis as a valuable source of functional feed ingredients. Further investigations will be crucial to optimise the formulation of the culture medium to obtain a high yield of algae with improved functional characteristics.HIGHLIGHTSConstant population growth has prompted scientific research to investigate new protein alternatives. Euglena gracilis represents a valid candidate.The type of growth medium influences the nutritional and functional profile (total phenolic content and antioxidant activity) of E. gracilis.The addition of microelements to the E. gracilis medium resulted in a higher phenolic content and more marked antioxidant activity.

Optimizing Conditions for the Production of Bacterial Extracellular Vesicles of Vibrio vulnificus and Analysis of the Inner Small RNA Compositions.

Chemical and physical elements affecting the production of bacterial extracellular vesicles (BEVs) of the human pathogen Vibrio vulnificus were quantitatively assessed to optimize the conditions for the BEV production by using the western blot quantification for an outer membrane porin OmpU and by fluorescent dye FM4-64. When cells were cultured at 37°C in an enriched medium (2 × Luria Bertani; 2 × LB) in the presence of EDTA, they produced about 70% more BEVs. BEVs were purified from the cells cultured in the established optimal conditions by the density gradient ultracentrifugation. The dynamic light scattering measurement of the purified BEVs showed that the diameter of them ranged from approximately 25 nm to 161 nm. We hypothesized that there may be some features in nucleotide sequences specific to RNAs packaged in BEVs compared to those in cellular RNA molecules. We compared the nucleotide sequences and abundance of sRNAs between in the cellular fraction and in BEVs through next-generation sequencing (NGS). While no distinct feature was observed in the nucleotide sequences of sRNAs between two groups, the length of sRNA fragments from BEVs were significantly shorter than those in cytoplasm.

Enrichment-Sensing All-in-One Strategy Integrated in the La(OH)3-Au@AgNPs Substrate for Rapid Surface-Enhanced Raman Spectroscopy Analysis of Purine Components.

Improving the speediness of complex sample analysis has attracted much research interest in analytical science. In this work, an enrichment-sensing all-in-one strategy was presented for rapid surface-enhanced Raman spectroscopy (SERS) analysis of purine components by using the La(OH)3-Au@AgNPs nanocomposite. Two-dimensional (2D) La(OH)3 nanosheets with nanothickness and accessible active sites not only acted as efficient media for the rapid enrichment of analytes but also provided flat planes for the intensive decoration of Au@AgNPs nanoparticles to amplify the SERS signals of adsorbed analytes. The nanocomposite could realize the rapid enrichment-sensing of purine components in 1 min, including mercaptopurine, thioguanine, adenine, and purine. Subsequently, the surface adsorption behaviors were explored by density functional theory and the enhancement mechanisms were simulated by the finite-difference time-domain method. Moreover, the nanocomposite also exhibited good SERS performances with relative standard deviations (RSDs) of uniformity less than 6.5% (n = 23), RSDs of batch-to-batch stability less than 7.3% (n = 9), and long-term stability over 9 weeks with RSDs within 6.6%. Finally, the enrichment-sensing strategy was applied for the rapid SERS analysis of two projects: mercaptopurine in tablets and adenine in beers with detection limits of 6.0 and 0.76 μg/L and spiked recoveries of 90.9-100 and 84.2-101%, respectively. Benefiting from the high-performance enrichment medium and closely packed plasmonic nanoparticles, the enrichment-sensing all-in-one strategy possesses great potential for rapid on-site detection in food safety and pharmaceutical analysis.

Designing sustainable circular bioeconomy solutions for the pulse industry: The case of crude pea starch as a substrate for single cell protein production

Valorization of crude pea starch has become a key focus in the pea industry's sustainability pursuit. This study aimed to explore the circularity potential of crude pea starch as a nutrient-dense substrate for the solid-state cultivation of yeast (Saccharomyces cerevisiae) Single Cell Protein (SCP). Following the ISO 2006:14040/44 standard, a life cycle assessment (LCA) was performed to ascertain the environmental performance and operational dynamics of baseline and scenario pea starch-based yeast SCP process designs and identify optimal design considerations. Results demonstrated a higher relative contribution to the toxicity categories, with a relatively less contribution to global warming and land use. The distribution and media enrichment processes were identified as the hotspots, contributing about 32–55 % and 40–56 % to global warming and land use, respectively. Generally, train and air freight were more sustainable than lorry freight, respective of mileage and mass. Regarding system alteration, eliminating the media enrichment process could offset about 26 % of land footprint, with a similar trend for most impact categories. Process benchmarking showed up to a 3-fold reduction in global warming impacts relative to soybean meal, and about 71 % offset relative to fishmeal. Consequential LCA showed a general sustainability preference for substituting the aquacultural feeds with pea starch-based SCP, with a stronger emphasis on fishmeal substitution. Overall, these findings highlight the potential of the proposed SCP design as a sustainable upcycling solution with substitutionary potentials for conventional food and feeds, recommending further exploration in value and wealth creation.

The microalgae’s ability to accumulate selected trace elements studied by ICP-MS/MS and chemometric methods

BackgroundMicroalgae can be used in different branches of industry, including cosmetology, pharmaceutics and the food industry, information on their ability to accumulate different elements becomes more important. The microalgae biomass grown in the media enriched in elements can increase the accumulation of different ions and give a possibility to control the contents of the various elements. MethodsThe aim of the study was to determine the total content of metals in microalgae by tandem mass spectrometry with inductively coupled plasma (ICP-MS/MS) and analysis of the contents of particular metals as a function of the type of microalgae and conditions of cultivation. As the adverse effects of metals on the health of humans and animals have been well-documented and the use of microalgae has increased, the knowledge of metal contents in them is of particular importance in control of their quality. ResultsAnalysis of results permitted distinction of three main groups of microalgae with similar total metal content levels. Moreover, the results revealed the ways of stimulating more significant accumulation of selected elements (for example, Se concentration in control algae 0.279 µg g−1, in the algae cultivated in enriched medium – 219.7 µg g−1). They indicated the possible correlations between the accumulation of different ions. The result obtained shows a significant effect of metal accumulation and has a considerable impact on the differentiation of Arthrospira platensis grown in the medium enriched in different elements (selenium, zinc, chromium) (p ≤ 0.05). ConclusionsParticular impact on the content of selected elements had the conditions of cultivation (type of support) and the microalgae species. Although the one species as the most significant source of selected elements cannot be indicated, it is possible to control the accumulation by the composition of the medium.

Antibiotic-Resistant Arcobacter spp. in commercial and smallholder farm animals in Asante Akim North Municipality, Ghana and Korogwe Town Council, Tanzania: a cross-sectional study

BackgroundArcobacter species are considered emerging foodborne pathogens that can potentially cause serious infections in animals and humans. This cross-sectional study determined the frequency of potentially pathogenic Arcobacter spp. in both commercial and smallholder farm animals in Ghana and Tanzania. A total of 1585 and 1047 (poultry and livestock) samples were collected in Ghana and Tanzania, respectively. Selective enrichment media, along with oxidase and Gram testing, were employed for isolation of suspected Arcobacter spp. and confirmation was done using MALDI-TOF MS. Antibiotic susceptibility was assessed through disk diffusion method and ECOFFs were generated, for interpretation, based on resulting inhibition zone diameters.ResultsThe overall Arcobacter frequency was higher in Ghana (7.0%, n = 111) than in Tanzania (2.0%, n = 21). The frequency of Arcobacter in commercial farms in Ghana was 10.3% (n/N = 83/805), while in Tanzania, it was 2.8% (n/N = 12/430). Arcobacter was detected in only 3.6% (n/N = 28/780) of the samples from smallholder farms in Ghana and 1.5% (n/N = 9/617) of the samples from Tanzania. For commercial farms, in Ghana, the presence of Arcobacter was more abundant in pigs (45.1%, n/N = 37/82), followed by ducks (38.5%, n/N = 10/26) and quails (35.7%, n/N = 10/28). According to MALDI-TOF-based species identification, Arcobacter butzleri (91.6%, n/N = 121/132), Arcobacter lanthieri (6.1%, n/N = 8/132), and Arcobacter cryaerophilus (2.3%, n/N = 3/132) were the only three Arcobacter species detected at both study sites. Almost all of the Arcobacter from Ghana (98.2%, n/N = 109/111) were isolated during the rainy season. The inhibition zone diameters recorded for penicillin, ampicillin, and chloramphenicol allowed no determination of an epidemiological cut-off value. However, the results indicated a general resistance to these three antimicrobials. Multidrug resistance was noted in 57.1% (n/N = 12/21) of the Arcobacter isolates from Tanzania and 45.0% (n/N = 50/111) of those from Ghana. The type of farm (commercial or smallholder) and source of the sample (poultry or livestock) were found to be associated with multi-drug resistance.ConclusionsThe high levels of MDR Arcobacter detected from farms in both countries call for urgent attention and comprehensive strategies to mitigate the spread of antimicrobial resistance in these pathogens.

Geochemical and Environmental Evaluation of the Copper Element in the Surface Soil and Its Health Effects in Selected Areas of Kirkuk Governorate

To assess the extent of copper contamination in the surface soil and its effects on human health in selected areas of Kirkuk Governorate, several geochemical analyzes and environmental assessments were performed. Twenty-two (22) surface soil samples were collected and analyzed using an inductively coupled plasma mass spectrometer. The results showed that the average concentration of copper in the study area was (42.64 ppm), and its highest value was in the (H19) site represented in the Benji Ali area (129.7 ppm). In (H11) site, with a concentration of (88.8 ppm), which represents an industrial neighborhood area, and the reason is due to it being a polluted industrial area, which is higher than the permissible natural values, amounting to (20 ppm). In the soil, the element copper, which indicates a potential danger to the environment, as well as the average values of the soil accumulation index showed that it is unpolluted to medium pollution, while the value of the average enrichment factor was medium enrichment, and also the average of the environmental hazard index showed potential moderate environmental risks, and it was found Exposure through inhalation (CDIinh) is more effective in adults and children with copper than through skin contact (CDIdermal) and ingestion (CDIing). And it was found that the values (HI) are greater than one for the studied copper element for both children and adults, which indicates The presence of carcinogenic health risks of the copper element on humans in the study area, and it was found that children are particularly vulnerable to the effects of copper because they are still developing.

Growth assessment of Salmonella enterica multi-serovar populations in poultry rinsates with commonly used enrichment and plating media

Isolation of Salmonella from enrichment cultures of food or environmental samples is a complicated process. Numerous factors including fitness in various selective enrichment media, relative starting concentrations in pre-enrichment, and competition among multi-serovar populations and associated natural microflora, come together to determine which serovars are identified from a given sample. A recently developed approach for assessing the relative abundance (RA) of multi-serovar Salmonella populations (CRISPR-SeroSeq or Deep Serotyping, DST) is providing new insight into how these factors impact the serovars observed, especially when different selective enrichment methods are used to identify Salmonella from a primary enrichment sample. To illustrate this, we examined Salmonella-positive poultry pre-enrichment samples through the selective enrichment process in Tetrathionate (TT) and Rappaport Vassiliadis (RVS) broths and assessed recovery of serovars with each medium. We observed the RA of serovars detected post selective enrichment varied depending on the medium used, initial concentration, and competitive fitness factors, all which could result in minority serovars in pre-enrichment becoming dominant serovars post selective enrichment. The data presented provide a greater understanding of culture biases and lays the groundwork for investigations into robust enrichment and plating media combinations for detecting Salmonella serovars of greater concern for human health.

Two-Omics Probe on the Potential of Pseudomonas sp. GDMCC 1.1703 Under Phenol Stress.

Pseudomonas sp. harbors genetic diversity and readily adapts to environmental challenges, conferring upon it the ability to remediate. It is important to genetically determine the effects of bacterial application. The two-omics integration approach may shed more light on Pseudomonas isolates, filling the knowledge gap between genetic potential and dynamic function. In the present study, a strain from the Xi River was isolated using benzene-selective enrichment medium and phylogenetically identified as Pseudomonas sp. GDMCC 1.1703 by 16S rRNA gene sequencing. Its phenol degradability was optimally assessed at a rate of 45.7% (by statistics P < 0.05) in 12 h with a 200 mg/L concentration. Genomics and transcriptomics analyses were successively used to identify the genes and pathways responsible for phenol degradation. At least 42 genes were genomically identified to be involved in xenobiotic biodegradation. The degradative genes clustered into operons were hypothesized to have evolved through horizontal gene transfer. On the basis of genomic authentication, transcriptome analysis dynamically revealed that phenol degradation and responsive mechanisms were both upregulated as defense between the Ctrl (control) and PS (phenol-stressed) groups. Quantitative reverse transcription-PCR not only validated the key genes identified via RNA sequencing but also consistently confirmed the realistic intracellular expression. The approach of omics integration, which is effective in exploring the potential of isolates, will hopefully become an established method for determining the remediation potential of a candidate for development.

Analysis of virulence genes sequencing of Serratia marcescens in iraqi hospitals.

Analysis of virulence genes (PhlA, ShlA, FlhD) sequencing of Serratia marcescens including collection of two hundred twenty samples from sputum & wound infection of the period from April-June in 2021 of the patients in some hospitals in Baghdad - Iraq. These specimens were collected from central hospitals in Iraq. After laboratory diagnosis of these specimens by detecting morphological and biochemical tests on bacteria that were cultured on selective and enriched media, VITEK- 2 compact system. There are 40 bacterial isolates of Serratia marcescens from total samples (220) in percentage (18.18%). The genome of these bacteria was extracted to investigate target virulence genes that were amplified by specific forward and specific primers. The product size of virulence genes was Ph1A (207 bp), Sh1A (217 bp), and FlhD virulence gene (307 bp). The results exhibited that these isolates contained these genes at different levels. Sequencing of these genes was carried out and analyzed through BLAST in NCBI and Geneious version -9. The results explained the top identity of sequencing these virulence genes (PhlA, ShlA, FlhD) between local Iraqi bacteria. In addition, there are misidentify or dissimilarities in different levels between Iraqi S. marcescens and global strain recorded in NCBI. These results consider scientific evidence to find new variations of these virulence genes in Iraqi S. marcescens in comparison with the global strain. These new Iraqi bacterial variation sequencing registered in the global database in NCBI under accession numbers including (Ph1A virulence gene LC647828.1 & LC647829.1), (Sh1A virulence gene LC647830.1 & LC647831.1) & (F1hD virulence gene LC647826.1, LC647827.1). The results of analysis sequencing exhibited different percentages in genetic identity distance, which refer to these bacteria new variation in Pathogenicity Island. These results explained the ability of these bacteria to produce different levels of virulence factors that lead to an increase in pathogenicity and spreading of infection.

PSXIV-27 Liver Abscesses in Feedlot Cattle: Further Studies on Etiology and Pathogenesis Liver Abscesses in Feedlot Cattle: Further Studies on Etiology and Pathogenesis

Abstract Liver abscesses (LA) are a polymicrobial infection and the causative agents include two subspecies of Fusobacterium necrophorum, necrophorum and funduliforme, and Trueperella pyogenes. Nucleic acid-based analysis of the purulent material of LA has indicated that Proteobacteria and Bacteroidetes were the dominant phyla, next to phylum Fusobacteria. The sporadic isolations of bacterial species of the Proteobacteria and Bacteroidetes in LA have been reported. An aspect of the pathogenesis that has not been investigated is whether bacterial pathogens in LA originate, besides the rumen, from the colon? Therefore, our objectives were to target detection and isolations of Salmonella enterica, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Bacteroides fragilis, in addition to routine isolations of F. necrophorum and T. pyogenes, from LA and also from ruminal and colonic epithelial tissues of the same animals. Liver abscesses, matched with ruminal and colonic epithelial tissue samples from 96 steers and heifers, originating from 15 feedlots, were collected at slaughter, transported to the laboratory and processed within 24 hours. Samples were subjected to anaerobic and aerobic culture methods, including enrichment and selective media for detection and isolation of S. enterica, E. coli, K. pneumonia, P. aeruginosa, and B. fragilis. Prevalence of bacterial species were shown in table 1. For each bacterium, two-sided Fisher's exact test was used to evaluate the association of its prevalence in LA with that in colon and rumen at 0.05 level. Overall, prevalence of subsp. necrophorum, subsp. funduliforme, T. pyogenes and S. enterica in liver abscesses were 86.4% (83/96), 21.8% (21/96), 35.4% (34/96) and 6.2% (6/96), respectively (Table 1). In ruminal tissue samples, prevalence of subsp. necrophorum, subsp. funduliforme, T. pyogenes and S. enterica were 6.6% (6/96), 40.6% (39/96), 11.4% (11/96) and 4.1% (4/96), respectively. Prevalence of subsp. necrophorum, subsp. funduliforme, T. pyogenes and S. enterica in colonic tissues were 18.7% (18/96), 36.4% (35/96), 0% (0/96) and 7.2% (7/96), respectively. Prevalence of E. coli, Klebsiella spp., and P. aeruginosa in LA samples were 70.8% (68/96), 92.7% (89/96), and 91.6% (88/96), respectively. Prevalence of E. coli, Klebsiella spp., and P. aeruginosa in rumen epithelial tissue samples were 17.7% (17/96), 50.0%, (48/96), and 15.6% (15/96), respectively. Prevalence of E. coli, Klebsiella spp., and P. aeruginosa in colonic tissue samples were 16.6% (16/96), 24.0% (26/96), and 12.5% (12/96), respectively. Prevalence of subsp. funduliforme in ruminal and colonic tissues was greater than subsp. necrophorum. None of the liver abscess samples yielded B. fragilis. In conclusion, E. coli was the second most dominant species detected and isolated from LA, next only to subsp. necrophorum. The greater frequencies of isolations of subsp. necrophorum and S. enterica from colonic epithelial than ruminal epithelial tissues suggest that hindgut could also be a source of pathogens involved in LA.

Degradation of 17 α-ethynyl estradiol by Pseudomonas citronelolis BHUWW1 and its degradation pathway

17 α-ethynylestradiol (EE2) is the main component of birth control medications and is in huge demand worldwide. A major part of this hormone is excreted in the environment, where it acts as Endocrine Disrupting Compound (EDC). Thus, the removal of this hormone from the environment is essential. In this study, a bacterial strain identified as Pseudomonas citronelolis BHUWW1 was isolated from sewage-contaminated water of the Assi River by using enrichment in minimal medium supplemented with EE2 as a sole source of carbon. The strain was able to metabolize 94% of 10 mg/L of EE2 after eight days of incubation. Supplementation of co-carbon sources showed a positive impact on EE2 degradation. It was observed that supplementation with sodium acetate, sucrose, and glucose increased the efficiency of EE2 degradation. In the presence of metal ions, a decrease in EE2 degradation was observed. However, the strain BHUWW1 was able to degrade EE2 in the presence of tested metal ions. The metabolites arising after degradation of EE2 were identified by GC MS and a possible pathway of degradation was elucidated. It was observed that EE2 was first converted to estrone and then to 17 β-estradiol (E2). E2 was then hydroxylated, which led to an opening of the ring structure and its subsequent degradation. A few metabolites such as methyl succinic acid, ethyl malonic acid, and 4- hydroxyl butanoic acid formed during the degradation were also identified. The results of this study clearly demonstrate the role of strain BHUWW1 in the remediation of this hormone.

JWST's TEMPLATES for Star Formation: The First Resolved Gas-phase Metallicity Maps of Dust-obscured Star-forming Galaxies at z ∼ 4

We present the first spatially resolved maps of gas-phase metallicity for two dust-obscured star-forming galaxies at z ∼ 4, from the JWST TEMPLATES Early Release Science program, derived from NIRSpec integral field unit spectroscopy of the Hα and [N ii] emission lines. Empirical optical line calibrations are used to determine that the sources are globally enriched to near-solar levels. While one source shows elevated [N ii]/Hα ratios and broad Hα emission consistent with the presence of an active galactic nucleus in a ≳1 kpc region, we argue that both systems have already undergone significant metal enrichment as a result of their extremely high star formation rates. Utilizing Atacama Large Millimeter/submillimeter Array rest-frame 380 μm continuum and [Ci](3P2–3P1) line maps we compare the spatial variation of the metallicity and gas-to-dust ratio in the two galaxies, finding the two properties to be anticorrelated on highly resolved spatial scales, consistent with various literature studies of z ∼ 0 galaxies. The data are indicative of the enormous potential of JWST to probe the enrichment of the interstellar medium on ∼kpc scales in extremely dust-obscured systems at z ∼ 4 and beyond.

The potential of modified karst water as a substitute for microalgae culture media

Karst water concocted culture medium which contains high concentration of complex minerals was presumed to support production of microalgae, such as Spirulina sp. (Arthrospira sp.), Chlorella sp., and Nannochloropsis sp. This study aims to evaluate the potential of enriched karst water medium to grow Spirulina sp., Chlorella sp., and Nannochloropsis sp. There were two batches of culture with different treatments of nutrient supplementary; the first was for Spirulina sp. and the second was for Chlorella sp. and Nannochloropsis sp. The results showed that all treatments were suitable for Spirulina sp. with different growth rates. The medium with 20:1 N/P ratio showed the best productivity for Chlorella sp., and 10:1 N/P ratio for Nannochloropsis sp. The pure karst water and all level as the nutrient modified karst water media showed a relatively similar growth rate of Spirulina sp. Furthermore, in the best medium for Chlorella sp. and Nannochloropsis sp. gave increasing density until the end of observation, instead of a death phase of commercial addition batch culture. Generally, modified karst water has the potential to be used as the microalgae growing medium.