Microbial Content Research Articles

Efficacy of supplementing Aspergillus awamori in enhancing growth performance, gut microbiota, digestibility, immunity, and antioxidant activity of heat-stressed broiler chickens fed diets containing olive pulp

BackgroundGut microbes play a significant role in digestion, developing immunity, and intestinal health. Therefore, direct-fed microbials are used to modify gut microbiota, maintain a healthy digestive system, enhance immunity, and promote the broilers’ performance. In addition, it has a role in improving the utilization of unconventional feed ingredients (olive pulp, OP). This study provides the potential role of Aspergillus awamori in enhancing gut microbial content, nutrient utilization, growth performance, and antioxidative status in heat-stressed broiler chickens fed diets containing olive pulp.MethodsThree hundred chicks (Ross 308; one day old) were divided into four treatment groups (75 chick/ group) randomly, as follows; CON: chicks fed a basal diet based on corn and soybean meal, OP10: chicks fed a diet containing 10% OP, OA1: chicks fed a diet containing OP with A. awamori at 100 mg per kg, OA2: chicks fed a diet containing OP with A. awamori at 200 mg per kg.ResultsAdding A. awamori to the broiler diet that contains OP had a positive effect on productive performance via enhancing nutrition digestibility, body weight gain, feed conversion ratio, and carcass characteristics. A. awamori supplementation had a positive impact on immune responses by increasing serum immunoglobulin G and the relative weight of bursa of Fabricius (P < 0.05) compared to the other groups. Chickens fed A. awamori showed a noticeable improvement in the oxidative status through the increase in the level of serum superoxide dismutase, and glutathione peroxidase, and the decrease in the level of malondialdehyde. Feeding A. awamori also modified the intestinal microbial content by increasing the population of Lactobacillus (P < 0.05).ConclusionsOur study indicated that adding 200 mg A. awamori reduced the negative effect of heat stress by modifying the microbial content of the intestine, immune response, and enhancing feed utilization, thus improving broiler performance, as well as, improving the nutritional value of the olive pulp. Therefore, adding A. awamori to the OP diet can be effectively used in heat-stressed broiler diets.

A quantitative comparison of urine centrifugation and filtration for the isolation and analysis of urinary nucleic acid biomarkers

Urine is a rich source of nucleic acid biomarkers including cell-free DNA (cfDNA) and RNA for monitoring the health of kidney allografts. In this study, we aimed to evaluate whether urine filtration can serve as an alternative to the commonly used method of centrifugation to collect urinary fluid and cell pellets for isolating cfDNA and cellular messenger RNA (mRNA). We collected urine specimens from kidney allograft recipients and obtained the urine supernatant and cell pellet from each specimen using both filtration and centrifugation for paired analyses. We performed DNA sequencing to characterize the origin and properties of cfDNA, as well as quantitative PCR of mRNAs extracted from cell fractions. Our results showed that the biophysical properties of cfDNA, the microbial DNA content, and the tissues of origin of cfDNA were comparable between samples processed using filtration and centrifugation method. Similarly, mRNA quality and quantity obtained using both methods met our criteria for downstream application and the Ct values for each mRNA were comparable between the two techniques.The Ct values demonstrated a high degree of correlation. These findings suggest that urine filtration is a viable alternative to urine centrifugation for isolation of nucleic acid biomarkers from urine specimens.

Nutrient contents and microbial communities as mediators of the effects of land-use in ecosystem functioning in alpine ecosystems from Central Mexico

PurposeThe interplay between microbial taxonomy, functional diversity, and land-use changes across diverse ecosystems must be better understood. This study explores, through a statistical modeling approach, the intricate relationships between microbial communities, soil properties (nutrient contents and physicochemical parameters), and land-use changes, using stable isotopes ratio (δ13C/δ15N) as ecosystem function indicator.MethodsUsing Structural Equation Modeling (SEM) this study aims to investigate how soil microbial communities, soil properties and ecosystem function are interconnected in three ecosystems undergoing land-use change in Nevado de Toluca, Mexico.ResultsMultivariate analyses of microbial communities and soil parameters for the different land-uses reveal significant variation in both microbial composition and soil properties (i.e. nutrient contents) mainly explained by the land-use history of the studied ecosystems. Through the SEM approach, it was possible to disentangle the relative contribution of land-use change, microbial community composition and nutrient contents to the ecosystem function defined as the δ13C/δ15N ratio.ConclusionsMicrobial communities are the main drivers of soil ecosystem functioning. However, through SEM approach it is possible to formally test direct and indirect relationships impacting microbial communities and the resulting functional consequences, contributing to a mechanistic understanding of the ecological implications of land-use change, aiding in sustainable land-use decision-making.

Effectiveness of sodium alginate-based coating on the preservation of Da xanh pomelo fresh-cut

Pomelo (Citrus maxima (Burm. f.) Merr) fresh cut has a highly sensitive fruit and has a short shelf life after peeling. The fruits represent high potentials for local consumption and international export. The objective of the study was to focus on the effects of different concentrations of sodium alginate (1%, 1.5% and 2%) combined with fixed concentrations of calcium chloride (2%) and ascorbic acid (2.5%) to biologically active compounds and allowable microbial content on the surface pomelo fresh cut slices. The results showed that the presence of coating has improved several important quality parameters of the fruit. Specifically, the combination of AL (2%) + AA (2.5%) + calcium chloride (2%) Ascorbic acid (AA) has effectively maintained the total polyphenol content and the total ascorbic acid of the pomelo slice samples, thus exhibiting higher DPPH scavenging activity, as compared to control samples. Furthermore, the pomelo coated with alginate showed good conditions for consumption with minimal microbial degradation and describe good acceptance after 6 days of storage.

Effects of seasonal precipitation regimes on microbial biomass and extracellular enzyme activity during shrub foliar litter decomposition in a subtropical forest

Elucidating the mechanisms underlying microbial biomass and extracellular enzyme activity responses to the seasonal precipitation regime during foliar litter decomposition is highly important for understanding the material cycle of forest ecosystems in the context of global climate change; however, the specific underlying mechanisms remain unclear. Hence, a precipitation manipulation experiment involving a control (CK) and treatments with decreased precipitation in the dry season and extremely increased precipitation in the wet season (IE) and decreased precipitation in the dry season and proportionally increased precipitation in the wet season (IP) was conducted in a subtropical evergreen broad-leaved forest in China from October 2020 to October 2021. The moisture, microbial biomass, and extracellular enzyme activities of foliar litter from two dominant shrub species, Phyllostachys violascens and Alangium chinense, were measured at six stages during the dry and wet seasons. The results showed that (1) both IE and IP significantly decreased the microbial biomass carbon and microbial biomass nitrogen content and the activities of β-1,4-glucosidase, β-1,4-N-acetylglucosaminidase, acid phosphatase and cellulase in the dry season, while the opposite effects were observed in the wet season. (2) Compared with those of IE, the effects of IP on foliar litter microbial biomass and extracellular enzyme activity were more significant. (3) The results from the partial least squares model indicated that extracellular enzyme activity during foliar litter decomposition was strongly controlled by the foliar litter water content, microbial biomass nitrogen, the ratio of total carbon to total phosphorus, foliar litter total carbon, and foliar litter total nitrogen. These results provide an important theoretical basis for elucidating the microbial mechanisms driving litter decomposition in a subtropical forest under global climate change scenarios.

Properties of coaxial polycaprolactone cinnamaldehyde chitosan nanoparticles electrospun membrane and its effect on the shelf life of meat

Chilled meat is tender and juicy, with good nutritional content. In recent years, with the increasing demand for food quality, chilled meat has gradually replaced frozen meat as the mainstream choice for raw meat due to its nutritional value and freshness. However, chilled meat is highly susceptible to microbial infection and oxidative rancidity during storage. Chilled meat packaging can significantly extend the shelf life of chilled meat, which is of great significance for the development of the chilled meat industry and market. In this study, a sustainable electrospun membrane based on polycaprolactone mixed with cinnamaldehyde chitosan nanoparticles has been developed as a promising antibacterial fresh-keeping packaging membrane. Bacteria that cause foodborne illnesses are inhibited by cinnamaldehyde, an antimicrobial compound obtained from cinnamon essential oil. Chitosan nanoparticles can be used to wrap cinnamaldehyde essential oil to minimize the loss of this highly volatile oil during high-pressure spinning. Furthermore, its physical properties, antibacterial activity, and shelf life impact on pork were studied. In addition, the electrospinning film significantly reduced the microbial content, thiobapitur, pH value and volatile salt-based nitrogen content of chilled pork stockpiled at 4 °C for 12 days, prolonging the shelf life.

Seasonal changes of ammonia-oxidizing bacterial communities during tropical forest restoration

In this study, we used a high-throughput sequencing technology to survey the dry-wet seasonal change characteristics of soil ammonia-oxidizing bacteria (AOB) communities in the three restoration stages [i.e., Mallotus paniculatus community (early stage), Millettia leptobotrya community (middle stage), and Syzygium oblatum community (later stage)] of Xishuangbanna tropical forest ecosystems. We analyzed the effects of soil physicochemical characteristics on AOB community composition and diversity during tropical forest restoration. The results showed that tropical forest restoration significantly affected the relative abundance of dominant AOB phyla and their dry-wet seasonal variation. The maximum relative abundance of Proteobacteria (71.3%) was found in the early recovery stage, while that of Actinobacteria was found in the late recovery stage (1.0%). The abundances of Proteobacteria and Actinobacteria had the maximum ranges of dry-wet seasonal variation in the early and late stages, respectively. The abundance of dominant AOB genera and its dry-wet seasonal variation varied across tropical forest restoration stages. The maximum average relative abundance of Nitrosospira and Nitrosomonas in the late recovery stage was 66.2% and 1.5%, respectively. In contrast, the abundance of Nitrosovibrio reached its maximum (25.6%) in the early recovery stage. The maximum dry-wet seasonal variation in relative abundance of Nitrosospira and Nitrosomonas occurred in the early recovery stage, while that of Nitrosovibrio occurred in the middle recovery stage. The Chao1, Shannon, and Simpson diversity indices of AOB communities increased along the restoration stages, which were significantly higher in the wet season than in the dry season. The results of canonical correspondence analysis showed that soil easily oxidized carbon was the main factor controlling AOB community diversity and Actinobacteria abundance. Soil bulk density and temperature were the main factors affecting Proteobacteria abundance. Soil pH, microbial biomass carbon, water content, ammonium nitrogen, bulk density, and temperature were the main factors controlling the abundances of Nitrosospira, Nitrosomonas, and Nitrosovibrio. Therefore, tropical forest restoration can regulate the change of relative abundance of dominant AOB taxa via mediating the changes of soil temperature, bulk density, and readily oxidized carbon, leading to an increase in soil AOB community diversity.

Transfer of Exercise-Microbiome Is Suffcient to Induce a Shift in the Skeletal Muscle Metabolomic Profile without an Exercise Stimulus

Introduction: Skeletal muscle is a tissue that dynamically responds to disuse, which can induce rapid loss of mass and function. Identification of novel drug candidates will facilitate the development of supportive therapies for extended periods of decreased mobility, both planned and unanticipated. Recent findings from our lab as well as others indicate the important role of the gut microbiome in mediating the beneficial effects of exercise. Hypothesis: Transfer of microbiome from excise-trained mice into exercise-naïve mice will induce metabolic adaptations in the recipient skeletal muscle. Method: Sedentary and exercise-trained mice were used as donors for microbiome transfer. Exercise training consisted of 8-weeks of processive weighted wheel running. Exercise-naïve recipient mice were bowel cleansed with polyethylene glycol and transplanted with either sedentary (SED) or exercise-trained (EXER) donor microbiome. Recipient cecal content, serum, and gastrocnemius muscle were collected for untargeted metabolomics using liquid chromatography mass spectrometry. Results: Partial Least Squares Discriminant Analysis indicated significant metabolic discrimination between EXER and SED in all samples (cecal, serum, and muscle). Variable Importance in Projection scores identified several metabolites as significant discriminating metabolic features between EXER and SED, including ones involved in the TCA cycle, lysine and fatty acid degradation pathways. Conclusion: Transfer of microbial content from exercise-trained mice is suffcient to induce changes in muscle metabolite profile reminiscent of exercise in the absence of such a stimulus. Funding: This work is supported by the National Institute on Aging (AG071888). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

The gut-brain-axis: A positive relationship between gut microbial dysbiosis and glioblastoma brain tumour

The glioblastoma brain tumour (GBM) stands out as the most aggressive and resistant-to-treatment malignancy. Nevertheless, the gut-brain connection plays a pivotal role in influencing the growth and activation of the central nervous system. In this particular investigation, we aimed to assess and characterize the gut microbial ecosystem in GBM patients, both quantitatively and qualitatively. We collected faecal samples from 15 healthy volunteers and 25 GBM patients. To delve into the microbial content, we employed PCR-DGGE, targeting the V3 region of the 16S rRNA gene, and conducted qPCR to measure the levels of crucial intestinal bacteria. For a more in-depth analysis, high-throughput sequencing was performed on a selection of 20 random faecal samples (10 from healthy individuals and 10 from GBM patients), targeting the V3+V4 region of the 16S rRNA gene. Our findings from examining the richness and diversity of the gut microbiota unveiled that GBM patients exhibited significantly higher microbial diversity compared to healthy individuals. At the phylum level, Proteobacteria saw a significant increase, while Firmicutes experienced a noteworthy decrease in the GBM group. Moving down to the family level, we observed significantly elevated levels of Enterobacteriaceae, Bacteroidaceae, and Lachnospiraceae in GBM patients, while levels of Veillonellaceae, Rikenellaceae, and Prevotellaceae were notably lower. Delving into genera statistics, we noted a substantial increase in the abundance of Parasutterella, Escherichia-Shigella, and Bacteroides, alongside significantly lower levels of Ruminococcus 2, Faecalibacterium, and Prevotella_9 in the GBM group compared to the control group. Furthermore, when examining specific species, we found a significant increase in Bacteroides vulgatus and Escherichia coli in the GBM group. These observations collectively indicate a marked dysbiosis in the gut microbial composition of GBM patients. Additionally, the GBM group exhibited notably higher levels of alpha diversity when compared to the control group. This increase in diversity suggests a significant bacterial overgrowth in the gut of GBM patients in contrast to the controls. As a result, this research opens up potential avenues to gain a better understanding of the underlying mechanisms, pathways, and potential treatments for GBM, stemming from the significant implications of gut microbial dysbiosis in these patients.

A non-invasive tool to collect small intestine content in post weaning pigs: validation study.

The Capsule for Sampling (CapSa) is an ingestible capsule that collects small intestine content while transiting through the natural digestive pathway. In this study, 14 Swiss Large White pigs weighing less than 12kg (Category < 12kg) and 12 weighing between 12 and 20kg (Category [12-20kg]) were given two CapSas and monitored for three days. The animals were euthanized for post-mortem sampling, allowing us to directly obtain gut microbiota samples from the gastrointestinal tract. This post-mortem approach enabled a direct comparison between the microbial content from the gut and the samples collected via the CapSas, and it also facilitated precise identification of the CapSas' sampling sites within the gastrointestinal tract. For the category under 12kg, only 2.3% of the administered CapSas were recovered from the feces. In contrast, in the 12-20kg category, 62.5% of the CapSas were successfully retrieved from the feces within 48h. Of these recovered CapSas, 73.3%-equating to 11 capsules from eight pigs-had a pH > 5.5 and were therefore selected for microbiome analysis. Bacterial composition of the CapSas was compared with that of the three segments of the small intestine, the large intestine and feces of the corresponding pig. The results were tested using a PERMANOVA model (Adonis) including sample type as a factor, and then pairwise comparisons were made. The bacterial composition found in the CapSas differed from that of the large intestine and feces (P < 0.01), while it did not differ from the first segment of the small intestine (P > 0.10). This study provides evidence that the CapSa effectively samples the intestinal microbiota from the upper section of the small intestine in post-weaning pigs. Furthermore, it was found that the collection of CapSas could only be successfully achieved in pigs classified within the heavier weight category.

The Impact of Oxygen and Ascorbic Acid Treatments on the Physicochemical Attributes of Live Sea Cucumber During Extended Transportation/Storage

ABSTRACT Sea cucumbers were stored live in 25% oxygen or 25 mg/mL of ascorbic acid for 7 days, for comparison purposes. The condition of the individuals was assessed through the sensory scores, bacterial communities, and biochemical indexes. The oxygen treatment extended preservation by 2 days compared to ascorbic acid. After 7 days, the total volatile basic nitrogen and the microbial content in all sea cucumbers were within acceptable limits. The actin degradation rate reached 1.3416 ± 0.03%, and cathepsin B and L increased by 94.6% and 59.1%, respectively, in the Control group. The quality decline of sea cucumbers during storage was caused by autolysis rather than spoilage organisms.

Chemical, microbial, and volatile compounds of water kefir beverages made from chickpea, almond, and rice extracts

This study aims to assess the microbial, nutritional, volatile, and sensory characteristics of rice, almond, and chickpea water kefir beverages during refrigerated storage. Plant-based kefirs contained significant amounts of lactic acid bacteria and yeasts. The microbial content of kefirs was stable during 14-day refrigerated storage. Lactic acid, acetic acid, and tartaric acid are commonly detected organic acids in kefir samples. Almond and chickpea kefirs were rich in potassium mineral. Almond kefir had the highest ethanol content among plant-based kefirs, followed by chickpea and rice-based kefirs. Ethyl acetate, acetic acid, propionic acid, hexanoic acid, and benzenemethanol were identified as key volatile compounds in almond kefir and chickpea kefir samples using a GC–MS detector during water kefir fermentation. According to sensory analysis results, significant differences are present for all test parameters except odor. Almond kefir was the most accepted, while the other two kefir samples were below the general acceptance level (P < 0.05).

Biology of tongue coating in different disease stages of RA and its value in disease progression

ObjectiveTo assess and compare the composition of tongue coating microbiota among patients at different stages of rheumatoid arthritis (RA). MethodsA total of 47 patients diagnosed with RA, as per the American College of Rheumatology criteria, and 10 healthy individuals were enrolled in this study. The RA patients were stratified considering their Disease Activity Score 28 (DAS28), a composite measure based on the 28 tender and swollen joint count and erythrocyte sedimentation rate (ESR). The study population was further categorized into active phase group (LMH group) and inactive phase group (RE group) according to their DAS28 values. DNA extraction was extracted from tongue coating samples. Subsequently, the V3–V4 16S rDNA region was selectively amplified and sequenced through high-throughput 16S rDNA analysis. The resulting data were then utilized to ascertain the microbial contents. ResultsSignificant variations were observed in the tongue coating microbiota of patients with RA during active and inactive phases, in comparison to healthy individuals (p < 0.05). At the genus level, the presence of Prevotellan, Veillonella, Rothia, and Neisseria in RA patients was notably more evident than in the healthy control (HC) group. These disparities find support in existing research on gut and oral microbiota. During the active phase of RA, the relative abundance of Veillonella, Rothia, and Neisseria in the tongue coating microbiota of patients was significantly higher than in those with inactive RA. These findings underscore the need for further and in-depth research on the potential impact of these microorganisms on the progression of RA disease. ConclusionThe results substantiate the hypothesis that tongue coating microbes actively contribute to the progression of RA.

Analysis of Microbial Composition of Edible Insect Products Available for Human Consumption within the United States Using Traditional Microbiological Methods and Whole Genome Sequencing

Edible insects offer a promising protein source for humans, but their food safety risks have not been previously investigated within the United States. Therefore, the aim of this study was to investigate the microbial content of processed edible insect products. A total of eight different types of edible insect products, including diving beetles, silkworms, grasshoppers, Jamaican crickets, mealworms, mole crickets, whole roasted crickets, and 100% pure cricket powder, were purchased from a large online retailer for the analysis. All the products were purchased in August 2022 and examined between August 2022 and November 2022. Traditional microbiological methods were employed to determine microbial counts for each product type using three replicates (total number of samples = 24). This included assessing aerobic bacterial spore, lactic acid bacteria, Enterobacteriaceae, total viable counts, and the presence of Salmonella. Additionally, whole genome sequencing was employed to further characterize selected colonies (n = 96). Microbial counts data were statistically analyzed using one-way ANOVA, while sequence data were taxonomically classified using Sepia.Bacilluscereusgroup isolates underwent additional characterization with Btyper3. Product type significantly influenced total viable counts, bacterial spore counts, and lactic acid bacteria counts (P = 0.00391, P = 0.0065, and P < 0.001, respectively), with counts ranging from < 1.70 to 6.01 Log10 CFU/g, <1.70 to 5.25 Log10 CFU/g, and < 1.70 to 4.86 Log10 CFU/g, respectively. Enterobacteriaceae were only detected in mole crickets (<2.30 Log10 CFU/g) and house cricket powder (<2.15 Log10 CFU/g). All samples were negative for Salmonella. Whole genome sequencing revealed the presence of 12 different bacterial genera among the analyzed isolates, with a majority belonging to the Bacillus genus. Some of the isolates of Bacillus cereus group were identified as biovar Emeticus. Overall, although edible insects offer a promising food alternative, the presence of Bacillus cereus group in some products could raise concerns regarding food safety.

Food safety knowledge and practices among raw meat handlers and the microbial content of raw meat sold at Kumasi Abattoir Butchery Shops in Kumasi, Ghana

BackgroundFoodborne diseases affect nearly 600 million people each year, that is, one in every ten people, and their outbreaks are most common in low- and middle-income countries, particularly in Africa. This study investigated the food safety practices among raw meat handlers and the microbial quality of the meat from the butchery shops in Kumasi Abattoir, Ghana.MethodsThis study employed a descriptive cross-sectional study and collected quantitative data on factors associated with food safety and hygienic practices among raw meat handlers and the microbial quality of the raw meat using a structured questionnaire and standard laboratory methods, respectively. The study used all 50 beef vending shops in the butchery for questionnaire aspect and fresh beef samples were obtained from 10 vendors in the butchery shop. Appropriate methods were followed to analyse questionnaire data and meat samples.ResultsMost of the butchers (72%) were between the ages of 31 and 45, and they were predominantly Muslims (68%). Most of the respondents (48%) had basic education. All the respondents had food safety certificates from the local authority but needed adequate knowledge of meat safety. Most respondents (90%) handled meat and money with the same bare hands, thus contaminating the meat. The study showed that the maximum Total Viable Count (TVC), Total Staphylococcus Count (TSC), and Total Escherichia coli Count (TEC) were 5.60, 4.39 and 5.13 cfu/g, respectively. The study also revealed that all the meat samples were Salmonella species-free.ConclusionsMicroorganisms in raw beef indicate a public health hazard. It gives a signal of a possible occurrence of food-borne intoxication and infection if not controlled. Environmental health officers in the Greater Kumasi area should organize food safety training and educate raw meat handlers on the importance of food safety and its consequences.

Microbial Community Structure in Anaerobic Digestion for Green Energy Production: A Mini Review

Anaerobic digestion (AD) is a process driven by microbes that supports renewable energy production, together with waste utilization. The role of microorganisms is undisputable as they are involved in the subsequent processes of hydrolysis, acidogenesis, acetogenesis, and methanogenesis. Microbial communities vary in wide ranges, depending on the type of substrates used and the conditions provided. Anaerobic systems are addressed, operating under mesophilic and thermophilic conditions for the biodegradation of agricultural wastes for biogas/biomethane production. AD comprises successive degradation pathways and syntrophic microbial consortia activities. Identifying the microbial content in digesters could help attaining new information on the digester performance. Archaeal and bacterial associations have to be determined as their important role to be elucidated. Molecular-biological methods of metagenomics are applied to identify the residing mixed cultures therein. Methanogens have been attained to the domain Archaea. Bacterial and archaeal populations, specific for each stage are differentiated in thermophilic or mesophilic conditions as temperature plays a crucial role in AD process, especially for hydrolysis and methanogenesis and determines microorganisms’ variety

Development of a rhodamine-based fluorescent probe for ATP detection for potential applications in meat freshness assessment

Adenosine triphosphate (ATP) plays a vital role in physiological processes and is an essential indicator of microbial content in food. Herein, a new sensitive, rapid and water-soluble probe for ATP detection was developed. Rhodamine B and pentaethylenehexamine were employed to design and synthesise the probe rhodamine-pentaethylenehexamine (RP) for selective ATP detection. The synthesised probe RP was characterized using Fourier transform infrared, NMR and dynamic light scattering size distributions. Upon the addition of ATP, the probe exhibited a distinct change in fluorescence intensity, with fluorescence emission at 580 nm. A linear relationship was observed between fluorescence intensity and ATP concentrations at 0–50 μmol/L, with a limit of detection of 10.97 × 10−9 mol/L. The results of the zeta potential and molecular dynamics simulation demonstrated that the detection mechanism of the probe RP is associated with the electrostatic adsorption interaction between the multi-positively charged sites of RP and the negatively charged triphosphate structure of ATP. Our study provides new insights into improving charge site identification in small molecule detection. Furthermore, the successful detection of ATP on meat surfaces indicates that RP has the potential to assess meat freshness.

Swapping white for high-fibre bread exceeds fibre target and improves microbiome diversity

A majority of Australians consume a limited range of different dietary fibres and insufficient total dietary fibre(1). This contributes to low intestinal microbial diversity and impaired microbial function, such as capability in producing beneficial metabolites like short-chain fatty acids (SCFA). This diet-induced dysbiosis is associated with poor gastrointestinal health and a broad range of non-communicable diseases(2). Our study aimed to determine whether one dietary change, substitution of white bread with a high fibre bread improves faecal microbial diversity and butyrate-producing capability. Twenty-six healthy adults completed a randomised, cross-over, single-blinded intervention. Over the two intervention phases separated with a 4-wk washout, participants consumed either 3 slices of a high fibre bread (Prebiotic Cape Seed Loaf with BARLEYmax®) or control white bread as part of the usual diet, each for 2 weeks. At the beginning and end of each intervention period, participants completed a 24-h diet recall, a gut symptoms rating questionnaire and provided a faecal sample for microbiome analysis. The composition of faecal microbiome was characterised using 16S rRNA amplicon sequencing (V3-V4) and a marker of butyrate synthesis capability, the faecal content of butyryl-CoA:acetate CoA-transferase (BCoAT) gene was assessed using Real-time PCR. The high fibre bread intervention increased the servings of whole grain from 1.5 to 4 per day and increased total dietary fibre intake to 40 g/d which was double the amount of fibre consumed by participants at baseline or during the white bread intervention. Compared to white bread, the high fibre bread increased richness and evenness (Shannon, p = 0.014) of the gut microbiota and increased the relative abundance of SCFA producing taxa Lachnospiracae ND3007 group (p &lt;0.001, FDR = 0.019). In addition, the high-fibre bread tended to increase relative abundance of butyrate-producing genus Roseburia, and microbial BCoAT gene content compared to white bread. In conclusion, the substitution of white bread with high-fibre bread improved the diversity of gut microbiota, specific microbes involved in SCFA production and may enhance the butyrate production capability of gut microbiota in healthy adults.

Long‐term straw mulching alleviates microbial nutrient limitations and increases carbon‐use efficiency within aggregates

AbstractLong‐term straw mulching was known to change soil nutrient content, aggregate distribution and extracellular enzyme activities. However, the impact of long‐term straw mulching on microbial nutrient limitations and carbon‐use efficiency (CUEst) within aggregates remains unclear. To fill the gap, we conducted a 10‐year field experiment in a semi‐arid region and used an ecoenzymatic stoichiometry model to quantify microbial resource limitations in soil aggregates under long‐term mulching. We studied the effects of two mulching measures (plastic film mulching [FM] and straw mulching [SM], with no mulching as the control [CK]) on the nutrient content and limitations within aggregates. The results show that compared with FM, SM increased the proportion of aggregates to larger &gt;2 mm and decreased the proportion of aggregates in the 2–0.25 mm classes. Additionally, FM resulted in carbon (C) and phosphorus (P) limitations in the soil, particularly in the &gt;2 mm class, while SM alleviated these constraints. This effect was primarily attributed to the increase in soil organic carbon (SOC) and microbial biomass carbon content (Cm), especially the enhanced carbon content associated with larger aggregates (&gt;2 mm) and the increased activities of carbon–nitrogen (C–N)‐acquiring enzymes. SM also resulted in high CUEst by influencing microbial P limitation. Random forest analysis indicates that soil abiotic factors, particularly SOC and total nitrogen (TN), were the main drivers of microbial resource limitations within the aggregates. These findings suggest that the mulching material determines the development of soil aggregates and resource allocation within these aggregates. Thus, the study provides valuable insights for formulating effective carbon management strategies in semi‐arid regions.

Isolation Identification and Molecular Characterization of Lactic Acid Bacteria From Raw Milk Samples Collected from Erzurum Region

Due to its high-water content, milk is an important source of different microbial contents, especially lactic acid bacteria. The aim of this study is to isolate and identify lactic acid bacteria from raw milk samples collected from Erzurum and its surroundings, and to introduce possible new species, or genera, to the taxonomy. For this purpose, DNAs of pure bacterial cultures obtained from 50 raw milk samples collected from producers in Erzurum and its districts were isolated, isolates that differed from each other were selected by rep-PCR, and 11 different species and subspecies [Corynebacterium casei, Enterococcus italicus, E. durans, Lactococcus lactis, Lactococcos lactis subsp. lactis, Lactococcos lactis subsp. hordniae, Lactobacillus paracasei, Leuconostoc lactis, Staphylococcus succinis, Streptococcus parauberis ve S. uberis] in raw milk samples by 16S rRNA sequence analysis. It was concluded that the (GTG)5-PCR method was more successful than BOX-PCR in the identification of lactic acid bacteria isolated from raw milk samples at a species and subspecies level, and the isolate coded TS10, which was 98% similar Streptococcus uberis, may be a new species and should be re-examined with advanced diagnostic techniques.