Fecal Microorganisms Research Articles

Structural characterization of alkali-extracted jujube polysaccharides and their effects on the fecal microbiota in vitro

The structural characteristics of alkali-extracted jujube polysaccharides and their effects of in vitro fermentation on fecal microorganisms were evaluated in this study. Scanning electron microscopy revealed that AJP1 and AJP2 polysaccharides had different morphological characteristics, and their molecular weights were 75465 Da and 268007 Da, respectively. The uronic acid contents of the two polysaccharides were 79.68% and 77.64%. Infrared spectroscopy showed that two alkaline-extracted polysaccharide groups had characteristic absorption peaks of acidic polysaccharides such as C=O and C-H. After 48 h of in vitro fermentation, the total sugar consumption rates of the AJP1 and AJP2 treatments reached 65.40% and 56.24%, respectively. During the fermentation process, the pH values of the polysaccharide-treated groups were significantly lower compared to the control group. In addition, polysaccharides could promote the abundance, diversity, and composition of gut microbiota. These results showed that alkali-extracted jujube polysaccharides could regulate the intestinal microflora composition in feces, and inhibit the growth of pathogenic bacteria Peptoniphilus and Desulfovibrio while promoting the growth of beneficial bacteria such as Megamonas and Allisonella. This study provides a reference for further developing jujube polysaccharide functional food products and the study of the structure-activity relationship between alkali-extracted polysaccharides and intestinal flora.

Perturbations in gastrointestinal tract microbiota composition and function in individuals with yellow-greasy tongue coating

ObjectiveTo study the composition and function of tongue coating (TC) and gastrointestinal tract (GIT) microbiota in participants with yellow-greasy tongue coating (YGTC), and to explore the representative metabolite markers and pathways in this group. MethodsSubjects with YGTC or thin-white tongue coating (TWTC) were recruited from December 1, 2021 to October 30, 2022, and the TC and fecal samples were collected. Samples were subjected to both whole-genome shotgun (WGS), and 16S rRNA gene sequencing. The α-diversity analysis, principal component analysis (PCA), and Spearman correlation analysis were performed for two groups. Ultra-performance liquid chromatography combined with tandem mass spectrometry (UPLC–MS/MS) analysis was used to analyze metabolomics and enrichment of metabolic pathways. ResultsThe results revealed 20 YGTC participates and 19 TWTC participates. At the genus level, the dominant bacterial species of TC flora and intestinal flora in the two groups were roughly the same, but the relative kurtosis difference was marked, and the abundance of potentially pathogenic bacteria in TC and fecal samples of YGTC subjects was higher. There were 9 down-regulated microorganisms in the TC samples, 26 down-regulated microorganisms, and 6 up-regulated microorganisms in YGTC subjects. The α-diversity analysis indicated that the Chao and abundance-based coverage estimator (ACE) indices of TC bacteria in the YGTC subjects showed a decreasing trend, but the difference was not statistically significant (P > 0.05). The α-diversity of fecal samples and the Chao and ACE indices decreased significantly (P < 0.05). PCA showed that the microflora structure of TC and fecal samples were significantly different between the two groups. Spearman correlation analysis showed that there was no correlation between TC and fecal microorganisms at phyla and genus levels in the same subjects (P > 0.05). The metabolomics results demonstrated that fumarate reductase, V/A ATPase, and phosphatidylethanolamine were increased, and glycerate-3p, UDP-glucose, and quinone oxidoreductase metabolites were decreased in YGTC TC samples. Inosine monophosphate (IMP), uridine monophosphate (UMP), and gamma-aminobutyric acid (GABA) were increased in YGTC fecal samples, while the contents of ribo-5P, histidine, biotin, and cobalamin were decreased. Metabolic pathway analysis indicated that the abundance of the TC and fecal samples of the YGTC subjects was relatively low in various metabolic pathways, including amino acid metabolism, carbohydrate metabolism, nitrogen metabolism, and energy metabolism. ConclusionStructural and functional changes in TC and GIT microbiota or metabolite markers could be potential biological bases of YGTC formation.

Chemically Modified TiO2 Photocatalysts as an Alternative Disinfection Approach for Municipal Wastewater Treatment Plant Effluents

Among key issues in municipal wastewater treatment plants (MWTP) is the existence of pathogenic bacteria in the discarded effluents. Conventional disinfectants (ozone, UV irradiation, chlorine) have been insufficient in providing safe water due to the development of undesirable and noxious by-products. TiO2 comprises an attractive alternative to conventional methods because of its versatility and recently explored biocidal efficiency. As a result, within the framework of this study, chemically modified, visible active nanocrystalline TiO2 powders (N-TiO2, N,S-TiO2, and Ag@N-TiO2) were prepared via a low-cost, feasible sol-gel method for the treatment of real municipal wastewater effluents. Wastewater samples were acquired from the outlet of the treatment of Antiparos (Cyclades, Greece) MWTP during the summer period in which a great number of seasonal habitants and tourists usually visit the island, resulting in at least a doubling of the population. All synthesized powders were thoroughly characterized using various morphological and spectroscopic techniques, such as FE-SEM, XRD, micro-Raman, FTIR, DLS, UV-DRS, and XPS. Photocatalytic evaluation experiments were initially conducted towards Rhodamine B degradation under visible light irradiation. Among all studied powders, Ag@N-TiO2 indicated the highest efficiency, reaching total degradation (100%) of RhB within 240 min due to its smaller crystallite size (1.80 nm), enhanced surface area (81 m2g−1), and reduced energy band gap (Eg = 2.79 eV). The effect of the produced powders on the disinfection as assessed in terms of fecal indicator microorganisms (E. coli and total coliforms) inactivation was also examined in a semi-pilot scale-up photocatalytic reactor. Ag@N-TiO2 nanopowder was also found substantially more active for both groups of bacteria, leading to complete inactivation in less than 35 min, probably due to the higher production of H2O2/•OH, as emerged from the photocatalytic mechanism study. In addition, Ag@N-TiO2 nanoparticles demonstrated excellent photocatalytic and disinfection stability even after five subsequent recycling trials (8.34% activity loss and complete inactivation, respectively). The results of the present study demonstrate the feasibility for Ag@N-TiO2 to be utilized as a viable, eco-friendly approach for the photocatalytic pathogenic bacteria inactivation as an alternative disinfection approach for municipal wastewater treatment plant effluents with intense seasonal fluctuations in volume.

MicroRNA-29a Compromises Hepatic Adiposis and Gut Dysbiosis in High Fat Diet-Fed Mice via Downregulating Inflammation.

miR-29a expression patterns influence numerous physiological phenomena. Of note, upregulation of miR-29a ameliorates high-fat diet (HFD)-induced liver dysfunctions in mice. However, the miR-29a effect on gut microbiome composition and HFD-induced gut microbiota changes during metabolic disturbances remains unclear. We provide compelling evidence for the protective role of miR-29a in gut barrier dysfunction and steatohepatitis. We bred miR-29a overexpressed mice (miR-29aTg) to characterize intestinal, serum biochemical, and fecal microbiota profiling features compared to wild-type mice (WT). Mice were fed an HFD for 8 months to induce steatohepatitis, and intestinal dysfunction was determined via histopathological analysis. miR-29aTg had better lipid metabolism capability that decreased total cholesterol and triglyceride levels in serum than WT of the same age. We further demonstrated that miR-29aTg contributes to intestinal integrity by maintaining periodic acid Schiff positive cell numbers and diversity of fecal microorganisms. HFD-induced bacterial community disturbance and steatohepatitis resulted in more severe WT than miR-29aTg. Gut microorganism profiling revealed Lactobacillus, Ruminiclostridium_9, and Lachnoclostridium enrichment in miR-29aTg and significantly decreased interleukin-6 expression in the liver and intestinal tract. This study provides new evidence that sheds light on the host genetic background of miR-29a, which protects against steatohepatitis and other intestinal disorders. This article is protected by copyright. All rights reserved.

Ganjiang Huangqin Huanglian Renshen Decoction improves insulin sensitivity by regulating intestinal flora in rats with Type 2 diabetes mellitus

Purpose: To study the effect of Ganjiang Huangqin Huanglian Renshen Decoction (GHHRD) on intestinal microflora and insulin resistance (IR) in type 2 diabetes mellitus (T2DM) rats. &#x0D; Methods: Streptozotocin (STZ) injection was used to establish a rat model of T2DM. The T2DM rats were divided into 5 groups: control, T2DM, T2DM + low-dose traditional Chinese medicine (TCM), T2DM + high-dose TCM, and T2DM + metformin groups. Total DNA kit was used for extraction of total DNA from fecal microorganisms from the T2DM model rats. High-throughput 16S rDNA sequencing was carried out to identify the intestinal flora of T2DM model rats. Fasting plasma glucose (FPG) and fasting serum insulin (FINS) levels were determined by a biochemical analyzer. &#x0D; Results: The 16S rDNA sequencing analysis showed that after GHHRD treatment, the levels of Ruminococcus, Prevotellaceae, Escherichia-Shigella and Bacteroidota in the intestinal tract of T2DM model rats exhibited significant changes. Furthermore, GHHRD decreased the Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) index and IR in T2DM model rats. &#x0D; Conclusion: GHHRD mitigates IR in T2DM model rats through alterations in the intestinal flora of the rats. This provides a theoretical basis for the potential use of GHHRD in the clinical management of T2DM.

The level of aquatic yeast as a possible indicator of microbiological quality of urban recreational water reservoirs

ABSTRACT Sanitary indicators standardly used in water quality monitoring refer to fecal microorganisms or cyanobacterial toxins, but at present they do not include fungi, despite the fact that many fungi can pose potential health hazards. The aim of study was a quantitative and qualitative assessment of yeast in waters of urban artificial recreational reservoirs in relation to microbiological and sanitary cleanliness indicators and to demonstrate that yeast could be an indicator of anthropogenic pollution. In total, 18 species of yeast were isolated, including 13 classified as clinically relevant. Tested reservoirs exceeded the standards of sanitary indicators acceptable for bathing water. Since isolated yeasts are associated with living organisms, their presence in the water of urban recreational reservoirs may be a public health concern. Therefore, a mycological analysis should be incorporated into standard water quality assessment procedures. The results obtained are very promising, but further research is still needed.

Water disinfection by persulfate activation using a nitrogen-doped reduced graphene oxide – PVDF membrane

This work demonstrates the suitability of employing carbon-based catalytic membranes for persulfate activation and water disinfection in continuous flow mode of operation for the first time. Poly(vinylidene fluoride) (PVDF) membranes with and without nitrogen-doped reduced graphene oxide (rGO-M) were prepared and tested. The cumulative effect of each membrane component was assessed based on the persulfate activation capacity and the retention and/or elimination of faecal contamination indicator microorganisms in a defined suspension of Escherichia coli and Enterococcus faecalis. In the absence of persulfate, the pristine PVDF membrane enabled retention of 1.98 ± 0.51 log, while the rGO-M–PVDF membrane removed 3.71 ± 0.66 log of the initial microbial abundance (3.87 ± 0.01 log) after 6 h of operation. The catalytic features of the rGO-M–PVDF membrane were then demonstrated by adding a persulfate precursor to the feed suspension. This treatment system was able to reduce the abundance of cultivable microorganisms (total heterotrophs, enterobacteria, enterococci) of the defined suspensions and river water samples to values below the limit of detection (< 0.5 CFU mL−1) up to 24 h operation. In addition, the reactivation capacity of the cultivable microorganisms and representative specific genes (16S rRNA, intl1, blaTEM and sul1) after 7-day storage of the treated river water was studied. Among the parameters analysed, only total cultivable heterotrophic cells were able to regrow to values similar to those found in the feed. Therefore, the proposed system can be considered as a promising technology for the removal of harmful microbiota during drinking water production in continuous flow mode.

ROS Scavenging and inflammation-directed polydopamine nanoparticles regulate gut immunity and flora therapy in inflammatory bowel disease.

Dysfunction of the intestinal mucosal immune system and dysbiosis of the intestinal microflora can induce inflammatory bowel disease. However, drug-mediated clinical treatment remains a challenge due to its poor therapeutic efficacy and severe side effects. Herein, a ROS scavenging and inflammation-directed nanomedicine is designed and fabricated by coupling polydopamine nanoparticles with mCRAMP, an antimicrobial peptide, while wrapping macrophage membrane in the outer layer. The designed nanomedicine reduced the secretion of pro-inflammatory cytokines and elevate the expression of anti-inflammatory cytokine in vivo and in vitro inflammation models, demonstrating its significant ability of improving inflammatory responses. Importantly, the macrophage membrane encapsulated nanoparticles exhibit the obviously enhanced targeting performance in local inflamed tissues. Furthermore, the 16S rRNA sequencing of fecal microorganisms showed that probiotics increased and pathogenic bacteria were inhibited after oral delivery the nanomedicine, indicating that the designed nano platform played a significant role in optimizing intestinal microbiome. Taken together, the designed nanomedicine are not only easy to prepare and exhibit high biocompatibility, but also show the inflammatory targeting property, anti-inflammatory function and positive regulation of intestinal flora, thus providing a new idea for the intervention and treatment of colitis. STATEMENT OF SIGNIFICANCE: Inflammatory bowel disease (IBD), a chronic and intractable disease, may lead to colon cancer in severe cases without effective treatment. However, clinical drugs are largely ineffective owing to insufficient therapeutic efficacies and side effects. Herein, we constructed a biomimetic polydopamine nanoparticle for oral administration to treat the IBD by modulating mucosal immune homeostasis and optimizing intestinal microorganisms. In vitro and in vivo experiments showed that the designed nanomedicine not only exhibits the anti-inflammatory function and inflammatory targeting property but also positively regulate the gut microflora. Taken together, the designed nanomedicine combined immunoregulation and intestinal microecology modulation to significantly enhance the therapeutic effect on colitis in mice, thus providing a new approach for the clinical treatment of colitis.

The microbiota in feces of domestic pigeons in Seoul, Korea

In Korea, feral pigeons pose significant public health risks because they carry various zoonotic pathogens. Human population density is a significant factor in zoonotic disease events. Seoul is one of the largest cities by population density among developed countries and where most of the homeless population in Korea exists. We designed this study to compare the microbiota of pigeon feces by regional characteristics and the presence of homeless individuals. Therefore, this study used 16S rRNA amplicon sequencing to detect possible pathogenic microbes and assess the current risk of zoonosis in Seoul, South Korea. Pigeon fecal samples (n = 144) obtained from 19 public sites (86 and 58 fecal samples from regions in and outside Seoul, respectively) were examined. Potentially pathogenic bacteria were also detected in the fecal samples; Campylobacter spp. was found in 19 samples from 13 regions, Listeriaceae was found in seven samples, and Chlamydia spp. was found in three samples from two regions. Principal coordinates analysis and permutational multivariate analysis of variance revealed a significant difference in bacterial composition between the regions in Seoul (n = 86) and outside Seoul (n = 58) and between the regions with (n = 81) and without (n = 63) homeless individuals. Overall, this study identified various potentially pathogenic microorganisms in pigeon feces at public sites in South Korea. Moreover, this study demonstrates that the microbial composition was influenced by regional characteristics and homelessness. Taken together, this study provides important information for public health strategic planning and disease control.

Effects of milk-derived bioactive peptide VPP on diarrhea of pre-weaning calves.

A well-known milk-derived bioactive tripeptide, VPP (Val-Pro-Pro) has good anti-inflammatory, anti-hypertension, and anti-hydrolysis properties. However, whether VPP can alleviate calf intestinal inflammation is unclear. In this experiment, the effects of VPP on growth, diarrhea incidence, serum biochemical indices, short-chain fatty acids, and fecal microorganisms were examined in pre-weaning Holstein calves. Eighteen calves with similar birth date, body weight, and genetic background were randomly assigned equally to two groups (n = 9). The control group was given 50 mL of phosphate buffer saline before morning feeding, whereas the VPP group received 50 mL of VPP solution (100 mg/kg body weight/d). The study lasted for 17 days, with the first 3 days used for adaptation. Initial and final body weights were determined, and daily dry matter intake and fecal score were recorded throughout the study. Serum hormone levels and antioxidant and immune indices were measured on day 14. Fecal microorganisms were collected on days 0, 7, and 14, and 16S rDNA sequencing was performed. Oral administration of VPP did not significantly affect calf average daily feed intake and body weight, but the growth rate in body weight was significantly higher in the VPP group than in the control group on day 7 (P < 0.05). Compared with the control, VPP significantly decreased serum TNF-α and IL-6 contents (P < 0.05), and concentrations of nitric oxide and IL-1β also decreased but not significantly (0.05 < P < 0.1). After seven days of VPP, relative abundances of g_Lachnoclostridium, uncultured_bacterium_, and g_Streptococcus in fecal samples increased significantly (P < 0.05). Compared with the control, VPP significantly increased concentrations of the fecal short-chain fatty acids n-butyric acid and isovaleric acid (P < 0.05). In conclusion, VPP can relieve intestinal inflammation and alleviate the degree of diarrhea in pre-weaning calves.

Influence of pressure in a point-of-use treatment of well water using gravity-driven ultrafiltration membranes for drinking purposes in developing countries

The use of polymeric membranes that do not require electricity and cleaning is an attractive technology for use in the point-of-use (POU) treatment of water in areas where access to drinking water is limited. This study sought to evaluate the performance of a biofilm-controlled gravity-driven membrane (GDM) in the treatment of well water contaminated with fecal microorganisms and to validate the operating and maintenance concepts described in the literature. The effects of different pressures (50, 70, and 100 mbar) were tested using a 100,000 Da ultrafiltration (UF) membrane across 129 days of continuous filtration. After stabilization, the system achieved average permeate fluxes of 4.4 ± 0.2 L m−2 h−1, 4.7 ± 0.3 L m−2 h−1, and 6.5 ± 0.4 L m−2 h−1, and total membrane resistances of 4.2 × 1012 m−1, 5.4 × 1012 m−1, and 5.5 × 1012 m−1 for the hydraulic loads of 50, 70, and 100 mbar, respectively. An analysis of the filtrates showed a 3-log removal efficiencies for E. coli in all filters, producing water that was in compliance with potability standards. The average turbidity removal efficiencies were 72 %, 74 %, and 50 % for hydraulic loads of 50, 70, and 100 mbar, respectively. The total organic carbon content and the ultraviolet absorption at 254 nm were reduced by 7–17 % and 10–30 %, respectively. The membrane did not affect the removal of chlorides and sulfates. The biofilm, developed in an oligotrophic environment, contributed to the filtration of a constant amount of water (flux stabilization) but did not improve the quality of the filtrate. The results of this study suggest that the GDM filtration system can be considered as a potential alternative to produce POU decentralized drinking water in terms of both quantity and quality. The constant permeate flux and the complete removal of E. coli without the need for backwashing or cleaning make the technology attractive for application in developing countries to treat well water at low cost and minimum maintenance.

Significant antimicrobial-producing vegetation uniquely shapes the stormwater biofilter microbiome with implications for enhanced faecal pathogen inactivation

Biofilters demonstrate promising yet inconsistent removal of faecal pathogens from stormwater. Antimicrobial-producing plants represent safe, inexpensive biofilter design features which can significantly enhance faecal microbe treatment. The microbiota naturally inhabiting biofilters have additionally been established as key mediators of faecal microbe inactivation. To date, however, it remains unknown: (1) to what extent plants, including significant antimicrobial-producing plants, influence the biofilter microbiome; and (2) how this in turn impacts faecal microorganism survival/die-off. The present study employed 16S rRNA sequencing to examine these relationships throughout the soil profiles of differently vegetated biofilters over time. It was found that plants had subtle but significant influences on the composition and structure of resident biofilter bacterial communities, with varying impacts observed throughout biofilter profiles. Bacterial communities inhabiting biofilters comprising significant antimicrobial-producing plants demonstrated distinct compositional and taxonomic differences relative to other configurations. In particular, compared to other biofilters, the best-performing configuration for faecal bacterial treatment, Melaleuca linariifolia (significant antimicrobial-producing plant), exhibited both higher and lower relative frequencies of putative faecal bacterial antagonists (e.g. Actinobacteria) and mutualists (e.g. certain Gammaproteobacteria), respectively. These preliminary findings suggest that antimicrobial plants may enhance populations of microbiota which suppress faecal bacterial survival, and highlight the plant-microbiome relationship as a novel area of focus for optimising biofilter performance.

Stimbiotics Supplementation Promotes Growth Performance by Improving Plasma Immunoglobulin and IGF-1 Levels and Regulating Gut Microbiota Composition in Weaned Piglets.

This study was conducted to investigate the effects of dietary supplementation with stimbiotics (STB) on growth performance, diarrhoea incidence, plasma antioxidant capacity, immunoglobulin concentration and hormone levels, and faecal microorganisms in weaned piglets. Compared with the control (CT) group, the addition of STB improved the body weight (BW) of piglets on days 28 and 42 (p < 0.05) and increased daily weight gain and daily feed intake from days 14-28 and throughout the trial period (p < 0.05). Correspondingly, the plasma insulin-like growth factor 1 (IGF-1) level on day 42 was significantly improved by STB (p < 0.05). VistaPros (VP) group levels of immunoglobulin (Ig) A and G were significantly higher on days 14 and 42 (p < 0.05) than the CT group levels. In addition, the activity of plasma catalase tended to be increased on day 14 (p = 0.053) in the VP group, as for superoxide dismutase, glutathione peroxidase, and malondialdehyde, STB did not significantly affect their levels (p > 0.05). Moreover, dietary STB increased the relative abundance of beneficial bacteria, including norank_f_Muribaculaceae, Rikenellaceae_RC9_gut_group, Parabacteroides, and unclassified_f__Oscillospiraceae. In summary, STB improved the immunity and IGF-1 levels in the plasma of weaned piglets and consequently promoted the growth performance of weaned piglets.

Water Quality, Toxicity and Diversity of Planktonic and Benthic Cyanobacteria in Pristine Ancient Lake Khubsugul (Hövsgöl), Mongolia.

For the first time, microcystin-producing cyanobacteria have been detected in Khubsugul, which is ancient, pristine and one of the world's largest lakes. The microcystin synthetase genes belonged to the genera Nostoc, Microcystis and possibly Snowella spp. No microcystins were found in the water of the lake. Using the HPLC-HRMS/TOF, five microcystin congeners were identified in biofilms from stony substrates sampled in the coastal zone. The concentration of microcystins in biofilms was low: 41.95 µg g-1 d. wt. by ELISA and 55.8 µg g-1 d. wt. using HPLC. The taxonomic composition of planktonic and benthic cyanobacterial communities was determined by means of microscopy and high-throughput sequencing of 16S rDNA amplicons. Nostocales cyanobacteria dominated benthos of Lake Khubsugul and Synechococcales-plankton. The abundance of cyanobacteria was low both in plankton and benthos; there was no mass development of cyanobacteria. Hydrochemical and microbiological analyses showed that the water in the lake was clean; the number of faecal microorganisms was significantly below the acceptable guideline values. Hydrochemical and hydrophysical parameters, and the concentration of chlorophyll a, were low and within the range of values recorded in the 1970s to 1990s, and corresponded to the oligotrophic state of the lake. There were no signs of anthropogenic eutrophication of the lake and no conditions for the cyanobacterial blooms.

Hands Are Frequently Contaminated with Fecal Bacteria and Enteric Pathogens Globally: A Systematic Review and Meta-analysis

Enteric pathogen infections are a leading cause of morbidity and mortality globally, with the highest disease burden in low-income countries. Hands act as intermediaries in enteric pathogen transmission, transferring enteric pathogens between people and the environment through contact with fomites, food, water, and soil. In this study, we conducted a systematic review of prevalence and concentrations of fecal indicator microorganisms (i.e., E. coli, fecal coliform) and enteric pathogens on hands. We identified 84 studies, reporting 35,440 observations of hand contamination of people in community or household settings. The studies investigated 44 unique microorganisms, of which the most commonly reported indicators were E. coli and fecal coliforms. Hand contamination with 12 unique enteric pathogens was reported, with adenovirus and norovirus as the most frequent. Mean E. coli prevalence on hands was 62% [95% CI 40%–82%] and mean fecal coliform prevalence was 66% [95% CI 22%–100%]. Hands were more likely to be contaminated with E. coli in low/lower-middle-income countries (prevalence: 69% [95% CI 48%–88%]) than in upper-middle/high-income countries (6% [95% CI 2%–12%]). The Review also highlights the importance of standardizing hand sampling methods, as hand rinsing was associated with greater fecal contamination compared to other sampling methods.

Effect of Turning Frequency on the Survival of Fecal Indicator Microorganisms during Aerobic Composting of Fecal Sludge with Sawdust.

The study investigated the effect of turning frequency on survival of fecal indicator pathogens (E. coli, Enterococcus spp., Salmonella spp. and helminth eggs) during fecal sludge (FS) co-composting with sawdust. Dewatered FS was mixed with sawdust and composted on a pilot scale using different turning frequencies-i.e., 3 days (3TF), 7 days (7TF), and 14 days (14TF). Composting piles were monitored weekly for survival of fecal indicator microorganisms and evolution of selected physical and chemical characteristics for 14 weeks. Our results show that turning frequency has a statistically significant (p < 0.05) effect on pathogen inactivation in FS compost. The 3TF piles exhibited shorter pathogen inactivation periods (8 weeks) than 7TF and 14TF piles (10 weeks). Temperature-time was found to be the major factor responsible for the survival of pathogens in FS composting piles, followed by indigenous microbial activities and toxic by-products (monitored as NH4+-N). Our study findings suggest that even at low composting temperatures, the high turning frequency can enhance pathogen inactivation. This is a significant finding for composting activities in some rural areas where suitable organic solid waste for co-composting with FS to attain the recommended high thermophilic conditions could be greatly lacking.

Effect of Turning Frequency on the Survival of Fecal Indicator Microorganisms during Aerobic Composting of Fecal Sludge with Sawdust

Effect of Turning Frequency on the Survival of Fecal Indicator Microorganisms during Aerobic Composting of Fecal Sludge with Sawdust

Detection of faecal bacteria and antibiotic resistance genes in biofilms attached to plastics from human-impacted coastal areas

Plastics have been proposed as vectors of bacteria as they act as a substrate for biofilms. In this study, we evaluated the abundance of faecal and marine bacteria and antibiotic resistance genes (ARGs) from biofilms adhered to marine plastics. Floating plastics and plastics from sediments were collected in coastal areas impacted by human faecal pollution in the northwestern Mediterranean Sea. Culture and/or molecular methods were used to quantify faecal indicators (E. coli, Enterococci and crAssphage), and the ARGs sulI, tetW and blaTEM and the 16S rRNA were detected by qPCR assays. Pseudomonas and Vibrio species and heterotrophic marine bacteria were also analysed via culture-based methods. Results showed that, plastic particles covered by bacterial biofilms, primarily consisted of marine bacteria including Vibrio spp. Some floating plastics had a low concentration of viable E. coli and Enterococci (42% and 67% of the plastics respectively). Considering the median area of the plastics, we detected an average of 68 cfu E. coli per item, while a higher concentration of E. coli was detected on individual plastic items, when compared with 100 ml of the surrounding water. Using qPCR, we quantified higher values of faecal indicators which included inactive and dead microorganisms, detecting up to 2.6 × 102 gc mm−2. The ARGs were detected in 67–88% of the floating plastics and in 29–57% of the sediment plastics with a concentration of up to 6.7 × 102 gc mm−2. Furthermore, enrichment of these genes was observed in biofilms compared with the surrounding water. These results show that floating plastics act as a conduit for both the attachment and transport of faecal microorganisms. In contrast, low presence of faecal indicators was detected in plastic from seafloor sediments. Therefore, although in low concentrations, faecal bacteria, and potential pathogens, were identified in marine plastics, further suggesting plastics act as a reservoir of pathogens and ARGs.

Effects of dietary supplementation with bioactive peptides derived from rapeseed protein on the growth performance, serum biochemistryand faecal micro-organism composition of weaned piglets.

The present study investigated the effects of supplementing bioactive peptides derived from rapeseed protein (rapeseed peptide, Rsp) on the growth performance, serum biochemistryand faecal micro-organism composition of weaned piglets. Sixty Duroc × Landrace × Yorkshire weaned piglets of similar weights were randomly divided into three groups. The control group (NC) was fed a basal diet, and the two treatment groups, Rsp-1 and Rsp-2, were fed a basal diet supplemented with 1% or 2% Rsp, respectively, for 28 days. Each treatment consisted of five replicates with four piglets per replicate. The results showed that Rsp treatment significantly improved the average daily gain and had a better feed-to-gain ratio (p < 0.05). The diarrhoea incidence and indices of Rsp-1 and Rsp-2 groups were significantly lower than the NC group (p < 0.05), and the effect of Rsp-2 on reducing the incidence of diarrhoea was significantly higher than that of Rsp-1 (p < 0.05). The serum albumin, serum immunoglobulin Aand catalase levels of the Rsp-1 and Rsp-2 groups were significantly better than the NC group (p < 0.05). Additionally, Rsp treatment significantly gained the relative abundance of faecal Lactobacillaceae and decreased the relative abundance of faecal Eubacterium_coprostanoligenes_group, Treponemaand Coprococcus (p < 0.05). In summary, Rsp supplementation improved the growth performance, ameliorated the diarrhoea, enhanced the immune and antioxidant functionsand changed the composition of faecal micro-organisms in piglets. These findings indicate that Rsp positively affected the health of weaned piglets.

Dynamic Monitoring of Changes in Fecal Flora of Giant Pandas in Mice: Co-Occurrence Network Reconstruction.

Giant pandas are uniquely vulnerable mammals in western China. It is important to develop an animal model to explore the intestinal flora of giant pandas to understand the relationship between digestive diseases and flora. Existing animal models of intestinal flora focus on human flora-associated animals, such as mice, and there is a very limited amount of knowledge regarding giant panda flora-associated animals. To fill this gap, fecal microorganisms from giant pandas were transplanted into pseudosterile and germfree mice using single and multiple gavages. Fecal samples were collected from mice at four time points after transplantation for microbial community analysis. We determined that compared to pseudosterile mice, the characteristics of intestinal flora in pandas were better reproduced in germfree mice. There was no significant difference in microbial diversity between germfree mice and giant panda gut microbes from day 3 to day 21. Germfree mice at the phylum level possessed large amounts of Firmicutes and Proteobacteria, and at the genus level, Escherichia-Shigella, Clostridium sensu stricto 1, and Streptococcus dominated the intestinal flora structure. The microbial community co-occurrence network based on indicator species indicated that germfree mice transplanted with fecal bacteria tended to form a microbial community co-occurrence network similar to that of giant pandas, while pseudosterile mice tended to restore the microbial community co-occurrence network originally present in these mice. Our data are helpful for the study of giant panda flora-associated animals and provide new insights for the in vitro study of giant panda intestinal flora. IMPORTANCE The giant panda is a unique vulnerable mammal in western China, and its main cause of death is digestive system diseases regardless of whether these animals are in the wild or in captivity. The relationship between the intestinal flora and the host exerts a significant impact on the nutrition and health of the giant pandas. However, the protected status of the giant panda has made in vivo, repeatable, and large-sample sampling studies of their intestinal flora difficult. This greatly hinders the research depth of the giant panda intestinal flora from the source. The development and utilization of specific animal models to simulate the structure and characteristics of the intestinal flora provide another means to deal with these research limitations. However, current research examining giant panda flora-associated animals is limited. This study is the first to reveal dynamic changes in the fecal flora of giant pandas in mice after transplantation.