Gut Microorganisms Research Articles

Koji amazake produced by double saccharification contains more isomaltose and modifies the gut microbiota in mice

Koji amazake, which is made from rice and rice koji (a product of Aspergillus oryzae), is a traditional Japanese beverage that has glucose as its main component. It also contains isomaltose, which has been reported to have various functionalities related to gut health. In the present study, we attempted to produce amazake with a higher concentration of isomaltose without using any additives by focusing on the saccharification step of rice koji production as a means of creating new value for amazake. Two types of rice koji that were obtained at different fermentation time points were used, and we changed the saccharification process from the usual one step of saccharification to two steps of saccharification using a different type of rice koji for each step. The amazake made by double saccharification (DSA) contained 20 times more isomaltose than the commercial amazake products. In an in vivo study, oral administration of the DSA modified the cecal microbiota in mice. Moreover, changes were seen in the abundances of several gut microorganisms, such as Anaerotignum lactatifermentans, Muribaculum intestinale, and Parabacteroides merdae. These findings indicate that our novel method may be useful for producing amazake with a high isomaltose content that may have health benefits in humans.

Mediterranean Diet and Olive Oil Redox Interactions on Lactate Dehydrogenase Mediated by Gut Oscillibacter in Patients with Long-COVID-19 Syndrome

Chronic viral inflammation is associated with oxidative stress and changes in gut microbiota. The Mediterranean diet (MD), with recognized anti-inflammatory and antioxidant properties, modulates gut microorganisms, specifically on the interaction between extra virgin olive oil, a key component of the MD with well-documented antioxidant effects. This study investigated the influence of adherence to MD and antioxidant-rich foods (extra virgin olive oil) on biochemical, inflammatory, and microbiota profiles in patients with chronic inflammation defined as a prolonged inflammatory response due to immune dysregulation following the acute phase of the viral infection. Participants were classified into low (n = 54) and high (n = 134) MD adherence groups (cut-off of 7 points based on previous studies utilizing the same threshold in the assessment of MD adherence). Gut microbiota was sequenced using the 16S technique, and the adherence to MD was assessed using a validated questionnaire for a Spanish population. High adherence to the MD was linked to significant improvements in inflammatory and oxidative stress markers, including reductions in LDL-cholesterol, glucose, and lactate dehydrogenase (LDH) levels, an indicative of redox balance, as well as a significant higher consumption of antioxidant foods. Moreover, gut microbiota analysis revealed distinct compositional shifts and a lower abundance of the Oscillibacter genus in the high adherence group. Notably, a significant interaction was observed between MD adherence and extra virgin olive oil consumption, with Oscillibacter abundance influencing LDH levels, suggesting that the MD antioxidant properties may modulate inflammation through gut microbiota-mediated mechanisms. These findings provide new evidence that adherence to the Mediterranean diet can reduce inflammatory markers in patients with long-COVID-19, a population that has not been extensively studied, while also highlighting the potential role of the bacterial genus Oscillibacter in modulating this effect.

A new approach to biotransformation and value of kitchen waste oil driven by gut microorganisms in Hermetia illucens

Hermetia illucens larvae are known for their ability to recycle organic waste, but their capacity to recover waste oils and the role of gut microorganisms in this process are not fully understood. To gain further insights, the biological recovery of waste frying oil into valuable lipids and the influence of gut bacteria on this biotransformation were investigated. The larvae efficiently digested and absorbed waste frying oil, demonstrating their potential for converting various oils into insect fat. The presence of different fatty acids in their diet significantly altered gut bacterial communities, enriching certain genera such as Actinomyces, Enterococcus, and Providencia. Redundancy analysis revealed that the composition and structure of these bacterial communities were predictive of their function in the biotransformation of fatty acids and the lipid biosynthesis in the larvae. Specific bacteria, including Corynebacterium_1, Providencia, Actinomyces, Escherichia-Shigella, and others, were identified to play specialized roles in the digestion and absorption of fatty acids, contributing to lipid synthesis and storage. These findings highlight the potential of Hermetia illucens in the biological recovery of waste frying oil and underscore the crucial role of gut microbiota in this process, offering a sustainable approach to waste management and bioenergy production.

Mice colonized with the defined microbial community OMM19.1 are susceptible to Clostridioides difficile infection without prior antibiotic treatment.

Diverse gut microorganisms present in humans and mice are essential for the prevention of microbial pathogen colonization. However, antibiotic-induced dysbiosis of the gut microbiome reduces microbial diversity and allows Clostridioides difficile (C. difficile) to colonize the intestine. The Oligo-Mouse-Microbiota 19.1 (OMM19.1) is a synthetic community that consists of bacteria that are taxonomically and functionally designed to mimic the specific pathogen-free mouse gut microbiota. Here, we examined the susceptibility of OMM19.1 colonized mice to C. difficile infection (CDI) at a range of infectious doses (103, 105, and 107 spores) without prior antibiotic treatment. We found that mice colonized with OMM19.1 were susceptible to CDI regardless of the dose. The clinical scores increased with increasing C. difficile dosage. Infection with C. difficile was correlated with a significant increase in Ligilactobacillus murinus and Escherichia coli, while the relative abundance of Bacteroides caecimuris, Akkermansia muciniphila, Extibacter muris, and Turicimonas muris was significantly decreased following CDI. Our results demonstrate that the OMM19.1 community requires additional bacteria to enable C. difficile colonization resistance.IMPORTANCEThe human gut microbiota consists of a wide range of microorganisms whose composition and function vary according to their location and have a significant impact on health and disease. The ability to generate and test the defined microbiota within gnotobiotic animal models is essential for determining the mechanisms responsible for colonization resistance. The exact mechanism(s) by which healthy microbiota prevents Clostridioides difficile infection is unknown, although competition for nutrients, active antagonism, production of inhibitory metabolites (such as secondary bile acids), and microbial manipulation of the immune system are all thought to play a role. Here, we colonized germ-free C57BL/6 mice with a synthetic bacterial community (OMM19.1) that mimics the specific pathogen-free mouse microbiota. Following breeding, to enable immune system development, F1 mice were infected with three different doses of C. difficile. Our research suggests that there are additional essential microbial functions that are absent from the current OMM19.1 model.

Staphylea bumalda Alleviates Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice by Regulating Inflammatory Cytokines, Oxidative Stress, and Maintaining Gut Homeostasis

Staphylea bumalda is a rare medicine and edible shrub native to the temperate regions of Asia, possessing significant medicinal potential. In this study, the components of S. bumalda tender leaves and buds extract (SBE) were analyzed and identified by HPLC and LC/MS method, and the safety of SBE was evaluated through mouse acute toxicity models. The protective effects of SBE on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice were investigated in terms of inflammatory factor levels, oxidative stress, and gut microorganisms. Results showed that hyperoside, kaempferol-3-O-rutinoside, isorhoifolin, and rutin were the main components of the extract, and SBE demonstrated good safety in experimental mice. SBE could alleviate weight losing, disease activity index (DAI) raising, and colon shortening in mice. Pathological section results showed that the inflammatory cell infiltration decreased significantly, and the number of goblet cells increased significantly in the SBE group. After SBE treatment, interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) levels in serum were significantly decreased, and the levels of myeloperoxidase (MPO) and nitric oxide (NO) in colon tissues were significantly decreased. SBE inhibited gut inflammation by increasing Lactobacillus. In summary, SBE played a therapeutic role in UC mice by relieving colon injury, reducing inflammatory factor levels, and maintaining gut flora homeostasis. SBE is expected to become an auxiliary means to participate in the prevention and treatment of UC.

Essential Oils, Chemical Compounds, and Their Effects on the Gut Microorganisms and Broiler Chicken Production: Review

The influence of essential oils (EOs) on gut microorganisms and broiler chicken production was evaluated through the systematic analysis of scientific reports. The present study was focused on the EO antimicrobial activity oriented toward broiler chicken production. There is a great biodiversity of plants, and various compounds with different biological activity have been isolated from them. The EO molecules extracted from plants have been employed recently in livestock feeding. Microbial resistance to antibiotics has led to their reduced use in animal production. To maintain competitive broiler chicken production with reduced antibiotic use, EOs have been explored. In broiler chickens, EOs are supplemented in the diet or drinking water to enhance weight gain and feed efficiency and reduce mortality. EOs are an alternative to antibiotics, and their research is dynamic in poultry production. The present review focused on the antimicrobial activity oriented to broiler chicken production. The search for information in databases used the terms “broiler chicken”, “essential oils” and combined them with the name of the plants. It was detected that the EO of Cinnamon bark or its compound cinnamaldehyde could reduce pathogenic bacteria in the digestive tract and improve intestinal morphology. Essential oils from Cymbopogon spp. and Origanum vulgare had an effect mainly against Gram-negative bacteria, such as Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella spp., and others, and against some Gram-positive bacteria, such as Staphylococcus spp., or yeasts, such as Candida albicans. Essential oils of Cymbopogon citratus acted against Salmonella. Citrus japonica affected Bacillus subtilis, Escherichia coli, and Salmonella typhimurium. Origanum EO improved the antioxidant status and gut health of chickens, while EO of Eucalyptus with carvacrol, thymol, and Citrus lemon improved the productive performance of broiler chickens; also, Citrus spp. reduced the number of oocysts of Eimeria and showed activity against Listeria monocytogenes, Staphylococcus aureus, and Pseudomonas aeruginosa. It is concluded that EOs are a sustainable alternative to antibiotics in the production of broiler chickens. Future research includes the standardization of EO from different plants and active molecules, as well as the interaction with other feed additives and their impact on the health and production of broiler chickens. In addition, safety for consumers and the environment must be considered.

Rola mikrobioty jelit i jej metabolitów w przebiegu otyłości i cukrzycy

The gut microbiota is an indispensable component of the proper functioning of the human body, as gut microorganisms and their metabolites strongly influence the host's metabolism and immune functions. They also contribute to the biosynthesis of vitamins, production of gut hormones, maintenance of intestinal barrier integrity, protection against pathogens, as well as digestion and absorption of nutrients. Increasingly, the relationship between disturbances in the composition of gut microbiota and the onset of metabolic diseases such as obesity and type 2 diabetes is being emphasized. Understanding the significance of the microbiota in the course of these diseases, its composition, and activity may offer new approaches to their treatment. Increasing attention is being paid to individual species of gut bacteria, among which Akkermansia muciniphila holds a special position, as a decrease in the abundance of this commensal bacterium in the gut is associated with many diseases, including obesity and diabetes.

Time-Resolved Multiomics Illustrates Host and Gut Microbe Interactions during Salmonella Infection.

Salmonella infection, also known as Salmonellosis, is one of the most common food-borne illnesses. Salmonella infection can trigger host defensive functions, including an inflammatory response. The provoked-host inflammatory response has a significant impact on the bacterial population in the gut. In addition, Salmonella competes with other gut microorganisms for survival and growth within the host. Compositional and functional alterations in gut bacteria occur because of the host immunological response and competition between Salmonella and the gut microbiome. Host variation and the inherent complexity of the gut microbial community make understanding commensal and pathogen interactions particularly difficult during a Salmonella infection. Here, we present metabolomics and lipidomics analyses along with the 16S rRNA sequence analysis, revealing a comprehensive view of the metabolic interactions between the host and gut microbiota during Salmonella infection in a CBA/J mouse model. We found that different metabolic pathways were altered over the four investigated time points of Salmonella infection (days -2, +2, +6, and +13). Furthermore, metatranscriptomics analysis integrated with metabolomics and lipidomics analysis facilitated an understanding of the heterogeneous response of mice, depending on the degree of dysbiosis.

Response of earthworm enzyme activity and gut microbial functional diversity to carbendazim in the manured soil.

The effect of pesticide pollution on environmental microorganisms in soil has become the focus of widespread concern in society today. The response of earthworm gut and surrounding soil microbial functional diversity and enzyme activity to carbendazim (CBD) was studied in a soil-earthworm ecosystem amended with manure. In the experiment, CBD was added to the manured soil (MS). Meanwhile, the pesticide treatment without manure and the control treatment without pesticides were also set up. The activities of catalase (CAT) and acetylcholinesterase (AChE) were measured to evaluate the toxicity of CBD. The Biolog method was used to assess the functional diversity of the microbial community. In the 2 mg/kg CBD treatment, earthworm AChE activity decreased significantly in the MS after 14 d, which occurred earlier than in the un-manured soil (NS). The changes of earthworm CAT activity in the pesticide treatments showed a trend of initially increasing and then maintaining at a high activity level. However, the CAT activities at 28 d in the manured soils were clearly lower than that at 7 d for both the CBD treatments, while they remained stable in the control treatments. The carbon source utilization, Simpson index, Shannon index, and McIntosh index of soil microorganisms in the MS treatments were significantly higher than those in the NS treatments. The overall activity of earthworm gut microorganisms in the MS treated with 2 mg/kg CBD was higher than that in the control. Also, CBD treatment (2 mg/kg) increased significantly the Simpson index and McIntosh index of earthworm gut microorganisms. The results indicated that the enzyme activities in the manured soils increased before 7 d for the pesticide treatments. Furthermore, exposure to CBD at a high concentration in the MS not only led to the earlier inhibition of earthworm enzyme activity but also significantly improved the overall activity of earthworm gut microorganisms and microbial functional diversity. This study revealed the ecotoxicological effects of earthworms in response to pesticide stress following the use of organic fertilizers under facility environmental conditions, which can provide a theoretical basis for the remediation of pesticide pollution in soil in the future.

Quantitative Synthesis of Microbe-Driven Acclimation and Adaptation in Wild Vertebrates.

Microorganisms associated with animals harbour a unique set of functional traits pivotal for the normal functioning of their hosts. This realisation has led researchers to hypothesise that animal-associated microbial communities may boost the capacity of their hosts to acclimatise and adapt to environmental changes, two eco-evolutionary processes with significant applied relevance. Aiming to assess the importance of microorganisms for wild vertebrate conservation, we conducted a quantitative systematic review to evaluate the scientific evidence for the contribution of gut microorganisms to the acclimation and adaptation capacity of wild vertebrate hosts. After screening 1974 publications, we scrutinised the 109 studies that met the inclusion criteria based on 10 metrics encompassing study design, methodology and reproducibility. We found that the studies published so far were not able to resolve the contribution of gut microorganisms due to insufficient study design and research methods for addressing the hypothesis. Our findings underscore the limited application to date of microbiome knowledge in vertebrate conservation and management, highlighting the need for a paradigm shift in research approaches. Considering these results, we advocate for a shift from observational studies to experimental manipulations, where fitness or related indicators are measured, coupled with an update in molecular techniques used to analyse microbial functions. In addition, closer collaboration with conservation managers and practitioners from the inception of the project is needed to encourage meaningful application of microbiome knowledge in adaptive wildlife conservation management.

Research Progress on the Correlation between Gut Microorganisms and Gastrointestinal Diseases

The intestinal microbiota refers to the complex community of microorganisms present in the human digestive tract. With the development of high-throughput sequencing technologies such as 16SrRNA gene sequencing and metagenomic sequencing, the intestinal microbiota has been shown to be closely related to gastric cancer and colorectal cancer. At the same time, a series of studies have been conducted to explore the intestinal microbiota as a new type of non-invasive biological marker. This article summarizes the research on the intestinal microbiota of gastric cancer and colorectal cancer, and explains the changes in the intestinal microbiota when the disease occurs, so as to provide new ideas for finding potential molecular targets for the prevention, treatment, and intervention of tumors.

Rearing of Black Soldier Fly Larvae with Corn Straw and the Assistance of Gut Microorganisms in Digesting Corn Straw.

Corn straw is considered a renewable biomass energy source, and its unreasonable disposal leads to resource waste and environmental pollution. Black soldier fly (Hermetia illucens L.) larvae (BSFL) facilitate the bioconversion of various types of organic wastes. In this study, we found that 88% of BSFL survived, and 37.4% of corn straw was digested after 14 days of feeding with corn straw. Contrary to expectations, the pretreatment of corn straw with alkaline hydrogen peroxide did not promote its digestion but rather reduced the growth and survival rates of BSFL. Acinetobacter, Dysgonomonas, and unclassified Enterobacteriaceae were the abundant genera in the BSFL gut fed with corn straw. Compared with the standard diet, the relative abundances of carbohydrate metabolism genes, such as the gene abundances of β-glucosidase and α-glucosidase, were higher with corn straw as the substrate. These results suggested that the gut microbial community could regulate suitable and functional microorganisms in response to the substrates. Furthermore, four cellulase-producing strains, namely Klebsiella pneumoniae, Proteus mirabilis, Klebsiella oxytoca, and Providencia rettgeri, were isolated from the guts of corn straw BSFL. These four strains helped increase the conversion rates of corn straw, the weights of BSFL, and survival rates. In summary, we reared BSFL with corn straw and discovered the functions of gut microorganisms in adapting to the substrates. We also isolated four cellulase-producing strains from the BSFL guts and declared the benefits of BSFL digesting corn straw.

Microbiome as an endocrine organ and its relationship with eye diseases: Effective factors and new targeted approaches.

Microbiome is an endocrine organ that refers to both the complicated biological system of microbial species that colonize our bodies and their genomes and surroundings. Recent studies confirm the connection between the microbiome and eye diseases, which are involved in the pathogenesis of eye diseases, including age-related macular disorders, diabetic retinopathy, glaucoma, retinitis pigmentosa, dry eye, and uveitis. The aim of this review is to investigate the microbiome in relation to eye health. First, a brief introduction of the characteristics of the gut microorganisms terms of composition and work, the role of dysbiosis, the gut microbiome and the eye microbiome in the progression of eye illnesses are highlighted, then the relationship among the microbiome and the function of the immune system and eye diseases, the role of inflammation and aging and the immune system, It has been reviewed and finally, the control and treatment goals of microbiome and eye diseases, the role of food factors and supplements, biotherapy and antibiotics in relation to microbiome and eye health have been reviewed.

Radiation protection of sodium alginate and its regulatory effect on intestinal microflora in mice

Prolonged or high-dose exposure to ionizing radiation (IR) can cause damage to normal tissues of the body. Therefore, it is imperative to find effective radiation protective agents to mitigate IR-induced damage. This study evaluated the effects of sodium alginate (SA) on the radiation protection and modulatory effects of gut microorganisms using a 60Coγ-induced damage model in mice. Results showed that SA could reduce the damage of hematopoietic system; and alleviate the oxidative damage in irradiated mice by inhibiting the content of malondialdehyde (MDA) and increasing the activities of superoxide dismutase (SOD) and glutathione (GSH) in serum, spleen, jejunum and liver. Moreover, SA treatment ameliorated IR-induced small intestine lesions and alleviated liver injury. This was consistent with decreased levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor-α (TNF-α), and increased levels of interferon-γ (IFN-γ) and interleukin-2 (IL-2) after SA treatment. Furthermore, SA treatment reversed IR-induced gut dysbiosis, elevated the Firmicutes/Bacteroidetes ratio, increased the beneficial bacteria and reduced the pathogenic bacteria in the small intestine. In conclusion, the present study demonstrated that SA exerted good radioprotective effect by improving hematopoietic system, alleviating oxidative stress, attenuating liver injury and inflammatory response, and modulating the intestinal microbiota in irradiated mice.

Lactobacilli Cell-Free Supernatants Modulate Inflammation and Oxidative Stress in Human Microglia via NRF2-SOD1 Signaling

Microglia are macrophage cells residing in the brain, where they exert a key role in neuronal protection. Through the gut–brain axis, metabolites produced by gut commensal microbes can influence brain functions, including microglial activity. The nuclear factor erythroid 2-related factor 2 (NRF2) is a key regulator of the oxidative stress response in microglia, controlling the expression of cytoprotective genes. Lactobacilli-derived cell-free supernatants (CFSs) are postbiotics that have shown antioxidant and immunomodulatory effects in several in vitro and in vivo studies. This study aimed to explore the effects of lactobacilli CFSs on modulating microglial responses against oxidative stress and inflammation. HMC3 microglia were exposed to lipopolysaccaride (LPS), as an inflammatory trigger, before and after administration of CFSs from three human gut probiotic species. The NRF2 nuclear protein activation and the expression of NRF2-controlled antioxidant genes were investigated by immunoassay and quantitative RT-PCR, respectively. Furthermore, the level of pro- and anti-inflammatory cytokines was evaluated by immunoassay. All CFSs induced a significant increase of NRF2 nuclear activity in basal conditions and upon inflammation. The transcription of antioxidant genes, namely heme oxygenase 1, superoxide dismutase (SOD), glutathione-S transferase, glutathione peroxidase, and catalase also increased, especially after inflammatory stimulus. Besides, higher SOD1 activity was detected relative to inflamed microglia. In addition, CFSs pre-treatment of microglia attenuated pro-inflammatory TNF-α levels while increasing anti-inflammatory IL-10 levels. These findings confirmed that gut microorganisms’ metabolites can play a relevant role in adjuvating the microglia cellular response against neuroinflammation and oxidative stress, which are known to cause neurodegenerative diseases.Graphical Gut-brain crosstalk: molecular point of view. Metabolites contained in the supernatant derived from Lactobacilli can cross the gut barrier and reach the central nervous system, where they are taken up by microglial cells. They induce the activation of the NRF2 pathway and the production of inflammatory mediators. This interaction attenuates two important events: oxidation (with high levels of NRF2) and inflammation (with high levels of IL-10 and low levels of TNF-α).

The gut microbiota in thrombosis.

The gut microbiota has emerged as an environmental risk factor that affects thrombotic phenotypes in several cardiovascular diseases. Evidence includes the identification of marker species by sequencing studies of the gut microbiomes of patients with thrombotic disease, the influence of antithrombotic therapies on gut microbial diversity, and preclinical studies in mouse models of thrombosis that have demonstrated the functional effects of the gut microbiota on vascular inflammatory phenotypes and thrombus formation. In addition to impaired gut barrier function promoting low-grade inflammation, gut microbiota-derived metabolites have been shown to act on vascular cell types and promote thrombus formation. Therefore, these meta-organismal pathways that link the metabolic capacities of gut microorganisms with host immune functions have emerged as potential diagnostic markers and novel drug targets. In this Review, we discuss the link between the gut microbiota, its metabolites and thromboembolic diseases.

Geographical, Seasonal, and Growth-Related Dynamics of Gut Microbiota in a Grapevine Pest, Apolygus spinolae (Heteroptera: Miridae)

A number of insects are associated with gut symbiotic microorganisms, wherein symbiotic partners play pivotal metabolic roles for each other such as nutrient supplementation, diet degradation, and pesticide detoxification. Despite the ecological and evolutionary importance of gut microbial communities in insects, their diversity and dynamics remain unclear in many species. The green plant bug Apolygus spinolae, a notorious grapevine pest in Japan, damages grape shoots and severely reduces grape berry yield and quality. The plant bug possesses a simple tubular gut housing ~ 104 bacteria. Here, we investigated geographic, seasonal, and growth-related dynamics of gut microbiota by high-throughput sequencing in 82 individuals (11 nymphs and 71 adults) from five locations in Hokkaido, Japan. In plant bugs, gut microbiota changed dynamically depending on region, season, and developmental stage. Among the gut bacteria, Serratia was consistently and abundantly detected and was significantly affected by seasonal changes. In addition, Caballeronia, known as a specific symbiont in some stinkbug species, was abundantly detected, especially in insects collected in late summer despite A. spinolae complete lack of midgut crypts known as symbiotic organ harboring Caballeronia in other stinkbug species. Considering their prevalence among host bug populations, it is possible these gut microorganisms play a pivotal role in the adaptation of the green plant bug to grapevine fields, although further confirmation through rearing experiments is needed.

The Gut Microbiota Mediates the Protective Effects of Spironolactone on Myocardial Infarction.

Myocardial infarction (MI) is a type of cardiovascular disease that influences millions of human beings worldwide and has a great rate of mortality and morbidity. Spironolactone has been used as a critical drug for the treatment of cardiac failure and it ameliorates cardiac dysfunction post-MI. Despite these findings, whether there is a relationship between the therapeutic effects of spironolactone and the gut microorganism after MI has not been determined. In our research, we used male C57BL/6J mice to explore whether the gut microbiota mediates the beneficial function of spironolactone after myocardial infarction. We demonstrated that deletion of the gut microbiota eliminated the beneficial function of spironolactone in MI mice, displaying exacerbated cardiac dysfunction, cardiac infarct size. In addition, the gut microbiota was altered by spironolactone after sham or MI operation in mice. We also used male C57BL/6J mice to investigate the function of a probiotic in the myocardial infarction. In summary, our findings reveal a precious role of the gut flora in the therapeutic function of spironolactone on MI.

Deeper insight into the storage time of food waste on black soldier fly larvae growth and nutritive value: Interactions of substrate and gut microorganisms

Biological treatment of food waste (FW) by black soldier fly larvae (BSFL) is considered as an effective management strategy. The composition and concentrations of nutrients in FW change during its storage and transport period, which potentially affect the FW conversion and BSFL growth. The present study systematically investigated the effect of different storage times (i.e., 0–15 d) on FW characteristics and its substantial influence on the BSFL growth. Results showed that the highest larvae weight of 282 mg and the shortest growth time of 14 days were achieved at the group of FW stored for 15 days, but shorter storage time (i.e., 2–7 d) had adverse effect on BSFL growth. Short storage time (i.e., 2–4 d) improved protein content of BSFL biomass and prolonged storage time (i.e., 7–10 d) led to the accumulation of fat content. The changes of substrate characteristics and indigenous microorganisms via FW storage time were the main reasons for BSFL growth difference. Lactic acid (LA) accumulation (i.e., 19.84 g/L) in FW storage for 7 days significantly limited the BSFL growth, leading to lowest larvae weight. Both the substrate and BSFL gut contained same bacterial communities (e.g., Klebsiella and Proteus), which exhibited similar change trend with the prolonged storage time. The transfer of Clostridioides from substrate to BSFL gut promoted nutrients digestion and intestinal flora balance with the FW stored for 15 days. Pathogens (e.g., Acinetobacter) in BSFL gut feeding with FW storage time of 7 days led to the decreased digestive function, consistent with the lowest larvae weight. Overall, shorter storage time (i.e., 2–7 d) inhibited the BSFL digestive function and growth performance, while the balance of the substrate nutrients and intestinal flora promoted the BSFL growth when using the FW stored for 15 days.

Mice colonized with the defined microbial community OMM19.1 are susceptible to C. difficile infection without prior antibiotic treatment.

Diverse gut microorganisms present in humans and mice are essential for the prevention of microbial pathogen colonization. However, antibiotic-induced dysbiosis of the gut microbiome reduces microbial diversity and allows C. difficile to colonize the intestine. The Oligo Mouse Microbiota 19.1 (OMM19.1) is a synthetic community that consists of bacteria that are taxonomically and functionally designed to mimic the specific pathogen-free (SPF) mouse gut microbiota. Here, we examined the susceptibility of OMM19.1 colonized mice to C. difficile infection at a range of infectious doses (10 3 , 10 5 , and 10 7 spores) without prior antibiotic treatment. We found that mice colonized with OMM19.1 were susceptible to C. difficile infection regardless of the dose. The clinical scores increased with increasing C. difficile dosage. Infection with C. difficile was correlated with a significant increase in Ligilactobacillus murinus and Escherichia coli , while the abundance of Bacteroides caecimuris, Akkermansia muciniphila, Extibacter muris, and Turicimonas muris significantly decreased following C. difficile infection. Our results demonstrate that the OMM19.1 community requires additional bacteria to enable colonization resistance.