Saccharomyces cerevisiae SC-2201 Attenuates AOM/DSS-Induced Colorectal Cancer by Modulating the Gut Microbiome and Blocking Proinflammatory Mediators.

Colorectal cancer is the third most common cancer in the world today, and studies have shown that the ratio of Candida to Saccharomyces cerevisiae increased, and the abundance of S. cerevisiae in the intestines of patients with colorectal cancer decreased, which suggests that there is an imbalance in the proportion of fungi in the intestines of patients with colorectal cancer. The objective of this study was to screen S. cerevisiae isolate from traditional Chinese fermentation starters and assess its ability to ameliorate dysbiosis and to alleviate the carcinogenic process of azoxymethane/dextran sodium sulfate-induced colorectal cancer in mice model. S. cerevisiae strain SC-2201 was isolated and exhibited probiotic properties, including the ability to survive in an acidic pH environment and in the presence of bile salts in the gastrointestinal tract, as well as antioxidant activities. Oral administration of S. cerevisiae SC-2201 not only alleviated weight loss but also reduced colonic shortening and histological damage in azoxymethane/dextran sodium sulfate-induced colorectal cancer in mice. Furthermore, the administration of S. cerevisiae SC-2201 suppressed the expression of proinflammatory mediators, such as interleukin-1ß, interleukin-6, cyclooxygenase-2, vascular endothelial growth factor, nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing protein 3. Specifically, the analysis of gut bacteriome showed a significant decrease in Bacteroidota and Campylobacterota levels, as well as an increase in Proteobacteria level in the colorectal cancer group, which was alleviated by supplementation with S. cerevisiae SC-2201. The analysis of the mycobiome revealed a significant increase in the levels of Basidiomycota, Apiosordaria, Naganishia, and Taphrina genera in the colorectal cancer group, which were alleviated after supplementation with S. cerevisiae SC-2201. However, the levels of Xenoramularia, Entoloma, and Keissleriella were significantly increased after administration with S. cerevisiae SC-2201. Overall, the findings of this study demonstrate that S. cerevisiae SC-2201 possesses potential probiotic properties and can effectively attenuate the development of colorectal cancer, highlighting its cancer-preventive potential. This is the first report of a S. cerevisiae strain isolated from traditional Chinese fermentation starters which showed good probiotic properties, and mitigated azoxymethane/dextran sodium sulfate-induced colorectal cancer by modulating the gut microbiome and blocking proinflammatory mediators in mice.

Contralesional Anodal Transcranial Direct Current Stimulation Promotes Intact Corticospinal Tract Axonal Sprouting and Functional Recovery After Traumatic Brain Injury in Mice.

BACKGROUND: Anodal transcranial direct current stimulation (AtDCS), a neuromodulatory technique, has been applied to treat traumatic brain injury (TBI) in patients and was reported to promote functional improvement. We evaluated the effect of contralesional AtDCS on axonal sprouting of the intact corticospinal tract (CST) and the underlying mechanism in a TBI mouse model to provide more preclinical evidence for the use of AtDCS to treat TBI. METHODS: TBI was induced in mice by a contusion device. Then, the mice were subjected to contralesional AtDCS 5 days per week followed by a 2-day interval for 7 weeks. After AtDCS, motor function was evaluated by the irregular ladder walking, narrow beam walking, and open field tests. CST sprouting was assessed by anterograde and retrograde labeling of corticospinal neurons (CSNs), and the effect of AtDCS was further validated by pharmacogenetic inhibition of axonal sprouting using clozapine-N-oxide (CNO). RESULTS: TBI resulted in damage to the ipsilesional cortex, while the contralesional CST remained intact. AtDCS improved the skilled motor functions of the impaired hindlimb in TBI mice by promoting CST axon sprouting, specifically from the intact hemicord to the denervated hemicord. Furthermore, electrical stimulation of CSNs significantly increased the excitability of neurons and thus activated the mechanistic target of rapamycin (mTOR) pathway. CONCLUSIONS: Contralesional AtDCS improved skilled motor following TBI, partly by promoting axonal sprouting through increased neuronal activity and thus activation of the mTOR pathway.

Ultrasmall Cu2O@His Nanozymes with RONS Scavenging Capability for Anti-inflammatory Therapy.

High concentrations of reactive oxygen and nitrogen species (RONS) are key characteristics of inflammatory sites. Scavenging RONS at the site of inflammation is an effective therapeutic strategy. This study introduces ultrasmall Cu2O@His nanoparticles with RONS-scavenging ability for the treatment of inflammatory bowel disease (IBD) in mice. The strong coordination between the nitrogen atom in histidine (His) and copper enhances the dispersion and stability of Cu2O@His. Due to their small size and large surface area, Cu2O@His exhibits outstanding RONS-clearing ability. Importantly, Cu2O@His can target mitochondrial sites and repair damaged mitochondria. With excellent dispersion and scavenging RONS ability, Cu2O@His demonstrates good efficacy in treating mouse IBD. This work provides a new paradigm for developing nanozymes with an ultrasmall size and multiple scavenging RONS abilities.

Alcohol degradation, learning, and memory-enhancing effect of Acetobacter pasteurianus BP2201 in Caenorhabditis elegans model.

AIMS: This study aimed to investigate the probiotic effects of Acetobacter pasteurianus BP2201, isolated from brewing mass, for the treatment of alcohol-induced learning and memory ability impairments in a Caenorhabditis elegans model. METHODS AND RESULTS: Acetobacter pasteurianus BP2201 was examined for probiotic properties, including acid and bile salt resistance, ethanol degradation, antioxidant efficacy, hemolytic activity, and susceptibility to antibiotics. The strain displayed robust acid and bile salt tolerance, efficient ethanol degradation, potent antioxidant activity, and susceptibility to specific antibiotics. Additionally, in the C. elegans model, administering A. pasteurianus BP2201 significantly improved alcohol-induced learning and memory impairments. CONCLUSIONS: Acetobacter pasteurianus BP2201 proves to be a promising candidate strain for the treatment of learning and memory impairments induced by alcohol intake.

Fusobacterium nucleatum and its metabolite hydrogen sulfide alter gut microbiota composition and autophagy process and promote colorectal cancer progression.

IMPORTANCE: Colorectal cancer (CRC) is the second most common cancer in the world; the main treatment for CRC is immunosuppressive therapy, but this therapy is only effective for a small percentage of CRC patients, so there is an urgent need for a treatment with fewer side effects and higher efficacy. This study demonstrated that Fusobacterium nucleatum with increased abundance in CRC can regulate the autophagy process and disrupt normal intestinal microbiota by producing hydrogen sulfide, factors that may be involved in the development and progression of CRC. This study may provide a reference for future CRC treatment options that are efficient and have fewer side effects.

Synthetic microbial consortia for the treatment of Clostridioides difficile infection in mice model.

Clostridioides difficile infection (CDI) as of recent has become a great concern to the impact on human health due to its high hazardous risk and rate of recurrence. Live bacterial therapeutics is a promising method to treat or prevent CDI. Here, a synthetic microbial consortia (SMC) B10 was constructed using probiotic strains with antibacterial and anti-quorum sensing activities, and the therapeutic effect of SMC B10 against C. difficile infection was evaluated in vitro. Compared to the model group, the treatment of SMC B10 significantly increased the survival rate. The clinical signs of mice were significantly ameliorated, especially the cecum injury, while the secretion of pro-inflammatory associated cytokines such as IL-1α, IL-6, IL-17A and TNF-α was reduced, the expression of TLR4 was inhibited, which alleviated the inflammatory response, and the expression of the tight junction protein Claudin-1 was increased, ultimately promoting the recovery of host health. The treatment of B10 restored gut microbiota dysbiosis and led to a healthy intestinal microbiota structure, significantly improved alpha diversity, suppressing potentially harmful bacteria and restoring other core bacterial species. In conclusion, SMC B10 can effectively treat CDI through modulate gut microbiota and attenuate the inflammatory response.

Acetobacter pasteurianus BP2201 alleviates alcohol-induced hepatic and neuro-toxicity and modulate gut microbiota in mice.

The excessive consumption of alcohol results in a dysbiosis of the gut microbiota, which subsequently impairs the gut microbiota-brain/liver axes and induces cognitive dysfunction and hepatic injury. This study aimed to investigate the potential effect of Acetobacter pasteurianus BP2201 in reducing the negative effects of alcohol consumption on cognitive function and liver health by modulating the gut microbiota-brain/liver axes. Treatment with A. pasteurianus BP2201 improved alcohol-induced hippocampal damage, suppressed neuroinflammation, promoted neuroprotein expression in the hippocampus and enhanced cognitive function. At the same time, A. pasteurianus BP2201 can also reduce serum lipid levels, relieve oxidative stress, inhibit TLR4/MyD88/NF-κB pathway, reduce the secretion of TNF-α and IL-1ß, so as to improve alcoholic liver injury. Concomitantly, the treatment with A. pasteurianus BP2201 leads to a shift in the intestinal microbiota structure towards that of healthy individuals, inhibiting the proliferation of harmful bacteria and promoting the recovery of beneficial bacteria. In addition, it also improves brain cognitive dysfunction and liver health by affecting the gut microbiota-brain/liver axes by promoting the synthesis of relevant amino acids and the metabolism of nucleotide base components. These findings demonstrate the potential of regulating the gut microbiome and gut microbiota-brain/liver axes to mitigate alcohol-induced disease.

Characterization of Cetobacterium somerae CPU-CS01 isolated from the intestine of healthy crucian carp (Carassius auratus) as potential probiotics against Aeromonas hydrophila infection.

Cetobacterium somerae is a commensal bacterium for many fish species. However, research on C. somerae has been limited so far, and its function and beneficial potential require to be further investigated. The objective of this study was to evaluate the probiotic properties of C. somerae CPU-CS01 isolated from the intestinal contents of crucian carp (Carassius auratus). Hemolytic activity, antibiotic susceptibility, acid tolerance, bile salt tolerance, free radical scavenging, and enzyme production properties were tested for in vitro. Caenorhabditis elegans and zebrafish (Danio rerio) model were used to evaluate the antioxidant and anti-infective effects of C. somerae CPU-CS01 in vivo. Our results showed that C. somerae CPU-CS01 had no hemolytic activity, it produced cellulase, amylase, and survived at low pH (2.0-3.0) and in the presence of bile salts. The cell-free culture supernatant (CFCS) of C. somerae CPU-CS01 possessed DPPH radical, hydroxyl radical, and superoxide anion scavenging activity. C. elegans fed with C. somerae CPU-CS01 were more resistant to hydrogen peroxide-induced oxidative stress and Aeromonas hydrophila infection. In addition, zebrafish-fed diets containing C. somerae CPU-CS01 showed improved survival after A. hydrophila infection. Based on these results, the positive probiotic properties of C. somerae CPU-CS01 isolated from the intestinal contents of crucian carp make it a potential candidate for probiotic.

Synthetic bacterial consortia transplantation for the treatment of Gardnerella vaginalis-induced bacterial vaginosis in mice.

Bacterial vaginosis (BV) is a disease caused by vaginal microbiota dysbiosis. Here, we propose the use of synthetic bacterial consortia transplantation (SBCT) for the treatment of Gardnerella vaginalis-induced BV mice. The results showed that SBCT significantly reduced vaginal tissue damage and restored the vaginal microbiota, decreased the secretion of pro-inflammatory cytokines (IL-1ß and IL-8), and suppressed NF-κB activation. IL-17, iNOS, and COX-2 expression in vaginal tissue were also down-regulated. However, IL-10 and Foxp3 showed up-regulated expression in mice. Compared with vaginal microbiota transplantation (VMT), results indicated that VMT was more effective than SBCT in suppressing G. vaginalis-induced inflammation. The obtained results suggest that synthetic bacterial consortia might be used as a potential biotherapeutic agent for the treatment of G. vaginalis-induced bacterial vaginosis. Video Abstract.

Lactobacillus salivarius CPU-01 Ameliorates Temozolomide-Induced Intestinal Mucositis by Modulating Gut Microbiota, Maintaining Intestinal Barrier, and Blocking Pro-inflammatory Cytokines.

Chemotherapy-induced intestinal mucositis is one of the major toxic side effects in the treatment of cancer patients. The purpose of this study is to screen lactic acid bacteria which could alleviate intestinal inflammation and damage induced by chemotherapeutic agents and explore the possible underlying mechanisms. Lactobacillus salivarius CPU-01 was selected from traditional Chinese fermented foods due to its protective effects on the toxicity of temozolomide in Caenorhabditis elegans. Eighteen ICR mice were randomly divided into 3 groups including control group, temozolomide-induced intestinal mucositis group, and temozolomide + L. salivarius CPU-01 group, and were used to investigate the effect of L. salivarius CPU-01 on chemotherapy-induced intestinal mucositis. It has been demonstrated that the administration of L. salivarius CPU-01 can prevent colon shortening and alleviate colon tissue damage caused by temozolomide-induced intestinal mucositis in mice. L. salivarius CPU-01 relieved the intestinal microbiota disorders caused by temozolomide and contributed to the growth of beneficial bacteria, such as Lactobacillus, Clostridia UCG - 014_norank, and Akkermansia. In vivo experiments also indicated that L. salivarius CPU-01 can suppress the level of temozolomide-induced pro-inflammatory cytokines in serum and mRNA expression in the small intestine tissues. It was also found that L. salivarius CPU-01 significantly increased the expressions of intestinal tight junction (TJ) proteins, ZO-1, and Occludin proteins in mice treated with temozolomide. These findings suggest that L. salivarius CPU-01 can ameliorate temozolomide-induced intestinal mucositis by modulating gut microbiota, blocking pro-inflammatory cytokines, and repairing the intestinal barrier. These findings suggest probiotics may serve as a potential alternative therapeutic strategy for the prevention of chemotherapy-induced intestinal mucositis in the future.

ß-sitosterol inhibits trimethylamine production by regulating the gut microbiota and attenuates atherosclerosis in ApoE-/- mice.

The intestinal microbial metabolite trimethylamine (TMA), which is activated by flavin monooxygenase (FMO) to produce trimethylamine-N-oxide (TMAO), has been implicated in the pathogenesis of atherosclerosis (AS), leading to the development of therapeutic strategies for AS. This study aimed to investigate whether ß-sitosterol can inhibit TMA production in ApoE-/- mice by reshaping the gut microbial structure. 16S rRNA sequencing of the gut microbiota showed that ß-sitosterol has beneficial effects on intestinal flora function, especially the inhibition of bacteria genera that contain the gene cholintrimethylamine lyase, which is responsible for the major pathway for TMA production. In parallel, ß-sitosterol effectively reduced the TMA, FMO3, and TMAO levels while ameliorating the atherosclerotic plaques of AS mice. Moreover, ß-sitosterol could alleviate cholesterol metabolism and the inflammatory response, and improve the antioxidant defense capacity. These studies offer new insights into the mechanisms responsible for the antiatherosclerotic effects of ß-sitosterol, which targets the microbiota-metabolism-immunity axis as a possible therapy for AS.

Synthesis and Evaluation of Antioxidant and Potential Prebiotic Activities of Acetylated and Butyrylated Fructo-Oligosaccharides.

Fructo-oligosaccharides (FOS) have well-known bifidogenic effects as probiotics. In this study, esterification was adopted for FOS modification to produce better prebiotic properties. We synthesized and characterized acetylated fructo-oligosaccharides (Ac-FOS) and butyrylated fructo-oligosaccharides (Bu-FOS) as candidate prebiotics. Antioxidant activity and prebiotic esactiviti were evaluated as important indicators. We found, surprisingly, that butyrylation was an effective method in significantly improving the antioxidant activity of FOS. The fermentation products of feces from mice added to Ac-FOS and Bu-FOS, were investigated in vitro, including changes of pH values, short-chain fatty acids (SCFAs) production, and microbiota composition. Supplementation of Ac-FOS or Bu-FOS increased pH values and promoted the growth and activity of beneficial intestinal bacteria, such as Bifidobacteria and Lactobacillus. More importantly, the levels of prebiotic SCFAs were obviously elevated as detected by Gas Chromatography-Mass Spectrometry (GC-MS). Results suggest that Ac-FOS and Bu-FOS have great potential applications in SCFA delivery systems and gut microbiota regulation.

Gypenoside XLIX Ameliorate High-Fat Diet-Induced Atherosclerosis via Regulating Intestinal Microbiota, Alleviating Inflammatory Response and Restraining Oxidative Stress in ApoE-/- Mice.

A high-fat choline diet (HFCD)-induced atherosclerosis model in ApoE-/- mice was established to explore the anti-atherosclerotic effects of gypenoside XLIX (GPE). It was found that HFCD-induced atherosclerotic index such as dyslipidemia, atherosclerotic plaque, inflammation, and gut microbiota dysfunction could be reduced by GPE treatment. GPE treatment could decrease Verrucomicrobia, Proteobacteria, and Actinobacteria abundance, and increase Firmicutes and Bacteroidetes population. Moreover, the Firmicutes/Bacteroidetes ratio increased significantly after treatment with GPE. After treatment with GPE, the relative abundance of trimethylamine-producing intestinal bacteria Clostridioides and Desulfovibrionaceae decreased while butyrate-producing bacteria such as Eubacterium, Roseburia, Bifidobacterium, Lactobacillus, and Prevotella increased significantly. The GPE group demonstrated higher SCFAs concentrations in the fecal sample, such as Acetic Acid, Propionic Acid, and Butyric Acid. Further pathway analysis showed that 29 metabolic pathways were appreciably disturbed during GPE treatment, including citrate cycle (TCA cycle); galactose and glycero-lipid-metabolism biosynthesis of unsaturated fatty acids, fatty acid biosynthesis. This study suggests that the anti-atherosclerotic effect of GPE is related to the substantial changes in intestinal microbiota and anti-inflammatory activity.

Gut Microbiota and Inflammatory Cytokine Changes in Patients with Ankylosing Spondylitis.

Ankylosing spondylitis (AS) is a chronic inflammatory disease characterized by sacroiliac joint lesions and spinal ascending involvement. The aim of this work was at investigating the gut microbiota profile and proinflammatory cytokines in AS patients. Gut microbiota of AS patients was clearly different from that of healthy human controls. 16S rRNA sequencing analysis demonstrated a changed microbial diversity in the AS patients, and there was a significant increase in the abundance of Cyanobacteria, Deinococcota, Patescibacteria, Actinobacteriota, and Synergistota at a phyla level increased in AS, while the relative abundance of Acidobacteriota, Bdellovibrionota, Campylobacterota, Chloroflexi, Gemmatimonadota, Myxococcota, Nitrospirota, Proteobacteria, and Verrucomicrobiota declined in AS patients. ELISA results for the markers of inflammation in the AS patients revealed increased concentrations of proinflammatory cytokines such as IL-23, IL-17, and IFN-γ. Our findings support the fact that the intestinal microbiota are altered in AS with an inflammatory status, which indicates that gut microbiota should be a potential target for ankylosing spondylitis therapy.

A Sensitive Visual Method for the Detection of Hydrogen Sulfide Producing Bacteria.

Hydrogen sulfide (H2S) is a toxic gas produced by bacteria in the proteolysis of sulfur-containing amino acids and proteins that plays an important role in human health. The H2S production test is one of the important bacterial biochemical identification tests. The traditional methods are not only tedious and time-consuming but also prone to inhibition of bacterial growth due to the toxic effect of heavy metal salts in sulfur-containing medium, which often leads to negative results. Here, we established a simple and sensitive method to detect H2S in bacteria. This method is a modified version of bismuth sulfide (BS) precipitation that uses 96-well transparent microtiter plates. Bacterial culture was combined with bismuth solution containing L-cysteine and cultivated for 20 min, at the end of which a black precipitate was observed.The visual detection limit for H2S was 0.2 mM. Based on the visual color change, the simple, high-throughput, and rapid detection of H2S producing bacteria can be achieved. In summary, this method can be used to identify H2S production in bacteria.

Evaluation of Antioxidative and Neuroprotective Activities of Total Flavonoids From Sea Buckthorn (Hippophae rhamnoides L.).

The aim of this study was to investigate the antioxidative and neuroprotective activities of total flavonoids from sea buckthorn (Hippophae rhamnoides L.) (TFH). Results indicated that TFH possessed DPPH radicals, hydroxyl radicals and superoxide anions scavenging activities. The neuroprotective potential was assessed with acetylcholinesterase (AChE) and monoamine oxidase A (MAO-A). The inhibition rates of AChE and MAO-A by 50 µg/ml TFH were 75.85 and 51.22%, respectively. The in vivo antioxidative and neuroprotective potential of TFH were explored in Caenorhabditis elegans. In the longevity assay, TFH (50 µg/ml) significantly increased the lifespan of wild-type C. elegans (29.40%). In the hydrogen peroxide-induced oxidative stress challenge, the antioxidant capacity of TFH-treated wild-type C. elegans was significantly enhanced. The C. elegans mutant strain CL4176 was used to study the neuroprotective effect of TFH in vivo. Results showed that TFH significantly delayed paralysis in C. elegans CL4176. Our study suggested total flavonoids from sea buckthorn (Hippophae rhamnoides L.) had the potential as an antioxidative and neuroprotective agent to extend aging and treat neurodegenerative diseases.

Microsurgical sealing for symptomatic sacral Tarlov cysts: a series of 265 cases.

OBJECTIVE: Tarlov cysts (TCs) are a common cystic entity in the sacral canal, with a reported prevalence between 1.5% and 13.2%; 10%-20% of patients are symptomatic and need appropriate clinical intervention. However, the choice of treatment remains controversial. The goal of this study was to describe a new microsurgical sealing technique for symptomatic sacral TCs (SSTCs) as well as its long-term outcomes. METHODS: Microsurgical sealing was performed using a short incision, leakage coverage with a piece of autologous fat, and cyst sealing with fibrin glue. Postoperative data were collected at three stages: discharge, 1-year follow-up, and a follow-up of 3 years or more. According to the improvement in neurological deficits and degree of pain relief, outcomes were divided into four levels: excellent, good, unchanged, and deteriorated. RESULTS: A total of 265 patients with SSTCs were treated with microsurgical sealing from January 2003 to December 2020. The mean follow-up was 44.69 months. The percentages of patients who benefited from the operation (excellent and good) at the three stages were 87.55%, 84.89%, and 80.73%, respectively, while those who received no benefit (unchanged and deteriorated) were 12.45%, 15.11%, and 19.27%, respectively. Of the patients with postoperative MRI, the cysts were reduced in size or disappeared in 209 patients (94.14%). CSF leakage from the wound was observed in 15 patients, and 4 patients experienced an infection at the incision. There were no cases of new-onset nerve injury or aseptic meningitis after the operation. CONCLUSIONS: SSTC patients undergoing microsurgical sealing had persistently high rates of symptom relief and few postoperative complications. Microsurgical sealing is an effective, simple, and low-risk method for treating SSTCs.

Exploring of probiotic potential vaginal lactobacillus isolates from healthy women against Gardnerella vaginalis and Caenorhabditis elegans model testing.

AIM: Lactobacillus species are the dominant microorganisms in the vaginal microbiota of healthy women and play an important role in the defence against pathogens. This study aimed to evaluate probiotic potential of Lactiplantibacillus plantarum strain P1 isolated from healthy woman's vaginal discharge for its further utilization as a promising candidate strain in the treatment of bacterial vaginosis caused by Gardnerella vaginalis. METHODS AND RESULTS: Ten lactobacilli strains from a woman's vaginal discharge were evaluated for their probiotic potential, including growth capacity at different pH levels (pH 3.5-4.5), acid production, hydrogen peroxide production capacity, antibacterial activity and susceptibility to antibiotics. Moreover, in vitro safety assay haemolytic activity and mutagenicity were investigated for safety assessment. In vivo Caenorhabditis elegans infection model was used to investigate the anti-infection effect of selected isolates. We found that lactobacilli strain P1 showed strong growth ability in low acid environment, produced acid, hydrogen peroxide, had the strongest antibacterial activity against G. vaginalis and was highly susceptible to the tested antibiotics. When assayed for the safety, strain P1 showed no haemolytic activity and had no effect of mutagenicity. Moreover, P1 significantly increased the lifespan of C. elegans against G. vaginalis infection. Combined with the results of 16S rRNA gene sequencing, morphological and physiological characteristic, the strain was identified as Lactiplantibacillus plantarum. CONCLUSION: Lactiplantibacillus plantarum strain P1 proves to be a promising candidate strain in the treatment of bacterial vaginosis caused by G. vaginalis. SIGNIFICANCE AND IMPACT OF THE STUDY: Conventional antibiotic therapy for bacterial vaginosis has led to the accelerated process of bacterial drug resistance. Probiotics are potentially an alternative method for bacterial vaginosis therapy. This finding provides bacterial resources for keeping pathogens away from the vagina. We believe L. plantarum P1 may be used as vaginal probiotics and be useful to prevent or treat bacterial vaginitis.

Visualizing Bacterial Motility Based on a Color Reaction.

Bacterial motility is crucial for bacterial pathogenicity, biofilm formation, and drug resistance. Bacterial motility is crucial for the invasion and/or dissemination of many pathogenic species. Therefore, it is important to detect bacterial motility. Bacterial growth conditions, such as oxygen, pH, and temperature, can affect bacterial growth and the expression of bacterial flagella. This can lead to reduced motility or even loss of motility, resulting in the inaccurate evaluation of bacterial motility. Based on the color reaction of 2,3,5-triphenyl tetrazolium chloride (TTC) by intracellular dehydrogenases of living bacteria, TTC was added to traditional semisolid agar for bacterial motility detection. The results showed that this TTC semisolid agar method for the detection of bacterial motility is simple, easy to operate, and does not involve large and expensive instruments. The results also showed that the highest motility was observed in semisolid medium prepared with 0.3% agar. Compared with the traditional semisolid medium, the results are easier to evaluate and more accurate.