Gorbach et al. In reported cases of gas gangrene, C. In a review of cases of clostridial bacteremia in cancer patients by Bodey et al. While the exact underlying pathogenesis of C. In our case, the diagnosis was made through blood cultures obtained prior to empiric treatment with intravenous piperacillin-tazobactam and vancomycin.
The success of the treatment of established gas gangrene in clinical practice has depended largely upon early diagnosis and prompt surgical intervention as means to control the source of infection. Urgent, thorough surgical debridement is mandatory to improve survival, preserve limbs, and prevent complications [ 12 ]. Several types of antibiotics, including penicillin, clindamycin, rifampin, metronidazole, chloramphenicol, tetracycline, and erythromycin have been shown to be effective in vitro or in animal studies.
Historically in humans, penicillin G has been recommended in doses of between 10 and 24 million units per day. Currently, a combination of penicillin and clindamycin is widely used for treating clostridial gas gangrene.
The rationale for using penicillin in combination with clindamycin is that some strains of Clostridium are resistant to clindamycin but susceptible to penicillin. Clindamycin is thought to be the superior drug for reducing toxin formation [ 18 ].
Other, non-clostridial bacteria are frequently found in gas gangrene tissue cultures, so treatment that is active against Gram-positive e. Use of multiple drugs active against anaerobes is not necessary and puts the patients at risk for additional drug toxicities. No data or guidelines support the use of two anti-anaerobic drugs in clinical practice. In some cases, double anaerobic coverage is preferred by many clinicians, for example metronidazole can be added to another agent with anaerobic activity when being used to treat clostridium difficile infection.
Another situation is clindamycin which can be added to another agent with anaerobic activity when being used for the treatment of necrotizing fasciitis [ 19 ]. Even in the case of single agents that cover all 3 categories of bacteria, eg, broad-spectrum penicillins Dual antibiotic therapy is recommended for all necrotizing soft-tissue infections given observed synergism in animal models [ 20 ].
First line treatment of confirmed C. In a study performed by Roberts et al. This recommendation, along with any form of medical treatment, was refused by the patient, who expired within a few days of treatment cessation. Clostridium sporogenes is a rare clinical pathogen and thus its discovery as the bacteremic agent in an immunocompetent patient made this case an unusual one. As with any patient suspected of being septic, obtaining cultures and routine susceptibility tests and initiating antimicrobial therapy in a timely manner are critical for obtaining an optimal outcome.
However, without a rapid diagnostic test for Clostridium spp. Fortunately, Clostridium species remain susceptible to many antibiotics used in the treatment of bacteremia, osteomyelitis and sepsis but may not prevent progression to death. Our institution does not require ethical approval for reporting individual cases or case series. We all authors certify that we have seen and approved the final version of the manuscript being submitted. National Center for Biotechnology Information , U.
Journal List IDCases v. Published online Jan 2. Mena Shehata b Joan C. Zeynep Koc b Joan C. Author information Article notes Copyright and License information Disclaimer. Waiel Abusnina: ude. Published by Elsevier Ltd. This indicates a lack of nuclei in the region, suggesting that the cells in this region were necrotic Fig. The spheroids were exposed to IB 0.
At each time point, a decrease in the cell proliferation was observed. These values are higher than the cell proliferation of cells in the 2D model exposed to the same concentration of IB.
As anticipated, the size of the control spheroids increases significantly between each time point, over the entire duration of the study. The inhibitory effect of higher concentrations of IB 0. S2 , is greater than that of 0. The effect of CM on the spheroids was investigated similarly. RCM caused a slight decrease in the cell proliferation across all time points. On the other hand, the inhibitive effect of CM is significant, with the cell proliferation of CT26 spheroids decreasing to CM induces a slight regression in the CT26 spheroids from 2.
For RCM exposed spheroids, the area, although smaller than the control, was still larger than the spheroids exposed to CM. This inhibitive effect of CM is also reflected the morphology of the spheroids Fig.
CM causes deformation of the spheroids, stunting of the spheroid size initially and then its regression. In an attempt to determine if proteins are involved in the previous observations, CM was boiled to denature the proteins and obtain boiled conditioned media BCM. By the end of the study, it was observed that BCM has a considerably lesser inhibitive effect on cell proliferation The growth of the spheroids exposed to BCM is stunted, although their shape is maintained.
Comparatively, spheroids exposed to CM regress in size and also lose their shape Fig. To further characterize the role of IB in inhibiting cancer cell growth, the morphology of the 3D spheroids was examined. It was found that the cells on the periphery of the control CT26 spheroids were circular in shape, packed together with tight cell contacts and thickly covered by the ECM.
On the other hand, on the periphery of the spheroids exposed to IB, the cells were elongated in shape, loosely packed and the ECM appeared to be thinner. The spherical morphology of the control spheroid was not observed in the IB spheroid, which appeared deformed Fig. This is in agreement with Fig. Images taken with scanning electron microscope SEM. Arrows indicate elongated cells on the surface and the white arrow indicate deformation in the shape of IB-exposed spheroids.
There exist several studies on the oncolytic effect of C. Since then, C. However, the risk of infection persisted with the application of spores or live vegetative bacteria. Therefore, this study investigated the anti-cancer effect non-viable derivatives of C.
Our findings suggest that the observed inhibitive effect on the cells can be attributed to the natural oncolytic properties of IB and CM as these bacterial derivatives cannot proliferate and do not deprive the cells of nutrition. While the inactivated forms of gram-negative Streptococcus equisimilis and Staphylococcus aureus bacteria have been studied previously by Klier et al.
This is crucial as we can then associate the effects observed to the bacterial surface proteins instead of the intracellular components. To study the effects of CM, a range of RCM concentrations, diluted in cell culture media, was examined to determine the maximum concentration that can be used without adversely affecting the cell viability.
Mammalian cells cannot grow in bacterial culture media and as expected, the RCM components affected cell viability to some extent. In the 2D model, the exposure to IB exerted a significant anti-proliferative effect on CT26 and HCT cells in a concentration-dependent manner and CM was found to also have a strong inhibitive effect on the cells.
In a study by Arimochi et al. Together with our data, this demonstrates the potential of the bacteria-free CM as an anti-cancer agent. Despite these promising results, it has been suggested in literature that cells grown in a 2D monolayer are more susceptible to drug treatment and thus not a reliable in vitro model 40 , The use of 3D spheroids in this study is important as it allows the evaluation of IB and CM as potential anti-cancer agents on a physiologically relevant platform 46 , Methods such as hanging-drop 48 and low adhesion plates 49 were tried initially to generate the 3D spheroids, but these methods were found to have limitations which affected the uniformity of the spheroids.
Later, the use of round-bottom, low-adhesion plates generated spheroids that were consistently reproduced with uniformity in both size and shape. The spheroids that were grown developed necrotic regions that simulate the hypoxic, necrotic conditions of the in vivo tumor microenvironment 47 , A 3D model is more complex as it simulates the cell-cell and cell-ECM interactions of real tumors This could be a reason why the cell proliferation rate of the CT26 spheroids exposed to 0.
In general, the cells grown in a monolayer in a 2D model are more susceptible to external treatments as compared to that of a spheroid where there is a gradient of nutrient and gas exchange with the surroundings 41 , SEM imaging was used to understand the morphological changes caused by IB in the spheroid.
It was found that the spheroid morphology was lost and the cells were loosely packed. Furthermore, in vivo studies have demonstrated that inactivated bacteria of S. Therefore, the main factor in affecting anti-proliferation of the cells was likely to be a bacterial product secreted into the culture medium.
This suggests that the bacterial proteins in CM have caused this inhibitive effect. In particular, this could be due to the extracellular proteases of C. This study has discovered that both these non-viable bacterial derivatives of C.
However, the mechanism of inhibition and the interaction between IB and cancer cells still remains to be understood. Understanding the differences between the two cell lines may help to better characterize the mechanism of inhibition.
Other studies have investigated CM and IB in different bacteria species but have not been able to elucidate the mechanism of the observed actions 38 , Earlier studies have shown that the use of bacterial components may be applied as an adjuvant to initiate anti-tumor responses Additionally, the specific components of CM that causes cancer cell inhibition has also not been identified although the data suggests that it is heat-liable in nature.
It will be important to address these unanswered questions before these bacterial derivatives can be developed into effective therapeutic agents. In conclusion, this study proves that inactivated C. After this 3 day growth period, the spheroids were used for the experiments. The C. After the supernatant was discarded, the inactivated bacterial pellet was re-suspended in complete growth media of cancer cells for use in the experiments.
The heat-inactivated C. Images were obtained using a fluorescence microscope Olympus, Japan. The spores were cultured in RCM using the same protocol as described above.
The supernatant was collected and filtered using a 0. The result is defined as conditioned media CM. The inactivated bacteria IB suspension in complete growth medium was serially diluted to concentrations of 0.
For the 3D spheroid culture, 3 day old spheroids were incubated with 0. The 3D spheroids were re-suspended into a single cell suspension. The absorbance value of each well is directly proportional to the number of viable cells.
A fluorescence microscope Olympus, Japan was used to take the fluorescence images of each well. They were then dehydrated with a series of increasing concentrations of ethanol before being embedded in paraffin. The embedded samples were sectioned to a thickness of 5. The sections were then stained with haematoxylin and eosin and imaged using a bright-field microscope. All experiments were performed in triplicate, for statistical significance.
How to cite this article : Bhave, M. Siegel, R. Cancer statistics, CA Cancer J. Article Google Scholar. Razik, R. Long-term outcomes following resection of retroperitoneal recurrence of colorectal cancer.
However, it is rarely recognized as a clinical pathogen. Less than 25 cases of infection secondary to this organism have been reported so far. In this report, we present a case of bacteremia in an immunocompetent patient, which was caused by C. A year-old man with a past medical history of Parkinson's disease was brought to the emergency department of our hospital by ambulance after he was found lying on the floor in prone position inside his house.
The patient most probably fell on the floor several days ago before he was found in this position. According to the next of kin, the patient had multiple falls in the past few months that were attributed by her to the patient's Parkinson disease. The patient did not seek medical attention for any of these episodes. On arrival in the emergency department, the patient was found to be extremely lethargic and dehydrated. On physical examination: Skin revealed the presence of multiple pressure ulcers located on his face, chest, and left leg that had developed from staying immobilized on the ground for several days.
The ulcers were covered with necrotic tissue and were unstageable. No abscess or gas gangrene was noted to be present. The patient was admitted to the medical intensive care unit MICU for eight days and was then transferred to the general medical floor, where he remained admitted for almost a month.
Initially, in MICU, the patient was found to have a high white blood cell count and fever. All three of the blood cultures were positive for Clostridium sporogenes. Then Clindamycin was added to the antibiotic regimen.
The patient showed significant improvement in his condition and completed a day course of each antibiotic. The skin debridement was postponed because of the unstable patient condition and the good response that had reached by medical management. After stabilization of the patient's condition, the patient underwent surgical debridement of the necrotic pressure ulcers. Biopsy and culture of the skin tissue were performed and did not reveal the presence of any pathogens. Members of the genus Clostridium are characterized as anaerobic, gram-positive, spore-forming rods that are found ubiquitously in soils and marine sediments, also as natural inhabitants of the gastrointestinal tract in humans and most other animals.
These bacteria are well-recognized for their ability to cause serious and rapidly fatal diseases. The development of these diseases may be due to a variety of toxigenic or invasive processes [ 1 ].
Despite the presence of Clostridium species as a part of the natural intestinal microflora and in the outside environment, infection with these organisms is not common. The water was seeded with Enterococcus faecalis, Clostridium sporogenes spores, and P22 bacteriophage, each at ca 1 x The crude antimicrobial compound is sensitive to. Ethanol production by Clostridium thermocellum grown on hydrothermally and organosolv-pretreated lignocellulosic materials.
Two strains of the thermophilic anaerobe Clostridium thermocellum, the wild type NCIB and its ethanol-hyperproductive mutant , were tested for their ability to grow on natural lignocellulosic materials poplar wood, wheat straw which had been pretreated by either hydrothermolysis or an organosolv process.
For both materials and both strains, the dependencies of substrate accessibility on the pretreatment temperature were established in terms of cellulose hydrolysis and of product formation. In addition to the non-pH-controlled shake flask assays, in vitro experiments with cell-free culture supernatant and in vivo cellulolyses under pH regulation in a laboratory fermenter indicated that lignocellulosics pretreated at approx.
Anaerobic bacteraemia revisited: species and susceptibilities. This retrospective study was performed to evaluate the frequency of anaerobic bacteraemia over a year period, and to provide updated antibiotic susceptibilities for the more clinically relevant anaerobes causing blood stream infection.
Data were retrieved from the laboratory information system for the period to A representative subset of isolates were retrieved from to and antimicrobial susceptibilities to penicillin, amoxicillin-clavulanate, clindamycin, imipenem, moxifloxacin, piperacillin-tazobactam and metronidazole were determined using the Etest method.
Anaerobes comprised 4. The only significant change in anaerobe positivity rates occurred between and , with an increase of 0. The most active in vitro antibiotics were imipenem, piperacillin-tazobactam, amoxicillin-clavulanate and metronidazole, with susceptibilities of Resistance was high to penicillin, clindamycin and moxifl oxacin.
However, there were apparent differences for antibiotic susceptibilities between species. This study indicates that the anaerobes comprise a small but constant proportion of bloodstream isolates. Mechanism of quinolone resistance in anaerobic bacteria. Several recently developed quinolones have excellent activity against a broad range of aerobic and anaerobic bacteria and are thus potential drugs for the treatment of serious anaerobic and mixed infections.
Resistance to quinolones is increasing worldwide, but is still relatively infrequent among anaerobes. Two main mechanisms, alteration of target enzymes gyrase and topoisomerase IV caused by chromosomal mutations in encoding genes, or reduced intracellular accumulation due to increased efflux of the drug, are associated with quinolone resistance.
These mechanisms have also been found in anaerobic species. High-level resistance to the newer broad-spectrum quinolones often requires stepwise mutations in target genes. The increasing emergence of resistance among anaerobes may be a consequence of previous widespread use of quinolones, which may have enriched first-step mutants in the intestinal tract.
Quinolone resistance in the Bacteroides fragilis group strains is strongly correlated with amino acid substitutions at positions 82 and 86 in GyrA equivalent to positions 83 and 87 of Escherichia coli. Several studies have indicated that B. DNA gyrase seems also to be the primary target for quinolones in Clostridium difficile, since amino acid substitutions in GyrA and GyrB have been detected in resistant strains.
To what extent other mechanisms, such as mutational events in other target genes or alterations in outer-membrane proteins, contribute to resistance among anaerobes needs to be further investigated. Occurrence and molecular characterization of cultivable mesophilic and thermophilic obligate anaerobic bacteria isolated from paper mills. The aim of this work was to characterize the cultivable obligate anaerobic bacterial population in paper mill environments.
A total of anaerobically grown bacterial isolates were screened for aerotolerance, from which 67 obligate anaerobes were characterized by automated ribotyping and 41 were further identified by partial 16S rDNA sequencing. The mesophilic isolates indicated 11 different taxa species within the genus Clostridium and the thermophilic isolates four taxa within the genus Thermoanaerobacterium and one within Thermoanaerobacter both formerly Clostridium. The most widespread mesophilic bacterium was closely related to C.
One mill was contaminated with a novel mesophilic bacterium most closely related to C. The most common thermophile was T. The genetic relationships of the mill isolates to described species indicated that most of them are potential members of new species. On the basis of identical ribotypes clay could be identified to be the contamination source of thermophilic bacteria. Automated ribotyping can be a useful tool for the identification of clostridia as soon as comprehensive identification libraries are available.
Clostridium difficile infection: molecular pathogenesis and novel therapeutics. The Gram-positive anaerobic bacterium Clostridium difficile produces toxins A and B, which can cause a spectrum of diseases from pseudomembranous colitis to C.
A limited number of C. Here, the structure and the mechanism of action of these toxins as well as their role in disease are reviewed. Nosocomial C. Metronidazole and oral vancomycin are clinically used for treatment of C. Methods for controlling both toxins and spores, replacing gut microflora by probiotics or fecal transplant, and killing bacteria in the anaerobic gut by photodynamic therapy are discussed.
Anaerobic degradation of landfill leachate using an upflow anaerobic fixed-bed reactor with microbial sulfate reduction. The reactor, which was inoculated with a mixed consortium, was operated under a constant hydraulic retention time HRT of 5 days. Under these conditions, microscopic analysis showed the abundance of vibrios and rod-shaped bacterial cells.
Two anaerobic bacteria were isolated from the reactor sludge. Phylogenetic studies performed on these strains identified strain A1 as affiliated to Clostridium genus and strain H1 as a new species of sulfate-reducing bacteria affiliated to the Desulfovibrio genus. Physiological and metabolic characterization was performed for this strain.
Proposal to restrict the genus Clostridium Prazmowski to Clostridium butyricum and related species. The genus Clostridium as presently constituted is phylogenetically and phenotypically incoherent. Data from polyphasic taxonomic studies indicate that the genus comprises a collection of very heterogeneous species. Numerous phylogenetic studies, principally based on sequencing of the 16S rRNA gene, indicate that the genus Clostridium should be restricted to Clostridium cluster I as Clostridium sensu stricto.
Despite these findings, authors continue to add novel species to the genus Clostridium that do not fall within the radiation of cluster I and the type species Clostridium butyricum , thus perpetuating the confusion associated with the taxonomy of this group.
Here, we formally propose that members of the genus Clostridium Prazmowski be restricted to the type species C.
Eubacterium moniliforme , Eubacterium tarantellae , Sarcina maxima and Sarcina ventriculi should be transferred to the genus Clostridium as Clostridium moniliforme comb.
A novel genus, Hathewaya gen. The type species of the genus Hathewaya is Hathewaya histolytica. Evaluation of the in vitro activity of levornidazole, its metabolites and comparators against clinical anaerobic bacteria.
This study evaluated the in vitro anti- anaerobic activity and spectrum of levornidazole, its metabolites and comparators against clinical isolates of anaerobic bacteria, including Gram-negative bacilli strains , Gram-negative cocci 11 strains , Gram-positive bacilli strains and Gram-positive cocci 44 strains , covering 34 species. Minimum inhibitory concentrations MICs of levornidazole, its five metabolites and three comparators against these anaerobic isolates were determined by the agar dilution method.
Minimum bactericidal concentrations MBCs of levornidazole and metronidazole were measured against 22 strains of Bacteroides fragilis. Levornidazole showed good activity against B. The activity of levornidazole and the comparators was poor for Veillonella spp. Generally, levornidazole displayed activity similar to or slightly higher than that of metronidazole, ornidazole and dextrornidazole against anaerobic Gram-negative bacilli, Gram-positive bacilli and Gram-positive cocci, especially B.
Favourable anti- anaerobic activity was also seen with levornidazole metabolites M1 and M4 but not M2, M3 or M5. For the 22 clinical B. Levornidazole is an important anti- anaerobic option in clinical settings in terms of its potent and broad-spectrum in vitro activity, bactericidal property, and the anti- anaerobic activity of its metabolites M1 and M4. Expression of a Clostridium perfringens genome-encoded putative N-acetylmuramoyl-L-alanine amidase as a potential antimicrobial to control the bacterium.
Clostridium perfringens is a Gram-positive, spore-forming anaerobic bacterium that plays a substantial role in non-foodborne human, animal and avian diseases as well as human foodborne disease. Previously discovered C. Microbiology and physiology of anaerobic fermentation of cellulose.
Annual report for , , and final report. This report focuses on the bioconversion of cellulose to methane by various anaerobes. The structure and enzymatic activity of cellulosome and polycellulosome was studied in Clostridium thermocellum. The extracellular enzymes involved in the degradation of plant material and the physiology of fermentation was investigated in anaerobic fungi.
Mutant strain of C. A biologically pure asporogenic mutant of Clostridium acetobutylicum is produced by growing sporogenic C. The mutant which as been designated C. Effects of gamma ray and electron-beam irradiations on survival of anaerobic and facultatively anaerobic bacteria. An extension of the approval for food irradiation is desired due to the increase in the incidence of food poisoning in the world.
One anaerobic Clostridium perfringens and four facultatively anaerobic Bacillus cereus, Escherichia coli OH7, Listeria monocytogenes, and Salmonella Enteritidis bacteria irradiated with gamma ray or electron beam E-beam were tested in terms of survival on agar under packaging atmosphere. Using pouch pack, effects of two irradiations on survival of anaerobic and facultatively anaerobic bacteria were evaluated comparatively.
The gamma irradiation of the bacteria without incubation at 4 deg C before irradiation was more effective than that of the bacteria with incubation overnight at 4 deg C before irradiation in decreasing the D10 values of these bacteria B. Furthermore, ground beef patties inoculated with bacteria were irradiated with 1 kGy by E-beam 5 MeV at 4 deg C.
The inoculated bacteria in the mm beef patties were killed by 1 kGy E-beam irradiation and some bacteria in more than 9 mm beef patties were not killed by the irradiation.
Background: Clostridium difficile is the most important anaerobic , gram positive, spore forming bacillus which is known as a prevalent factor leading to antibiotic associated diarrheas and is the causative agent of pseudomembrane colitis. The role of this bacterium along with the over use of antibiotics have been proved to result in colitis.
The major virulence factors of these bacteria are the A and B toxins. Objectives: The purpose of this study was to isolate C. A novel regulator controls Clostridium difficile sporulation, motility and toxin production. Clostridium difficile is an anaerobic pathogen that forms spores which promote survival in the environment and transmission to new hosts.
The regulatory pathways by which C. We identified two factors with limited similarity to the Rap sporulation proteins of other spore-forming bacteria. In this study, we show that disruption of the gene CD reduces sporulation and increases toxin production and motility.
This mutant was more virulent and exhibited increased toxin gene expression in the hamster model of infection. Based on these phenotypes, we have renamed this locus rstA, for regulator of sporulation and toxins. Our data demonstrate that RstA is a bifunctional protein that upregulates sporulation through an unidentified pathway and represses motility and toxin production by influencing sigD transcription.
Conserved RstA orthologs are present in other pathogenic and industrial Clostridium species and may represent a key regulatory protein controlling clostridial sporulation.
Initiation of sporulation in Clostridium difficile: a twist on the classic model. The formation of dormant endospores is a complex morphological process that permits long-term survival in inhospitable environments for many Gram-positive bacteria.
Sporulation for the anaerobic gastrointestinal pathogen Clostridium difficile is necessary for survival outside of the gastrointestinal tract of its host. While the developmental stages of spore formation are largely conserved among endospore-forming bacteria, the genus Clostridium appears to be missing a number of conserved regulators required for efficient sporulation in other spore-forming bacteria.
Several recent studies have discovered novel mechanisms and distinct regulatory pathways that control the initiation of sporulation and early-sporulation-specific gene expression. These differences in regulating the decision to undergo sporulation reflects the unique ecological niche and environmental conditions that C.
Antioxidant and antimicrobial effects of condiments paste used as nitrite replacer in chicken mince. The antimicrobial studies viz. Total viable count TVC, Escherichia coli count, Clostridium sporogenes count and Clostridium perfringens count were carried out on 1, 4, 7 and 10th day of storage.
Conclusion: The Ginger garlic turmeric paste has an excellent potential to replace the nitrite as a natural antioxidant with other advantages. It is highly effective against Escherichia coli. We recommend further research by replacing the nitrite with various combinations of the spices and the condiments. Epidemiology and antimicrobial susceptibilities of wound isolates of obligate anaerobes from combat casualties.
Data from recent conflicts related to war wounds and obligate anaerobes are limited. Susceptibility against eleven antibiotics 7 classes was tested. Overall, 59 patients had obligate anaerobes identified 83 were first isolates. Patients with pelvic wounds were more likely to have Bacteroides spp. Bacteroides spp. Patients with resistant isolates had similar outcomes to those with susceptible strains.
Published by Elsevier Inc. Aerobic microorganisms have been sources of medicinal agents for several decades and an impressive variety of drugs have been isolated from their cultures, studied and formulated to treat or prevent diseases.
On the other hand, anaerobes , which are believed to be the oldest life forms on earth and evolved remarkably diverse physiological functions, have largely been neglected as sources of bioactive compounds.
However, results obtained from the limited research done so far show that anaerobes are capable of producing a range of interesting bioactive compounds that can promote human health.
Anaerobes play health-promoting roles through their bioactive products as well as application of whole cells. The bioactive compounds produced by these microorganisms include antimicrobial agents and substances such as immunomodulators and vitamins.
Bacteriocins produced by anaerobes have been in use as preservatives for about 40 years. Because these substances are effective at low concentrations, encounter relatively less resistance from bacteria and are safe to use, there is a growing interest in these antimicrobial agents.
Moreover, several antibiotics have been reported from the cultures of anaerobes. Closthioamide and andrimid produced by Clostridium cellulolyticum and Pantoea agglomerans, respectively, are examples of novel antibiotics of anaerobe origin. The discovery of such novel bioactive compounds is expected to encourage further studies which can potentially lead to tapping of the antibiotic production potential of this fascinating group of microorganisms.
Anaerobes are widely used in preparation of fermented foods and beverages. During the fermentation processes, these organisms produce a number of bioactive compounds including anticancer, antihypertensive and antioxidant substances. The well-known health promoting effect of fermented food is mostly due to these.
To investigate the in vitro antimicrobial activity of silicone oil against anaerobic agents, specifically Propionibacterium acnes, Peptostreptococcus spp. Control inoculations were performed in anaerobic blood agar and fluid thioglycollate medium without silicone oil. Propionibacterium acnes retained their viability on the 3rd day in the presence of silicone oil. In total, 9. After a prolonged incubation of 7 days, the number of colonies observed was 9.
The other bacteria disappeared after the 3rd day of incubation in silicone oil. Propionibacterium acnes, which is the most common chronic postoperative endophthalmitis agent, is thought to be resistant to silicone oil.
Isolation of obligate anaerobic bacteria from ulcerative keratitis in domestic animals. To determine the frequency of obligate anaerobic bacterial isolation from corneal samples of domestic animals with ulcerative keratitis and to characterize the historical, clinical, cytological, and microbiological features of culture-positive cases.
Three hundred and thirty domestic animals with ulcerative keratitis. Anaerobic bacteriologic culture and Gram stain were performed on corneal samples from consecutive animals examined with suspect septic ulcerative keratitis.
Additional corneal diagnostics included: aerobic bacteriologic culture for all species; fungal culture for ungulates; Mycoplasma culture and virus isolation or feline herpesvirus-1 FHV-1 polymerase chain reaction PCR for cats. Historical, clinical, and cytological findings were correlated with microbiologic data. Anaerobic bacteria were isolated from The most frequent isolates were Clostridium , Peptostreptococcus, Actinomyces, Fusobacterium, and Bacteroides species. The majority of these infections were mixed anaerobic and aerobic bacteria, unless antimicrobial therapy had been administered prior to presentation.
The clinical appearance of anaerobic bacterial culture-positive cases was highly variable. Ocular trauma, pre-existing corneal disease, previous corneal surgery, and chronic dermatological disease were significantly P anaerobic cultures in one or more species.
The results of the present study demonstrate that obligate anaerobic bacteria are present within the intralesional flora of ulcerative keratitis in domestic animals. In most species evaluated, these bacteria were identified infrequently. Anaerobic bacterial infection of the cornea most frequently occurs in association with other ocular pathogens and previous corneal abnormalities.
Effect of nitrite on the microbiological stability of canned Vienna sausages preserved by mild heat treatment or combinations of heat and irradiation. Keeping quality of Vienna sausages packed in No. In uninoculated cans the heat requirement of preservation proved to be about 0. A heat treatment of 0. The effect of the combination of heat treatment of 0.
The combination of irradiation plus heat resulted in a higher microbiological stability of the samples than the reversed order of the treatments, but this synergistic effect could not be proved in all experiments. The addition of ppm NaNO 2 was not as effective in increasing the shelf-life of combination treated samples as with the solely heat treated ones.
In the range of the permitted concentration level for canned meat products, sodium nitrite did not influence the heat resistance of Clostridium sporogenes , but inhibited the germination of the surviving spores. In vitro activity of cefbuperazone, a new cephamycin, against anaerobic bacteria. The level of activity of cefbuperazone was higher against B. We evaluated the analytical performance characteristics of the Bruker Microflex with Biotyper 3.
A collection of anaerobic bacteria were evaluated, including Clostridium spp. Stress hormone epinephrine adrenaline and norepinephrine noradrenaline effects on the anaerobic bacteria. Microbial endocrinology is a relatively new research area that already encompasses the anaerobes. Stress hormones, epinephrine and norepinephrine, can affect the growth of anaerobic bacteria such as Fusobacterium nucleatum, Prevotella spp.
Epinephrine and norepinephrine effects can lead to a growth increase or decrease, or no effect on the growth of the anaerobes. The effects are species-specific and perhaps strain-specific. Discrepancies in the results of some studies can be due to the different methods and media used, catecholamine concentrations, measurement techniques and the low number of strains tested. Biological effects of the stress hormones on the anaerobes may range from halitosis and a worsening of periodontal diseases to tissue damages and atherosclerotic plaque ruptures.
Optimizations of the research methods and a detailed assessment of the catecholamine effects in conditions mimicking those in affected organs and tissues, as well as the effects on the quorum sensing and virulence of the anaerobes and the full spectrum of biological consequences of the effects are interesting topics for further evaluation. Increased activity of a new chlorofluoroquinolone, BAY y , compared with activities of ciprofloxacin, sparfloxacin, and other antimicrobial agents against anaerobic bacteria.
A total of clinical isolates of anaerobes were tested with a broth microdilution method to determine the activity of BAY y compared with those of other agents against anaerobic bacteria. All strains of Bacteroides capillosus, Prevotella spp. Risk factors for mortality resulting from anaerobic infection are incompletely defined. The clinical significance of a broad range of pathogenic obligate anaerobic organisms was examined, and factors independently associated with mortality were identified in patients with clinically significant anaerobic infections.
The medical records of 1, patients with anaerobic infections were retrospectively reviewed at Severance Hospital in Seoul, Korea. The mean age of the patients was Overall, Ten 1. The mean number of pathogens, including aerobic and anaerobic bacteria, was 3. The major pathogens by rank were the Bacteroides fragilis group, which accounted for Escherichia coli The overall crude mortality rate resulting from anaerobic infection was Anaerobic infection is polymicrobial and has a significant role in morbidity and mortality.
Underlying liver disease was associated with poor prognosis in anaerobic infection. Genome-centric metatranscriptomes and ecological roles of the active microbial populations during cellulosic biomass anaerobic digestion. Although anaerobic digestion for biogas production is used worldwide in treatment processes to recover energy from carbon-rich waste such as cellulosic biomass, the activities and interactions among the microbial populations that perform anaerobic digestion deserve further investigations, especially at the population genome level.
Metagenomics and metatranscriptomics were used to capture the active microbial populations in each enrichment culture and reconstruct their meta-metabolic network and ecological roles. Phylogenetic and functional convergence of communities by enrichment condition and phase of fermentation was observed for the highly transcribed populations in the metatranscriptomes.
While the meta-metabolism and trophic roles of the cultures were similar, the bacterial populations performing each function were distinct between the enrichment conditions. Overall, a population genome-centric view of the meta-metabolism and functional roles of key active players in anaerobic digestion of cellulosic biomass was obtained. This study represents a major step forward towards understanding the microbial functions and interactions at population genome level during the.
Utilization of steam- and explosion-decompressed aspen wood by some anaerobes. After washing, this material was also found to be suitable for the single-step conversion of cellulose to ethanol using cocultures consisting of cellylolytic and ethanol-producing saccharolytic anaerobes ; and without and after washing by the use of cellulolytic enzymes and ethanologenic anaerobes.
Strong antimicrobial activity of xanthohumol and other derivatives from hops Humulus lupulus L. Anaerobic bacteria, such as Bacteroides fragilis or Clostridium perfringens, are part of indigenous human flora. However, Clostridium difficile represents also an important causative agent of nosocomial infectious antibiotic-associated diarrhoea. Treatment of C.
Hops Humulus lupulus L. We tested antimicrobial activity of purified hop constituents humulone, lupulone and xanthohumol against anaerobic bacteria. The antimicrobial activity was established against B. All C. Our study, thus, shows a potential of purified hop compounds, especially xanthohumol, as alternatives for treatment of infections caused by select anaerobic bacteria, namely nosocomial diarrhoea caused by resistant strains.
New thermophilic anaerobes that decompose crystalline cellulose. Though strain 25A was nearly identical to Clostridium thermocellum ATCC as a reference strain, strain 3B had some characteristics different from the reference; no flagellation, alkalophilic growth property optimum pH of 7.
Strain 3B effectively decomposed micro-crystalline cellulose Avicel and raw cellulosics rice straw, newspaper, and bagasse without physical or chemical pretreatments.
Complete Genome Sequence of a thermotolerant sporogenic lactic acid bacterium, Bacillus coagulans strain 36D1. Bacillus coagulans is a ubiquitous soil bacterium that grows at C and pH 5. The ability of this sporogenic lactic acid bacterium to grow at C and pH 5.
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