Immunology of gut microbiome and liver in non-alcoholic fatty liver disease (NAFLD): mechanisms, bacteria, and novel therapeutic targets.

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world. Most important contributors to its development are diet and obesity. Gut microbiome's importance for immune system and inflammatory pathways more widely accepted as an important component in NAFLD and other liver diseases' pathogenesis. In this article we review potential mechanisms of microbiome alteration of local and systemic immune responses leading to NAFLD's development, and how can modulate them for the treatment. Our review mentions different immune system pathways and microorganisms regulating metabolism, liver inflammation and fibrosis. We specifically point out TLR-4 as a potential key immune pathway activated by bacterial lipopolysaccharides producing pro-inflammatory cytokines in NAFLD. Also, we discuss three endotoxin-producing strains (Enterobacter cloacae B29, Escherichia coli PY102, Klebsiella pneumoniae A7) that can promote NAFLD development via TLR4-dependent immune response activation in animal models and how they potentially contribute to disease progression in humans. Additionally, we discuss their other immune and non-immune mechanisms contributing to NAFLD pathogenesis. In the end we point out gut microbiome researches' future perspective in NAFLD as a potential new target for both diagnostic and treatment.

Antimicrobial activity of phytofabricated silver nanoparticles using Carica papaya L. against Gram-negative bacteria.

Background and Aim: Antibiotic resistance, especially in Gram-negative bacteria, is a major public health risk affecting all industries requiring the use of antibiotics, including agriculture and animal breeding. This study aimed to use papaya extracts to synthesize silver nanoparticles (AgNPs) and evaluate their antimicrobial activity against various Gram-negative bacteria. Materials and Methods: Silver nanoparticles were synthesized from the aqueous extracts of papaya seed, root, and bark, with AgNO3 used as a reducing agent. The phytofabricated AgNPs were analyzed by ultraviolet-visible absorbance, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy, and photon cross-correlation spectroscopy (PCCS). The disc-diffusion method was used to perform antibacterial analysis, and the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations were determined. We also investigated the antibiofilm activity of AgNPs and attempted to elucidate the potential mechanism of action on Escherichia coli ATCC 25922. Results: Phytofabrication of AgNPs was successful with papaya root (PR-AgNPs) and papaya seed (PS-AgNPs), but not with papaya bark. Silver nanoparticles using papaya root and PS-AgNPs were both cubic and showed maximum absorbances of 2.6 and 0.3 AUs at 411.6 and 416.8 nm wavelengths and average hydrodynamic diameters X50 of 59.46 ± 7.03 and 66.57 ± 8.89 nm, respectively. The Ag in both AgNPs was confirmed by X-ray fluorescence by a distinctive peak in the spectrum at the silver Kα line of 22.105 keV. Both AgNPs exhibited broad-spectrum antimicrobial and antibiofilm activity against all Gram-negative bacteria, and PR-AgNPs were slightly better than AgNPs-PS. The MIC ranged from 16 µg/mL-128 µg/mL and 16 µg/mL-64 µg/mL, respectively, for PS-AgNPs and PR-AgNPs. The elucidation of the mechanism of action revealed interference with E. coli ATCC 25922 growth kinetics and inhibition of H+-ATPase proton pumps. Conclusion: Papaya seed and root extracts were efficient reducing agents for the biogenic synthesis of AgNPs, with noteworthy antibacterial and antibiofilm activities. Future studies should be conducted to identify the phytochemicals and the mechanism involved in AgNPs synthesis.

Antifungal activity of silver nanoparticles prepared using Aloe vera extract against Candida albicans.

Background and Aim: Resistance to antifungal agents is a serious public health concern that has not been investigated enough because most studies on antimicrobials are dedicated to antibacterial resistance. This study aimed to synthesize silver nanoparticles (AgNPs) using Aloe vera extract, and to assess its antifungal activity against Candida albicans. Materials and Methods: Silver nanoparticles were synthesized by reducing Ag nitrate with aqueous A. vera extracts. Physicochemical properties of synthesized AgNPs were determined by ultraviolet-visible spectrophotometry, photon cross-correlation spectroscopy, energy-dispersive X-ray fluorescence spectrometry, X-ray diffraction analysis, and Fourier-transform infrared spectroscopy. An antifungal investigation was performed against four clinical C. albicans (C1, C2, C3, and C4) and a reference strain, C. albicans ATCC 10321. Results: Cubic AgNPs with a mean X50 hydrodynamic diameter of 80.31 ± 10.03 nm were successfully synthesized. These AgNPs exhibited maximum absorbance at 429.83 nm, and X-ray fluorescence (XRF) confirmed the presence of Ag in AgNPs solution by a characteristic peak in the spectrum at the Ag Kα line of 22.105 keV. Infrared spectra for AgNPs and A. vera extract indicated that the compounds present in the extract play an essential role in the coating/capping of synthesized AgNPs. Different concentrations (200, 100, 50, 25, 10, and 5 µg/mL) of AgNPs were tested. The antifungal activity was shown to be dose-dependent with inhibition zones ranging from 10 mm to 22 mm against C. albicans ATCC 10231, 0 mm to 15 mm against C1, 0 mm to 16 mm against C2 and C3, and 0 mm to 14 mm for C4. Minimum inhibitory concentration ranged from 16 µg/mL to 32 µg/mL against clinical C. albicans (C1, C2, C3, and C4) and was 4 µg/mL against C. albicans ATCC 10231. Conclusion: This study showed the ability of A. vera to serve as an efficient reducing agent for the biogenic synthesis of AgNPs with excellent antifungal activity.

Irrigation in Endodontics: Polyhexanide Is a Promising Antibacterial Polymer in Root Canal Treatment.

BACKGROUND: chronic apical periodontitis is a common pathology in dentistry, especially in endodontics. It is necessary to systematize data concerning commonly used irrigation solutions. The development of new protocols for endodontic treatment is a very promising direction. The use of a polyhexanide-based antiseptic can positively affect the results of endodontic treatment. METHODS: the review was carried out involving the search for English language research and meta-analyses in the Google Scholar and PubMed databases. RESULTS: the number of literary sources that were identified during the literature review is 180. After excluding publications that did not match the search criteria, the total number of articles included in the systematic review was determined to be 68. CONCLUSIONS: polyhexanide is a promising solution for infected root canal irrigation. The antibacterial activity of this substance is suitable for the elimination of pathogens responsible for the appearance of apical periodontitis.

Antimicrobial and Antibiotic-Resistance Reversal Activity of Some Medicinal Plants from Cameroon against Selected Resistant and Non-Resistant Uropathogenic Bacteria.

BACKGROUND AND AIM: Antibiotics' resistance is the leading cause of complications in the treatment of urinary tract infections. This study aimed to screen the antimicrobial potential of 8 plants from Cameroon against multi-resistant uropathogenic (MRU) bacteria and to investigate their antibioresistance reversal properties. METHOD: Bioactive compounds were extracted from leaves of Leucanthemum vulgare, Cymbopogon citratus, Moringa oleifera and Vernonia amygdalina; barks of Cinchona officinalis and Enantia chlorantha barks and seeds of Garcinia lucida and leaves and seeds of Azadirachta indica using water and ethanol as solvents. The extracts were tested against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538 and Candida albicans 10231 using the well diffusion and the broth microdilution methods. The antibiotic-resistance reversal activity was assessed against selected MRU bacteria. The phytochemical composition and the elemental composition of the most active extracts were assessed respectively using HPLC-MS/MS and X-ray fluorescence (XRF) spectrometry. RESULTS: Among the most active plants, in decreasing order of antimicrobial activity we found ethanolic (EE) and aqueous extracts (AE) of E. chloranta bark (ECB), EE of L. vulgare leaves and G. lucida seeds. The best synergies between common antibiotics and extracts were found with EE-ECB which well-modulated kanamycin nitrofurantoin and ampicillin. All the compounds identified in EE-ECB were alkaloids and the major constituents were palmatine (51.63%), columbamine+7,8-dihydro-8-hydroxypalmatine (19.21%), jatrorrhizine (11.02%) and pseudocolumbamine (6.33%). Among the minerals found in EE-ECB (S, Si, Cl, K, Ca, Mn, Fe, Zn and Br), Br, Fe and Cl were the most abundant with mean fluorescence intensities of 4.6529, 3.4854 and 2.5942 cps/uA respectively. CONCLUSIONS: The ethanol extract of the bark of E. chlorantha has remarkable, broad-spectrum antimicrobial and contains several palmatine derivatives.

In vitro antimicrobial activity, antibioresistance reversal properties, and toxicity screen of ethanolic extracts of Heracleum mantegazzianum Sommier and Levier (giant hogweed), Centaurea jacea L. (brown knapweed), and Chenopodium album L. (Pigweed): Three invasive plants.

Background: Plants, including invasive ones, can play a significant role in the fight against antibiotic resistance and the search for new antimicrobials. Aims: The present study aimed at assessing the antimicrobial activity, antibioresistance reversal properties, and toxicity of four samples from invasive plants, namely, Heracleum mantegazzianum (leaves and flowers), Chenopodium album (leaves), and Centaurea jacea (flowers). Methods: The extraction of active compounds was done with ethanol (80%, v/v) and the extraction yields were calculated. Antimicrobial activity was studied using the agar-well diffusion method against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 6538, and Candida albicans ATCC 10231. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined using the mircodilution method. The antibioresistance reversal properties were assessed using the checkerboard method and the toxicity of the extracts was studied using the larval form of the Greater Wax Moth (Galleria mellonella). Results: The mass yields were 11.9, 15.0, 18.2, and 21.5, respectively, for C. jacea flower (CJF), H. mantegazzianum flower (HMF), H. mantegazzianum leaf (HML), and C. album leaf (CAL). The highest inhibition diameters (ID) were found with HMF, CAL, CJF, and HML against S. aureus with 26.6, 21.6, 21.0, and 20.0 mm, respectively. Only CJF and HMF were active against E. coli with respective ID of 15.3 and 19.0 mm. Except HMF (ID = 13.6 ± 2.0 mm), no other extract was active against C. albicans. Moreover, HMF exhibited the lowest MIC (0.5 mg/ml) and the lowest MBC (1 and 4 mg/ml) against both S. aureus and E. coli. Regarding the synergy test, an additional effect [0.5 ≤ fractional inhibitory concentration (FIC) ≤ 1] was found in almost all the combinations antibiotics + extracts excepted for HMF + (Kanamycin or Ampicillin) against S. aureus and CJF + Ampicillin against E. coli where we found synergy effect (FIC ≤0.5). The median lethal doses (LD50s) of HMF, HML, CAL, and CJF were 20.2, 0.58, 13.2, and 4.0 mg/ml, respectively. Conclusion: Only the ethanolic extract of HMFs showed noteworthy broad spectrum antimicrobial activity.

Chelation of Zinc with Biogenic Amino Acids: Description of Properties Using Balaban Index, Assessment of Biological Activity on Spirostomum Ambiguum Cellular Biosensor, Influence on Biofilms and Direct Antibacterial Action.

The complexation of biogenic molecules with metals is the widespread strategy in screening for new pharmaceuticals with improved therapeutic and physicochemical properties. This paper demonstrates the possibility of using simple QSAR modeling based on topological descriptors for chelates study. The presence of a relationship between the structure (J) and lipophilic properties (logP) of zinc complexes with amino acids, where two molecules coordinate the central atom through carboxyl oxygen and amino group nitrogen, and thus form a double ring structure, was predicted. Using a cellular biosensor model for Gly, Ala, Met, Val, Phe and their complexes Zn(AA)2, we experimentally confirmed the existence of a direct relationship between logP and biological activity (Ea). The results obtained using topological analysis, Spirotox method and microbiological testing allowed us to assume and prove that the chelate complex of zinc with methionine has the highest activity of inhibiting bacterial biofilms, while in aqueous solutions it does not reveal direct antibacterial effect.

Antibacterial Activity of Medicinal Plants against Uropathogenic Escherichia coli.

Urinary tract infections (UTIs) are one of the most common bacterial infections with uropathogenic Escherichia coli (UPEC) being the most prevalent causative agent in both complicated and uncomplicated UTIs. Antibiotic resistance among UPEC has been already demonstrated against a wide variety of antibiotics and the situation is continuing to deteriorate increasing the rate of recurrence and the difficulty of treatment and prophylaxis. Recently, a big attention has been paid to non-antibiotic approaches as an alternative to conventional antibiotics. Among many strategies, phytotherapy has gained a special attention worldwide. Herbal remedies have been used in traditional medicine since ancient times and they are well known for their effectiveness in treating many health conditions including UTIs. Researches are conducted continuously to validate the use of many medicinal plants against UPEC, investigate their mechanisms of action, and determine their active constituents. Our extensive review of the recent literature revealed that many phytochemicals are shown to target and inhibit a wide variety of bioprocesses in UPEC, such as adhesion, motility, biofilm formation, and quorum sensing. Such natural approaches are very promising in confronting the antibiotic resistance of UPEC and can be further used to develop plant-based strategies and pharmaceutical products to treat and prevent UTIs caused by UPEC.

Enhancement of the antifungal activity of some antimycotics by farnesol and reduction of Candida albicans pathogenicity in a quail model experiment.

Background and Aim: Clinical strains of microorganisms, including pathogenic yeast-like fungi (YLF), are resistant to currently used antifungal agents. Thus, it is relevant to study the combinations of existing antimicrobial drugs and a medicinal extract of plant origin (farnesol). In previous studies, farnesol showed a relatively strong anti-biofilm effect against Candida albicans. This study aimed to determine how much the resistance profile of non-biofilm microorganisms can change. Materials and Methods: Six clinical isolates of C. albicans and one reference strain were used to study the interaction of farnesol with the most used antimycotics. To determine the sensitivity of YLF to antimycotic drugs, such as nystatin (50 µg), amphotericin B (10 µg), ketoconazole (10 µg), clotrimazole (10 µg), voriconazole (10 µg), fluconazole (25 µg), miconazole (10 µg), and intraconazole (10 µg), the classic disk diffusion method was used. In the second stage, one of the six strains was used to simulate candidiasis of the gastrointestinal tract in an in vivo quail model. As an unusual experimental design, this study investigated the effects of pretreated C. albicans in quails, not the in vivo pathogenicity of C. albicans, after treatment with farnesol. Results: The resistance profiles of Candida strains did not improve with farnesol in all strains. All concentrations of farnesol (100, 50, and 25 µM) demonstrated a fungistatic effect (i.e., an increase in drug sensitivity) in 23 of 56 (7×8) cases (41%). The remaining 54% demonstrated no changes in the resistance to antifungal drugs or deterioration of the indicators in rare cases (5%). At 100 µM farnesol, sensitivity improved in 33 of 56 cases (59%). Candidiasis or the severity of clinical disease of the quail digestive tract developed to a lesser extent if fungi were treated with farnesol. Conclusion: Farnesol does not always show a positive result on single cells without biofilm in the laboratory. However, in a biofilm or an in vivo model with biofilms, farnesol can be considered a new antimycotic drug or an additive to existing antimycotics.

The public health issue of antibiotic residues in food and feed: Causes, consequences, and potential solutions.

Antibiotics are among the essential veterinary medicine compounds associated with animal feed and food animal production. The use of antibiotics for the treatment of bacterial infections is almost unavoidable, with less need to demonstrate their importance. Although banned as a growth factor for a few years, their use in animals can add residues in foodstuffs, presenting several environmental, technological, animal health, and consumer health risks. With regard to human health risks, antibiotic residues induce and accelerate antibiotic resistance development, promote the transfer of antibiotic-resistant bacteria to humans, cause allergies (penicillin), and induce other severe pathologies, such as cancers (sulfamethazine, oxytetracycline, and furazolidone), anaphylactic shock, nephropathy (gentamicin), bone marrow toxicity, mutagenic effects, and reproductive disorders (chloramphenicol). Antibiotic resistance, which has excessively increased over the years, is one of the adverse consequences of this phenomenon, constituting a severe public health issue, thus requiring the regulation of antibiotics in all areas, including animal breeding. This review discusses the common use of antibiotics in agriculture and antibiotic residues in food/feed. In-depth, we discussed the detection techniques of antibiotic residues, potential consequences on the environment and animal health, the technological transformation processes and impacts on consumer health, and recommendations to mitigate this situation.

Diplocloster agilis gen. nov., sp. nov. and Diplocloster modestus sp. nov., two novel anaerobic fermentative members of Lachnospiraceae isolated from human faeces.

Three novel strains of Gram-stain-negative, obligately anaerobic, spore-forming straight or slightly curved rods with pointed ends occurring singly or in pairs were isolated from the faeces of healthy human children. The strains were characterized by mesophilic fermentative metabolism and production of acetate, ethanol and H2 as the end metabolic products. Strains ASD3451 and ASD5720T were motile, fermented lactose and raffinose, and weakly fermented maltose. Strain ASD4241T was non-motile and did not ferment the carbohydrates listed above but fermented starch. Strains ASD3451 and ASD5720T shared average nucleotide identity higher than 98.5 % with each other, while ASD4241T had only 88.5-89 % identity to them. Based on phylogenetic and chemotaxonomic analyses, we propose Diplocloster agilis gen. nov., sp. nov. (ASD5720T=JCM 34353T=VKM B-3497T) and Diplocloster modestus sp. nov. (ASD4241T=JCM 34351T=VKM B-3498T) within the family Lachnospiraceae.

Influence of geographic conditions on body length of male newborns in Kyrgyzstan.

Newborn length has been reported by many researchers to be reduced at high altitudes. However, many of these studies lacked adequate control of the ethnic group which may be confounding the altitude differences. In addition, few studies have examined the sources of variation in birth weight at high altitudes that may be related to ethnic group adaptation to the stresses of this hypoxic environment. In our study, we tested the hypotheses that the effect of altitude differences in newborn length depends on ethnic variation. Samples of 3359 healthy male newborns from different areas in Kyrgyzstan between the years 2003 and 2011 were analyzed for altitude and ethnic variation on male newborn length. Our results indicate significant decrease in male newborn length as a latitude increase. It is concluded that ethnic group difference in pregnancy outcome reflects a better state of adaptation to high altitude in this healthy indigenous population and that long-term genetic selection may be the most plausible explanation for these ethnic differences.

Antibacterial Poly(ε-CL)/Hydroxyapatite Electrospun Fibers Reinforced by Poly(ε-CL)-b-poly(ethylene phosphoric acid).

In bone surgery and orthopedics, bioresorbable materials can be helpful in bone repair and countering post-op infections. Explicit antibacterial activity, osteoinductive and osteoconductive effects are essential to achieving this objective. Nonwoven electrospun (ES) fibers are receiving the close attention of physicians as promising materials for wound dressing and tissue engineering; potentially, in high contrast with dense materials, ES mats hamper regeneration of the bone extracellular matrix to a lesser extent. The use of the compositions of inherently biodegradable polyesters (poly(ε-caprolactone) PCL, poly(lactoglycolide), etc.), calcium phosphates and antibiotics is highly prospective, but the task of forming ES fibers from such compositions is complicated by the incompatibility of the main organic and inorganic ingredients, polyesters and calcium phosphates. In the present research we report the synthesis of hydroxyapatite (HAp) nanoparticles with uniform morphology, and demonstrate high efficiency of the block copolymer of PCL and poly(ethylene phosphoric acid) (PEPA) as an efficient compatibilizer for PCL/HAp mixtures that are able to form ES fibers with improved mechanical characteristics. The materials obtained in the presence of vancomycin exhibited incremental drug release against Staphylococcus aureus (St. aureus).

Morphological characteristics of Candida albicans, Candida krusei, Candida guilliermondii, and Candida glabrata biofilms, and response to farnesol.

BACKGROUND AND AIM: Different Candida species isolated in humans and animals have different types of parasite activity. The most pathogenic species is Candida albicans followed by Candida tropicalis. However, the effects of the morphology of Candida krusei, Candida guilliermondii, and Candida glabrata biofilms on the pathogenicity of these species have not been fully characterized. To the best of our knowledge, there is no literature on the effect of farnesol on rare Candida species. This study aimed to check the effect of different farnesol concentrations on the species C. krusei, C. guilliermondii, and C. glabrata compared with the strain C. albicans ATCC 10231, which has been widely studied, and is a strong producer of biofilms. MATERIALS AND METHODS: We studied the morphological and densitometric parameters of biofilms produced by Candida species under the influence of the drug farnesol (Sigma-Aldrich, St. Louis, MO). We used a heart brain broth with the addition of 2% bovine blood serum in 96-well plates. To each well, we added 100 mL of C. albicans, C. krusei, C. guilliermondii, or C. glabrata culture, and 0.2-400 mM farnesol. The microliter plates were cultured with the lid closed at 37°C for 48 h. Then, the liquid was removed, and the wells were washed 3 times with 200 mL phosphate buffer solution (pH 7.3). Biofilm fixation was performed using 150 mL of 96% ethanol for 15 min. Then, the microliter plates were dried for 20 min at 37°C, a 0.5% solution of crystalline violet was added, and the plates were placed in an incubator at 37°C. After 5 min, the contents of the wells were removed, washed 3 times with 200 mL of phosphate buffer solution (pH 7.2), and dried. The dye was extracted by washing with 200 mL of 96% ethanol for 30 min. The results were obtained using a photometric analyzer of enzyme immunoassay reactions at an optical density (OD) wavelength of 450 nm. RESULTS: All of Candida spp. strains tested were susceptible to farnesol at concentrations ranging from 0.8 to 400 mM for C. albicans, C. krusei, and C. guilliermondii, and 12.5 to 400 mM for C. glabrata. CONCLUSION: This study provides new insights into the use of farnesol against biofilms produced by Candida species, but further studies in vivo are necessary to evaluate the effectiveness of the reduction of OD. To the best of our knowledge, the antimicrobial activity of farnesol against C. krusei, C. guilliermondii, and C. glabrata has not been reported previously, although studies have confirmed the inhibitory effect of farnesol on the growth of different microorganisms.

Galleria mellonella (greater wax moth) as an eco-friendly in vivo approach for the assessment of the acute toxicity of medicinal plants: Application to some plants from Cameroon.

BACKGROUND: The evaluation of medicinal plants' toxicity is a prerequisite prior to their usage. The vertebrate models used for this purpose are often the object of ethical consideration. Though invertebrate models including Galleria mellonella (GM) have demonstrated the ability to be used to assess the toxicity of various products. To the authors' knowledge, GM has never been exploited to determine the toxicity of medicinal plants. AIM: The aim of this study was to demonstrate the potential of GM larvae as a simple, inexpensive, and rapid model for the evaluation of the toxicity of herbal medicines. METHOD: In this study, the toxicity of aqueous and ethanolic (80%, v/v) extracts of seven well known plants from Cameroon namely leaves of Cymbopogon citratus (DC.) Stapf, Moringa oleifera Lam and Vernonia amygdalina Delile; barks of Cinchona officinalis and Enantia chlorantha Oliv; barks and seeds of Garcinia lucida Vesque and leaves and seeds of Azadirachta indica (Neem) was evaluated using the larval form of GM. The median lethal doses (LD50), 90% (LD90), and 100% (LD100) were determined using the spline cubic survival curves and equations from the data obtained on the survival rate of GM 24 hours after the injection with the extracts. RESULTS: We found that distilled water extracted a more important mass of phytochemical compounds (7.4%-21.2%) compared to ethanolic solution (5.8%-12.4%). LD varied depending on the plant materials and ethanolic extracts (hydroalcoholic extract, (HAE)) were more toxic to GM than aqueous ones. The LD50 (mg/ml) of the tested extracts varied from 4.87 [3.90 g/kg body weight (bw)] to >200 (> 166.67 g/kg bw), the LD90 (mg/ml) from 25.00 (18.52 g/kg bw) to >200 (> 181.82 g/kg bw) and LD100 (mg/ml) from 45.00 (40.91 g/kg bw) to > 200 (>181.82 g/kg bw). The HAE of A. indica seed and C. officinalis bark exhibited the highest toxicity with LD50 (g/kg bw) of 3.90 and 4.81, respectively. CONCLUSION: The results obtained in this study suggest that GM can be used as a sensitive, reliable, and robust eco-friendly model to gauge the toxicity of medicinal plants. Thus, avoid the sacrifice of vertebrate models often used for this purpose to limit ethical concerns.

Prevotella rara sp. nov., isolated from human faeces.

A strain of obligately anaerobic, Gram-stain-negative rods was isolated from human faeces and characterized both phenotypically and genotypically. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences revealed the strain to represent a member of the genus Prevotella, distant from the species with validly published names, with the closest relationship to Prevotella oryzae. The strain was moderately saccharolytic and proteolytic. The predominant menaquinones were MK-13 and MK-12. The major cellular long-chain fatty acids were anteiso-C15 : 0 and iso-C15 : 0. The genomic DNA G+C content was 45.7 mol%. On the basis of chemotaxonomic and genotypic properties, it was concluded that the strain represent a novel species within the genus Prevotella, for which the name Prevotellarara sp. nov. is proposed. The type strain of Prevotellarara is 109T (=VKM B-2992T=DSM 105141T).