Anaerobic Clostridium Research Articles

The Influence of Commercial Feed Supplemented with Carnobacterium maltaromaticum Environmental Probiotic Bacteria on the Rearing Parameters and Microbial Safety of Juvenile Rainbow Trout.

The aim of this study was to determine the effect of commercial feed (CF) supplemented with 0.1% of the Carnobacterium maltaromaticum environmental probiotic strain on the rearing parameters, apparent nutrient digestibility, and microbial safety of juvenile rainbow trout (Oncorhynchus mykiss). The fish were fed CF (control group, CG) and experimental feed (EF) supplemented with 0.1% of C. maltaromaticum (experimental group, EG) for 56 days. The final body weight and total body length of the fish were measured. The growth rate, condition factor, feed conversion ratio, viscerosomatic and hepatosomatic indices, and apparent digestibility coefficients of protein (PAD), lipids (LAD), ash (AAD), and nitrogen-free extract (NFEAD) were calculated. The total viable counts of C. maltaromaticum bacteria, mesophilic bacteria, hemolytic mesophilic bacteria, Pseudomonas fluorescens, Aeromonas hydrophila, Staphylococcus sp., and sulfite-reducing anaerobic spore-forming Clostridium sp. were determined in digestive tract contents and the skin of fish. Feed supplementation with C. maltaromaticum significantly affected most rearing parameters, as well as the PAD, LAD, AAD and NFE values, and bacterial counts. The principal component analysis (PCA) revealed significant positive correlations (p < 0.05) between fish growth rates, PAD and LAD values vs. C. maltaromaticum counts in the EF and in the digestive tract contents of the fish.

Sugarcane Biomass as a Source of Biofuel for Internal Combustion Engines (Ethanol and Acetone-Butanol-Ethanol): A Review of Economic Challenges

The objective of this review is to provide a deep overview of liquid biofuels produced from sugarcane bagasse and to address the economic challenges of an ethanol and acetone-butanol-ethanol blend in commercial processes. The chemistry of sugarcane bagasse is presented. Pretreatment technologies such as physical, chemical pretreatment, biological, and combination pretreatments used in the fermentation process are also provided and summarised. Different types of anaerobic bacteria Clostridia (yeast) are discussed to identify the ingredient best suited for sugarcane bagasse, which can assist the industry in commercializing ethanol and acetone-butanol-ethanol biofuel from biomass sugarcane. The use of an acetone-butanol-ethanol mixture and ethanol blend in internal combustion engines is also discussed. The literature then supports the proposal of the best operating conditions for fermentation to enhance ethanol and acetone-butanol-ethanol plant efficiency in the sugar waste industry and its application in internal combustion engines.

Epidemiology and antibiotic susceptibility profiles of obligate anaerobes in a hospital of central Italy during a one-year (2019) survey

ObjectivesIn this study, we report on the epidemiology and susceptibility profiles of anaerobic pathogens consecutively isolated from various clinical samples at an Italian hospital during a one-year survey. MethodsThe collection included all non-duplicated consecutively collected anaerobic clinical isolates during 2019 in San Luca Hospital (Lucca, Italy). Antimicrobial susceptibility testing was performed using MICRONAUT-S Anaerobes MIC lyophilized plates (MERLIN Diagnostika, Germany) and interpreted using EUCAST criteria (11.0). ResultsA total of 169 Gram-negative and 213 Gram-positive were collected. The most frequent anaerobes were Bacteroides spp. (120, 31.4%) followed by Finegoldia magna (62, 16.2%). External ulcers were the most common source of isolates (39%), followed by blood (25.7%). In 230 patients (65%) polymicrobial aerobic/anaerobic isolates were cultured from the same external ulcer specimen. High resistance rates to clindamycin were overall detected, with the highest values among the genera Parabacteroides, Bacteroides, Prevotella, Gram-positive anaerobic cocci and Clostridium. High resistance rates were also observed to metronidazole among both Gram-positive and Gram-negative species, ranging between 10.8-50% and 13.8–46.2%, respectively. ConclusionsOur findings revealed that anaerobes susceptibility patterns have become less predictable due to an increase of resistance and suggest that periodic resistance surveillance should also be carried out for anaerobes in order to guide empirical therapy.

Whole cell of pure Clostridium butyricum CBT-1 from anaerobic bioreactor effectively hydrolyzes agro-food waste into biohydrogen.

Recycling organic waste and converting them into renewable energy are a promising route for environment protection and effective biochemical reactions suitable for industrial hydrogen synthesis. This study targeted to isolate a pure anaerobic culture with potential to hydrolyze different biomass and production of biohydrogen. For this, a sample of full-scale anaerobic digester, fed with a multicomponent solid, was inoculated on Reinforced Clostridial Medium (RCM) in strict anaerobic conditions. An anaerobic Clostridium butyricum CBT-1 strain was isolated, identified from morphological and 16S rRNA sequence. The CBT-1 culture expressed amylase, cellulase and peroxidases activities. The strain exhibited visual decolorization of both Azure B and crystal violet dyes. In batch fermentation experiment, the CBT-1 produced highest of 3.06, 2.67 and 2.46 mol/mol H2 yield from glucose, starch and cellulose respectively, whereas, the CBT-1 showed low 0.43 mol H2/mol of substrate from untreated rice straw due to lignin in compact structure and comparatively high H2 yield of 1.91 and 2.01 mol H2/mol of substrate rice straw hydrolysate and kitchen food waste (KFWS) respectively. The cumulative volumetric yield of H2 was 358.15, 300.8 and 294.5NmL/gSub from glucose, starch and cellulose respectively. Similarly, the cumulative H2 volume was 76.7, 184.4, 237.2 NmL/gVS from untreated rice straw, rice straw hydrolysate and kitchen food waste. This study emphasizes the prospects to find similar robust anaerobic culture for hydrolyzing complex biomass. Such strains could be used as standard co-inoculum for biohydrogen obtaining and as the biocatalyst for commercial scale applications.

Declining carbohydrate solubilization with increasing solids loading during fermentation of cellulosic feedstocks by Clostridium thermocellum: documentation\xa0and diagnostic tests

BackgroundFor economically viable 2nd generation biofuels, processing of high solid lignocellulosic substrate concentrations is a necessity. The cellulolytic thermophilic anaerobe Clostridium thermocellum is one of the most effective biocatalysts for solubilization of carbohydrate harbored in lignocellulose. This study aims to document the solubilization performance of Clostridium thermocellum at increasing solids concentrations for two lignocellulosic feedstocks, corn stover and switchgrass, and explore potential effectors of solubilization performance.ResultsMonocultures of Clostridium thermocellum demonstrated high levels of carbohydrate solubilization for both unpretreated corn stover and switchgrass. However, fractional carbohydrate solubilization decreases with increasing solid loadings. Fermentation of model insoluble substrate (cellulose) in the presence of high solids lignocellulosic spent broth is temporarily affected but not model soluble substrate (cellobiose) fermentations. Mid-fermentation addition of cells (C. thermocellum) or model substrates did not significantly enhance overall corn stover solubilization loaded at 80 g/L, however cultures utilized the model substrates in the presence of high concentrations of corn stover. An increase in corn stover solubilization was observed when water was added, effectively diluting the solids concentration mid-fermentation. Introduction of a hemicellulose-utilizing coculture partner, Thermoanaerobacterium thermosaccharolyticum, increased the fractional carbohydrate solubilization at both high and low solid loadings. Residual solubilized carbohydrates diminished significantly in the presence of T. thermosaccharolyticum compared to monocultures of C. thermocellum, yet a small fraction of solubilized oligosaccharides of both C5 and C6 sugars remained unutilized.ConclusionDiminishing fractional carbohydrate solubilization with increasing substrate loading was observed for C. thermocellum-mediated solubilization and fermentation of unpretreated lignocellulose feedstocks. Results of experiments involving spent broth addition do not support a major role for inhibitors present in the liquid phase. Mid-fermentation addition experiments confirm that C. thermocellum and its enzymes remain capable of converting model substrates during the middle of high solids lignocellulose fermentation. An increase in fractional carbohydrate solubilization was made possible by (1) mid-fermentation solid loading dilutions and (2) coculturing C. thermocellum with T. thermosaccharolyticum, which ferments solubilized hemicellulose. Incomplete utilization of solubilized carbohydrates suggests that a small fraction of the carbohydrates is unaffected by the extracellular carbohydrate-active enzymes present in the culture.

Detoxification of Copper and Chromium via Dark Hydrogen Fermentation of Potato Waste by Clostridium butyricum Strain 92

The accumulation of various types of waste containing both organic and inorganic metal-containing compounds is extremely hazardous for living organisms. The possibility of polymer degradation, biohydrogen synthesis, and metal detoxification via the dark fermentation of model potato waste was investigated. For this purpose, the strict anaerobic strain was isolated and identified as Clostridium butyricum. The high efficiency of dark hydrogen fermentation of potatoes with yield of hydrogen in 85.8 ± 15.3 L kg−1 VSpotato was observed. The copperand chromium salts solutions were added to the culture fluid to obtain the concentrations of 50, 100, and 200 mg L−1 Cu(II) and Cr(VI) in the active phase of growth (19 h of cultivation). Metals at a concentration of 200 mg L−1 inhibited the fermentation process the most. The hydrogen yield decreased in 7.2 and 3.6 times to 11.9 ± 2.1 and 23.8 ± 5.6 L kg−1 VSpotato in the presence of 200 mg L−1 Cu(II) and Cr(VI), respectively. The efficiencies of the chromium bioremoval in all variants of the experiment were 100%, and those of copper bioremoval were about 90%. A pure culture of strict anaerobes Clostridium butyricum strain 92 was used for the first time for the detoxification of metals. The presented results confirmed the possibility of this promising strain application for industrial H2 production and the bioremediation of contaminated sites.

Validation of a real-time PCR method on pta gene for Clostridium tyrobutyricum quantification in milk

In the dairy industry, the late blowing defect in medium and long ripened cheeses causes important economic losses. This cheese defect, caused mainly by the anaerobic spore former Clostridium tyrobutyricum , is characterized by gas production resulting in holes formation in the paste, and in unpleasant aromas related to the butyrate production. Since longtime, the reference method used to detect the presence of total spore number in milk is the Most Probable Number (MPN), a semi-quantitative method which measures the bacterial growth and the gas production after heat treatment of the samples. This method often gives uncertain results, it requires long incubation periods and fails to differentiate between different species of spore-forming bacteria. A TaqMan real-time quantitative PCR targeting the phosphotransacetylase gene ( pta ) for C. tyrobutyricum was previously developed as an alternative technique to the traditional method, faster and more specific, and therefore of great interest to preventively determine the contamination of milk by C. tyrobutyricum . The aim of this work was the validation of this quantitative real-time PCR protocol for the C. tyrobutyricum detection in milk. Following the method validation, 120 samples of UHT and raw milk artificially contaminated with C. tyrobutyricum spores were analyzed in increasing concentrations, relating the results of the molecular method with those obtained by the MPN. Finally, 144 raw milk samples with a possible natural contamination were analyzed and demonstrated a positivity rate of 15.28% (CI95% 10.31–22.05%). • Validation of a real-time PCR for the C. tyrobutyricum detection in milk. • Method application on both spiked and naturally contaminated samples. • Rapid method to monitor the milk quality to avoid the late blowing defect.

A Heterodimeric Reduced-Ferredoxin-Dependent Methylenetetrahydrofolate Reductase from Syngas-Fermenting Clostridium ljungdahlii.

ABSTRACTThe strict anaerobe Clostridium ljungdahlii can ferment CO or H2/CO2 via the Wood-Ljungdahl pathway to acetate, ethanol, and 2,3‐butanediol. This ability has attracted considerable interest, since it can be used for syngas fermentation to produce biofuels and biochemicals. However, the key enzyme methylenetetrahydrofolate reductase (MTHFR) in the Wood-Ljungdahl pathway of the strain has not been characterized, and its physiological electron donor is unclear. In this study, we purified the enzyme 46-fold with a benzyl viologen reduction activity of 41.2 U/mg from C. ljungdahlii cells grown on CO. It is composed of two subunits, MetF (31.5 kDa) and MetV (23.5 kDa), and has an apparent molecular mass of 62.2 kDa. The brownish yellow protein contains 0.73 flavin mononucleotide (FMN) and 7.4 Fe, in agreement with the prediction that MetF binds one flavin and MetV binds two [4Fe4S] clusters. It cannot use NAD(P)H as its electron donor or catalyze an electron-bifurcating reaction in combination with ferredoxin as an electron acceptor. The reduced recombinant ferredoxin, flavodoxin, and thioredoxin of C. ljungdahlii can serve as electron donors with specific activities of 91.2, 22.1, and 7.4 U/mg, respectively. The apparent Km values for reduced ferredoxin and flavodoxin were around 1.46 μM and 0.73 μM, respectively. Subunit composition and phylogenetic analysis showed that the enzyme from C. ljungdahlii belongs to MetFV-type MTHFR, which is a heterodimer, and uses reduced ferredoxin as its electron donor. Based on these results, we discuss the energy metabolism of C. ljungdahlii when it grows on CO or H2 plus CO2.IMPORTANCE Syngas, a mixture of CO, CO2, and H2, is the main component of steel mill waste gas and also can be generated by the gasification of biomass and urban domestic waste. Its fermentation to biofuels and biocommodities has attracted attention due to the economic and environmental benefits of this process. Clostridium ljungdahlii is one of the superior acetogens used in the technology. However, the biochemical mechanism of its gas fermentation via the Wood-Ljungdahl pathway is not completely clear. In this study, the key enzyme, methylenetetrahydrofolate reductase (MTHFR), was characterized and found to be a non-electron-bifurcating heterodimer with reduced ferredoxin as its electron donor, representing another example of MetFV-type MTHFR. The findings will form the basis for a deeper understanding of the energy metabolism of syngas fermentation by C. ljungdahlii, which is valuable for developing metabolic engineering strains and efficient syngas fermentation technologies.

Utility and Importance of Blending of BIOVITA 3 Bacterial Species in Intestinal Health

BIOVITA 3 bacterial species (Clostridium butyricum, Lactobacillus sporogenes, and Bacillus subtilis) are spore forming probiotic bacteria that are blended as granules. Unlike lactic acid bacteria, which account for most of the available probiotics, the BIOVITA 3 bacterial species are easy to store and stably transit to the intestine, where they promote intestinal health owing to the unique features of the individual strains. The BIOVITA 3 bacterial species differ in their proliferation in different regions of the intestinal tract because of their differing oxygen demands. The aerobic Bacillus subtilis mainly proliferates in the upper small intestine, which has a high oxygen concentration. The facultative anaerobe Lactobacillus sporogenes proliferates well in the small intestine. The anaerobic Clostridium butyricum grows best in the large intestine, which has a relatively low oxygen concentration. In addition, each bacterial species displays positive effects on promoting the growth of bacteria resident in the lower intestine. The differential proliferation of the BIOVITA 3 bacterial species influences intestinal regulation throughout the intestine from the small to the large intestine. The species also improve intestinal regulation through mutual interactions that increase the growth of other beneficial bacteria.

Microbial community structure, co-occurrence network and fermentation characteristics of woody plant silage.

Feed shortage is a factor restricting animal production in the tropics, therefore how to use natural woody plant resources as animal feed is an important strategy. Under the dual stress of an anaerobic and acidic environment, the microbial response during the fermentation of paper mulberry (PM) silage was found to be sensitive. The Gram-negative bacteria and mould died, and the dominant microbial community rapidly shifted to Gram-positive bacteria, resulting in a large reduction in microbial diversity and abundance. Exogenous bran additives interfered with the stress effects of the woody silage environment. Wheat bran (WB) accelerated the response of microorganisms to the anaerobic stress, and lactic acid bacteria became the dominant microbial community, thereby enhancing the lactic acid fermentation of silage, affecting the metabolic pathways of microorganisms, and improving the flavour and quality of the silage. Addition of rice bran made Enterobacter and Clostridium species quickly respond to the stress of the silage environment and become the predominant bacterial groups. In particular, anaerobic and spore-forming Clostridium species showed a strong tolerance to the silage environment, leading to butyric acid fermentation and protein degradation of the silage, and reducing its fermentation quality. The PacBio single-molecule real-time (SMRT) sequencing technology accurately revealed the microbial co-occurrence network and fermentation mechanism of silage. Our results indicate that PM can be used in combination with WB to prepare high-quality silage for animal production. © 2021 Society of Chemical Industry.

Unique Gut Microbiome in HIV Patients on Antiretroviral Therapy (ART) Suggests Association with Chronic Inflammation.

ABSTRACTChronic inflammation is a hallmark of human immunodeficiency virus (HIV) infection and a risk factor for the development and progression of age-related comorbidities. Although HIV-associated gut dysbiosis has been suggested to be involved in sustained chronic inflammation, there remains a limited understanding of the association between gut dysbiosis and chronic inflammation during HIV infection. Here, we investigated compositional changes in the gut microbiome and its role in chronic inflammation in patients infected with HIV. We observed that the gut microbiomes of patients with low CD4 counts had reduced alpha diversity compared to those in uninfected controls. Following CD4 recovery, alpha diversity was restored, but intergroup dissimilarity of bacterial composition remained unchanged between patients and uninfected controls. Patients with HIV had higher abundance of the classes Negativicutes, Bacilli, and Coriobacteriia, as well as depletion of the class Clostridia. These relative abundances positively correlated with inflammatory cytokines and negatively correlated with anti-inflammatory cytokines. We found that gut dysbiosis accompanying HIV infection was characterized by a depletion of obligate anaerobic Clostridia and enrichment of facultative anaerobic bacteria, reflecting increased intestinal oxygen levels and intestinal permeability. Furthermore, it is likely that HIV-associated dysbiosis shifts the immunological balance toward inflammatory Th1 responses and encourages proinflammatory cytokine production. Our results suggest that gut dysbiosis contributes to sustaining chronic inflammation in patients with HIV infection despite effective antiretroviral therapy and that correcting gut dysbiosis will be effective in improving long-term outcomes in patients.IMPORTANCE Chronic inflammation is a hallmark of HIV infection and is associated with the development and progression of age-related comorbidities. Although the gastrointestinal tract is a major site of HIV replication and CD4+ T-cell depletion, the role of HIV-associated imbalance of gut microbiome in chronic inflammation is unclear. Here, we aimed to understand the causal relationship between abnormalities in the gut microbiome and chronic inflammation in patients with HIV. Our results suggest HIV-associated gut dysbiosis presents a more aerobic environment than that of healthy individuals, despite prolonged viral suppression. This dysbiosis likely results from a sustained increase in intestinal permeability, which supports sustained bacterial translocation in HIV patients, despite effective therapy. Additionally, we observed that several bacterial taxa enriched in HIV patients were associated with increased expression of inflammatory cytokines. Collectively, these results suggest that gut dysbiosis plays an important role in chronic inflammation in HIV patients.

Stability of Ready-to-Use and Laboratory-Prepared Culture Media

The culture media quality, which depends to a large extent on growth promotion properties, determines the reliability and accuracy of test results obtained by microbiological methods. The procedure for culture media preparation is quite labourconsuming and includes several stages: successive dissolution of components exactly as specified in the recipe (qualitative and quantitative composition), sterilisation, adjusting the pH of the medium, and testing of growth promotion properties—therefore it is important to demonstrate the stability of each particular culture medium.The aim of the study was to evaluate growth promotion properties of the culture media prepared in the laboratory from a dry mixture, and to assess their stability during long-term storage.Materials and methods: stability testing was performed for fluid thioglycollate medium (FTM) and soybean-casein digest broth (SCD) prepared in the laboratory. FTM growth promotion properties were tested using the following test microorganisms: Bacillus subtilis ATCC 6633, Clostridium sporogenes ATCC 19404, Pseudomonas aeruginosa ATCC 9027, Staphylococcus aureus ATCC 6538. SCD growth promotion properties were tested using: Aspergillus brasiliensis ATCC 16404, Candida albicans ATCC 10231, Bacillus subtilis ATCC 6633. The stability study was carried out for 6 months, assessing changes in appearance and growth promotion properties. The test media were stored at room temperature and in a refrigerator at 2–8 °C.Results: no growth of the anaerobic microorganism Clostridium sporogenes was observed in FTM after 3 months, regardless of storage conditions. Later on, there was no growth of the gram-positive microorganisms Bacillus subtilis and Staphylococcus aureus, which are more sensitive to the storage conditions than Pseudomonas aeruginosa. The growth promotion properties of the SCD prepared in the laboratory did not change during 6 months of storage.Conclusions: FTM prepared from a dry mixture remains stable and retains its growth promotion properties for no more than two months when stored in a refrigerator at 2–8 °C. SCD can remain stable for 6 months, both at room temperature and when stored in the refrigerator.

Fermented Rapeseed Meal as a Component of the Mink Diet (Neovison vison) Modulating the Gastrointestinal Tract Microbiota.

Fermented rapeseed meal (FRSM) was used in the diet of American mink (Neovison vison). An advantage of this product is its prebiotic and functional properties, which can modify the bacterial microbiota of the GIT. A control group and three experimental groups were formed, with 60 animals in each group. The control group received a basal diet and the experimental groups received a diet with a 2%, 4% or 6% of FRSM as a replacement of extruded wheat. Bacillus subtilis strain 87Y was used to ferment the rapeseed meal (RSM). The study was conducted on mink from the age of 16-17 weeks until slaughter. Changes in the microbiota were analysed in samples of the animals' faeces and intestinal contents. The analyses included determination of the total number of bacteria and fungi, the number of coliforms and Escherichia coli, the total number of anaerobic Clostridium perfringens, and the presence of Salmonella spp. In animals receiving 4% and 6% FRSM (groups II and III), the content of microscopic fungi and the number of C. perfringens bacteria was significantly (p ≤ 0.05) lower than in the animals from the control group (group 0). A decrease in E. coli was observed in all experimental groups (I, II and III), although these differences were not statistically significant. The inclusion of FRSM in the feed ration did not affect the number of lactic acid intestinal bacteria. Analysis of the results obtained from the stool samples showed that the inclusion of FRSM in the ration did not significantly affect the number of microorganisms in each group. However, as in the case of the intestinal contents, in these samples there was a decrease in the total number of C. perfringens in the experimental groups (I, II and III), with a simultaneous increase in the number of mesophilic bacteria in relation to the control. There was no detection of Salmonella bacteria in any of the analysed material.

Role of microbubbles coupling fibrous-bed bioreactor in butyric acid production by Clostridium tyrobutyricum using Brewer’s spent grain as feedstock

Microbubbles coupling fermentation is an efficient technology for improving oxygen transfer to aerobic microorganisms in a bioreactor containing an air sparger. However, the effect of this technology on anaerobic Clostridium tyrobutyricum, whose morphology develops viscous broth rheology and lumps impeding the nutrient mass transfer, has not been reported yet. Therefore, we evaluated the role of microbubbles coupling fibrous-bed bioreactor (MBFBB) on butyrate production by immobilized Clostridium tyrobutyricum cells obtained from renewable feedstock brewer’s spent grain (BSG). Compared with the conventional fibrous-bed bioreactor (FBB) fermentation, two-fold shorter fermentation time and two-fold higher butyrate productivity were achieved by MBFBB-immobilized C. tyrobutyricum cells. Furthermore, long-term stability and reliability for butyrate production were obtained in ten cycle process using BSG hydrolysate. Finally, fed-batch fermentation using BSG hydrolysate produced a high butyrate titer of 43.68 g/L, with a significantly higher selectivity of 11.67, reducing the production cost of downstream processing. The results also indicated that butyrate productivity of 5.40 g/(L h were successfully obtained in BSG medium, thereby representing the highest productivity reported to date in C. tyrobutyricum from low-cost feedstocks. To our knowledge, this is also the first report related to microbial production of butyrate from BSG. Based on techno-economic analysis, it was demonstrated that the MBFBB-based fermentation process with BSG, was robust, economic and should underpin the future development of commercial biobutyrate production.

Рентгеновская компьютерная томография структуры корней и динамика почвенной биоты на ранних стадиях роста ячменя (Hordeum vulgare L.)

The architecture of the seed bed, a certain alternation of compacted and loose sections of the arable horizon, largely determines the development of the root system of plants. The morphology and growth of the root system of the germinating seed in the created seed bed is also determined by the composition of the surrounding soil biota. Dynamic studies of the development of the root system and composition of the surrounding soil biota is an essential methodological and practical problem in soil cultivation, agrophysics, and soil biology. This task is especially important in the first few days when the root system is laid and the plant rhizosphere is formed. Modern tomography makes it possible to carry out such studies that do not violate the soil-root biological system, in particular, in model mesoscale experimental physical models. The aim of this research was to use x-ray computed tomography to study the structure of the roots of barley seedlings in the early stages of development, while simultaneously studying changes in the number and dominant groups of microorganisms in the basal biota. Barley seeds (variety Mikhailovsky) in a model physical experiment with a twolayer soil bed density (soil density range from 0.7 to 1.2 g / cm3) Albic Glossic Retisols (Lomic, Cutanic), WRB, 2014 were laid for germination at the layer boundary in a special cylindrical box with a volume of about 3 cm3 at optimal humidity. The position of the seed in the soil of the seedbed model is shown in the tomographic image (See Fig. 1). During the period from planting to 7 days, the dynamics of the root system was studied using a Bruker X-ray microtomography “SkyScan 1172G” (Bruker, Belgium) while studying the composition of soil biota, which was reconstructed by microbial markers (fatty acids and their derivatives). Markers were determined by molecular gas chromatography - mass spectrometry. Computer tomography allowed to record the volume distribution of roots at different periods of germination in the aggregated and compacted layers of agro-sod-podzolic soil. In this case, the roots successfully mastered the entire soil space, regardless of the plowing architecture of soil density created at the initial stage of germination. The total number of bacteria also increased by the 5th day with the constant dominance of 3 phyla: Actinobacteria, Proteobacteria and Firmicutes in the biota; the other two, Bacteroidetes and Cyanobacteria, were represented in relatively small numbers. In the phylum Actinobacteria, aerobic hydrolytics of complex carbohydrates Rhodococcus equi were presented in the largest amount on the 5th day, in the Firmicutes phylum it is anaerobic hydrolytic Ruminococcus sp. and the anaerobic nitrogen fixator Clostridium pasteurianum, in the phylum Proteobacteria-the aerobic nitrifier Nitrobacter sp. with a subsequent decrease in the number on the 7th day. The increase in these species indicates the initial destruction of the cellulose shell of the grain and the processes of fixation and conversion of nitrogen in the microbiota of the germinating seed, necessary for the formation of the C/N ratio. During the germination of the seed, pores are formed that are filled with water, gas, or organic matter. The structure of the microbial community changes in response to the ongoing processes, while the accumulation of metabolic products of aerobic and anaerobic species of microorganisms occurs. The quantitative study of the complex of microorganisms by the molecular method allows us to display the reaction of the microbiome to structural changes in the soil, since certain conditions stimulate an increase in the share of species with appropriate ecological functions in the community. The combination with the computer visualization obtained as a result of the application of the X-ray tomography method makes it possible to more clearly characterize the processes occurring in the rhizosphere.

Synthetic Biology Medicine and Bacteria-Based Cancer Therapeutics.

Spontaneous tumor regression following bacterial infection has been observed for hundreds of years. These observations along with anecdotal medical findings in 1890s led to the development of Coley's "toxins," consisting of killed Streptococcus pyogenes and Serratia marcescens bacteria, as the first cancer immunotherapy. The use of this approach, however, was not widely accepted at the time especially after the introduction of radiation therapy as a treatment for cancer in the early 1900s. Over the last 30-40years there has been renewed interest in the use of bacteria to treat human solid tumors. This is based on the observation that various nonpathogenic anaerobic bacteria can infiltrate and replicate within solid tumors when given intravenously. Bacteria tested as potential anticancer agents include the Gram-positive obligate anaerobes Bifidobacterium and Clostridium, as well as the gram-negative facultative anaerobe Salmonella. Recent advances in synthetic biology and clinical success in cancer immunotherapy provide renewed momentum for developing bacteria-based cancer immunotherapy for cancer treatment and should allow greater potential for the development of novel therapeutic approaches for this devastating disease.

Comparative Efficacy of Selected Phytobiotics with Halquinol and Tetracycline on Gut Morphology, Ileal Digestibility, Cecal Microbiota Composition and Growth Performance in Broiler Chickens

Simple SummaryAntimicrobial growth promoters (AGPs) are banned in Europe but still used in many countries including Asia. However, their indiscriminate use resulted in antibiotic-resistant bacterial strains that possibly transfer the resistant genes to the microorganisms pertinent to human health. Hence, it is essential to find alternatives that can improve the production performance in broiler chickens. In this scenario, phytobiotics or phytogenic feed additives (PFAs) are widely investigated to evaluate their influence on improving gut health, increasing digestibility, and thereby the growth performance. The present study is a continuity of our experiments on dietary inclusion of Piper betle and Persicaria odorata leaf meal and the first of its kind to evaluate the comparative efficacy of phytobiotics (Piper betle and Persicaria odorata leaf meal), with halquinol and tetracycline in broiler chickens. The current experiment findings indicated that, in comparison with the control group, either of the dietary treatments positively modulated the gut morphology, improved ileal digestibility, maintained the intestinal population of Lactobacillus and reduced the pathogenic bacteria such as Staphylococcus aureus, Salmonella, Escherichia coli, and Clostridium spp., thus improved the growth performance in broiler chickens.The current experiment was designed to estimate the comparative efficacy of selected phytobiotics Persicaria odorata leaf meal (POLM) and Piper betle leaf meal (PBLM) with halquinol, and tetracycline in broiler chickens. The 150-day-old broiler chickens were randomly assigned to five dietary groups. The dietary supplementation groups were the basal diet (BD), which served as the negative control (NC), and BD + 0.2 g/kg tetracycline, which served as the positive control (PC); BD + 0.03 g/kg halquinol (HAL), BD + 8 g/kg POLM (Po8), and BD + 4 g/kg PBLM (Pb4) were the treatment groups. Growth performance, gut morphology, ileal digestibility, and cecal microbiota composition were measured. On day 21, the body weight gain (BWG) was enhanced (p < 0.05) in the broiler chickens fed on phytobiotics (Po8 and Pb4) relative to the NC group, however, on day 42 and in terms of overall growth performance, BWG was enhanced (p < 0.05 in diets (Po8, Pb4, HAL and PC) in comparison with the NC group. Conversely, feed conversion ratio (FCR) was recorded reduced (p < 0.05) in Pb4, Po8, HAL, and PC group in comparison with the NC group. Supplementation of phytobiotics (Po8 and Pb4), HAL and PC, positively improved the gut morphology compared to the NC group. Furthermore, the maximum (p < 0.05) villus height (VH) in duodenum and jejunum was observed in broilers fed on diet Pb4. Supplementation of phytobiotics, HAL and PC, improved (p < 0.05) the digestibility of dry matter (DM) (except for HAL), organic matter (OM), crude protein (CP), ether extract (EE), and ash compared to the NC group. Dietary supplementation of phytobiotics (Po8 and Pb4), HAL and PC, significantly reduced the E. coli, Salmonella, and Staphylococcus aureus (except for HAL) counts compared to the NC group. However, supplementation of Pb4 resulted in significantly decreased total anaerobic bacteria and Clostridium spp. counts compared to the NC group. In addition, supplementation of phytobiotics significantly increased the Lactobacillus count compared to HAL, PC, and NC groups. In conclusion, dietary supplementation of phytobiotics improved the gut morphology, positively modulated and maintained the dynamics of cecal microbiota with enhanced nutrient digestibility, thus, increased the growth performance. Based on current results, phytobiotics could be used as an alternative to AGPs for sustainable broiler chicken production.

Induced Production, Synthesis, and Immunomodulatory Action of Clostrisulfone, a Diarylsulfone from Clostridium acetobutylicum.

The anaerobe Clostridium acetobutylicum belongs to the most important industrially used bacteria. Whereas genome mining points to a high potential for secondary metabolism in C. acetobutylicum, the functions of most biosynthetic gene clusters are cryptic. We report that the addition of supra‐physiological concentrations of cysteine triggered the formation of a novel natural product, clostrisulfone (1). Its structure was fully elucidated by NMR, MS and the chemical synthesis of a reference compound. Clostrisulfone is the first reported natural product with a diphenylsulfone scaffold. A biomimetic synthesis suggests that pentamethylchromanol‐derived radicals capture sulfur dioxide to form 1. In a cell‐based assay using murine macrophages a biphasic and dose‐dependent regulation of the LPS‐induced release of nitric oxide was observed in the presence of 1.

Discovery and Biosynthesis of Clostyrylpyrones from the Obligate Anaerobe Clostridium roseum.

Anaerobic bacteria are a promising new source for natural product discovery. Examination of extracts from the obligate anaerobe Clostridium roseum led to the discovery of a new family of natural products, the clostyrylpyrones. The polyketide synthase-based biosynthetic mechanism of clostyrylpyrones is further proposed on the basis of bioinformatic, gene knockout, biochemical analysis, and heterologous expression studies.

INTERACTION OF OBLIGATE ANAEROBIC DESTROYER OF SOLID ORGANIC WASTE Clostridium butyricum GMP1 WITH SOLUBLE COMPOUNDS OF TOXIC METALS Cr(VI), Mo(VI) AND W(VI)

Increasing pollution of environment by toxic metals is the urgent problem requiring effective solution worldwide. The goal of the work was to study the dynamics of the interaction of Cr(VI), Mo(VI), W(VI) compounds with obligate anaerobic microorganisms Clostridium butyricum GMP1, which ferment organic compounds with the synthesis of hydrogen. The standard methods were used to determine рН and redox potential (Eh), the gas composition, and the concentration of metals. The application Clostridium butyricum GMP1 was showed to be useful to investigate its interaction with toxic metals. The higher redox potential of metal provided the opportunity for its faster and more effective reduction. The patterns of the reduction of toxic metals Cr(VI), Mo(VI) and W(VI) by obligate anaerobic strain Clostridium butyricum GMP1 were obtained. The experimental data confirmed the thermodynamically calculated correlation between the redox potential of the metal reduction to insoluble form and effectiveness of its removal. Obtained results can serve as the basis for further optimization and development of environmental biotechnologies for wastewater treatment with the simultaneous destruction of solid organic waste and hydrogen synthesis.