Microfiltration of Microbial Suspension

MEMBRANE ◽  
2020 ◽  
Vol 45 (1) ◽  
pp. 22-28
Author(s):  
Nobuyuki Katagiri
Keyword(s):  
Microbial Suspension

Antimicrobial Activity of Formylchromones: Detection by a Micro-Scale Method

2011 ◽  
Vol 66 (11-12) ◽  
pp. 562-570
Author(s):  
Markku Lehtinen ◽  
Eila Pelttari ◽  
Hannu Elo
Keyword(s):  
Antimicrobial Activity ◽  
High Throughput Screening ◽  
Test Substance ◽  
Minimal Inhibitory Concentrations ◽  
Micro Scale ◽  
Drug Candidates ◽  
Scale Method ◽  
Deep Well ◽  
Quinolone Antibiotics ◽  
Microbial Suspension

We report the antimicrobial activity of formylchromones. These compounds are remote structural analogues of nalidixic acid and quinolone antibiotics, and their activity was investigated by a simple micro-scale method designed for the determination of minimal inhibitory concentrations (MIC) of drug candidates and antibiotics against aerobic bacteria and yeasts. Minimal bactericidal and fungicidal concentrations (MBC and MFC, respectively) were also determined in connection with the MIC determinations. The results obtained were compared with those obtained using classical agar diffusion methodology. In the MIC method, deep-well micro-titration plates are used, covered by silicone sealing mats that allow diffusion of oxygen to the wells. The appropriate broth is pipetted into the wells, followed by a standardized microbial suspension (except for sterile controls) and a dilution series of the test substance or control antibiotic or a mere control solvent. The use of white nontransparent polypropylene plates allows easy visual inspection of microbial growth. For the MBC and MFC methods, samples are taken from all wells that contain a test substance or control antibiotic and do not display growth in the MIC test. The samples are streaked on agar plates, the liquid is allowed to absorb into the agar, and finally the microbes are spread all over the plate with a bent rod. Colony counts are compared with that of the untreated microbial suspension at the beginning of the MIC test. The MIC method is suitable for high-throughput screening

scholarly journals Phytate and Microbial Suspension Amendments Increased Soybean Growth and Shifted Microbial Community Structure

2021 ◽  
Vol 9 (9) ◽  
pp. 1803
Author(s):  
Bulbul Ahmed ◽  
Jean-Baptiste Floc’h ◽  
Zakaria Lahrach ◽  
Mohamed Hijri
Keyword(s):  
Community Structure ◽  
Microbial Community ◽  
Bacterial Community ◽  
Indicator Species ◽  
Mycorrhizal Fungi ◽  
Rrna Gene ◽  
Soybean Plant ◽  
Trichoderma Spp ◽  
Undisturbed Soil ◽  
Microbial Suspension

Phytate represents an organic pool of phosphorus in soil that requires hydrolysis by phytase enzymes produced by microorganisms prior to its bioavailability by plants. We tested the ability of a microbial suspension made from an old growth maple forest’s undisturbed soil to mineralize phytate in a greenhouse trial on soybean plants inoculated or non-inoculated with the suspension. MiSeq Amplicon sequencing targeting bacterial 16S rRNA gene and fungal ITS was performed to assess microbial community changes following treatments. Our results showed that soybean nodulation and shoot dry weight biomass increased when phytate was applied to the nutrient-poor substrate mixture. Bacterial and fungal diversities of the root and rhizosphere biotopes were relatively resilient following inoculation by microbial suspension; however, bacterial community structure was significantly influenced. Interestingly, four arbuscular mycorrhizal fungi (AMF) were identified as indicator species, including Glomus sp., Claroideoglomus etunicatum, Funneliformis mosseae and an unidentified AMF taxon. We also observed that an ericoid mycorrhizal taxon Sebacina sp. and three Trichoderma spp. were among indicator species. Non-pathogenic Planctobacteria members highly dominated the bacterial community as core and hub taxa for over 80% of all bacterial datasets in root and rhizosphere biotopes. Overall, our study documented that inoculation with a microbial suspension and phytate amendment improved soybean plant growth.

scholarly journals Improvement of Microbial Cell Concentration Technology in the Production of Live Plague Vaccine in the Form of Orodispersible Tablets

2021 ◽  
pp. 139-145
Author(s):  
D. A. Sharov ◽  
A. A. Leshchenko ◽  
S. V. Bagin ◽  
S. V. Logvinov ◽  
D. A. Mokhov ◽  
...  
Keyword(s):  
Comparative Study ◽  
Membrane Filtration ◽  
Cell Concentration ◽  
Submerged Cultivation ◽  
Bacterial Suspension ◽  
Microbial Cells ◽  
Native Culture ◽  
Technological Factors ◽  
Plague Vaccine ◽  
Microbial Suspension

The aim of the study was to improve the procedure for the Yersinia pestis EV strain cell concentration using the system for tangential flow microfiltration with the ASF-020 filter support unit.Materials and methods. The study used the vaccine Y. pestis EV strain derived from NIIEG cell line. Submerged cultivation of the native culture was performed using BIOR-0.25 reactor with automated control system. Microbial suspension concentrate was produced through microfiltration applying (Adaptive filtration system) AFS-009 and AFS-020 installations. The content of live microbial cells was determined by cytorefractometry. Assessment of the resistance of Y. pestis EV strain cells to technological factors was performed by photometric registration of changes in the optical density of bacterial suspension during the lytic response of cells to sodium dodecyl sulfate. Physical-chemical and immunobiological properties of the dry live plague vaccine were determined in accordance with the pharmacopoeial item.3.3.1.0021.15 of the State Pharmacopoeia of the Russian Federation, 14th edition.Results and discussion. The design features of the equipment introduced made it possible to carry out membrane filtration of microbial suspension, using BIOR-0.25 reactor as an intermediate storage unit, thereby excluding three technological stages. The total concentration of microbes in the suspension obtained by routine and improved methods was more than 150 billion microbial cells per ml. A comparative study of the effect of various hydrodynamic regimes in the working cavities of AFS-009 and AFS-020 filter units did not significantly affect the morphometric properties and resistance of microbial cultures to extreme (technological) factors. Based on the experimental data, the mass balance of the membrane filtration process has been determined. The optimized technology gave 0.13 liter yield of concentrate from 1 liter of native culture, and the process duration was reduced to 5 hours, the yield of the finished product in one production cycle was increased by 3 times. Thus, the process of concentrating Y. pestis EV strain cells during the production of the tablet form of live plague vaccine has been enhanced. A comparative study of the morphometric properties and resistance of plague microbe cultures to technological factors in the process of their concentration using optimized technology did not reveal any significant differences as compared to the routine one. Technological stage of concentrating has been reduced to 5 h term with a three-fold increase in the yield of finished product. 

scholarly journals Effect of soil-spraying time on root-colonization ability of antagonistic Streptomyces griseoviridis

1997 ◽  
Vol 6 (4) ◽  
pp. 341-348 ◽  
Author(s):  
Hanna Kortemaa ◽  
Kielo Haahtela ◽  
Aino Smolander
Keyword(s):  
Brassica Rapa ◽  
Daucus Carota ◽  
Soil Microbes ◽  
Root Colonization ◽  
Turnip Rape ◽  
Daucus Carota L ◽  
Streptomyces Griseoviridis ◽  
Colonization Ability ◽  
Antagonistic Streptomyces ◽  
Microbial Suspension

The root-colonization ability of Streptomyces griseoviridis Anderson et al. was tested on turnip rape (Brassica rapa subsp. oleifera DC.) and carrot (Daucus carota L.) by the sand-tube method. Nonsterile sand was sprayed with a microbial suspension immediately or 7 days after the seed had been sown. Results expressed as population frequencies and densities indicated that S. griseoviridis effectively colonizes the rhizosphere when the microbe is applied immediately after sowing but less effectively when it is applied 7 days later. Detection values of S. griseoviridis were higher for turnip rape than for carrot. In sterile sand, S. griseoviridis invaribly colonized the rhizosphere of turnip rape after each of the two applications. These findings indicate that S. griseoviridis can compete with indigenous soil microbes in the rhizosphere if it is sufficiently abundant in the soil before the seed emerges. If applied later, however, it competes rather poorly. In root-free nonsterile sand, S. griseoviridis dispersed and survived well.

scholarly journals A Microfluidic Device for Imaging Samples from Microbial Suspension Cultures

MethodsX ◽  
2020 ◽  
Vol 7 ◽  
pp. 100891
Author(s):  
Alexander Letourneau ◽  
Jack Kegel ◽  
Jehad Al-Ramahi ◽  
Emily Yachinich ◽  
Harris B. Krause ◽  
...  
Keyword(s):  
Microfluidic Device ◽  
Suspension Cultures ◽  
Microbial Suspension

STIMULATORY EFFECT OF DL-3-HYDROXYBUTYRATE ON OXYGEN UPTAKE OF PERFUSED OMASAL LEAF

1984 ◽  
Vol 64 (5) ◽  
pp. 273-275 ◽  
Author(s):  
B. EMMANUEL ◽  
F. J. LOZEMAN ◽  
L. P. MILLIGAN
Keyword(s):  
Electron Transfer ◽  
Oxygen Uptake ◽  
Key Words ◽  
Rumen Microorganisms ◽  
Rumen Epithelium ◽  
Perfusion Chamber ◽  
Microbial Suspension

Oxygen uptake by the perfused omasal leaf was measured in the presence of mixed rumen microbial suspension which was kept anaerobically in the lumen side of a perfusion chamber. The addition of DL-3-hydroxybutyrate at 2, 4 and 8 mM concentrations to the microbial suspension increased oxygen withdrawal by 4.4, 11.1 and 15.5%, respectively. It is proposed that electron transfer through the coupled D(−)-3-hydroxybutyrate-acetoacetate reaction from rumen microorganisms to rumen epithelium yield energy for the latter tissue. Key words: Omasal leaf, oxygen uptake, microbes, DL-3-hydroxybutyrate

Antimicrobial Activity of Chlorhexidine against Multi-Species Biofilm Formation

2017 ◽  
Vol 899 ◽  
pp. 237-242
Author(s):  
Ana Lucia do Amaral Escada ◽  
Cristiane Aparecida Pereira ◽  
Antonio Olavo Cardoso Jorge ◽  
Ana Paula Rosifini Alves Claro
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Bacterial Adhesion ◽  
Biofilm Formation ◽  
Brain Heart Infusion ◽  
Physiological Solution ◽  
Bacterial Biofilm ◽  
Selective Agar ◽  
Microbial Suspension ◽  
Scanning Electron

In the present work, the efficacy of the Ti–7.5Mo alloy nanotube and Ti–7.5Mo alloy nanotube with chlorhexidine against bacterial biofilm formation was evaluated. Nanotubes were processed using anodization in 0.25% NH4F electrolyte solution. Biofilms were cultured in discs immersed in sterile brain heart infusion broth (BHI) containing 5% sucrose, inoculated with microbial suspension (106 cells/ml) and incubated for 5 days. Next, the discs were placed in tubes with sterile physiological solution 0.9% sodium chloride (NaCl) and sonicated to disperse the biofilms. Tenfold serial dilutions were carried and aliquots seeded in selective agar, which were then incubated for 48 h. Then, the numbers CFU/ml (log 10) were counted and analyzed statistically. Scanning electron microscopy (SEM) on discs with biofilms groups and contact angle was carried out. The results show that there is no difference in bacterial adhesion between of the Ti–7.5Mo alloy nanotube and Ti–7.5Mo alloy nanotube with chlorhexidine.

4-Hydroxycyclohexanecarboxylic Acid as a Substrate for Cyclohexanecarboxylic Acid Production during the “Zapatera” Spoilage of Spanish-Style Green Table Olives

1996 ◽  
Vol 59 (6) ◽  
pp. 657-662 ◽  
Author(s):  
ALFREDO MONTAÑO ◽  
ANTONIO de CASTRO ◽  
LUIS REJANO ◽  
MANUEL BRENES
Keyword(s):  
Lactic Acid ◽  
Acid Production ◽  
Synthetic Medium ◽  
Lactic Acid Fermentation ◽  
Table Olives ◽  
Acid Fermentation ◽  
Cyclohexanecarboxylic Acid ◽  
Green Olive ◽  
Microbial Suspension

Zapatera spoilage was reproduced in Spanish-style green olive brines adjusted to pH 5 and with a concentration of 5% (wt/vol) NaCl. A relationship between the formation of the compound responsible for the zapatera off odor, cyclohexanecarboxylic acid, and consumption of a new compound isolated from olive brines, 4-hydroxycyclohexanecarboxylic acid, was established. When the latter compound was added to a synthetic medium inoculated with a concentrated microbial suspension from a zapatera brine, cyclohexanecarboxylic acid was formed. 4-Hydroxy-cyclohexanecarboxylic acid was not detected in fresh olives, NaOH solutions, or water washes. In normal fermentation brines it was not detected after 30 days of brining, its concentration increasing in a progressive manner thereafter during typical lactic acid fermentation of Spanish-style green olives.

scholarly journals Effect of microbial feed additives on growth performance, microbial protein synthesis, and rumen microbial population in growing lambs

2020 ◽  
Vol 4 (4) ◽  
Author(s):  
Ehsan Direkvandi ◽  
Tahereh Mohammadabadi ◽  
Abdelfattah Z M Salem
Keyword(s):  
Body Weight ◽  
Protein Synthesis ◽  
Growth Performance ◽  
Microbial Population ◽  
Feed Additives ◽  
Bacterial Suspension ◽  
Microbial Protein ◽  
Microbial Protein Synthesis ◽  
Degrading Bacteria ◽  
Microbial Suspension

Abstract Arabi lambs (n =28; body weight = 24 ± 3.7 kg; average age = 120 ± 8 days) were used to investigate the effect of microbial additives on growth performance, microbial protein synthesis and rumen microbial population of fattening lamb based on completely randomized design. Four treatments were studied: (1) control (without additive; CON); (2) Lactobacillus fermentum and L. plantarum (FP); (3) Saccharomyces cerevisiae (SC) plus FP (SCFP); and (4) Megasphaera elsdenii plus SCFP (MSCFP). Lambs were inoculated before morning feeding (daily oral dosed) with a 50 mL microbial suspension as follows: FP, 50 mL bacterial suspension containing 4.5 × 108 colony-forming unit per day (cfu/d) of L. plantarum and L. fermentum (in ratio 50:50); SCFP, 50 mL microbial suspension containing 4.5 × 108 cfu/d FP and 1.4 × 1010 cfu/d SC; MSCFP, 50 mL microbial suspension containing 4.5 × 108 cfu/d Me, 4.5 × 108 cfu/d FP and 1.4 × 1010 cfu/d SC. Feed intake and body weight of lambs were not affected by microbial additives. Average daily gain and feed efficiency were increased on day 0 to 21. The highest concentration of uric acid, total excreted purine derivatives (PD), microbial N, microbial CP, and metabolizable protein were in MSCFP lambs. The ruminal population of Ruminococcus albus and Ruminococcus flavefaciens was higher in MSCFP and SCFP than CON and FP lambs. The highest and the lowest abundance of M. elsdenii and methanogen respectively was observed in lambs fed on microbial additives. The tendency to improve growth performance vs. CON may be due to improvements in microbial protein synthesis and microbial populations, especially fiber-degrading bacteria. The decrease in the population of methanogens as a result of the use of microbial additives is another positive result.

Sign in / Sign up

Export Citation Format

Share Document