Ammonium-oxidizing bacteria facilitate aerobic degradation of sulfanilic acid in activated sludge

2014 ◽  
Vol 70 (6) ◽  
pp. 1122-1128 ◽  
Author(s):  
Gang Chen ◽  
Maneesha P. Ginige ◽  
Anna H. Kaksonen ◽  
Ka Yu Cheng
Keyword(s):  
Activated Sludge ◽  
Oxygen Uptake Rate ◽  
Substrate Inhibition ◽  
Inhibitory Effect ◽  
Sulfanilic Acid ◽  
Ammonium Concentration ◽  
Microbial Culture ◽  
High Concentration ◽  
Mixed Microbial Culture ◽  
First Time

Sulfanilic acid (SA) is a toxic sulfonated aromatic amine commonly found in anaerobically treated azo dye contaminated effluents. Aerobic acclimatization of SA-degrading mixed microbial culture could lead to co-enrichment of ammonium-oxidizing bacteria (AOB) because of the concomitant release of ammonium from SA oxidation. To what extent the co-enriched AOB would affect SA oxidation at various ammonium concentrations was unclear. Here, a series of batch kinetic experiments were conducted to evaluate the effect of AOB on aerobic SA degradation in an acclimatized activated sludge culture capable of oxidizing SA and ammonium simultaneously. To account for the effect of AOB on SA degradation, allylthiourea was used to inhibit AOB activity in the culture. The results indicated that specific SA degradation rate of the mixed culture was negatively correlated with the initial ammonium concentration (0–93 mM, R2 = 0.99). The presence of AOB accelerated SA degradation by reducing the inhibitory effect of ammonium (≥10 mM). The Haldane substrate inhibition model was used to correlate substrate concentration (SA and ammonium) and oxygen uptake rate. This study revealed, for the first time, that AOB could facilitate SA degradation at high concentration of ammonium (≥10 mM) in an enriched activated sludge culture.

Kinetics of growth and multi substrate degradation by an indigenous mixed microbial culture isolated from a wastewater treatment plant in Guwahati, India

2008 ◽  
Vol 58 (5) ◽  
pp. 1101-1106
Author(s):  
Pichiah Saravanan ◽  
K. Pakshirajan ◽  
P. K. Saha
Keyword(s):  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Lag Phase ◽  
Microbial Culture ◽  
High Concentration ◽  
Mixed Microbial Culture ◽  
Phenol Biodegradation ◽  
Low Concentration ◽  
Culture Growth

An indigenous mixed culture of microorganisms, isolated from a sewage treatment plant, was investigated for its potential to simultaneously degrade phenol and m-cresol during its growth in batch shake flasks. 22 full factorial designs with the two substrates as the factors, at two different levels and two different initial concentration ranges, were employed to carry out the biodegradation experiments. For complete utilisation of phenol and m-cresol, the culture took a minimum duration of 21 hrs at their low concentration of 100 mg/L each, and a maximum duration of 187 hrs at high concentration of 600 mg/L each in the multisubstrate system. The biodegradation results also showed that the presence of phenol in low concentration range (100–300 mg/L did not inhibit m-cresol biodegradation; on the other hand, presence of m-cresol inhibited phenol biodegradation by the culture. Moreover, irrespective of the concentrations used, phenol was degraded preferentially and earlier than m-cresol. During the culture growth, a lag phase was observed above a combined concentration of 500 mg/L i.e., 200 mg/L m-cresol and 300 mg/L of phenol and above). Statistical analysis of the specific growth rate of the culture in the multisubstrate system was also performed in the form of ANOVA and Student ‘t’ test, which gave good interpretation in terms of main and interaction effects of the substrates.

Effects of phenol on sulfate reduction by mixed microbial culture: kinetics and bio-kinetics analysis

2017 ◽  
Vol 77 (4) ◽  
pp. 1079-1088 ◽  
Author(s):  
Mohit Prakash Mohanty ◽  
Bharati Brahmacharimayum ◽  
Pranab Kumar Ghosh
Keyword(s):  
Sulfate Reduction ◽  
Microbial Growth ◽  
Substrate Inhibition ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Kinetic Studies ◽  
Microbial Culture ◽  
Mixed Microbial Culture ◽  
Kinetic Coefficients ◽  
Institute Of Technology

Abstract Mixed microbial culture collected from the wastewater treatment plant of Indian Institute of Technology Guwahati (IITG) was further grown in anaerobic condition in presence of sulfate where lactate was added as a carbon source. Sulfate addition was increased stepwise up to 1,000 mg l−1 before phenol was added at increasing concentrations from 10 mg l−1 to 300 mg l−1. Kinetics of sulfate, phenol and chemical oxygen demand reduction were studied and experimental findings were analyzed using various bio-models to estimate the bio-kinetic coefficients. This is the first detailed report on kinetics and bio-kinetic studies of sulfate reduction in presence of phenol. Experimental results showed that there was no inhibition of sulfate reduction and microbial growth up to 100 mg l−1 phenol addition. However, inhibition to different degrees was observed at higher phenol addition. The experimental data of microbial growth and substrate consumption in presence of phenol fitted well to the Edward model (R2 = 0.85, root mean square error = 0.001011) with maximum specific growth rate = 0.052 h−1, substrate inhibition constant = 88.05 mg l−1 and half saturation constant = 58.22 mg l−1. The characteristics of the cultured microbes were determined through a series of analysis and microbial tests.

scholarly journals Blends of Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) with Fruit Pulp Biowaste Derived Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate-co-3-Hydroxyhexanoate) for Organic Recycling Food Packaging

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1155
Author(s):  
Beatriz Meléndez-Rodríguez ◽  
Sergio Torres-Giner ◽  
Maria A. M. Reis ◽  
Fernando Silva ◽  
Mariana Matos ◽  
...  
Keyword(s):  
Food Packaging ◽  
Mechanical Response ◽  
Cost Effective ◽  
Single Step ◽  
Microbial Culture ◽  
Crystalline Morphology ◽  
Mixed Microbial Culture ◽  
Brittle To Ductile Transition ◽  
Extraction And Purification ◽  
First Time

In the present study, a new poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate) [P(3HB-co-3HV-co-3HHx)] terpolyester with approximately 68 mol% of 3-hydroxybutyrate (3HB), 17 mol% of 3-hydroxyvalerate (3HV), and 15 mol% of 3-hydroxyhexanoate (3HHx) was obtained via the mixed microbial culture (MMC) technology using fruit pulps as feedstock, a processing by-product of the juice industry. After extraction and purification performed in a single step, the P(3HB-co-3HV-co-3HHx) powder was melt-mixed, for the first time, in contents of 10, 25, and 50 wt% with commercial poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Thereafter, the resultant doughs were thermo-compressed to obtain highly miscible films with good optical properties, which can be of interest in rigid and semirigid organic recyclable food packaging applications. The results showed that the developed blends exhibited a progressively lower melting enthalpy with increasing the incorporation of P(3HB-co-3HV-co-3HHx), but retained the PHB crystalline morphology, albeit with an inferred lower crystalline density. Moreover, all the melt-mixed blends were thermally stable up to nearly 240 °C. As the content of terpolymer increased in the blends, the mechanical response of their films showed a brittle-to-ductile transition. On the other hand, the permeabilities to water vapor, oxygen, and, more notably, limonene were seen to increase. On the overall, this study demonstrates the value of using industrial biowaste derived P(3HB-co-3HV-co-3HHx) terpolyesters as potentially cost-effective and sustainable plasticizing additives to balance the physical properties of organic recyclable polyhydroxyalkanoate (PHA)-based food packaging materials.

scholarly journals Kinetic modelling for removal of m-cresol from wastewater using mixed microbial culture in batch reactor

2012 ◽  
Vol 2 (3) ◽  
pp. 149-156 ◽  
Author(s):  
Sudipta Dey ◽  
Somnath Mukherjee
Keyword(s):  
Kinetic Modelling ◽  
Batch Reactor ◽  
Substrate Inhibition ◽  
Coke Oven ◽  
Effluent Treatment ◽  
Yield Coefficient ◽  
Microbial Culture ◽  
Mixed Microbial Culture ◽  
Good Potential ◽  
Inhibitory Type

An indigenous mixed microbial culture isolated from an effluent treatment section of a coke oven plant has been studied for its m-cresol biodegradation capacity under aerobic batch reactor operation. The culture, after acclimatization could biodegrade up to 700 mg/L of m-cresol. The m-cresol concentration in the present study was at 50 mg/L and then ranged from 100 to 700 mg/L with step up concentration of 100 mg/L. Both biodegradation kinetics and microorganism growth kinetics were studied and kinetic parameters were estimated. The result showed that m-cresol was an inhibitory-type substrate and the inhibition effect became predominant after 200 mg/L of initial m-cresol. The specific growth rate of microorganisms increased up to 200 mg/L of m-cresol as sole carbon source, and then started decreasing. The kinetic data obtained in this study have been fitted to different substrate inhibition models (Haldane, Han-Levenspiel, Edward, Luong, Aiba, Teissier, Yano-Koga). Among all models, Han-Levenspiel and Luong were best fitted for this study (root mean square error = 0.001349). In addition, the variation of observed yield coefficient Yx/s with initial m-cresol concentration was investigated. The values of kinetic constants estimated by the models proved that the mixed culture used in the study had good potential for m-cresol degradation.

Measurement of the Platelet Response to Laser- induced Microvascular Injury

1974 ◽  
Vol 32 (02/03) ◽  
pp. 704-713 ◽  
Author(s):  
F. N McKenzie ◽  
K.-E Arfors ◽  
N. A Matheson
Keyword(s):  
Inhibitory Effect ◽  
Microvascular Blood Flow ◽  
Platelet Response ◽  
High Concentration ◽  
Platelet Activity ◽  
Microvascular Injury ◽  
Arterial Blood ◽  
Proximal Site ◽  
Adenosine Phosphates

SummaryA study has been made of the biochemical factors underlying the platelet response to laser-induced microvascular injury. A platelet aggregating substance is produced at sites of laser-induced injury which markedly stimulates platelet activity at a site of injury inflicted a short distance downstream. Distal sites of injury are not similarly influenced if the distance between the injuries is increased or if the proximal site no longer shows platelet-stimulating activity. The stimulating effect of an adjacent proximal injury on platelet activity at a distal site is inhibited by local intra-arterial infusion of adenosine. Measurements of arterial blood pressure and microvascular blood flow velocity during adenosine infusion showed that its inhibitory effect on platelet activity is largely independent of its vasodilator properties. The effect of infusion of different adenosine phosphates (AMP, ADP, ATP) was also studied. Very small amounts of ADP markedly stimulated platelet activity and the emboli formed were similar to those normally produced at sites of laser injury. At high concentration AMP inhibited while ATP stimulated platelet activity in vivo. The results emphasise the fundamental role of ADP as a mediator of the platelet response at sites of laser- induced microvascular injury.

Effect of nickel(II) on the biomass yield of the activated sludge

1996 ◽  
Vol 34 (5-6) ◽  
pp. 163-171 ◽  
Author(s):  
Celal F. Gökçay ◽  
Ulku Yetis
Keyword(s):  
Activated Sludge ◽  
Decay Constant ◽  
Biomass Yield ◽  
Culture Conditions ◽  
Synthetic Wastewater ◽  
Base Line ◽  
Microbial Culture ◽  
Feed Composition ◽  
Steady State Condition ◽  
Applied Microbiology

Biomass yield of microorganisms is important in applied microbiology since it is the ultimate factor determining the amount of product produced regardless of whether product is growth-linked or not. In the case of environmental microbiology the opposite is true and minimizing the biomass produced, or the sludge in the relevant jargon, often is the prime goal. In this paper, a unique means of manipulating the microbial biomass yield of a heterogeneous culture to fulfil either of the two goals is presented. 5.0 mgl−1 Ni(II) in the feed composition to a completely mixed, once- through, activated sludge was found to induce the observed biomass yield of the microbial culture developed from sewage. As compared with the base-line study without Ni(II), where the reactor received synthetic wastewater only, true biomass yield was found to have increased along with the increased decay constant with the net effect of lowering observed biomass yield drastically at lower dilution rates and increasing it over that observed in the base-line study at higher dilution rates. At 10.0 mgl−1 influent Ni(II) concentration the culture conditions almost reverted back to the base- line study and at 25 mgl−1 Ni(II) concentration a truly steady-state condition could not be attained.

Minimization of activated sludge production by chemically stimulated energy spilling

2000 ◽  
Vol 42 (12) ◽  
pp. 189-200 ◽  
Author(s):  
G.-H. Chen ◽  
H.-K. Mo ◽  
S. Saby ◽  
W.-k. Yip ◽  
Y. Liu
Keyword(s):  
Activated Sludge ◽  
Growth Yield ◽  
Dry Weight ◽  
Staining Technique ◽  
Microbial Culture ◽  
Dapi Staining ◽  
E Coli ◽  
Energy Spilling ◽  
Activated Sludge Processes ◽  
Sludge Production

Minimization of excess sludge production in activated sludge processes has been pursued around the world in order to meet stringent environmental regulations on sludge treatment and disposal. To achieve this goal, physical, chemical, and biological approaches have been proposed. In this paper, a chemical compound, 3,3′,4′,5-tetrachlorosalicylanilide (TCS) was tested for enhancing microbial energy spilling of the sludgeso as to minimize its growth. In order to examine this, an exploratory study was conducted using both batch and continuous activated sludge cultures. Batch experiments with these two cultures were carried out at different initial concentrations of TCS. It has been confirmed that an addition of TCS is effective in reducing the production of both the sludge cultures, particularly the continuous culture where the observed growth yield was reduced by around 70%, when the initial TCS concentration was 0.8 ppm. Meanwhile, the substrate removal activity of this culture was found not to be affected at this TCS concentration. To further evaluate the TCS effect, a pure microbial culture of E. coli was employed. Batch experiment results with this culture implied that TCS might be able to reduce the cell density of E. coli drastically when an initial TCS concentration was greater than 0.12 ppm. It was also found that TCS was not toxic to this type of bacteria. Microscopic examinations with a 4′, 6-diamidino-2-phenylindole (DAPI) staining technique revealed that TCS neither affected the cell division nor altered the cell size of E. coli. However, both the cell ATP content and the cell dry weight were reduced significantly with the addition of TCS.

Characterization of Nostoc muscorum NCCU-442 Derived Poly-3- hydroxybutyrate (PHB) and Polyethylene Glycol (PEG) Blends

2020 ◽  
Vol 10 (3) ◽  
pp. 200-207
Author(s):  
Sabbir Ansari ◽  
Tasneem Fatma
Keyword(s):  
Thermal Properties ◽  
Polyethylene Glycol ◽  
Morphological Properties ◽  
Morphological Alteration ◽  
Nostoc Muscorum ◽  
Microbial Culture ◽  
Polymer Science ◽  
Mixed Microbial Culture ◽  
Scanning Calorimetry ◽  
Casting Technique

Background: Poly-3-hydroxybutyrate (PHB) has attracted much consideration as biodegradable biocompatible polymer. This thermoplastic polymer has comparable material properties to polypropylene. Materials with more valuable properties may result from blending, a common practice in polymer science. Objective: In this paper, blends of PHB (extracted from cyanobacterium Nostoc muscorum NCCU- 442 with polyethylene glycol (PEG) were investigated for their thermal, tensile, hydrophilic and biodegradation properties. Methods: Blends were prepared in different proportions of PHB/PEG viz. 100/0, 98/2, 95/5, 90/10, 80/20, and 70/30 (wt %) using solvent casting technique. Morphological properties were investigated by using Scanning Electron Microscopy (SEM). Differential scanning calorimetry and thermogravimetric analysis were done for thermal properties determination whereas the mechanical and hydrophilic properties of the blends were studied by means of an automated material testing system and contact angle analyser respectively. Biodegradability potential of the blended films was tested as percent weight loss by mixed microbial culture within 60 days. Results: The blends showed good misciblity between PEG and PHB, however increasing concentrations of plasticizer caused morphological alteration as evidenced by SEM micrographs. PEG addition (10 % and above) showed significant alternations in the thermal properties of the blends. Increase in the PEG content increased the elongation at break ratio i.e enhanced the required plasticity of PHB. Rate of microbial facilitated degradation of the blends was greater with increasing PEG concentrations. Conclusion: Blending with PEG increased the crucial polymeric properties of cyanobacterial PHB.

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