Isolation, Identification and Characterization of Bioflocculant-Producing Bacteria from Activated Sludge of Vulindlela Wastewater Treatment Plant

The low microbial flocculant yields and efficiencies limit their industrial applications. There is a need to identify bacteria with high bioflocculant production. The aim of this study was to isolate and identify a bioflocculant-producing bacterium from activated sludge wastewater and characterise its bioflocculant activity. The identification of the isolated bacterium was performed by 16S rRNA gene sequencing analysis. The optimal medium composition (carbon and nitrogen sources, cations and inoculum size) and culture conditions (temperature, pH, shaking speed and time) were evaluated by the one-factor-at-a-time method. The morphology, functional groups, crystallinity and pyrolysis profile of the bioflocculant were analysed using scanning electron microscope (SEM), Fourier transform infrared (FTIR) and thermogravimetric (TGA) analysis. The bacterium was identified as Proteus mirabilis AB 932526.1. Its optimal medium and culture conditions were: sucrose (20 g/L), yeast extract (1.2 g/L), MnCl2 (1 g/L), pH 6, 30 °C, inoculation volume (3%), shaking speed (120 rpm) for 72 h of cultivation. SEM micrograph revealed the bioflocculant to be amorphous. FTIR analysis indicated the presence of hydroxyl, carboxyl and amino groups. The bioflocculant was completely pyrolyzed at temperatures above 800 °C. The bacterium has potential to produce bioflocculant of industrial importance.

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Production and Characterization of a Novel Bioflocculant from Bacillus licheniformis

Applied and Environmental Microbiology ◽

10.1128/aem.02558-09 ◽

2010 ◽

Vol 76 (9) ◽

pp. 2778-2782 ◽

Cited By ~ 100

Author(s):

Yuyan Xiong ◽

Yuanpeng Wang ◽

Yi Yu ◽

Qingbiao Li ◽

Haitao Wang ◽

...

Keyword(s):

Bacillus Licheniformis ◽

16S Rrna Gene Sequencing ◽

Amino Sugar ◽

Culture Conditions ◽

Inoculum Size ◽

Infrared Spectrometry ◽

Rrna Gene ◽

Neutral Sugar ◽

Sem Images ◽

Average Mass

ABSTRACT A bacterium producing an extracellular bioflocculant was isolated from contaminated LB medium and identified as Bacillus licheniformis by 16S rRNA gene sequencing and its biochemical/physiological characteristics. The optimum culture conditions for flocculant production were an initial medium pH of 7.2 and an inoculum size of 4% (vol/vol). The maximum flocculating activity (700 U/ml) was obtained after cultivation at 37°C for 48 h. Chemical analyses of the purified bioflocculant revealed that it was a proteoglycan composed of 89% carbohydrate and 11% protein (wt/wt). The mass ratio of neutral sugar, amino sugar, and uronic acid was measured at 7.9:4:1. Infrared spectrometry further indicated the presence of carboxyl, hydroxyl, and amino groups, typical of heteropolysaccharide. The average mass of the bioflocculant was calculated to be 1.76 × 106 Da. Scanning electron microscopy (SEM) images of the bioflocculant showed an irregular structure with netted texture. Its efficient flocculation capabilities suggest potential applications in industry.

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Modeling and Statistical Optimization of Culture Conditions for Improvement of Antifungal Compounds Production by Streptomyces albidoflavus S19 Strain of Wastewater Origin

Anti-Infective Agents ◽

10.2174/2211352516666180813102424 ◽

2018 ◽

Vol 17 (1) ◽

pp. 39-49 ◽

Cited By ~ 3

Author(s):

S. Souagui ◽

W. Djoudi ◽

H. Boudries ◽

M. Béchet ◽

V. Leclére ◽

...

Keyword(s):

Response Surface Methodology ◽

Antifungal Activity ◽

Response Surface ◽

Ph Value ◽

16S Rrna Gene Sequencing ◽

Culture Conditions ◽

Rrna Gene ◽

Sequencing Analysis ◽

Promising Alternative ◽

Antifungal Metabolites

Background: The actinomycetes strains isolated from unexplored ecosystems are a promising alternative for the biosynthesis of novel antimicrobial compounds. Depending on the interesting antifungal activity of the studied strain S19, the statistical method seems to be an effective tool for optimizing the production of anticandidal molecules. Introduction: This study was conducted in order to optimize the culture parameters (medium nutrients concentrations and initial pH value) affecting the production of antifungal metabolites from S. albidoflavus strain S19 (obtained from wastewater collected in Bejaia region, Algeria) using Response Surface Methodology (RSM). The best conditions for anti-Candida albicans compounds biosynthesis were determined. Methods and Results: The antimicrobial producer strain S. albidoflavus S19 was identified on the basis of morphological, chemicals characters and physiological characteristics along with 16S rRNA gene sequencing analysis. Response Surface Methodology by Central Composite Design (CCD) was employed to improve the anti- C. albicans agents production through the optimization of medium parameters. The highest antifungal activity was obtained by using a mixture of 2g l-1 starch, 4g l-1 yeast extract, 2g l-1 peptone at pH 11. Conclusion: The strain S19 isolated from wastewater showed a significant anti-C. albicans activity and this study revealed the effectiveness of RSM and CCD for increasing bioactive compounds production, rising the diameter of inhibition zones from 13 to 34 mm.

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Isolation and Optimization of Culture Conditions of a Bioflocculant-Producing Fungi from Kombucha Tea SCOBY

Microbiology Research ◽

10.3390/microbiolres12040070 ◽

2021 ◽

Vol 12 (4) ◽

pp. 950-966

Author(s):

Phakamani H. Tsilo ◽

Albertus K. Basson ◽

Zuzingcebo G. Ntombela ◽

Tsolanku S. Maliehe ◽

Rajasekhar V. S. R. Pullabhotla

Keyword(s):

Nitrogen Sources ◽

Xrd Analysis ◽

Culture Conditions ◽

Inoculum Size ◽

Medium Composition ◽

Rrna Gene ◽

Environmental Friendliness ◽

Pichia Kudriavzevii ◽

Kombucha Tea ◽

Ft Ir

Biolocculants are gaining attention in research due to their environmental friendliness and innocuousness to human in comparison to the conventional flocculants. The present study aimed to investigate the ability of fungi from Kombucha tea SCOBY to produce effective bioflocculant in bulk. A 16S rRNA gene sequence analysis was utilized to identify the isolate. The medium composition (carbon and nitrogen sources) and culture conditions (inoculum size, temperature, shaking speed, pH, and time) were optimized using one-factor-at-a-time method. The functional groups, morphology, and crystallinity of the bioflocculant were evaluated using Fourier transform infrared (FT-IR), scan electron microscope (SEM) and X-ray diffractometry (XRD). The fungus was found to be Pichia kudriavzevii MH545928.1. It produced a bioflocculant with flocculating activity of 99.1% under optimum conditions; 1% (v/v) inoculum size, glucose and peptone as nutrient sources, 35 °C, pH 7 and the shaking speed of 140 rpm for 60 h. A cumulus-like structure was revealed by SEM; FT-IR displayed the presence of hydroxyl, carboxyl, amine, and thiocynates. The XRD analysis demonstrated the bioflocculant to have big particles with diffraction peaks at 10° and 40° indicating its crystallinity. Based on the obtained results, P. kudriavzevii MH545928.1 has potential industrial applicability as a bioflocculant producer.

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First case of an invasive Bacteroides dorei infection detected in a patient with a mycotic aortic aneurysm—raising a rebellion of major indigenous bacteria in humans: a case report and review

BMC Infectious Diseases ◽

10.1186/s12879-021-06345-8 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Takayuki Matsuoka ◽

Takuya Shimizu ◽

Tadanori Minagawa ◽

Wakiko Hiranuma ◽

Miki Takeda ◽

...

Keyword(s):

Aortic Aneurysm ◽

16S Rrna ◽

16S Rrna Gene ◽

Gene Sequencing ◽

16S Rrna Gene Sequencing ◽

Resected Specimen ◽

Rrna Gene ◽

Sequencing Analysis ◽

First Case ◽

Rrna Gene Sequencing

Abstract Background Bacteroides dorei is an anaerobic gram-negative bacterium first described in 2006. Because of the high similarity in mass spectra between B. dorei and Bacteroides vulgatus, discriminating between these species is arduous in clinical practice. In recent decades, 16S rRNA gene sequencing has been a complementary method for distinguishing taxonomically close bacteria, including B. dorei and B. vulgatus, at the genus and species levels. Consequently, B. dorei has been shown to contribute to some diseases, including type 1 autoimmune diabetes mellitus and atherosclerotic diseases. However, there are no reports on invasive infectious diseases caused by B. dorei. This report describes the first case of direct invasion and colonisation of human tissue by B. dorei, thus providing a warning regarding the previously proposed application of B. dorei as a live biotherapeutic for atherosclerotic diseases. Case presentation A 78-year-old Japanese man complained of intermittent chest/back pain and was diagnosed with a mycotic thoracic aortic aneurysm by enhanced computed tomography on admission. Despite strict blood pressure control and empirical antibiotic therapy, the patient’s condition worsened. To prevent aneurysmal rupture and eliminate infectious foci, the patient underwent surgical treatment. The resected specimen was subjected to tissue culture and 16S rRNA gene sequencing analysis to identify pathogenic bacteria. A few days after the surgery, culture and sequencing results revealed that the pathogen was B. dorei/B. vulgatus and B. dorei, respectively. The patient was successfully treated with appropriate antibacterial therapy and after improvement, was transferred to another hospital for rehabilitation on postoperative day 34. There was no recurrence of infection or aneurysm after the patient transfer. Conclusions This report describes the first case of invasive infectious disease caused by B. dorei, casting a shadow over its utilisation as a probiotic for atherosclerotic diseases.

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Determination of important enzymes and antimicrobial resistances of gram-positive haloalkaliphilic bacteria isolated from Salda Lake

Ege Journal of Fisheries and Aquatic Sciences ◽

10.12714/egejfas.38.3.14 ◽

2021 ◽

Vol 38 (3) ◽

pp. 375-382

Author(s):

Pınar Çağlayan

Keyword(s):

Bacillus Subtilis ◽

Soda Lakes ◽

Soda Lake ◽

16S Rrna Gene Sequencing ◽

Extreme Environment ◽

Rrna Gene ◽

Sequencing Analysis ◽

Haloalkaliphilic Bacteria ◽

Rrna Gene Sequencing

As an extreme environment, soda lakes harbor various haloalkaliphilic microorganisms. Salda Lake is one of the natural soda lake (pH˃9) in Turkey. Haloalkaliphiles are unique microorganisms in their ability to live in high alkaline and high saline conditions, and play an important role in biodegradation and bioremediation of hydrocarbons. Hence, the aims of this study were to isolate haloalkaliphilic bacteria from water sample of Salda Lake, to identify these isolates by both conventional and molecular methods, to screen their industrially important enzymes, and to investigate their antimicrobial resistance profiles. Six isolates were identified as Bacillus horneckiae, Bacillus subtilis, Bacillus paramycoides, Bacillus pumilus, Staphylococcus epidermidis, Bacillus haynesii according to 16S rRNA gene sequencing analysis. The industrially important enzymes (amylase, cellulase, pullulanase, lipase, urease, protease, caseinase, oxidase, catalase) were produced by haloalkaliphilic isolates. These enzymes maybe used in alkaline and saline industrial processes. Although Bacillus subtilis was susceptible to all antibiotics, other isolates showed resistance to at least one antibiotic. The resistance against antibiotics were found as ampicillin/sulbactam 83%, amoxycillin/clavulanic acid 83%, ampicillin 67%, mupirocin 67%, chloramphenicol 50%, tetracycline 50%, imipenem 50%, meropenem 50%, cefadroxil 17%. These bacteria may have develope resistance to antibiotics that entering their natural environment in different ways.

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Comparative Study on Rate of Biodegradation of Diluted Bitumen and Conventional Oil in Fresh Water

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-2017.1.2256 ◽

2017 ◽

Vol 2017 (1) ◽

pp. 2256-2267

Author(s):

Ruta Suresh Deshpande ◽

Devi Sundaravadivelu ◽

Pablo Campo ◽

Jorge W. SantoDomingo ◽

Robyn N. Conmy

Keyword(s):

Mixed Culture ◽

16S Rrna Gene Sequencing ◽

Gas Chromatography Mass Spectrometry ◽

Rrna Gene ◽

Sequencing Analysis ◽

Dispersed Oil ◽

Degradation Rates ◽

Degrading Bacteria ◽

Rrna Gene Sequencing ◽

Set Up

Abstract 2017-271 In recent years, diluted bitumen (or dilbit) has become an important source of hydrocarbon-based fuel. While information on the degradation of crude oils has been well researched, dilbit degradation has been studied at a much lesser extent. The objective of this study was to compare biodegradation of dilbit with a conventional crude oil (CCO) under various conditions. Two different microcosm experiments were set up, one containing a mixed culture acclimated to dilbit (Kalamazoo River Enrichment, KRC) and the other having a mixed culture enriched on soil contaminated with hydrocarbons (Anderson Ferry Enrichment, AFC). The microcosms were run for 60 d at 25 °C and for 72 days at 5 °C in flasks containing sterile Bushnell Hass broth and naturally dispersed oil. Each flask was inoculated with the KRC and AFC mixed cultures, and rotated on an orbital shaker (200 rpm) at the above stated temperatures. On each sampling day, triplicates were sacrificed to determine the residual hydrocarbon concentration. Additionally, some samples were used to determine the bacterial composition using 16S rRNA gene sequencing analysis. Hydrocarbon analysis (alkanes and PAHs) was performed by gas chromatography/mass spectrometry (GC/MS/MS). Higher degradation rates were achieved at 25 °C as compared to 5 °C. All the enrichments metabolized CCO as well dilbit, but the nature and extent of the degradation was distinct. KRC meso culture was the most effective among all, as it completely removed alkanes and most of the PAHs. AFC enrichment performed differently at the two temperatures; an acclimation period (8 d) was observed at 5 °C while there was no lag at 25 °C. KRC cryo culture as well as AFC culture at both temperatures degraded alkanes completely while they were not able to metabolize heavier fractions of the oil (C2–4 homologues of 3- and 4-ring compounds). All cultures showed the presence of diverse oil degrading bacteria and the differences in their compositions affected the biodegradation. Although dilbit was biodegraded, for all the treatments except AFC at 5 °C, the rate of degradation and the extent of degradation was greater for CCO owing to the higher concentrations of lighter hydrocarbons.

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Microbial population dynamics in laboratory-scale activated sludge reactors

Water Science & Technology ◽

10.2166/wst.2002.0450 ◽

2002 ◽

Vol 46 (1-2) ◽

pp. 19-27 ◽

Cited By ~ 90

Author(s):

K. Kaewpipat ◽

C.P.L. Grady

Keyword(s):

Activated Sludge ◽

Microbial Communities ◽

System Performance ◽

Denaturing Gradient Gel Electrophoresis ◽

Treatment Plant ◽

Laboratory Scale ◽

Rrna Gene ◽

Significant Finding ◽

Prokaryotic Community ◽

Activated Sludge Systems

As a first step in understanding nonlinear dynamics in activated sludge systems, two laboratory-scale sequencing batch reactors were operated under identical conditions and changes in their microbial communities were followed through microscopic examination, macroscopic observation, and denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA gene segments from the prokaryotic community. Two experiments were performed. The first used activated sludge from a local wastewater treatment plant to start the replicate reactors. The second used the biomass from the first experiment as a source by intermixing the two and equally redistributing the biomass into the two replicate reactors. For both experiments, the two reactors behaved fairly similarly and had similar microbial communities for a period of 60 days following start-up. Beyond that, the microbial communities in the two reactors in the first experiment diverged in composition, while those in the second experiment remained fairly similar. This suggests that the degree of change occurring in replicate reactors depends upon the severity of perturbation to which they are exposed. The DGGE data showed that the bacterial communities in both experiments were highly dynamic, even though the system performance of the replicate reactors were very similar, suggesting that dynamics within the prokaryotic community is not necessarily reflected in system performance. Moreover, a significant finding from this study is that replicate activated sludge systems are not identical, although they can be very similar if started appropriately.

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Enhancement of 2,3-Butanediol Production byKlebsiella oxytocaPTCC 1402

Journal of Biomedicine and Biotechnology ◽

10.1155/2011/636170 ◽

2011 ◽

Vol 2011 ◽

pp. 1-7 ◽

Cited By ~ 11

Author(s):

Maesomeh Anvari ◽

Mohammad Reza Safari Motlagh

Keyword(s):

Acetic Acid ◽

Taguchi Method ◽

Submerged Culture ◽

Klebsiella Oxytoca ◽

Culture Conditions ◽

Inoculum Size ◽

Medium Composition ◽

Operating Parameters ◽

Optimal Operating ◽

Mixing Intensity

Optimal operating parameters of 2,3-Butanediol production usingKlebsiella oxytocaunder submerged culture conditions are determined by using Taguchi method. The effect of different factors including medium composition, pH, temperature, mixing intensity, and inoculum size on 2,3-butanediol production was analyzed using the Taguchi method in three levels. Based on these analyses the optimum concentrations of glucose, acetic acid, and succinic acid were found to be 6, 0.5, and 1.0 (% w/v), respectively. Furthermore, optimum values for temperature, inoculum size, pH, and the shaking speed were determined as 37°C, 8 (g/L), 6.1, and 150 rpm, respectively. The optimal combinations of factors obtained from the proposed DOE methodology was further validated by conducting fermentation experiments and the obtained results revealed an enhanced 2,3-Butanediol yield of 44%.

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Biodegradation of Kraft Lignin by a Bacterial Strain Sphingobacterium sp. HY-H

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.548 ◽

2014 ◽

Vol 955-959 ◽

pp. 548-553 ◽

Cited By ~ 1

Author(s):

Jing Duan ◽

Ji Dong Liang ◽

Wen Jing Du ◽

Dong Qi Wang

Keyword(s):

Degradation Products ◽

Treatment Plant ◽

Kinetic Studies ◽

16S Rrna Gene Sequencing ◽

Paper Mill ◽

Kraft Lignin ◽

Rrna Gene ◽

Vanillyl Alcohol ◽

Biochemical Tests ◽

Degrading Bacterium

A lignin-degrading bacterium was isolated on mineral salt medium amended by lignosulfonate (L-MSM) agar from the activated sludge of a pulp and paper mill wastewater treatment plant and identified as Sphingobacterium sp. HY-H by biochemical tests and 16S rRNA gene sequencing. The maximum kraft lignin (KL) degradation capability of strain HY-H was determined to be 28.2% on a COD basis under the optimal conditions of pH 7.0, temperature 30°C, and KL to nitrogen (as NH4Cl) ratio of 2 by mass. Moreover, growth kinetic studies showed the KL tolerance of strain HY-H was relatively high and the analysis of KL degradation products by GC-MS revealed the formation of low-molecular-weight aromatic compounds (LMWACs), such as guaiacol, vanillin and vanillyl alcohol, indicating that the strain HY-H can oxidize guaiacyl (G) units and syringyl (S) units in lignin structure. In addition, some low molecular ketone compounds such as 4-hydroxy-2-butanone and methyl vinyl ketone were detected in the inoculated sample after 48h, further validating the partial but possible degradation of KL by strain HY-H.

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