scholarly journals Physiological and biochemical evaluation of pure cultures of problematic filamentous bacteria isolated from activated sludge

2004 ◽  
Author(s):  
◽  
Tshireletso R. Ramothokang
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Pure Culture ◽  
Morphological Traits ◽  
Filamentous Bacteria ◽  
Storage Compounds ◽  
Pure Cultures ◽  
Physiological And Biochemical

Since the development of the activated sludge process, bulking and foaming have been a major problem affecting treatment efficiency. Filamentous bacteria have long been known to be the primary cause of bulking and foaming problems in activated sludge wastewater treatment systems. Attempts to cure filamentous bulking and foaming have thus far not shown great success in effective long-term control measures due to a lack of understanding of these organisms. Chemical methods such as chlorination and the use of hydrogen peroxide are still used to cure bulking but are only effective as interim measures. This could be due to the main factors stimulating filamentous bacterial growth not being changed by these methods for curing bulking and also, a lack of in-depth understanding of filamentous bacteria by scientists. It is therefore important to gain a proper understanding of these bacteria on the basis of their physiological, biochemical and growth characteristics. For all this to be successfully attained, filamentous bacteria need to be studied in pure culture so as to facilitate a better understanding of bulking and foaming and the control thereof during wastewater treatment. The aim of this study was therefore, to isolate and cultivate problematic filamentous bacteria and determine the physiological, biochemical and morphological traits of these organisms in pure culture, with the purpose of being able to integrate these findings to in situ analysis. Using four different isolation techniques, a total of 14 isolates from 7 different wastewater systems were obtained and evaluated for a range of physical, chemical, redox and substrate conditions. Results of the study indicate that filamentous survival and proliferation in BNR systems is largely due to varied phosphate uptake capacities and widespread ability to denitrify both nitrate and nitrite. Lipid hydrolysis is also a major component of filamentous bacterial metabolism with hydrolysis of other large compounds, as revealed by Biolog, such as starch, dextrin, proteins/peptides, Tween 40, Tween 80 and nucleosides indicating an affinity for larger slowly biodegradable substrates. They also strive on a variety of amino acids and sugars. The results obtained in this study revealed that filamentous bacteria are more diverse and complex in their biochemistry and physiology hence the difficulty in achieving long- term optimal control of filamentous bulking in activated sludge. It was concluded that filamentous bacteria have the ability to survive during times of starvation where growth factors are limiting and, this may be attributed to their ability to store storage compounds such as PHB, glycogen and polyP. The filaments' ability to store storage compounds and denitrify, suggests that they may in fact play significant roles in denitrification and EBPR. It is also concluded from this study that the filamentous bacteria under study are sensitive to aromatic compounds and that they have an affinity for slowly biodegradable polymers such as lipids, nucleosides, proteins/ peptides, dextrin and starch. Also concluded is that, the use of Biolog for biochemical profiling! fingerprinting of filamentous bacteria is useful, however, due to the possibility that some organisms may in fact, not grow and! or may give negative results on some and! or all substrates, other strategies. for biochemical profiling be established and used in this regard. Identification and evaluation of filamentous bacteria based on morphological traits is limiting and requires development and optimization of in situ techniques, such as DNAIRNA based probes and micro autoradiography. Bulking and BNR are elaborate and still not fully understood. The filaments' ability to take up phosphates and denitrify means that an advanced understanding of the roles they play in BNR systems and AA- bulking (Anoxic- Aerobic) is still required. Physiological and biochemical fingerprinting of pure cultures of filamentous bacteria is an important basis to understanding these organisms, and establishing potential bulking and foaming criteria for in situ evaluation and verification. It is from a study such as this that the main goal of curing bulking and gaining an enhanced understanding of BNR may be achieved.

Substrate uptake by Gordonia amarae in activated sludge foams by FISH-MAR

2006 ◽  
Vol 54 (1) ◽  
pp. 39-45 ◽  
Author(s):  
E.L. Carr ◽  
K.L. Eales ◽  
R.J. Seviour
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Carbon Sources ◽  
Mycolic Acid ◽  
Substrate Uptake ◽  
Wastewater Treatment Process ◽  
Pure Cultures ◽  
Gordonia Amarae

Gordonia amarae is a right-angled branching filament belonging to the mycolic acid-containing Actinobacteria which is commonly found in many foaming activated sludge wastewater treatment plants. Although studies on different substrates as sole carbon sources by pure cultures of G. amarae have been carried out, none have examined substrate uptake by this organism in situ. Uptake of several hydrophilic and hydrophobic substrates by G. amarae was evaluated in situ using a combination of fluorescence in situ hybridization and microautoradiography. G. amarae could assimilate a range of both hydrophilic and hydrophobic substrates. From the data, G. amarae appears to be physiologically active under aerobic, anaerobic and anoxic condition (NO2 and NO3) for some substrates. This might explain why attempts to control foaming caused by G. amarae using anoxic and anaerobic selectors have been unsuccessful. This study emphasizes that bacteria can behave differently in situ to pure cultures and that it is important to evaluate the in situ physiology of these bacteria if we are to better understand their role in the wastewater treatment process.

Phylogenetic analysis and in situ identification of “Nostocoida limicola”-like filamentous bacteria in activated sludge from industrial wastewater treatment plants

2002 ◽  
Vol 46 (1-2) ◽  
pp. 99-104 ◽  
Author(s):  
J. Snaidr ◽  
C. Beimfohr ◽  
C. Levantesi ◽  
S. Rossetti ◽  
J. van der Waarde ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Industrial Wastewater ◽  
Wastewater Treatment Plants ◽  
Molecular Probes ◽  
Special Focus ◽  
Filamentous Bacteria ◽  
Industrial Wastewater Treatment ◽  
Biological Methods

The diversity of filamentous bacteria present in industrial wastewater treatment plants was analysed by a combination of classical and molecular-biological approaches. Many unknown filamentous bacteria were observed in about 80 screened activated sludge samples from different industries with sometimes severe bulking sludge problems. A special focus was paid to filaments which resembled “Nostocoida limicola”, a filamentous bacterium which was found to be present in many WWTPs. These filamentous bacteria are hardly cultivable and only one strain was obtained and maintained in co-culture with a yeast. The 16S rRNA sequences of several other “Nostocoida limicola”-like filamentous bacteria from different sludge samples were obtained by micromanipulation and different molecular-biological methods. The sequences were phylogenetically analyzed and specific molecular probes were developed and applied. The results clearly demonstrate that “Nostocoida limicola”-like filaments from industrial WWTPs are different from all other “Nostocoida limicola” types investigated so far. Our strains are affiliated to the alpha-subclass of Proteobacteria.

Identity, abundance and physiology of Aquaspirillum-related filamentous bacteria in activated sludge

2006 ◽  
Vol 54 (1) ◽  
pp. 237-245 ◽  
Author(s):  
T.R. Thomsen ◽  
C. Kragelund ◽  
P.H. Nielsen
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Nutrient Removal ◽  
Wastewater Treatment Plants ◽  
Oligonucleotide Probe ◽  
Filamentous Bacteria ◽  
Type B ◽  
Anaerobic Conditions ◽  
Almost All

Microcolony-forming bacteria closely related to the genus Aquaspirillum in the Betaproteobacteria were recently observed to be abundant in many nutrient removal wastewater treatment plants. The developed oligonucleotide probe, Aqs997, however, occasionally also targeted some filamentous bacteria in activated sludge samples when fluorescence in situ hybridization was performed. In this study, the identity, abundance, and ecophysiology of these Aqs997-positive filamentous bacteria were studied in detail. Most of the Aqs997-positive filamentous bacteria could morphologically be identified as either Eikelboom Type 1701, Type 0041/0675 or possibly Type 1851, all characterized by epiphytic growth. They were found in almost all 21 wastewater treatment plants investigated. Two morphotypes were found. Type A filaments, which seemed to be the same genotype as the microcolony-forming bacteria targeted by probe Aqs997.Type B filaments also hybridized with probe GNS941, specific for the Chloroflexi phylum, so the true identity remains unclear. Aqs997-positive filaments usually stained Gram-negative, but Gram-positive filaments were also found, stressing the difficulties in identifying bacteria from morphology and simple staining results. Studies on the ecophysiology by microautoradiography showed that Aqs997-positive filamentous bacteria did not consume acetate and glucose, while some took up butyrate, mannose, and certain amino acids. Most likely, some Aqs997-positive filamentous bacteria were able to perform full denitrification such as the Aqs997-positive microcolony-forming bacteria, and some were able to store polyhydroxyalkanoates under anaerobic conditions, potentially being glycogen accumulating organisms.

Biochemical Patterns Of Two Different H. hydrossis Isolates Identified By FISH

2006 ◽  
Vol 1 (4) ◽  
Author(s):  
TR Ramothokang ◽  
D. Naidoo ◽  
F. Bux
Keyword(s):  
Activated Sludge ◽  
Edible Oils ◽  
Biological Nutrient Removal ◽  
Published Data ◽  
Filamentous Bacteria ◽  
Culture Studies ◽  
Growth Environment ◽  
Physiology And Biochemistry ◽  
Pure Cultures

Filamentous bacteria have been known to be the major cause of activated sludge bulking and foaming. Attempts to overcome bulking and foaming have been implemented but have thus far not proven effective as long term remedial procedures as they fail to take account of the physiology and biochemistry of the causative filamentous bacteria. Published data on the biochemistry and physiology of filamentous bacteria is still very scarce due to the difficulties in obtaining pure cultures. Pure culture studies however, still remain a technology that has shown promise as an essential tool in studying filamentous bacteria on the basis of morphology, nutritional requirements and physiology. The aim of this research was therefore to study isolates of Haliscomenobacter hydrossis (HHY1 and HHY2) on the basis of their biochemistry and physiology. The results obtained demonstrated HHY1 and HHY2 were considerably biochemically diverse. They utilize an array of different substrates for growth, including slowly biodegradable polymers (dextrin, starch, edible oils and casein) and, they also grow optimally at wide ranges of temperature and pH. It was also revealed that they possess denitrifying capabilities and belong to the functional group of sequential denitrifiers. This equips them with a survival and growth advantage in a complex growth environment as that of the activated sludge process. These findings may lead to a better understanding of the biochemical and physiological conditions that may incite bulking and/or foaming and a better understanding of Biological Nutrient Removal systems, areas that are still in need of much attention.

scholarly journals Deep learning-based morphology classification of activated sludge flocs in wastewater treatment plants

2021 ◽  
Author(s):  
Hisashi Satoh ◽  
Yukari Kashimoto ◽  
Naoki Takahashi ◽  
Takashi Tsujimura
Keyword(s):  
Wastewater Treatment ◽  
Deep Learning ◽  
Activated Sludge ◽  
Morphological Change ◽  
Wastewater Treatment Plants ◽  
Filamentous Bacteria ◽  
Sludge Flocs

A deep learning-based two-label classifier 1 recognized a 20% morphological change in the activated flocs. Classifier-2 quantitatively recognized an abundance of filamentous bacteria in activated flocs.

scholarly journals Time-series genome-centric analysis unveils bacterial response to operational disturbance in activated sludge

2019 ◽  
Author(s):  
María Victoria Pérez ◽  
Leandro D. Guerrero ◽  
Esteban Orellana ◽  
Eva L. Figuerola ◽  
Leonardo Erijman
Keyword(s):  
Growth Rate ◽  
Time Series ◽  
Wastewater Treatment ◽  
Activated Sludge ◽  
Microbial Communities ◽  
Wastewater Treatment Plant ◽  
Treatment Plant ◽  
Operating Conditions ◽  
The Face

ABSTRACTUnderstanding ecosystem response to disturbances and identifying the most critical traits for the maintenance of ecosystem functioning are important goals for microbial community ecology. In this study, we used 16S rRNA amplicon sequencing and metagenomics to investigate the assembly of bacterial populations in a full-scale municipal activated sludge wastewater treatment plant over a period of three years, including a period of nine month of disturbance, characterized by short-term plant shutdowns. Following the reconstruction of 173 metagenome-assembled genomes, we assessed the functional potential, the number of rRNA gene operons and thein situgrowth rate of microorganisms present throughout the time series. Operational disturbances caused a significant decrease in bacteria with a single copy of the ribosomal RNA (rrn) operon. Despite only moderate differences in resource availability, replication rates were distributed uniformly throughout time, with no differences between disturbed and stable periods. We suggest that the length of the growth lag phase, rather than the growth rate, as the primary driver of selection under disturbed conditions. Thus, the system could maintain its function in the face of disturbance by recruiting bacteria with the capacity to rapidly resume growth under unsteady operating conditions.IMPORTANCEIn this work we investigated the response of microbial communities to disturbances in a full-scale activated sludge wastewater treatment plant over a time-scale that included periods of stability and disturbance. We performed a genome-wide analysis, which allowed us the direct estimation of specific cellular traits, including the rRNA operon copy number and the in situ growth rate of bacteria. This work builds upon recent efforts to incorporate growth efficiency for the understanding of the physiological and ecological processes shaping microbial communities in nature. We found evidence that would suggest that activated sludge could maintain its function in the face of disturbance by recruiting bacteria with the capacity to rapidly resume growth under unsteady operating conditions. This paper provides relevant insights into wastewater treatment process, and may also reveal a key role for growth traits in the adaptive response of bacteria to unsteady environmental conditions.

In situ detection of cell surface hydrophobicity of probe-defined bacteria in activated sludge

2001 ◽  
Vol 43 (6) ◽  
pp. 97-103 ◽  
Author(s):  
J. L. Nielsen ◽  
L. H. Mikkelsen ◽  
P. H. Nielsen
Keyword(s):  
Activated Sludge ◽  
Surface Properties ◽  
Treatment Plant ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Substrate Uptake ◽  
Filamentous Bacteria ◽  
In Situ Conditions ◽  
Bacterial Surfaces

The surface hydrophobicity of different types of bacteria in activated sludge were investigated under in situ conditions by following the adhesion of fluorescent microspheres with defined surface properties to bacterial surfaces (the MAC-method). This technique was combined with identification of the bacteria with fluorescence in situ hybridization with rRNA-targeted oligonucleotides (FISH) and could thus be used for characterization of surface properties of probe-defined bacteria directly in a complex system without prior enrichment or isolation. This MAC-FISH technique could be used for single bacteria as well as filamentous bacteria. In the investigated activated sludge from an industrial wastewater treatment plant, two types of filamentous bacteria dominated. One morphotype consistently attracted only very few hydrophobic microspheres, indicating that the thin sheath of exopolymers around the cells had a hydrophilic surface. Use of a hierarchical set of gene probes revealed that these filaments were sulphide oxidising Thiothrix spp. The other predominating filamentous morphotype had a thick, very hydrophobic exopolymeric sheath. This filamentous bacterium was found to belong to the alpha-Proteobacteria. The relevance of the significant differences in surface hydrophobicity for the two morphotypes in respect to substrate uptake and floc formation is discussed.

Application of oligonucleotide probes for the detection of Thiothrix spp. in activated sludge plants treating paper and board mill wastes

2002 ◽  
Vol 46 (1-2) ◽  
pp. 559-564 ◽  
Author(s):  
S.B. Kim ◽  
M. Goodfellow ◽  
J. Kelly ◽  
G.S. Saddler ◽  
A.C. Ward
Keyword(s):  
Activated Sludge ◽  
Bacterial Population ◽  
Oligonucleotide Probe ◽  
In Situ Hybridisation ◽  
Filamentous Bacteria ◽  
Phylogenetic Groups ◽  
Investigation Period ◽  
Mixed Populations ◽  
Conventional Microscopy

Filamentous bacteria belonging to the genus Thiothrix were detected in activated sludge samples using the fluorescent in situ hybridisation (FISH) technique. A 16S rRNA-targeted oligonucleotide probe was developed for the detection of members of the T. fructosivorans group, and the performance of probe TNI for the detection of Thiothrix nivea group was enhanced by using an unlabeled competitor. A set of 5 probes covering all phylogenetic groups of Thiothrix were used to examine samples taken from selected activated sludge plants treating paper and board mill wastes. Members of the T. eikelboomii group formed the predominant filamentous bacterial population in plants experiencing poor sludge settleability, whereas members of the T. nivea group were commonly found but not dominantly in the remaining plants. Members of the T. fructosivorans group were not detected at any significant level in any of the samples. The distribution of the main Thiothrix types remained unchanged throughout the investigation period. It was evident that mixed populations of Thiothrix spp. were present in all activated sludge samples investigated, the observed differences were in the relative abundance of the various groups. These findings were supported by the results obtained using conventional microscopy.

Performances of three R-AN-D-N wastewater treatment plants in the Czech Republic

2004 ◽  
Vol 50 (7) ◽  
pp. 249-255 ◽  
Author(s):  
Z. Bejvl ◽  
P. Matuška ◽  
J. Stara ◽  
P. Chudoba
Keyword(s):  
Wastewater Treatment ◽  
Czech Republic ◽  
Activated Sludge ◽  
Nutrient Removal ◽  
Wastewater Treatment Plants ◽  
Industrial Effluents ◽  
Filamentous Bacteria ◽  
The Czech Republic ◽  
Treated Sewage ◽  
Nutrient Removal Efficiency

The evolution of Czech standards requires higher efficiency of nutrient removal from municipal wastewaters. At the beginning of the last decade of 20th century, a new activated sludge configuration called R-AN-D-N process has been described, successfully tested and now largely used at several wastewater treatment plants (WWTP) in the Czech republic. The main feature of the R-AN-D-N process is the introduction of a regeneration zone in sludge recycle, which enables to increase sludge age in the system without any substantial increase in WWTP volume. Performances of three Czech large WWTP with R-AN-D-N configuration have been monitored and compared within a period of one and a half years. The results confirmed excellent nutrient removal efficiency for wastewaters with different proportion between sewage and industrial effluents. Two of three monitored WWTP received wastewaters from breweries (Budweiser and Pilsner Urquell). The settleability of activated sludge from all three WWTP was correct, with SVI values usually ranging from 50 to 150 ml/g. Monitoring of sludge composition indicated proliferation of several filamentous bacteria, particularly types 0581, 0092 and M. parvicella. No severe bulking events were observed. Finally, the operational costs expressed in CZK (Czech crown: 1CZK = €0.0322) per cubic metre of treated sewage or per capita amounts respectively from 2.24 to 6.52, and from 285 to 342.

scholarly journals Phylogenetic Analysis of and Oligonucleotide Probe Development for Eikelboom Type 021N Filamentous Bacteria Isolated from Bulking Activated Sludge

2000 ◽  
Vol 66 (11) ◽  
pp. 5043-5052 ◽  
Author(s):  
Takahiro Kanagawa ◽  
Yoichi Kamagata ◽  
Shinobu Aruga ◽  
Tetsuro Kohno ◽  
Matthias Horn ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Oligonucleotide Probe ◽  
Sequence Similarity ◽  
Rdna Sequence ◽  
Filamentous Bacteria ◽  
16S Rdna Sequence ◽  
Monophyletic Cluster ◽  
16S Ribosomal Dna ◽  
In Situ Detection

ABSTRACT Fifteen filamentous strains, morphologically classified as Eikelboom type 021N bacteria, were isolated from bulking activated sludges. Based on comparative 16S ribosomal DNA (rDNA) sequence analysis, all strains form a monophyletic cluster together with all recognized Thiothrix species (88.3 to 98.7% 16S rDNA sequence similarity) within the gamma-subclass ofProteobacteria. The investigated Eikelboom type 021N isolates were subdivided into three distinct groups (I to III) demonstrating a previously unrecognized genetic diversity hidden behind the uniform morphology of the filaments. For in situ detection of these bacteria, 16S rRNA-targeted oligonucleotide probes specific for the entire Eikelboom type 021N-Thiothrix cluster and the Eikelboom type 021N groups I, II, and III, respectively, were designed, evaluated, and successfully applied in activated sludge.

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