Reactor performance and pathogen removal during wastewater treatment by vermifiltration

2016 ◽  
Vol 6 (1) ◽  
pp. 65-73 ◽  
Author(s):  
Sudipti Arora ◽  
A. A. Kazmi
Keyword(s):  
Pathogenic Bacteria ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Inhibitory Effect ◽  
Fecal Coliforms ◽  
Soluble Form ◽  
Reactor Performance ◽  
Pathogen Removal ◽  
Antimicrobial Substances

The application of vermifiltration could reduce the load of chemical and biological pollutants present in wastewater, reducing the pressure over water requirements and allowing the reclamation of the treated water. In the present study, vermifiltration has shown a great potential for chemical pollutants and pathogen removal in wastewater through the synergistic interactions of earthworms and microorganisms. The results of a pilot-scale study showed a higher percentage removal of biochemical oxygen demand (88%), chemical oxygen demand (78%), total suspended solids (83%) and log removal of fecal coliforms (2.61), fecal streptococci (2.50), Salmonella (2.20) and Escherichia coli (2.48) to the levels considered acceptable for reuse in irrigation purposes. Specifically, earthworms in the vermifilter were able to transform insoluble organic material to soluble form followed by selective digestion of the material to finer size, and further degradation by the microorganisms in the reactor. In vitro antimicrobial assay tests also showed that the present microflora had strong inhibitory efficiency against Staphylococcus aureus, E. coli, Pseudomonas aeruginosa and Klebsiella aerogenes. The observed inhibitory effect was found to be responsible for the phenomenon mentioned above, with release of antimicrobial substances by earthworms and associated microflora that showed antimicrobial potency against pathogenic bacteria. The kinetics evaluation showed the predominance of a first order removal model during vermifiltration.

Preliminary in Vitro Investigations on The Inhibitory Activity of The Original Dietary Supplement Oxidal® on Pathogenic Bacterial Strains

2020 ◽  
Vol 11 ◽  
pp. 37-43
Author(s):  
Prof. Teodora P. Popova ◽  
Toshka Petrova ◽  
Ignat Ignatov ◽  
Stoil Karadzhov
Keyword(s):  
Dietary Supplement ◽  
Broad Spectrum ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Clinical Effectiveness ◽  
Inhibitory Effect ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Microbial Strains

The antimicrobial action of the dietary supplement Oxidal® was tested using the classic Bauer and Kirby agar-gel diffusion method. Clinical and reference strains of Staphylococcus aureus and Escherichia coli were used in the studies. The tested dietary supplement showed a well-pronounced inhibitory effect against the microbial strains commensurable with that of the broad-spectrum chemotherapeutic agent Enrofloxacin and showed even higher activity than the broad spectrum antibiotic Thiamphenicol. The proven inhibitory effect of the tested dietary supplement against the examined pathogenic bacteria is in accordance with the established clinical effectiveness standards for antimicrobial agents.

scholarly journals DEVELOPMENT OF IN VITRO METHODOLOGIES FOR INHIBITION OF PATHOGENIC BACTERIA BY POTENTIAL PROBIOTIC LACTOBACILLUS SPS; AN EVIDENCE FOR PRODUCTION OF ANTIMICROBIAL SUBSTANCES

2016 ◽  
Vol 8 (12) ◽  
pp. 277
Author(s):  
Prabhurajeshwar C. ◽  
Kelmani Chandrakanth R.
Keyword(s):  
Bile Salts ◽  
Pathogenic Bacteria ◽  
Antimicrobial Activities ◽  
Local Market ◽  
Preliminary Screening ◽  
Milk Products ◽  
Antimicrobial Substances ◽  
Live Bacteria ◽  
Digestive Health

<p><strong>Objective: </strong>Probiotic products consist of specific strains of live bacteria that have potentially favorable health effects. A number of studies provide evidence that milk products with probiotics may be beneficial for digestive health and may improve various digestive problems. The purpose of the present study was to investigate <em>Lactobacillus</em> species with potential activities isolated from different cheese samples of local market.</p><p><strong>Methods: </strong>A total 42 lactic acid bacteria strains were isolated, fourteen (14/42) best <em>Lactobacillus</em> isolates were selected by preliminary screening as potential probiotics with antimicrobial activity against pathogenic bacteria. All the fourteen <em>Lactobacillus</em> isolates were then characterized <em>in vitro</em> for their probiotic features and antimicrobial activities against pathogens.</p><p><strong>Results: </strong>The results noticed that all selected <em>Lactobacillus</em> isolates (CH3, CH4 and CH6) were screened and confirmed as <em>Lactobacillus. </em>The isolates were able to grow at different pH, NaCl and bile salts, also exhibited the best antimicrobial activities against pathogens. All the isolates were susceptible to antibiotics used and isolates were also revealed the noticeable aggregation and hydrophobicity studies.<strong></strong></p><p><strong>Conclusion: </strong>Selected <em>Lactobacillus </em>isolates were considered as ideal, effective probiotic bacteria. Thus, they could be examined further and contribute to preventing and controlling several infections associated with intestine and for human health benefits.</p>

scholarly journals CONSTITUENTS AND INHIBITORY EFFECT ON HUMAN PATHOGENIC BACTERIA OF THE ROOTS OF SCUTELLARIA BAICALENSIS

2019 ◽  
Vol 57 (1) ◽  
pp. 7
Author(s):  
Duc Long Le ◽  
Huu Tung Nguyen ◽  
Thi Thom Nguyen ◽  
Gyung Ja Choi ◽  
Dinh Hoang Vu ◽  
...  
Keyword(s):  
Ethyl Acetate ◽  
Pathogenic Bacteria ◽  
Inhibitory Effect ◽  
Scutellaria Baicalensis ◽  
Plant Materials ◽  
Chemical Structures ◽  
Human Pathogenic Bacteria ◽  
Antibiotic Effect ◽  
Study Results

Abstract-HCTN_16Methanol extract of the roots of Scutellaria baicalensis effectively inhibited the bacterial growth of human pathogenic bacteria Staphylococcus aureus ATCC 6538, Bacillus cereus ATCC 21768 and Bacillus subtilis ATCC 6633 at MICs of 2,000 µg/mL. n-Hexane, ethyl acetate and aqueous residues were prepared by successively partitioning the methanol extract with n-hexane and ethyl acetate. Among them, only ethyl acetate layer showed antibiotic effect; whereas n-hexane and aqueous layers were inactive against tested bacteria. The ethyl acetate residue was fractionated by silica gel column chromatography to afford three flavonoids and an oligosaccharide. Their chemical structures were elucidated as wogonin (SB1), baicalein (SB4), baicalin (SB5) and tetrasaccharide (SB10) on the basis of the analysis of NMR and MS spectroscopic data. The isolates were evaluated for in vitro inhibitory effect against human pathogenic bacteria using micro dilution bioassay method. Baicalein (SB4) showed a broad-spectrum inhibition against various human pathogenic bacteria. In particular, it was found to potently inhibit S. aureus ATCC 6538 and B. cereus ATCC 21768 with MICs of 9.5 and 38 µg/mL, respectively. The study results demonstrated antibiotic effect of the extracts from the roots of S. baicalensis and characterization of compounds isolated from the plant materials.

Environmental performance of an integrated fixed-film activated sludge (IFAS) reactor treating actual municipal wastewater during start-up phase

2015 ◽  
Vol 72 (10) ◽  
pp. 1840-1850 ◽  
Author(s):  
Nitin Kumar Singh ◽  
Absar Ahmad Kazmi ◽  
Markus Starkl
Keyword(s):  
Activated Sludge ◽  
Pathogenic Bacteria ◽  
Municipal Wastewater ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Lessons Learned ◽  
Present System ◽  
Salmonella Spp ◽  
Start Up ◽  
Fixed Film

The present study summarizes the start-up performance and lessons learned during the start-up and optimization of a pilot-scale plant employing integrated fixed film activated sludge (IFAS) process treating actual municipal wastewater. A comprehensive start-up was tailored and implemented to cater for all the challenges and problems associated with start-up. After attaining desired suspended biomass (2,000–3,000 mg/L) and sludge age (∼7 days), the average biological oxygen demand (BOD) and chemical oxygen demand (COD) removals were observed as 77.3 and 70.9%, respectively, at optimized conditions, i.e. hydraulic retention time (HRT), 6.9 h; return sludge rate, 160%. The influent concentrations of COD, BOD, total suspended solids, NH3-N, total nitrogen and total phosphorus were found to be in the range of 157–476 mg/L, 115–283 mg/L, 152–428 mg/L, 23.2–49.3 mg/L, 30.1–52 mg/L and 3.6–7.8 mg/L, respectively, and the minimum effluent concentrations were achieved as ∼49 mg/L, 23 mg/L, 35 mg/L, 2.2 mg/L, 3.4 mg/L and 2.8 mg/L, respectively, at optimum state. The present system was found effective in the removal of pathogenic bacteria (Escherichia coli, 79%; Salmonella spp., 97.5%; Shigella spp., 92.9%) as well as coliforms (total coliforms, 97.65%; faecal coliforms, 80.35%) without any disinfection unit. Moreover it was observed that the time required for the stabilization of the plant was approximately 3 weeks if other parameters (sludge age, HRT and dissolved oxygen) are set to optimized values.

scholarly journals Brewing and Probiotic Potential Activity of Wild Yeasts Hanseniaspora Uvarum PIT001, Pichia Kluyveri LAR001 and Candida Intermedia ORQ001

2021 ◽  
Author(s):  
Renan Eugênio Araujo Piraine ◽  
Gustavo M Retzlaf ◽  
Vitória S. Gonçalves ◽  
Rodrigo C Cunha ◽  
Fabio Pereira Leivas Leite
Keyword(s):  
Pathogenic Bacteria ◽  
Inhibitory Effect ◽  
Starter Cultures ◽  
Mixed Fermentation ◽  
Candida Intermedia ◽  
Probiotic Potential ◽  
Hanseniaspora Uvarum ◽  
Wide Range ◽  
Pichia Kluyveri

Abstract Non-conventional yeasts can be isolated from a wide range of environmental sources, often found in beverage industry in mixed fermentations, in which the microorganisms’ inoculum usually is not fully known. It is important to know starter cultures, since in addition to favoring reproducibility, other properties can be discovered. Thus, the objective of this work was to identify and characterize yeasts isolated from environment, evaluating their probiotic potential and possible use in brewery. Isolates were obtained from flowers, fruits, leaves and mixed-fermentation beers, being identified by PCR. Yeasts with promising activity were evaluated regarding their growth under different pHs, temperature and presence of organic acids. To explore probiotic potential, in vitro tests were performed of antimicrobial activity and co-aggregation with food pathogens, auto-aggregation, and survival in simulated gastrointestinal tract conditions. In our study, Pichia kluyveri (LAR001), Hanseniaspora uvarum (PIT001) and Candida intermedia (ORQ001) were selected among 20 isolates. P. kluyveri was the only one that tolerated pH 2.5. Lactic acid was not inhibitory, while acetic acid and incubation at 37 °C had a partially inhibitory effect on yeasts growth. All yeasts tolerated α-acids from hops and NaCl up to 1%. It is suggested that isolates are able to adhere to intestinal cells and influence positively the organism in combating pathogens, as they showed auto-aggregation rates above 99% and antagonistic activity to pathogenic bacteria. The yeasts tolerated gastric environment conditions, however were more sensitive to pancreatic conditions. We conclude that isolated non-conventional yeasts showed probiotic potential and promising application in beer fermentation.

scholarly journals The Glycosyltransferase Domain of Penicillin-Binding Protein 2a from Streptococcus pneumoniae Catalyzes the Polymerization of Murein Glycan Chains

2003 ◽  
Vol 185 (15) ◽  
pp. 4418-4423 ◽  
Author(s):  
Anne Marie Di Guilmi ◽  
Andréa Dessen ◽  
Otto Dideberg ◽  
Thierry Vernet
Keyword(s):  
Streptococcus Pneumoniae ◽  
Pathogenic Bacteria ◽  
Catalytic Domain ◽  
Soluble Form ◽  
Lipid Ii ◽  
Extracellular Region ◽  
Catalytically Active ◽  
Bacterial Peptidoglycan

ABSTRACT The bacterial peptidoglycan consists of glycan chains of repeating β-1,4-linked N-acetylglucosaminyl-N-acetylmuramyl units cross-linked through short peptide chains. The polymerization of the glycans, or glycosyltransfer (GT), and transpeptidation (TP) are catalyzed by bifunctional penicillin-binding proteins (PBPs). The β-lactam antibiotics inhibit the TP reaction, but their widespread use led to the development of drug resistance in pathogenic bacteria. In this context, the GT catalytic domain represents a potential target in the antibacterial fight. In this work, the in vitro polymerization of glycan chains by the extracellular region of recombinant Streptococcus pneumoniae PBP2a, namely, PBP2a* (the asterisk indicates the soluble form of the protein) is presented. Dansylated lipid II was used as the substrate, and the kinetic parameters K m and k cat/K m were measured at 40.6 μM (± 15.5) and 1 × 10−3 M−1 s−1, respectively. The GT reaction catalyzed by PBP2a* was inhibited by moenomycin and vancomycin. Furthermore, the sequence between Lys 78 and Ser 156 is required for enzymatic activity, whereas it is dispensable for lipid II binding. In addition, we confirmed that this region of the protein is also involved in membrane interaction, independently of the transmembrane anchor. The characterization of the catalytically active GT domain of S. pneumoniae PBP2a may contribute to the development of new inhibitors, which are urgently needed to renew the antibiotic arsenal.

Antimicrobial peptides isolated from the blood of farm animals

2010 ◽  
Vol 50 (7) ◽  
pp. 660 ◽  
Author(s):  
Pak-Lam Yu ◽  
Danitsja S. van der Linden ◽  
Haryadi Sugiarto ◽  
Rachel C. Anderson
Keyword(s):  
Antimicrobial Peptides ◽  
Pathogenic Bacteria ◽  
Synergistic Effects ◽  
Waste Product ◽  
Pharmaceutical Products ◽  
Farm Animals ◽  
Antimicrobial Substances ◽  
Spectrum Activity ◽  
Conventional Antibiotics

The development of antimicrobial resistance by pathogenic bacteria has fuelled the search for alternatives to conventional antibiotics. Endogenous antimicrobial peptides have the potential to be used as new antimicrobial substances because they have low minimum inhibitory concentration in vitro, have broad-spectrum activity, neutralise lipopolysaccharides, promote wound healing and have synergistic effects with conventional antibiotics. Farm animals, in particular the blood that is a by-product of the meat and poultry industries, are an abundant, and currently underutilised, source of such antimicrobial peptides. These antimicrobial peptides could be isolated and developed into high-value products such as biopreservatives, topical neutraceutical products and pharmaceuticals. There have been some clinical trials of antimicrobial peptides as pharmaceutical products, but up to now, the trials have shown disappointing results. Further research and development is still needed before such peptides can be commercialised and full advantage taken of this waste product of the meat and poultry industries.

Nutrient balancing for enhanced activated sludge reactor performance: UK perspective

2000 ◽  
Vol 41 (12) ◽  
pp. 223-231 ◽  
Author(s):  
J. E. Burgess ◽  
J. Harkness ◽  
P. J. Longhurst ◽  
T. Stephenson
Keyword(s):  
Activated Sludge ◽  
Industrial Wastewater ◽  
Pantothenic Acid ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Toxicity Tests ◽  
Reactor Performance ◽  
Positive Effects ◽  
Activated Sludge Reactor ◽  
Nutrient Balancing

Trace metals (K, Fe, Mg, Cu, Ca, Mn, Al, Zn, Mo, Co) and vitamins (biotin, niacin, pyridoxine, lactoflavin, thiamine, pantothenic acid) were tested for enhancing chemical oxygen demand (COD) and toxicity removal in activated sludge treating trade effluent. Rapid respirometry screening indicated that micronutrient addition could not ameliorate macronutrient deficiencies, but could significantly improve the degradation of hard COD in the wastewater (up to 4.24 kg COD/kg MLSS/d, i.e. 320% of the control) with no significant effect on the air requirement of the sludge. Several positive effects led to the conclusion that micronutrients have the potential to optimise the process performance of activated sludge plants treating industrial wastewater. Porous pots were used to further trial eight of the micronutrients. The retention of biomass in the pots was increased in all cases. Improvements in the degradation of COD (up to 260% of the control) were observed while biological oxygen demand (BOD) degradation was not affected. This implied the use of recalcitrant substrate components as a food source. Toxicity tests showed that the effluents from the experimental porous pots were less toxic than the control effluents. The effects of niacin addition in activated sludge treatment of industrial waste at pilot-scale were: improved sludge handling, increased COD, ammonia, suspended solids and phosphorus removal. Several industrialists saw micronutrient addition as a route to successful adaptation of processes to accommodate toxicity– based legislation.

Pilot study of SBR biological treatment and microfiltration for reclamation and reuse of municipal wastewater

2000 ◽  
Vol 42 (1-2) ◽  
pp. 263-268 ◽  
Author(s):  
R. Messalem ◽  
A. Brenner ◽  
S. Shandalov ◽  
Y. Leroux ◽  
P. Uzlaner ◽  
...  
Keyword(s):  
Water Reuse ◽  
Municipal Wastewater ◽  
Batch Reactor ◽  
Groundwater Resources ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Fecal Coliforms ◽  
Wastewater Reclamation ◽  
Two Stage ◽  
Stage Scheme

In Israel the shortage of water and concern for the quality of groundwater resources have led to an awareness that a national wastewater reclamation program must be developed. Such a program could cover a major part of the agricultural water demand and could facilitate disposal of effluents without health hazards or environmental problems. A two-stage pilot-scale system comprising secondary sequencing batch reactor (SBR) treatment and tertiary microfiltration was operated for the treatment of Beer-Sheva municipal wastewater. The self-cleaning, continuous microfiltration system comprised a filter module made up of hollow fiber microporous membranes, with a pore size distribution of less than 0.1 μm, encapsulated into a bundle. The unit, which has a nominal filtration area of 4 m2, can treat 4–5 m3 of sewage per day, at a nominal rate of about 500 L/h. SBR treatment of the raw sewage produced an effluent with a biochemical oxygen demand (BOD) of &lt;20 mg/L and total suspended solids (TSS) of &lt;20 mg/L. Further treatment by microfiltration resulted in a BOD &lt;5 mg/L, TSS &lt;1 mg/L and turbidity &lt;0.2 nephelometric turbidity units (NTU). Bacterial counts showed 6-log removal of coliforms and fecal coliforms. These results indicate that the two-stage scheme is capable of producing an effluent that meets or even surpasses the requirements for unrestricted water reuse for agriculture.

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