Coupling Extracts of Plant Coagulants With Solar Disinfection Showed a Complete Inactivation of Faecal Coliforms

2018 ◽  
Vol 47 (1) ◽  
pp. 1700450
Author(s):  
Moa Megersa ◽  
Abebe Beyene ◽  
Argaw Ambelu ◽  
Ludwig Triest
Keyword(s):  
Faecal Coliforms ◽  
Solar Disinfection ◽  
Complete Inactivation

scholarly journals Freshwater production and solar disinfection of water released from the air-conditioning cooling system: an experimental investigation

2020 ◽  
Vol 5 ◽  
pp. 9 ◽  
Author(s):  
Iessa Sabbe Moosa ◽  
Laila Masoud Rashid Al-Iessi ◽  
Hussein A. Kazem
Keyword(s):  
Solar Energy ◽  
Air Conditioning ◽  
Cooling System ◽  
Irradiation Time ◽  
Gas Production ◽  
Hydrogen Gas ◽  
Solar Irradiation ◽  
Solar Disinfection ◽  
Complete Inactivation ◽  
Cooling Air

Providing drinkable water for people is one of the crux duties of any government worldwide. As long, Oman classified among countries that suffer from a shortage of water resources, therefore finding any new sources of water is considered as very substantial work. In present work, a research was carried out on a massive quantity of water that is released out from cooling air-conditioning system in humid zones in Oman as byproduct water. The results showed that the average quantity of water gained from one AC in chosen cities was about 2 L/h, 1.9 L/h, and 1.7 L/h in Muscat, Sohar, and Al-Buraimi respectively. The results exposed that the water was almost distilled water with a pH of about 7. The electrical conductivity was very low, within the range of 45 µS/cm and less. The turbidity of the tested water was low as well, in the range of about 0.6 NTU. Additionally, it was found that solar disinfection technique was very effective to inactivate the existing bacteria in the examined water. A temperature of about 43 °C can be reached after solar irradiation for 2 h with transparent bottles. While, a temperature of around 84 °C was achieved on a sunny day after 6 h of irradiation time. The significant result of the solar disinfection was that the complete inactivation of bacteria could be achieved with an irradiation period of 2–4 h, depending on the number of bacteria per unit volume and the weather state. Moreover, some of the gained water was converted into drinking water after adding some required elements, filtration and disinfection by solar energy. Also, it is strongly recommended to use the released drain-water from cooling air-conditioning systems in the electrolysis unit cells for hydrogen gas production in conjugation with solar energy.

Effect of source water quality on solar disinfection rate under multiple experimental conditions

2014 ◽  
Vol 4 (4) ◽  
pp. 714-719
Author(s):  
M. Mansoor Ahammed ◽  
Shilpa Dave
Keyword(s):  
Natural Waters ◽  
Municipal Wastewater ◽  
Heterotrophic Bacteria ◽  
Exposure Period ◽  
Most Probable Number ◽  
Experimental Conditions ◽  
Probable Number ◽  
Solar Disinfection ◽  
Complete Inactivation ◽  
Naturally Occurring

Water samples from four different sources of varying physico-chemical and microbial quality with their naturally occurring microorganisms were exposed to sunlight in polyethylene terephthalate bottles under similar conditions. Up to 3-log10 reduction of total coliforms (TC) was observed during a 6-h exposure period under weak/moderate radiation conditions (<600 W/m2). Complete inactivation of TC was not achieved in 6 h of exposure for waters with larger initial TC such as river water (1 × 103 most probable number [MPN]/100 mL) and treated municipal wastewater (2 × 105 MPN/100 mL) under these conditions. Heterotrophic bacteria showed lower inactivation rates than did TC. The inactivation rate for spiked Escherichia coli was faster than for naturally occurring coliforms. Further tests with compound parabolic collectors showed that complete inactivation of naturally occurring TC could be achieved within 6 h of exposure for all the natural waters tested. The results of the study thus indicate the need to use naturally occurring organisms in testing the effectiveness of solar disinfection, and the importance of source quality on the inactivation rates of microorganisms.

Solar disinfection for household treatment of roof-harvested rainwater

2008 ◽  
Vol 8 (2) ◽  
pp. 153-160 ◽  
Author(s):  
V. Meera ◽  
M. M. Ahammed
Keyword(s):  
Prolonged Exposure ◽  
Heterotrophic Bacteria ◽  
Inactivation Kinetics ◽  
Bacterial Inactivation ◽  
Solar Disinfection ◽  
Complete Inactivation ◽  
Naturally Occurring ◽  
Significant Difference ◽  
Solar Intensity ◽  
Inactivation Efficiency

The effectiveness of solar disinfection in treating roof-harvested rainwater contaminated with microorganisms was evaluated with a view to its use as a household technology. Coliform and heterotrophic bacteria inactivation kinetics were studied using bottles with different backing surfaces. The effects of various parameters such as turbidity, solar intensity, type of organisms (naturally occurring versus laboratory grown) and bottle volume on bacterial inactivation were studied. Complete inactivation of total coliforms was observed in 6 h when solar radiation exceeded ∼500 W/m2.Under high contamination and overcast conditions, prolonged exposure was needed. Moderate turbidity (38 NTU) did not reduce the inactivation efficiency, but slightly enhanced it. No regrowth of microorganisms was observed after 24 h following solar disinfection. No significant difference in the inactivation kinetics was observed for bottle sizes in the range of 0.5 to 2.0 L. Tests with naturally occurring and laboratory-grown organisms indicated that laboratory-grown organisms were inactivated faster than naturally occurring organisms.

scholarly journals The efficacy of simulated solar disinfection (SODIS) against coxsackievirus, poliovirus and hepatitis A virus

2012 ◽  
Vol 10 (4) ◽  
pp. 531-538 ◽  
Author(s):  
Wayne Heaselgrave ◽  
Simon Kilvington
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Cell Monolayer ◽  
Simulated Sunlight ◽  
Solar Simulator ◽  
Effective Technique ◽  
Solar Disinfection ◽  
Complete Inactivation ◽  
Virus Exposure ◽  
Waterborne Viruses

The antimicrobial activity of simulated solar disinfection (SODIS) against enteric waterborne viruses including coxsackievirus-B5, poliovirus-2 and hepatitis A virus was investigated in this study. Assays were conducted in transparent 12-well polystyrene microtitre plates containing the appropriate viral test suspension. Plates were exposed to simulated sunlight at an optical irradiance of 550 Wm−2 (watts per square metre) delivered from a SUNTEST™ CPS+ solar simulator for 6 hours. Aliquots of the viral test suspensions were taken at set time points and the level of inactivation of the viruses was determined by either culture on a HeLa cell monolayer for coxsackievirus-B5 and poliovirus-2 or by utilising a chromogenic antibody-based approach for hepatitis A virus. With coxsackievirus-B5, poliovirus-2 and hepatitis A virus, exposure to SODIS at an optical irradiance of 550 Wm−2 for 1–2 hours resulted in complete inactivation of each virus. The findings from this study suggest that under appropriate conditions SODIS may be an effective technique for the inactivation of enteric viruses in drinking water. However, further verification studies need to be performed using natural sunlight in the region where the SODIS technology is to be employed to validate our results.

Properties and Biotechnological Application of mutant Derivatives of Mini-intein PRP8 from Penicillium chrysogenum with Improved Control of C-terminal Processing

2019 ◽  
Vol 35 (6) ◽  
pp. 91-101
Author(s):  
F.A. Klebanov ◽  
S.E. Cheperegin ◽  
D.G. Kozlov
Keyword(s):  
Penicillium Chrysogenum ◽  
Protein Denaturation ◽  
Biologically Active ◽  
Cultivation Temperature ◽  
Target Proteins ◽  
E Coli ◽  
Complete Inactivation ◽  
Target Molecules ◽  
Proteins And Peptides

Mutant variants of mini-intein PRP8 from Penicillium chrysogenum (Int4b) with improved control of C-terminal processing were characterized. The presented variants can serve as a basis for self-removed polypeptide tags capable of carrying an affine label and allowing to optimize the process of obtaining target proteins and peptides in E. coli cells. They allow to synthesize target molecules in the composition of soluble and insoluble hybrid proteins (fusions), provide their afnne purification, autocatalytic processing and obtaining mature target products. The presented variants have a number of features in comparison with the known prototypes. In particular the mutant mini-intein Int4bPRO, containing the L93P mutation, has temperature-dependent properties. At cultivation temperature below 30 °C it allows the production of target molecules as part of soluble fusions, but after increasing of cultivation temperature to 37 °C it directs the most of synthesized fusions into insoluble intracellular aggregates. The transition of Int4bPRO into insoluble form is accompanied by complete inactivation of C-terminal processing. Further application of standard protein denaturation-renaturation procedures enable efficiently reactivate Int4bPRO and to carry out processing of its fusions in vitro. Two other variants, Int4b56 and Int4b36, containing a point mutation T62N or combination of mutations D144N and L146T respectively, have a reduced rate of C-terminal processing. Their use in E. coli cells allows to optimize the biosynthesis of biologically active target proteins and peptides in the composition of soluble fusions, suitable for afnne purification and subsequent intein-dependent processing without the use of protein denaturation-renaturation procedures. intein, fusion, processing, processing rate, gelonin The work was supported within the framework of the State Assignment no. 595-00003-19 PR.

Applying Bacteriological Parameters for Evaluating Underground Water Quality

1988 ◽  
Vol 20 (11-12) ◽  
pp. 425-428 ◽  
Author(s):  
H. T. El-Zanfaly ◽  
A. M. Shabaan
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Samples ◽  
Anaerobic Bacteria ◽  
Underground Water ◽  
Faecal Coliforms ◽  
Bacterial Pollution ◽  
Important Approach ◽  
Positive Results ◽  
Faecal Streptococci

A total of 111 water samples were drawn from 15 wells. These samples were subjected to bacteriological examinations to determine the suitability of the monitored wells as source for drinking water. Significant levels of bacterial pollution indicators were detected in the underground water samples during the period of study. Total bacterial counts ranged between 10-104CFU/ml. Faecal streptococci was the most common and detected in 9 6% of water samples. Lower percentages of samples (92, 55 and 45%) were contaminated with total coliforms, faecal coliforms and total clostridia, respectively. Faecal coliforms: faecal streptococci was less than 0.7 in 86% of the examined samples. Anaerobic bacteria were detected in the examined well water samples. Only 101 water samples were tested for anaerobic spore-formers and all showed positive results. Most examined wells do not meet the water quality standards for drinking water. Accordingly, the necessity of controllin bacterial pollution in ground-water through disinfection was clearly confirmed. Testing the underground water for more than one indicator represents an important approach for water quality assurance.

Comparison and Evaluation of Different Microbiological Quality Criteria for Shellfish and Shellfish-Growing Waters

1993 ◽  
Vol 27 (3-4) ◽  
pp. 31-34 ◽  
Author(s):  
E. Martinez-Manzanares ◽  
M. A. Moriñigo ◽  
D. Castro ◽  
M. C. Balebona ◽  
J. J. Borrego
Keyword(s):  
Sea Water ◽  
Microbiological Quality ◽  
Quality Criteria ◽  
Human Consumption ◽  
Faecal Coliforms ◽  
Mediterranean Countries ◽  
Four Seasons ◽  
Microbiological Criteria ◽  
Chamelea Gallina ◽  
Log Normal

The objective of this study is to compare different microbiological criteria based on the control of shellfish-growing waters and shellfish flesh, to assess the microbiological quality of the shellfish harvested in a marine zone affected by discharges of a moderately polluted river. Two species of shellfish grown in Mediterranean countries, cockles (Cardium edule) and striped venus (Chamelea gallina) were chosen to carry out this study. A total of 55 samples of diellfish and sea water were collected over the four seasons of the year. According to the results obtained, the US, EEC and Spanish criteria, based on the level of faecal coliforms in shellfish flesh, guaranteed appropriately their safety for human consumption, but among the criteria based on the level of Escherichia coli, only the Australian criterion has been shown to be totally safe, this microorganism being the best indicator of the presence of Vibrio parahaemolyticus and Salmonella. For the criteria based on the analysis of indicators in seawater, the indicators which relate to the age of faecal pollution, such as spores of clostridium sulfite reducer and faecal streptococci are the best indexes of the presence of pathogens in shellfish. Furthermore, criteria that establish the percentage of water samples that fulfill the microbiological level specified, or log-normal distributions of indicators such as total coliforms, faecal coliforms and E. coli, are better than mean counts.

Comparison of F-specific bacteriophage, enterococci, and faecal coliform densities through a wastewater treatment process employing oxidation ponds

1995 ◽  
Vol 31 (5-6) ◽  
pp. 85-89 ◽  
Author(s):  
S. J. Turner ◽  
G. D. Lewis
Keyword(s):  
Wastewater Treatment ◽  
Treatment Process ◽  
Faecal Coliform ◽  
Indicator Organisms ◽  
Faecal Coliforms ◽  
Wastewater Treatment Process ◽  
Oxidation Pond ◽  
Oxidation Ponds ◽  
Specific Bacteriophage

Over a 12 month period F-specific bacteriophages, faecal coliforms and enterococci were compared as microbial indicator organisms for the quality of a wastewater treatment (oxidation pond) system. Results suggest that enterococci may be the most useful indicator for oxidation pond systems.

An Improved Membrane Filtration Method for Enumeration of Faecal Coliforms and E. Coli by a Fluorogenic β-Glucuronidase Assay

1993 ◽  
Vol 27 (3-4) ◽  
pp. 267-270 ◽  
Author(s):  
M. T. Augoustinos ◽  
N. A. Grabow ◽  
B. Genthe ◽  
R. Kfir
Keyword(s):  
Escherichia Coli ◽  
Water Samples ◽  
Membrane Filtration ◽  
Faecal Coliforms ◽  
Environmental Waters ◽  
Filtration Method ◽  
E Coli ◽  
Wide Range ◽  
Pure Cultures ◽  
Glucuronidase Assay

A fluorogenic β-glucuronidase assay comprising membrane filtration followed by selective enumeration on m-FC agar at 44.5°C and further confirmation using tlie 4-metliylumbelliferyl-β-D-glucuronide (MUG) containing medium was evaluated for the detection of Escherichia coli in water. A total of 200 typical blue and non-typical blue colonies were isolated from sea and fresh water samples using initial selective enumeration on m-FC agar. Pure cultures of the selected colonies were further tested using the MUG assay and identified using the API 20E method. Of the colonies tested which were shown to be positive using the MUG assay 99.4% were Escherichia coli. The results of this study indicate the combination of the m-FC method followed by the MUG assay to be highly efficient for the selection and confirmation of E. coli from a wide range of environmental waters.

Rotavirus removal in experimental waste stabilization pond systems with different geometries and configurations

1995 ◽  
Vol 31 (12) ◽  
pp. 285-290 ◽  
Author(s):  
J. I. Oragui ◽  
H. Arridge ◽  
D. D. Mara ◽  
H. W. Pearson ◽  
S. A. Silva
Keyword(s):  
Clostridium Perfringens ◽  
Slow Process ◽  
Faecal Coliforms ◽  
Waste Stabilization Ponds ◽  
Stabilization Pond ◽  
Waste Stabilization Pond ◽  
Stabilization Ponds ◽  
Waste Stabilization

Rotavirus removal in waste stabilization ponds is a relatively slow process: in a series of ten ponds (a 1-d anaerobic pond followed by nine 2-d ponds) its numbers were reduced from 1.4 × 105 per litre to zero, and in an “innovative” series (a 1-day anaerobic pond, 3-d facultative pond, 3.8-d, 3-d and 5-d maturation ponds) from 5.1 × 104 per litre to <5 per litre. Faecal coliforms were better indicators of rotaviruses than was Clostridium perfringens .

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