scholarly journals Comparison of biofilm formation and water quality when water from different sources was stored in large commercial water storage tanks

2012 ◽  
Vol 11 (1) ◽  
pp. 30-40 ◽  
Author(s):  
Venessa van der Merwe ◽  
Stacey Duvenage ◽  
Lise Korsten
Keyword(s):  
Water Quality ◽  
Potable Water ◽  
Water Storage ◽  
Water Source ◽  
Sampling Point ◽  
Storage Tanks ◽  
Long Term Storage ◽  
Biofilm Development ◽  
Term Storage

Rain-, ground- and municipal potable water were stored in low density polyethylene storage tanks for a period of 90 days to determine the effects of long-term storage on the deterioration in the microbial quality of the water. Total viable bacteria present in the stored water and the resultant biofilms were enumerated using heterotrophic plate counts. Polymerase chain reaction (PCR) and Colilert-18® tests were performed to determine if the faecal indicator bacteria Escherichia coli was present in the water and in the biofilm samples collected throughout the study. The municipal potable water at the start of the study was the only water source that conformed to the South African Water Quality Guidelines for Domestic Use. After 15 days of storage, this water source had deteriorated microbiologically to levels considered unfit for human consumption. E. coli was detected in the ground- and potable water and ground- and potable biofilms periodically, whereas it was detected in the rainwater and associated biofilms at every sampling point. Imperfections in the UV resistant inner lining of the tanks were shown to be ecological niches for microbial colonisation and biofilm development. The results from the current study confirmed that long-term storage can influence water quality and increase the number of microbial cells associated with biofilms on the interior surfaces of water storage tanks.

An Experimental Approach to the Function of Classic Maya Chultuns

1971 ◽  
Vol 36 (3) ◽  
pp. 322-335 ◽  
Author(s):  
Dennis E. Puleston
Keyword(s):  
Experimental Approach ◽  
Experimental Studies ◽  
Water Storage ◽  
Food Storage ◽  
Food Crop ◽  
Traditional Foods ◽  
Long Term Storage ◽  
Brosimum Alicastrum ◽  
Term Storage

AbstractExperimental techniques have provided an exciting breakthrough for the functional analysis of Maya chultuns. While deep cistern-like chultuns, common at certain sites in the northern lowlands, have been shown to be functional for water storage, smaller lateral-chambered chultuns characteristic of certain parts of the southern lowlands probably had a very different function. Excavation and examination of the latter features, in light of a whole range of possibilities, suggest that they were constructed to be used for food storage. Experimental studies, however, reveal them to be unsuitable for the storage of most traditional foods, including maize. At least one local food crop, the seed of the ramon (Brosimum alicastrum, Moraceae), appears to be ideally suited for long-term storage under these conditions. Chambers constructed beneath platforms in the northern lowlands may have been used for the storage of maize. A need for more experimental work is indicated.

scholarly journals Microbial occurrence in liquid nitrogen storage tanks: a challenge for cryobanking?

2021 ◽  
Author(s):  
Felizitas Bajerski ◽  
Manuela Nagel ◽  
Joerg Overmann
Keyword(s):  
Risk Assessment ◽  
Quality Management ◽  
Liquid Nitrogen ◽  
Potential Risk ◽  
Biological Materials ◽  
Cross Contamination ◽  
Storage Tanks ◽  
Long Term Storage ◽  
Term Storage

Abstract Modern biobanks maintain valuable living materials for medical diagnostics, reproduction medicine, and conservation purposes. To guarantee high quality during long-term storage and to avoid metabolic activities, cryostorage is often conducted in the N2 vapour phase or in liquid nitrogen (LN) at temperatures below − 150 °C. One potential risk of cryostorage is microbial cross contamination in the LN storage tanks. The current review summarises data on the occurrence of microorganisms that may compromise the safety and quality of biological materials during long-term storage. We assess the potential for the microbial contamination of LN in storage tanks holding different biological materials based on the detection by culture-based and molecular approaches. The samples themselves, the LN, the human microbiome, and the surrounding environment are possible routes of contamination and can cause cross contaminations via the LN phase. In general, the results showed that LN is typically not the source of major contaminations and only a few studies provided evidence for a risk of microbial cross contamination. So far, culture-based and culture-independent techniques detected only low amounts of microbial cells, indicating that cross contamination may occur at a very low frequency. To further minimise the potential risk of microbial cross contaminations, we recommend reducing the formation of ice crystals in cryotanks that can entrap environmental microorganisms and using sealed or second sample packing. A short survey demonstrated the awareness for microbial contaminations of storage containers among different culture collections. Although most participants consider the risk of cross contaminations in LN storage tanks as low, they prevent potential contaminations by using sealed devices and − 150 °C freezers. It is concluded that the overall risk for cross contaminations in biobanks is relatively low when following standard operating procedures (SOPs). We evaluated the potential sources in detail and summarised our results in a risk assessment spreadsheet which can be used for the quality management of biobanks. Key points • Identification of potential contaminants and their sources in LN storage tanks. • Recommendations to reduce this risk of LN storage tank contamination. • Development of a risk assessment spreadsheet to support quality management.

Development of a Separate Tank with an Electrolysis-Dependent Bacteria Controlling System for the Long Term Storage of Potable Water

2006 ◽  
Vol 11 (4) ◽  
pp. 175-181 ◽  
Author(s):  
AKINORI ISHIZUKA ◽  
MASATAKA TANJI ◽  
NOBUATSU HAYASHI ◽  
AKIHIRO WAKABAYASHI ◽  
HIDEKI TATSUMOTO ◽  
...  
Keyword(s):  
Potable Water ◽  
Long Term Storage ◽  
Controlling System ◽  
Term Storage

Survival of wood-inhabiting fungi stored for 10 years in water and under oil

1992 ◽  
Vol 38 (8) ◽  
pp. 861-864 ◽  
Author(s):  
Gary C. Johnson ◽  
Andrew K. Martin
Keyword(s):  
Key Words ◽  
Water Storage ◽  
Mineral Oil ◽  
Sterile Water ◽  
Long Term Storage ◽  
Oil Storage ◽  
Term Storage ◽  
Water Survival

Subcultures of 1064 isolates of 393 species of wood-inhabiting fungi were stored both under sterile mineral oil and in sterile water for 10 years. A high proportion (98%) of the Basidiomycotina isolates survived storage under oil, whereas only 26% survived in sterile water. Survival of most isolates of Ascomycotina (91% under oil, 72% in water) and Deuteromycotina (96% under oil, 92% in water) was somewhat less in water than under oil. Key words: fungal storage, long-term storage, oil storage, water storage, Basidiomycotina.

Modelling of Moisture Movement in Wood during Outdoor Storage

2001 ◽  
Vol 6 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
F. Ivanauskas ◽  
I. Juodeikienė ◽  
A. Kajalavičius
Keyword(s):  
Experimental Data ◽  
Finite Difference ◽  
Climatic Conditions ◽  
Two Dimensional ◽  
Moisture Movement ◽  
Finite Difference Technique ◽  
Long Term Storage ◽  
Space Formulation ◽  
Term Storage

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.

Trehalose: a cryoprotectant that enhances recovery and preserves function of human pancreatic islets after long-term storage

Diabetes ◽  
1997 ◽  
Vol 46 (3) ◽  
pp. 519-523 ◽  
Author(s):  
G. M. Beattie ◽  
J. H. Crowe ◽  
A. D. Lopez ◽  
V. Cirulli ◽  
C. Ricordi ◽  
...  
Keyword(s):  
Pancreatic Islets ◽  
Human Pancreatic Islets ◽  
Long Term Storage ◽  
Term Storage
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