scholarly journals Influence of salinity and organic nutrient concentration on survival and growth of Vibrio cholerae in aquatic microcosms.

1982 ◽  
Vol 43 (5) ◽  
pp. 1080-1085 ◽  
Author(s):  
F L Singleton ◽  
R W Attwell ◽  
M S Jangi ◽  
R R Colwell
Keyword(s):  
Vibrio Cholerae ◽  
Nutrient Concentration ◽  
Aquatic Microcosms ◽  
Organic Nutrient ◽  
Survival And Growth

Survival and Growth of Vibrio cholerae O139 in Selected Malaysian Street Foods

1997 ◽  
Vol 60 (6) ◽  
pp. 644-648 ◽  
Author(s):  
GULAM RUSUL ◽  
CHONG KAM CHUN ◽  
SON RADU
Keyword(s):  
Vibrio Cholerae ◽  
Slow Growth ◽  
Food Poisoning ◽  
Rice Flour ◽  
Soy Sauce ◽  
Brown Sugar ◽  
Vibrio Cholerae O139 ◽  
Survival And Growth ◽  
Incubation Temperatures ◽  
And Storage

The growth of Vibrio cholerae O139 inoculated into cendol (a mixture of coconut milk, brown sugar, and green jelly from rice flour), rojak (prawn paste, sugar, soy sauce, spices, garlic, and peanut gravy), gravy, tofu, fried tofu, and wheat-flour noodles (all except rojak gravy containing the natural microbial flora) was examined at four incubation temperatures (7, 15,25, and 35°C). V. cholerae O139 grew well in cendol incubated at 25 and 35°C but not at 15°C or below. No growth of V. cholerae O139 in rojak gravy was detected at any temperature except for very slow growth at 35°C. V. cholerae O139 inoculated into tofu exhibited slow growth at 25 and 35°C and growth was not detected at 7 and 15°C. However, in fried tofu, the organism entered the growth phase after 12 h of incubation at 25 and 35°C. Growth of V. cholerae O139 was not demonstrated in noodles at any incubation temperatures. Nutrient broth with 1% NaCl added supported the growth of V. cholerae O139 at 25 and 35°C. At both of these incubation temperatures mean generation time was longer at pH 5 than at pH 8. The high variation in growth of V. cholerae O139 in the distinct foods examined might have been due to differences in pH, fat content, and aw. Proper sanitary practices and storage of foods at refrigeration temperatures will help to reduce the possibility of growth by Vibrio cholerae O139 in foods to levels which do not imply a risk for food-poisoning.

scholarly journals Survival and growth of Vibrio cholerae and Escherichia coli in treated groundwater consumed in northern Cameroon

2020 ◽  
Vol 10 (12) ◽  
Author(s):  
Moussa Djaouda ◽  
Zoua Wadoubé ◽  
Odile Baponwa ◽  
Soumayyata Youssoufa ◽  
Bouba Gaké ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Mineral Water ◽  
Tap Water ◽  
Well Water ◽  
Bacterial Strains ◽  
E Coli ◽  
Northern Cameroon ◽  
Oral Pathogens ◽  
Survival And Growth

AbstractTreated groundwater is a major source of drinking water but subject to potential contamination of fecal–oral pathogens. To understand ecology of the pathogens in the treated water, this study evaluated survival and growth of Vibrio cholerae and Escherichia coli in the treated groundwater in northern Cameroon. E. coli and V. cholerae O1 were isolated from human feces. Water samples were collected from the following sources: a well, tap water from the Cameroon Water Utilities Company, and mineral and borehole waters sold in Maroua, respectively. These waters were treated by one or more processes, including autoclaving, filtration, chlorination and ozonation and were used for the constitution of microcosms. E. coli and V. cholerae were inoculated into each microcosm at respective concentrations of 50 CFU/10 mL (separately) and 40 CFU/10 mL each (together). All bacterial strains survived in all microcosms were used. The ability to survive and grow varied with the bacterial strain and microcosm (P < 0.05). When inoculated separately into the same type of microcosms, V. cholerae grew faster than E. coli with the latter even showing decrease in concentration in mineral water. When inoculated together, V. cholerae grew faster than E. coli, except in autoclaved well water and filtered and autoclaved well water. Autochthonous ultramicroflora inhibited the growth of E. coli in filtered well water (P < 0.05).

Survival and Multiplication of Vibrio cholerae Serotype Ogawa in Reconstituted Infant Milk

1990 ◽  
Vol 53 (12) ◽  
pp. 1071-1072 ◽  
Author(s):  
M. O. ODUGBO ◽  
S. I. ONUORAH ◽  
A. A. ADESIYUN
Keyword(s):  
Adverse Effect ◽  
Vibrio Cholerae ◽  
Room Temperature ◽  
Milk Formula ◽  
Competitive Growth ◽  
Ambient Conditions ◽  
Survival And Growth ◽  
Effects Of Temperature ◽  
Ph Range

In vitro studies were conducted to determine the effects of temperature, pH, and competitive growth of other microorganisms on the viability and multiplication of Vibrio cholerae serotype Ogawa in reconstituted infant milk (nonsterile). Following inoculation of milk sample (at a pH range of 6.0 to 6.4), the V. cholerae population detected on thiosulfate-citrate-bile sucrose (TCBS) agar increased from 9.5 × 103 per g to 7.4 × 104, 2.6 × 108, and 1.9 × 109 per g after 12 h at 4°C, 25°C (room temperature) and 37°C, respectively. At a pH of 5.5, an approximate 100-fold rise in V. cholerae was observed after 12 h at 25°C, while within a pH range of 6.5 to 8.5, a five logarithmic increase in numbers was detected. The presence of other microorganisms did not appear to have any adverse effect on V. cholerae survival and growth in milk. The study demonstrates that at ambient conditions V. cholerae contamination of infant milk formula by carriers or infected mothers could lead to multiplication of the organism and hence pose serious health risk to infants.

scholarly journals Survival and Growth of Vibrio cholerae, Escherichia coli, and Salmonella Spp. in Well Water Used for Drinking Purposes in Garoua (North Cameroon)

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Moussa Djaouda ◽  
Bouba Gaké ◽  
Daniel Ebang Menye ◽  
Serge Hubert Zébazé Togouet ◽  
Moïse Nola ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Well Water ◽  
Bacterial Survival ◽  
Bacterial Strains ◽  
Salmonella Spp ◽  
E Coli ◽  
Antimicrobial Substances ◽  
Survival And Growth ◽  
Faecal Bacteria

The ability of strains of faecal bacteria (Vibrio cholerae, Escherichia coli ATCC 25922, and four strains of Salmonella isolated, resp., from well water, pig, poultry, and human urine in Garoua) to survive or grow in well water microcosms was compared. Water samples were obtained from two wells in Garoua (north Cameroun). Autoclaving at 121°C for 15 min and filtration through 0.2 µm filter were used to make microcosms. Microcosms were constituted of unfiltered-autoclaved, filtered-nonautoclaved, and filtered-autoclaved well waters. Bacterial strains were inoculated at initial cell concentration of 3 Log10CFU/mL. All strains were able to survive/grow in used microcosms, and a maximal concentration of 5.61 Log10CFU/mL was observed. Survival abilities were strain and microcosm dependent. The declines were more pronounced in filtered-nonautoclaved water than in the other microcosms. E. coli and Salmonella sp. (poultry strain) lowered to undetectable levels (<1 Log10CFU/mL) after two days of water storage. V. cholera decreased over time, but surviving cells persisted for longer period in filtered-nonautoclaved water from well W1 (1.91 Log10CFU/mL) and well W2 (2.09 Log10CFU/mL). Competition for nutrients and/or thermolabile antimicrobial substances synthesized by “ultramicrocells” or by the autochthonous bacteria retained by the filter might affect the bacterial survival.

scholarly journals Niche adaptation limits bacteriophage predation of Vibrio cholerae in a nutrient-poor aquatic environment

2018 ◽  
Author(s):  
Cecilia A. Silva-Valenzuela ◽  
Andrew Camilli
Keyword(s):  
Vibrio Cholerae ◽  
Direct Evidence ◽  
Biological Entity ◽  
Aquatic Environments ◽  
Natural Setting ◽  
Aquatic Microcosms ◽  
Human Small Intestine ◽  
Niche Adaptation ◽  
Adaptation Limits ◽  
Potential Use

AbstractVibrio cholerae, the causative agent of cholera, has reservoirs in fresh and brackish water where it interacts with virulent bacteriophages. Phages are the most abundant biological entity on earth and co-evolve with bacteria. It was reported that concentrations of phage and V. cholerae inversely correlate in aquatic reservoirs and in the human small intestine, and therefore that phages may quench cholera outbreaks. Although there is strong evidence for phage predation in cholera patients, evidence is lacking for phage predation of V. cholerae in aquatic environments. Here, we used three virulent phages, ICP1, ICP2, and ICP3, commonly shed by cholera patients in Bangladesh, as models to understand the predation dynamics in microcosms simulating aquatic environments. None of the phages were capable of predation in fresh water, and only ICP1 was able to prey on V. cholerae in estuarine water due to a requirement for salt. We conclude that ICP2 and ICP3 are better adapted for predation in a nutrient rich environment. Our results point to the evolution of niche-specific predation by V. cholerae-specific virulent phages, which complicates their use in predicting or monitoring cholera outbreaks as well as their potential use in reducing aquatic reservoirs of V. cholerae in endemic areas.Significance statementVirulent phages can reduce populations of bacteria and help shape bacterial evolution. Here, we used three virulent phages to understand their equilibrium with V. cholerae in nutrient-limiting aquatic microcosms. It has been proposed that phages quench cholera outbreaks, but no direct evidence of phage predation in aquatic environments had been established. Here we show that different phages possess varied abilities to infect in certain niches or stages of the host bacterial life cycle. Unveiling the phage/bacterial interactions in their natural setting is important to the understanding of cholera outbreaks and could be ultimately used to help develop a method for outbreak prediction and/or control.

Physiological aspects of the ecology of Dicranum fuscescens in the subarctic. II. Seasonal patterns of organic nutrient content

1977 ◽  
Vol 55 (16) ◽  
pp. 2168-2177 ◽  
Author(s):  
Peter R. Hicklenton ◽  
Walter C. Oechel
Keyword(s):  
Nutrient Concentration ◽  
Dry Weight ◽  
Nutrient Content ◽  
Seasonal Patterns ◽  
Biomass Distribution ◽  
Seasonal Trends ◽  
Organic Nutrient ◽  
Total Carbohydrates ◽  
Lichen Woodland

Individual plants of Dicranum fuscescens were collected from two field sites (a highland semitundra and a lowland lichen woodland) near Schefferville, Quebec (latitude 55° N), for 4½ months during 1974. Collections were made at 2-week intervals from June until the 2nd week in October. Samples were separated into green and brown shoot components and oven-dried. Subsequently analyses were carried out to determine concentrations of total carbohydrates (sugar and starch) and lipids in the respective tissues. Total carbohydrates were found to increase in the green tissues towards the end of the season reaching a maximum of between 10 and 10.5% ash-free tissue dry weight in October. Lipid concentrations showed a maximum of between 3.6 and 4.0% ash-free dry weight during July and subsequently declined, in the same tissues. Seasonal trends of nutrient concentration in the brown portions of the shoot were not marked.An investigation of biomass distribution in complete plants of D. fuscescens revealed that brown shoots accounted for more than half of the total. Mean lengths of these parts of the shoot were about twice those of the upper stem.

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