PHAGOCYTOSIS OF PATHOGENIC MICROBES ON SOLID CULTURE MEDIA BY AN AMEBA

2009 ◽  
Vol 25 (3) ◽  
pp. 360-362
Author(s):  
Kristian Ødegaard
Keyword(s):  
Culture Media ◽  
Solid Culture ◽  
Pathogenic Microbes

scholarly journals Characterization of Drug-Resistant Lipid-Dependent Differentially Detectable Mycobacterium tuberculosis

2021 ◽  
Vol 10 (15) ◽  
pp. 3249
Author(s):  
Annelies W. Mesman ◽  
Seung-Hun Baek ◽  
Chuan-Chin Huang ◽  
Young-Mi Kim ◽  
Sang-Nae Cho ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Culture Media ◽  
Multidrug Resistant ◽  
Culture Conditions ◽  
Sputum Smear ◽  
Smear Microscopy ◽  
Solid Culture ◽  
Lowenstein Jensen ◽  
Genetic Mechanisms ◽  
Lipid Resuscitation

An estimated 15–20% of patients who are treated for pulmonary tuberculosis (TB) are culture-negative at the time of diagnosis. Recent work has focused on the existence of differentially detectable Mycobacterium tuberculosis (Mtb) bacilli that do not grow under routine solid culture conditions without the addition of supplementary stimuli. We identified a cohort of TB patients in Lima, Peru, in whom acid-fast bacilli could be detected by sputum smear microscopy, but from whom Mtb could not be grown in standard solid culture media. When we attempted to re-grow Mtb from the frozen sputum samples of these patients, we found that 10 out of 15 could be grown in a glycerol-poor/lipid-rich medium. These fell into the following two groups: a subset that could be regrown in glycerol after “lipid-resuscitation”, and a group that displayed a heritable glycerol-sensitive phenotype that were unable to grow in the presence of this carbon source. Notably, all of the glycerol-sensitive strains were found to be multidrug resistant. Although whole-genome sequencing of the lipid-resuscitated strains identified 20 unique mutations compared to closely related strains, no single genetic lesion could be associated with this phenotype. In summary, we found that lipid-based media effectively fostered the growth of Mtb from a series of sputum smear-positive samples that were not culturable in glycerol-based Lowenstein–Jensen or 7H9 media, which is consistent with Mtb’s known preference for non-glycolytic sources during infection. Analysis of the recovered strains demonstrated that both genetic and non-genetic mechanisms contribute to the observed differential capturability, and suggested that this phenotype may be associated with drug resistance.

Manufacturing of Solid Culture Media in film Bags for Shiitake Cultivation

1994 ◽  
pp. 525-527 ◽  
Author(s):  
K. Ohsaki ◽  
S. Yamada ◽  
H. Fuse ◽  
T. Motegi ◽  
G. Kawai ◽  
...  
Keyword(s):  
Culture Media ◽  
Solid Culture

scholarly journals Temporary immersion biorreators: efficient technique for the propagation of the ‘Pircinque’ strawberry

2019 ◽  
Vol 41 (1) ◽  
Author(s):  
Samila Silva Camargo ◽  
Leo Rufato ◽  
Maicon Magro ◽  
André Luiz Kulkamp de Souza
Keyword(s):  
Liquid Medium ◽  
Culture Medium ◽  
Culture Media ◽  
Time Factors ◽  
Efficient Technique ◽  
Control Treatment ◽  
Solid Culture ◽  
Temporary Immersion ◽  
Solid Culture Medium

Abstract The in vitro propagation technique via temporary immersion bioreactors is a tool that, through the culture in a liquid medium, allows an increase in the efficiency of seedling production. Several researches with the strawberry crop have shown greater efficiency of the system compared to the conventional process of micropropagation in solid medium. In this sense, the objective herein was to establish a protocol of multiplication and rooting of the ‘Pircinque’ strawberry, in temporary immersion bioreactors. Two distinct and independent studies were carried out, characterized by the multiplication and rooting stages of strawberry explants, newly introduced and registered in Brazil. Two culture media (MS and KNOP) were studied and, as a control treatment, the growth of the explants in solid culture medium was evaluated with the addition of 5 g L-1 of agar. Different immersion times of the culture medium were explored: five or eight times a day, for 15 minutes. The study was composed of the culture medium and immersion time factors, as well as the control (solid) treatment. It was verified that the use of temporary immersion bioreactors system is an efficient technique for the multiplication and rooting of explants of strawberry cv. Pircinque, when compared to the conventional method of micropropagation with the use of solid culture medium, making it possible to optimize the production of seedlings in biofactories. The MS liquid medium, in contact with explants of ‘Pircinque’ strawberry five times a day, increased the growth of the aerial part and the root system.

Changes in water activity of selected solid culture media throughout incubation

1992 ◽  
Vol 9 (1) ◽  
pp. 77-82
Author(s):  
G.D. García de^Fernando ◽  
O. Díaz ◽  
M. Fernández ◽  
J.A. Ordóñez
Keyword(s):  
Water Activity ◽  
Culture Media ◽  
Solid Culture

Influence des conditions de culture préalables et de la présence du gènerpoSpour la survie deSalmonella typhimuriumen eau de mer exposée à la lumière solaire

2004 ◽  
Vol 50 (5) ◽  
pp. 341-350 ◽  
Author(s):  
K Maatouk ◽  
S Zaafrane ◽  
J M Gauthier ◽  
A Bakhrouf
Keyword(s):  
Stationary Phase ◽  
Salmonella Typhimurium ◽  
Minimal Medium ◽  
High Salinity ◽  
Sea Water ◽  
Culture Media ◽  
Solid Culture ◽  
Sunlight Irradiation ◽  
Low Salinity ◽  
Isogenic Strains

The effect of sunlight exposure on Salmonella typhimurium isogenic strains harboring an rpoS gene functional (rpoS+) or not functional (rpoS–) was investigated in microcosms of sterile sea water at 20 °C. The two strains rapidly lost their ability to produce colonies on solid culture media. The detrimental action of sunlight was more important when the salinity of sea water increased. The survival of stationary phase cells was influenced by RpoS. Bacteria grown in media with high salinity or osmolarity and transferred to sea water in stationary phase were more resistant to irradiation than those grown in media with low salinity. Prior growth under oxidative (0.2 mmol/L of H2O2) or amino acid starved (minimal medium) conditions did not modify the survival of either strain when they were exposed to sunlight. Bacteria were more resistant when cells were incubated in sea water in the dark prior to being exposed to sunlight. The resistance to sunlight irradiation was also greater in clones of both strains isolated from microcosms exposed to sunlight for 90 min, then further inoculated into sea water and reexposed to sunlight.Key words: Salmonella typhimurium, sea water, sunlight, rpoS, σs.

scholarly journals Influence of the incubation conditions on culture media to optimize primary isolation of Mycobacterium bovis

2016 ◽  
Vol 37 (5Supl2) ◽  
pp. 3693
Author(s):  
Cássia Yumi Ikuta ◽  
Flávia Morato ◽  
Gisele Oliveira de Souza ◽  
Marcos Bryan Heinemann ◽  
Marcos Amaku ◽  
...  
Keyword(s):  
Mycobacterium Bovis ◽  
Bovine Tuberculosis ◽  
Culture Media ◽  
Growth Time ◽  
Solid Culture ◽  
Sodium Pyruvate ◽  
Primary Isolation ◽  
Granulomatous Lesions ◽  
Tuberculosis Diagnosis ◽  
Carbon Dioxide Co2

The isolation of Mycobacterium bovis is critical to a surveillance system for bovine tuberculosis based on detection of lesions in abattoirs. Thus, four solid culture media and three incubation conditions were investigated to elucidate which combination overcomes the others by assessing growth, time to the first appearance of colonies and their number. Ninety-seven samples of granulomatous lesions were submitted to the decontamination procedure by 1-hexadecylpyridinium chloride at 0.75% w/v, and inoculated on two egg-based media, Stonebrink’s (ST) and Löwenstein-Jensen’s with sodium pyruvate (LJp), and two agar-based media, tuberculosis blood agar (B83) and Middlebrook 7H11 medium (7H11). Each medium was incubated at 37°C for 90 days in three incubation conditions: in air, in air containing 10% carbon dioxide (CO2), and in air in slopes closed with burned hydrophobic cotton and subsequently plugged with a cork to create a microaerophilic atmosphere. The colonies appeared faster and in higher number when incubated in air containing 10% CO2 (p < 0.01), independent of media. B83 showed a faster growth and detected more isolates at 30 days of incubation, when compared to ST (0.0178), LJp (p < 0.0001) and 7H11 (p < 0.0001), though there was no difference between B83, ST and LJp at 60 and 90 days of incubation. 7H11 presented the lowest number of isolates (p < 0.0001) and a longer period for the appearance of the first colony (p < 0.001). According to our findings, the concomitant use of ST and B83 media incubated in air containing 10% CO2 increases the isolation of M. bovis in a shorter period of time, which improves bovine tuberculosis diagnosis.

Evaluation of liquid and solid culture media for the recovery and enrichment of Burkholderia cenocepacia from distilled water

2014 ◽  
Vol 41 (7) ◽  
pp. 1109-1118 ◽  
Author(s):  
Youngbeom Ahn ◽  
Jeong Myeong Kim ◽  
Hyeri Ahn ◽  
Yong-Jin Lee ◽  
John J. LiPuma ◽  
...  
Keyword(s):  
Culture Media ◽  
Burkholderia Cenocepacia ◽  
Distilled Water ◽  
Solid Culture

scholarly journals Agar Desiccation – The Causes and How to Address Them

2021 ◽  
Author(s):  
Tammy Hassel
Keyword(s):  
Moisture Content ◽  
Environmental Monitoring ◽  
Culture Media ◽  
False Negative ◽  
Data Gathering ◽  
Petri Dish ◽  
Solid Culture ◽  
Critical Data ◽  
Negative Results ◽  
The Media

Solid culture media, or agar plates, are prone to desiccation. The combination of warm, dry air and limited moisture content to achieve a solid finish leads to inevitable drying out and desiccation. Cracks in the media, a loss of volume or shrinkage away from the sides of the Petri dish are evidence of desiccation. Overall, this reduces the capability of the media to support the growth of organisms. The reduction in growth support capability is particularly so if the microorganisms deposited on the surface of the media are stressed. Why is Desiccation an Issue It is a well-known fact that microbes have three basic requirements for growth; a food source, warmth and moisture. Reducing the moisture content risks inactivating and or inhibiting growth. The purpose of monitoring for microbes through the use of solid media is to capture microorganisms from the manufacturing environment and create favourable conditions to support their optimum growth, thus allowing them to replicate and form visible colonies for inspection. Viable environmental monitoring is a challenging process to optimise for; you are looking for the chance of capturing one of the very few microorganisms present in your extensive manufacturing facility. To do so, you use solid culture media to take samples, snapshots in time, of your environment. Firstly, you have a vast space to monitor, and your monitoring activity needs to find the very few microorganisms present. If you have set your monitoring programme up suitably and you successfully capture organism present in the environment but then add desiccation you risk losing critical data. Desiccation leads to a reduction in these favourable conditions and potentially a loss of critical data and false-negative results. Desiccation of media is considered a significant quality issue as it can lead to the inhibition of growth and or cell death. The action of drying out of the media can lead to the formation of a skin on the surface. The skin formation inhibits the recovery of organisms, through «bounce» or «air bounce». As the purpose of environmental monitoring is to capture and support the growth of contaminants, this issue will result in inconclusive data gathering. Desiccation is an inevitability. Cleanroom environments are by their very nature, high airflow facilities which, as you will see below, is a primary reason for the loss of moisture from agar plates. It is, therefore, important to ensure media qualification studies include a review that post use, your media, can meet the 70% growth rate recovery as specified in USP <1227>.

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