SCREW-CAPPED BOTTLES IN THE PREPARATION AND STORAGE OF CULTURE MEDIA

The Lancet ◽  
1933 ◽  
Vol 222 (5738) ◽  
pp. 433-436 ◽  
Author(s):  
J.E. Mccartney
Keyword(s):  
2013 ◽  
Vol 80 (3) ◽  
pp. 374-381 ◽  
Author(s):  
Marina Golowczyc ◽  
Carlos Vera ◽  
Mauricio Santos ◽  
Cecilia Guerrero ◽  
Paula Carasi ◽  
...  

Galacto-oligosaccharides (GOS) are prebiotics that have a beneficial effect on human health by promoting the growth of probiotic bacteria in the gut. GOS are commonly produced from lactose in an enzymatic reaction catalysed by β-galactosidase, named transglycosylation. Lactose is the main constituent of whey permeate (WP), normally wasted output from the cheese industry. Therefore, the main goal of this work was to optimise the synthesis of GOS in WP using β-galatosidase from Aspergillus oryzaea. WP and whey permeate enzymatically treated (WP-GOS) were used as culture media of Lactobacillus plantarum 299v. Lb. plantarum 299v attained the stationary phase in approximately 16 h, reaching 3·6 and 4·1×108 CFU/ml in WP and WP-GOS, respectively. The in situ synthesised GOS were not consumed during growth. No significant differences were observed in the growth kinetics of microorganisms in both media. After fermentation, microorganisms were dehydrated by freeze-drying and spray-drying and stored. The recovery of microorganisms after fermentation, dehydration and storage at 4 °C for at least 120 d was above 108 CFU/g. These studies demonstrated that WP is an appropriate substrate for the synthesis of GOS and the obtained product is also adequate as culture medium of Lb. plantarum 299v. The coexistence of GOS and dehydrated viable probiotic microorganisms, prepared using an effluent as raw material, represents the main achievement of this work, with potential impact in the development of functional foods.


2004 ◽  
Vol 67 (2) ◽  
pp. 252-255 ◽  
Author(s):  
SHIAO MEI LEE ◽  
JINRU CHEN

Previous studies conducted in our laboratory revealed that Escherichia coli O157:H7 cells capable of producing colanic acid (CA), the acidic polysaccharide of mucoid slime, had increased tolerance to sublethal heat and the extreme pH of microbiological culture media. This study was undertaken to determine the effect of CA on the fate of E. coli O157:H7 during the processing and storage of an acid food: yogurt. Pasteurized and homogenized whole milk was inoculated with a wild-type E. coli O157:H7, its CA-deficient mutant, or a mixture (1:1) of the two strains. Set yogurt was processed from the contaminated milk and stored at 4° and 15°C for 3 weeks. Samples of milk and yogurt were withdrawn during processing and storage and analyzed for total plate counts and populations of E. coli O157:H7 and starter cultures. The results showed that E. coli O157: H7 survived longer in yogurt stored at 15°C than at 4°C. Cells of E. coli O157:H7 deficient in CA production died off more rapidly than those of the parent strain. This suggests that CA plays a role in protecting cells of E. coli O157:H7 from stress during the processing and storage of set yogurt.


2021 ◽  
Vol 43 (1) ◽  
Author(s):  
Karina Guollo ◽  
Américo Wagner Junior ◽  
Carlos Kosera Neto ◽  
Juliana Cristina Radaelli ◽  
Welida Mayara Tomazoni Keller

Abstract Sete-capote tree, a neglected species, has great ecological, cultural and potential economic importance, however, studies for this and other native species of the Myrtaceae family are still scarce. The objective of this study was to elucidate aspects of pollen germination and viability of this specie. For the experiment, pollen from flowers in pre and post anthesis was used, which was dehydrated in a chamber containing silica, for different periods. For germination tests, different concentrations of sucrose, boric acid and calcium nitrate were used. After obtaining germination results above 80%, the pollen grains were stored in refrigerator (5 °C), freezer (-17 °C), liquid nitrogen (-147 °C) and natural environment (± 25 °C), evaluating monthly the germination, until total loss of viability. For germination, it was recommend using pollen from flowers in post-anthesis, dehydrated for 24 hours in a silica chamber. The culture medium should contain 12% sucrose (C12H22O11), 10% boric acid (H3BO3) and 20% calcium nitrate (Ca(NO3)2) to obtain high germinative percentages. In addition, pollen presents orthodox behavior and when stored in liquid nitrogen, remains viable for 30 days.


2000 ◽  
Vol 38 (10) ◽  
pp. 3872-3875 ◽  
Author(s):  
M. J. Crespo ◽  
M. L. Abarca ◽  
F. J. Cabañes

Freezing at −80°C, lyophilization, preservation in distilled water, and storage in different culture media were performed in order to find a suitable method that allowed a prolonged storage ofMalassezia spp. Freezing at −80°C was the only method successful at maintaining all species.


2021 ◽  
Vol 937 (2) ◽  
pp. 022015
Author(s):  
G Urban ◽  
O.Y. Krotova ◽  
K. C. Savenkov ◽  
A Chernyshkov ◽  
M. N. Savenkova

Abstract The leptospirosis vaccine is the main method of preventing the occurrence and spread of leptospirosis. Compliance with the standards of manufacturing, labeling, and storage is mandatory for immunological preparations. All stages of vaccine production must comply with the rules established by the Ministry of Industry and Trade and ensure its safety for humans. The article presents epidemiological data on leptospirosis in the Russian Federation in the period from 2013 to 2018. A method for producing a vaccine against human leptospirosis is described. The leptospirosis vaccine is polyvalent using membrane technologies and semi-synthetic culture media. It eliminates the use of foreign protein and does not require cleaning. The vaccine is an opalescent liquid with sediment and a pH of 7.2-7.6 and it is not allowed to contain live leptospira. Four strains are used and a new strain has been developed and implemented. Vaccination is carried out according to epidemiological indicators. Leptospirosis suspension forms specific immunity for 1 year. During the production of the updated vaccine, it was necessary to study the virulent properties of the strains. Moreover, analyze the formation of specific antibodies to leptospira in the new vaccine and in the vaccine currently used. From 2018 to 2020, 5 series of experimental vaccines in the form of a 0.5 ml suspension were produced.


2013 ◽  
Vol 2 (1s) ◽  
pp. 10 ◽  
Author(s):  
Rasoul Shafiei ◽  
Frank Delvigne ◽  
Phillipe Thonart

Downstream processes have great influences on bacterial starter production. Different modifications occur to cellular compounds during freeze-drying process and storage of bacterial starters. Consequently, viability and culturability (multiplication capacity) undergo some changes. In this study, the effects of freeze-drying process and storage conditions were examined on cell envelope integrity, respiration and culturability of <em>Acetobacter senegalensis</em>. Freezing of cells protected with mannitol (20% w/w) did not affect cell multiplication and respiration considerably; however, 19% of cells showed compromised cell envelope after freezing. After drying, 1.96&times;10<sup>11</sup> CFU/g were enumerated, indicating that about 34% of the cells could survive and keep their culturability. Drying of the cells induced further leakage in cell envelope and finally 81% of cells appeared as injured ones; however, 87% of the dried cells maintained their respiration capacity. Storage temperature had significant effect on cell multiplication ability; higher storage temperature (35&deg;C) caused 8.59-log reduction in cell culturability after nine-month period of storage. Collapse of cell envelop integrity and respiration was observed at 35&deg;C. At lower storage temperature (4&deg;C), the culturability decreased about one-log reduction after nine months. Cell envelope integrity was subjected to minor changes during a period of nine month-storage at 4&deg;C whereas a heterogeneous population of cells with different respiration capacity emerged at 4&deg;C. These results indicate that a major part of cells undergone drying process and storage entered into viable but non-culturable state. In addition, usage of different culture media didn&rsquo;t improve resuscitation. Besides, it seems that sub-lethal damages to cell envelope caused uptake of propidium iodide, however these kinds of injuries could not impress cell multiplications and respiration.


2019 ◽  
Vol 22 (09) ◽  
pp. 55-60
Author(s):  
S.T. Orlova ◽  
◽  
A.A. Sidorchuk ◽  
T.V. Grebennikova ◽  
◽  
...  
Keyword(s):  

Author(s):  
R. C. Gonzalez

Interest in digital image processing techniques dates back to the early 1920's, when digitized pictures of world news events were first transmitted by submarine cable between New York and London. Applications of digital image processing concepts, however, did not become widespread until the middle 1960's, when third-generation digital computers began to offer the speed and storage capabilities required for practical implementation of image processing algorithms. Since then, this area has experienced vigorous growth, having been a subject of interdisciplinary research in fields ranging from engineering and computer science to biology, chemistry, and medicine.


Author(s):  
Marek Malecki ◽  
James Pawley ◽  
Hans Ris

The ultrastructure of cells suspended in physiological fluids or cell culture media can only be studied if the living processes are stopped while the cells remain in suspension. Attachment of living cells to carrier surfaces to facilitate further processing for electron microscopy produces a rapid reorganization of cell structure eradicating most traces of the structures present when the cells were in suspension. The structure of cells in suspension can be immobilized by either chemical fixation or, much faster, by rapid freezing (cryo-immobilization). The fixation speed is particularly important in studies of cell surface reorganization over time. High pressure freezing provides conditions where specimens up to 500μm thick can be frozen in milliseconds without ice crystal damage. This volume is sufficient for cells to remain in suspension until frozen. However, special procedures are needed to assure that the unattached cells are not lost during subsequent processing for LVSEM or HVEM using freeze-substitution or freeze drying. We recently developed such a procedure.


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