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Journal of Microbiological Methods Jun 2015Studies of the gut microbiome have become increasingly common with recent technological advances. Gut microbes play an important role in human and animal health, and gut...
Studies of the gut microbiome have become increasingly common with recent technological advances. Gut microbes play an important role in human and animal health, and gut microbiome analysis holds great potential for evaluating health in wildlife, as microbiota can be assessed from non-invasively collected fecal samples. However, many common fecal preservation protocols (e.g. freezing at -80 °C) are not suitable for field conditions, or have not been tested for long-term (greater than 2 weeks) storage. In this study, we collected fresh fecal samples from captive spider monkeys (Ateles geoffroyi) at the Columbian Park Zoo (Lafayette, IN, USA). The samples were pooled, homogenized, and preserved for up to 8 weeks prior to DNA extraction and sequencing. Preservation methods included: freezing at -20 °C, freezing at -80 °C, immersion in 100% ethanol, application to FTA cards, and immersion in RNAlater. At 0 (fresh), 1, 2, 4, and 8 weeks from fecal collection, DNA was extracted and microbial DNA was amplified and sequenced. DNA concentration, purity, microbial diversity, and microbial composition were compared across all methods and time points. DNA concentration and purity did not correlate with microbial diversity or composition. Microbial composition of frozen and ethanol samples were most similar to fresh samples. FTA card and RNAlater-preserved samples had the least similar microbial composition and abundance compared to fresh samples. Microbial composition and diversity were relatively stable over time within each preservation method. Based on these results, if freezers are not available, we recommend preserving fecal samples in ethanol (for up to 8weeks) prior to microbial extraction and analysis.
Topics: Animals; Atelinae; Cryopreservation; Ethanol; Feces; Humans; Microbiota; Preservation, Biological; Sequence Analysis, DNA; Specimen Handling
PubMed: 25819008
DOI: 10.1016/j.mimet.2015.03.021 -
Biotechnic & Histochemistry : Official... 1991Two nonaqueous fixatives, composed of fluorocarbon solvents with dissolved osmium tetroxide, were used to determine the feasibility of preserving the mucous coat in...
Two nonaqueous fixatives, composed of fluorocarbon solvents with dissolved osmium tetroxide, were used to determine the feasibility of preserving the mucous coat in bovine and rat trachea for light and electron microscopy. Aqueous fixatives, while providing excellent cytological preservation, wash away the mucous lining, precluding ultrastructural analysis. Inclusion of ruthenium red or alcian blue within aqueous fixative improved retention of mucus, but provided incomplete, patchy results. Fixation with nonaqueous fluorocarbon solvent and dissolved osmium tetroxide preserved a continuous mucous epiphase layer above a clear hypophase layer. Subcomponents of the mucus included an electron dense surface layer, interrupted patches of mucus above the surface layer and electron dense membrane-like material within the mucus. This method of fixation will preserve mucus for light, scanning and transmission electron microscopy, using either intratracheal or immersion methods of fixation. The latter would enable use of materials from large animal models, autopsy or an abattoir.
Topics: Animals; Cattle; Fixatives; Fluorocarbons; Male; Microscopy, Electron; Mucus; Osmium Tetroxide; Preservation, Biological; Rats; Trachea
PubMed: 1832970
DOI: 10.3109/10520299109109965 -
The British Journal of Venereal Diseases Apr 1979Studies of Neisseria gonorrhoeae are difficult to perform because of the organism's poor survival in vitro. To solve this problem we tried to preserve the organism by a...
Studies of Neisseria gonorrhoeae are difficult to perform because of the organism's poor survival in vitro. To solve this problem we tried to preserve the organism by a gelatin-disc method. The rate of survival and changes of variations in some biochemical properties of eight strains of N. gonorrhoeae were followed for three years. These studies proved that preservation was satisfactory with only a 1/10 reduction of the living cells. Another trial showed that the organism survived for over six months after being frozen at -20 degrees C. The colonial types, agglutination against red cells from rabbit and guinea pig, and antibiotic susceptibility to penicillin, chloramphenicol, tetracycline, kanamycin, and streptomycin did not change after three years' preservation.
Topics: Anti-Bacterial Agents; Gelatin; Microbial Sensitivity Tests; Neisseria gonorrhoeae; Preservation, Biological; Temperature; Time Factors
PubMed: 109165
DOI: 10.1136/sti.55.2.90 -
Pathologie (Heidelberg, Germany) Aug 2022Fluid collections are gaining more importance for research and teaching, but they are facing preservation problems. In the case of historical collections, the methods of... (Review)
Review
BACKGROUND
Fluid collections are gaining more importance for research and teaching, but they are facing preservation problems. In the case of historical collections, the methods of fixation and preservation are poorly documented. The liquid used is unknown. In order to ensure the preservation of such collections, it is essential to have available a preservation liquid that is compatible with the most common historical liquids and techniques.
MATERIALS AND METHODS
A universal liquid based on historical recipes was developed for such problematic preparations.
RESULTS
The use of distilled water, glycerin and ethanol (80%) in a ratio of 10:6:1 offers a good alternative that is harmless to the health of the user. It can be used for colour-preserving conserved preparations and for pure ethanol and formaldehyde preparations and is recommended as a universal solution for preparations in unknown preservation liquids.
Topics: Preservation, Biological; Formaldehyde; Ethanol; Glycerol
PubMed: 36222924
DOI: 10.1007/s00292-022-01138-5 -
Sabouraudia Dec 1979Details are given of a method, first described in 1962, for preservation of fungi in anhydrous silica gel. It is shown that the procedure is suitable for use with...
Details are given of a method, first described in 1962, for preservation of fungi in anhydrous silica gel. It is shown that the procedure is suitable for use with dermatophytes, yeasts and other fungi of medical importance and that they may be preserved for periods of 5 years or more.
Topics: Fungi; Gels; Humans; Mycoses; Preservation, Biological; Silicon Dioxide; Species Specificity; Spores, Fungal
PubMed: 232575
DOI: 10.1080/00362177985380611 -
Methods in Molecular Biology (Clifton,... 2019Previous writings in the area of natural history casting are exiguous especially in reference to the casting of fluid preserved specimens. The following attempts to... (Review)
Review
Previous writings in the area of natural history casting are exiguous especially in reference to the casting of fluid preserved specimens. The following attempts to recognize the importance of casts as natural history specimens and determine why this method of preservation might be used. This piece goes on to instruct the reader how to create their own casts using a simple method and materials which are readily available to all.
Topics: Biological Specimen Banks; Humans; Preservation, Biological; Specimen Handling
PubMed: 30539444
DOI: 10.1007/978-1-4939-8935-5_16 -
Cryobiology Jun 1985The results of this paper illustrate that trehalose partially preserves inner mitochondrial membrane integrity after freeze-thawing and freeze-drying with subsequent...
The results of this paper illustrate that trehalose partially preserves inner mitochondrial membrane integrity after freeze-thawing and freeze-drying with subsequent rehydration in water. The 2,4-dinitrophenol stimulation of ATPase activity was used as a criterion for membrane integrity. The results show that ATPase activity of lyophilized-rehydrated mitochondria was stimulated up to two to three times.
Topics: Animals; Disaccharides; Freeze Drying; In Vitro Techniques; Intracellular Membranes; Microscopy, Electron; Mitochondria, Liver; Preservation, Biological; Rats; Trehalose
PubMed: 3996019
DOI: 10.1016/0011-2240(85)90177-4 -
Molecular Ecology Resources Mar 2012Transcriptome sequencing with next-generation sequencing technologies has the potential for addressing many long-standing questions about the biology of sponges....
Transcriptome sequencing with next-generation sequencing technologies has the potential for addressing many long-standing questions about the biology of sponges. Transcriptome sequence quality depends on good cDNA libraries, which requires high-quality mRNA. Standard protocols for preserving and isolating mRNA often require optimization for unusual tissue types. Our aim was assessing the efficiency of two preservation modes, (i) flash freezing with liquid nitrogen (LN₂) and (ii) immersion in RNAlater, for the recovery of high-quality mRNA from sponge tissues. We also tested whether the long-term storage of samples at -80 °C affects the quantity and quality of mRNA. We extracted mRNA from nine sponge species and analysed the quantity and quality (A260/230 and A260/280 ratios) of mRNA according to preservation method, storage time, and taxonomy. The quantity and quality of mRNA depended significantly on the preservation method used (LN₂) outperforming RNAlater), the sponge species, and the interaction between them. When the preservation was analysed in combination with either storage time or species, the quantity and A260/230 ratio were both significantly higher for LN₂-preserved samples. Interestingly, individual comparisons for each preservation method over time indicated that both methods performed equally efficiently during the first month, but RNAlater lost efficiency in storage times longer than 2 months compared with flash-frozen samples. In summary, we find that for long-term preservation of samples, flash freezing is the preferred method. If LN₂ is not available, RNAlater can be used, but mRNA extraction during the first month of storage is advised.
Topics: Animals; Porifera; Preservation, Biological; RNA, Messenger; Sequence Analysis, DNA; Time Factors
PubMed: 22136287
DOI: 10.1111/j.1755-0998.2011.03097.x -
Antonie Van Leeuwenhoek 1986Cultures of Thiobacillus ferrooxidans and Thiobacillus thiooxidans, used in biohydrometallurgical processes of economic importance, are very difficult to preserve by...
Cultures of Thiobacillus ferrooxidans and Thiobacillus thiooxidans, used in biohydrometallurgical processes of economic importance, are very difficult to preserve by conventional methods. Hence, to preserve the cultures with their activity intact, various techniques were tried, after determining their respective activity in terms of Iron Oxidation Rate (IOR) and Sulfur Oxidation Rate (SOR). Among the methods tested, along with the recommended method of serial transfer in a liquid medium, were methods such as lyophilization, storage in a liquid nitrogen and mixing with sterile, inert carriers like lignite or chalcopyrite ores. After a period check-up at 4 months and 8 months storage, it was found that out of these methods, mixing with sterile ore followed by storage at 8 degrees C, kept both types of activities intact. The temperature of storage was observed to have a definite effect on activity, in that when the preserved cultures were stored at 8 degrees C, the activity was retained, whereas at 28-30 degrees C (RT) storage, the activity of all the cultures preserved by various techniques, dropped significantly.
Topics: Acidithiobacillus thiooxidans; Freeze Drying; Iron; Nitrogen; Oxidation-Reduction; Preservation, Biological; Sulfur; Temperature; Thiobacillus
PubMed: 3524447
DOI: 10.1007/BF00429315 -
Journal of Microbiological Methods Apr 2014Microbiological work requires a reliable source of cultures that are not only well defined and taxonomically determined, but are also adequately preserved without...
Microbiological work requires a reliable source of cultures that are not only well defined and taxonomically determined, but are also adequately preserved without changes in their morphological, physiological and genetic traits. Here we describe an easy, cost effective and rapid method for reliably preserving filamentous fungi on cellophane pieces at -80°C for use in laboratory culture collections.
Topics: Freezing; Fungi; Mycology; Preservation, Biological
PubMed: 24566130
DOI: 10.1016/j.mimet.2014.02.009