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BACKGROUND:Pectins have unique properties and great potential to become an indispensable component of cryoprotective environment for platelet freezing.OBJECTIVE:To investigate the possibility of including pectins (apple pectin AU-701, tanacetan) into the composition of a cryoprotective solution for platelets during low-temperature storage.MATERIALS AND METHODS:Samples of platelet concentrates (PC) were frozen under the protection of complex solutions and stored in an electric freezer at -80 °C for 1 and 6 months.RESULT:The study showed that of the basic cryoprotectants, the best effect in the preservation of PC was with dimethylacetamide (DMAC). The use of pectins as an additive to the base solution of DMAC statistically improves the preservation of PC after exposure to low temperatures (-80 ° C) for 30 and 180 days.CONCLUSIONS:We conclude that DMAC is more promising as a basis for the development of a new combined cryoprotectant for PC freezing. Moreover, the chemical structure of pectin determines the level of its cryoprotective action in relation to the preservation of PC.
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This content will become publicly available on January 21, 2026
Reviving diversity: cryoprotectants and culturing methods enhance recovery of mammalian gut microbes from field samples
The field of microbial ecology is increasingly recognizing the need for methods to isolate and culture gut microbes to better understand how these microorganisms impact animal physiology, especially in mammalian hosts. Currently, there is a lack of clear methods to store microbial samples for cultivability, especially when samples are collected from the field, transported to the laboratory, and preserved under long-term storage for weeks to months compared to mere days in the biomedical field. Here, the cecal contents of groundhogs (Marmota monax) were processed and stored with or without various preservation solutions at −80 °C for at least 2 months. All microbial samples were then grown in distinct nutrient media in liquid and plate conditions and were incubated under anaerobic and aerobic environments. Treatment comparisons revealed that the samples stored in preservation solutions containing 1 or more cryoprotectants provided the greatest and most consistent bacterial densities. To test the long-term storage efficacy of the preservation solutions, we inventoried taxonomic identities and abundances of these cultures using 16S rRNA amplicon sequencing. Our findings highlight that: (1) preserved samples containing cryoprotectants exhibited the highest microbial richness and diversity and resembled the original cecal samples the most when grown under anaerobic conditions; and (2) the effect of individual animal identity was detectable in the membership of cultured communities, irrespective of preservation solutions. Our study is the first to demonstrate the importance of preservation solutions containing multiple cryoprotectants for long-term storage and further microbial culturing and novel isolation. Understanding and improving storage methods that preserve microbial physiology and conserve their compositional diversity is essential for field-collected samples useful in mammalian microbiome and culturomics studies, promoting a better comprehension of the identity and function of wild host-associated microbiomes.
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- Award ID(s):
- 1942587
- PAR ID:
- 10581714
- Editor(s):
- Alston, Jesse
- Publisher / Repository:
- Oxford Academic Publishing
- Date Published:
- Journal Name:
- Journal of Mammalogy
- ISSN:
- 0022-2372
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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