scholarly journals Preservation of Azotobacter chroococcum vegetative cells in dry polymers

2014 ◽  
Vol 20 (2) ◽  
pp. 201 ◽  
Author(s):  
Daniel Rojas-Tapias ◽  
Oriana Ortega Sierra ◽  
Diego Rivera Botía ◽  
Ruth Bonilla
Keyword(s):  
Storage Conditions ◽  
Azotobacter Chroococcum ◽  
Bacterial Degradation ◽  
Protective Agent ◽  
Degradation Rates ◽  
Different Temperatures ◽  
And Storage ◽  
Temperature Time ◽  
Long Term Preservation

We studied the preservation of Azotobacter chroococcum C26 using three dry polymers: carrageenin, sodium alginate, and HPMC, using a method of accelerated degradation. Bacterial viability, as response variable, was measured at three temperatures in four different times, which was followed by calculation of bacterial degradation rates. Results showed that temperature, time of storage, and protective agent influenced both viability and degradation rates (P;lt;0.05). We observed, using the Arrhenius thermodynamic model, that the use of polymers increased the activation energy of bacterial degradation compared to control. We obtained thermodynamic models for each polymer, based on the Arrhenius equation, which predicted the required time for thermal degradation of the cells at different temperatures. Analysis of the models showed that carrageenin was the best polymer to preserve A. chroococcum C26 since ~ 900 days are required at 4 ºC to reduce its viability in two log units. We conclude, therefore, that long-term preservation of A. chroococcum C26 using dry polymers is suitable under adequate preservation and storage conditions.

scholarly journals Changes of Physicochemical Properties of Starch Syrups Recommended for Winter Feeding of Honeybees during Storage

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 374
Author(s):  
Teresa Szczęsna ◽  
Ewa Waś ◽  
Piotr Semkiw ◽  
Piotr Skubida ◽  
Katarzyna Jaśkiewicz ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Physicochemical Parameters ◽  
Storage Temperature ◽  
Storage Conditions ◽  
Different Temperatures ◽  
And Storage ◽  
Bee Colonies ◽  
Temperature Time ◽  
Winter Feeding

The aim of this study was to determine the influence of storage temperature and time on physicochemical parameters of starch syrups recommended for the winter feeding of bee colonies. The studies included commercially available three starch syrups and an inverted saccharose syrup that were stored at different temperatures: ca. 20 °C, 10–14 °C, and ca. 4 °C. Physicochemical parameters of fresh syrups (immediately after purchase) and syrups after 3, 6, 9, 12, 15, 18, 21, and 24 months of storage at the abovementioned temperatures were measured. It was observed that the rate of unfavorable changes in chemical composition of starch syrups and the inverted saccharose syrup, mainly the changes in the 5-hydroxymethylfurfural (HMF) content, depended on the type of a syrup and storage conditions (temperature, time). Properties of tested starch syrups intended for winter feeding of bees stored at ca. 20 °C maintained unchanged for up to 6 months, whereas the same syrups stored at lower temperatures (10–14 °C) maintained unchanged physicochemical parameters for about 12 months. In higher temperatures, the HMF content increased. To date, the influence of this compound on bees has not been thoroughly investigated.

scholarly journals Seed longevity of maize conserved under germplasm bank conditions for up to 60 years

2021 ◽  
Author(s):  
Filippo Guzzon ◽  
Maraeva Gianella ◽  
Jose Alejandro Velazquez Juarez ◽  
Cesar Sanchez Cano ◽  
Denise E Costich
Keyword(s):  
Seed Germination ◽  
Plant Genetic Resources ◽  
Seed Viability ◽  
Storage Conditions ◽  
Seed Longevity ◽  
Germplasm Bank ◽  
Significant Difference ◽  
Different Temperatures ◽  
Germination Experiments

Abstract Background and Aims The long-term conservation of seeds of plant genetic resources is of key importance for food security and preservation of agrobiodiversity. Nevertheless, there is scarce information available about seed longevity of many crops under germplasm bank conditions. Methods Through germination experiments as well as the analysis of historical monitoring data, we studied the decline in viability manifested by 1000 maize (Zea mays subsp. mays) seed accessions conserved for an average of 48 years at the CIMMYT germplasm bank, the largest maize seedbank in the world, under two cold storage conditions: an active (–3 °C; intended for seed distribution) and a base conservation chamber (–15 °C; for long-term conservation). Key Results Seed lots stored in the active chamber had a significantly lower and more variable seed germination, averaging 81.4 %, as compared with the seed lots conserved in the base chamber, averaging 92.1 %. The average seed viability detected in this study was higher in comparison with that found in other seed longevity studies on maize conserved under similar conditions. A significant difference was detected in seed germination and longevity estimates (e.g. p85 and p50) among accessions. Correlating seed longevity with seed traits and passport data, grain type showed the strongest correlation, with flint varieties being longer lived than floury and dent types. Conclusions The more rapid loss of seed viability detected in the active chamber suggests that the seed conservation approach, based on the storage of the same seed accessions in two chambers with different temperatures, might be counterproductive for overall long-term conservation and that base conditions should be applied in both. The significant differences detected in seed longevity among accessions underscores that different viability monitoring and regeneration intervals should be applied to groups of accessions showing different longevity profiles.

Should phosphatidylethanol be currently analysed using whole blood, dried blood spots or both?

2019 ◽  
Vol 57 (5) ◽  
pp. 617-622 ◽  
Author(s):  
Van Long Nguyen ◽  
Michael Fitzpatrick
Keyword(s):  
Whole Blood ◽  
Blood Cells ◽  
Dried Blood Spots ◽  
Storage Conditions ◽  
Ethanol Metabolism ◽  
Clinical Use ◽  
Blood Spots ◽  
Comparative Review ◽  
And Storage

Abstract Phosphatidylethanol (PEth) are phospholipids produced through non-oxidative ethanol metabolism. They accumulate in red blood cells and have been traditionally analysed in whole blood as potential biomarkers for moderate to long-term alcohol consumption. More recently, their analysis in dried blood spots has been gaining favour, namely, due to the ease in sampling, transport and storage conditions required. This paper aims at providing a short comparative review between analysing PEth in whole blood and dried blood spots and the potential pitfalls that researchers may face when setting up PEth testing for clinical use.

scholarly journals Managing Moholy : László Moholy-Nagy's photograms in the collections of the Art Institute of Chicago and George Eastman House

2021 ◽  
Author(s):  
D. Anne Maryanski
Keyword(s):  
Detailed Analysis ◽  
Storage Conditions ◽  
Experimental Techniques ◽  
Collections Management ◽  
Policies And Procedures ◽  
Unique Nature ◽  
Entire Career ◽  
Long Term Preservation

The Art Institute of Chicago (AIC) and George Eastman House International Museum of Photography and Film (GEH) have acquired substantial collections of László Moholy-Nagy's work, spanning his entire career. Using four photograms by Moholy-Nagy, two from each institution, as representative examples, this thesis examines how the AIC and GEH have dealt with his work through an examination of the acquisition, exhibition, publication, preservation, and conservation of his photographs. The unique nature of Moholy-Nagy's photograms, coupled with the myriad experimental techniques he employed in their production, has necessitated that the AIC and GEH establish policies and procedures for the care and long-term preservation of photographic objects of this nature, through the development and implementation of exhibition and loan standards as well as highly monitored storage conditions. This thesis includes an overview of the museums, a detailed analysis of each photogram, and a discussion of the collections management concerns that these objects raise.

scholarly journals Long-term hydrophilization of polydimethylsiloxane (PDMS) for capillary filling microfluidic chips

2019 ◽  
Vol 24 (1) ◽  
Author(s):  
Farzin Jahangiri ◽  
Tuuli Hakala ◽  
Ville Jokinen
Keyword(s):  
Cold Storage ◽  
Storage Temperature ◽  
Microfluidic Channel ◽  
Vibration Band ◽  
Microfluidic Chips ◽  
Thermally Activated ◽  
Capillary Filling ◽  
Different Temperatures ◽  
Long Term Preservation

AbstractWe present a simple and facile method for long-term preservation of hydrophilicity of oxygen plasma-hydrophilized poly (dimethylsiloxane) (PDMS) by cold storage. We show that storage under temperature of − 80 °C can maintain superhydrophilicity of plasma-exposed PDMS for at least 100 days. Storage at − 15 °C and at 22 °C room temperature (RT) is shown to exhibit, respectively, about half and full recovery of the original hydrophobicity after 100 days in storage. Furthermore, we investigated the implications of the cold storage for microfluidic applications, the capillary filling rate and the ability of the flow to bypass geometrical obstacles in a microfluidic channel. It is shown that the preservation of capillary filling properties of microchannels is in close agreement with the contact angle (CA) measurements and that the colder the storage temperature, the better the capillary filling capability of the channels is preserved. We ascribe the significantly reduced recovery rate to reduced thermally activated relaxation phenomena such as diminished diffusion of low molecular weight species (LMW) in the polymer matrix at colder temperatures. This is supported by ATR-FTIR measurements of the OH vibration band over time for samples stored at different temperatures.

scholarly journals Encapsulation of Lactobacillus acidophilus La-5 and Bifidobacterium Bb-12 by spray drying and evaluation of its resistance in simulated gastrointestinal conditions, thermal treatments and storage conditions

2018 ◽  
Vol 48 (6) ◽  
Author(s):  
Graciele Lorenzoni Nunes ◽  
Mariana Heldt Motta ◽  
Alexandre José Cichoski ◽  
Roger Wagner ◽  
Édson Irineu Muller ◽  
...  
Keyword(s):  
Thermal Resistance ◽  
Lactobacillus Acidophilus ◽  
Encapsulation Efficiency ◽  
Storage Conditions ◽  
Thermal Treatments ◽  
Spray Dryer ◽  
Gastrointestinal Conditions ◽  
Different Temperatures ◽  
And Storage ◽  
Gastrointestinal Simulation

ABSTRACT: Lactobacillus acidophillus La-5 (ML) and Bifidobacterium Bb-12 (MB) microparticles were produced at different temperatures by spray dryer. The influence of different temperatures on the viability, encapsulation efficiency, water activity and moisture were evaluated. Microparticles that presented more viability were submitted to thermal resistance, gastrointestinal simulation, storage stability, morphology and particle size analyses. Drying temperature of 130°C showed higher encapsulation efficiency, 84.61 and 79.73% for Lactobacillus acidophillus (ML) and Bifidobacterium Bb-12 (MB) microparticles, respectively. In the evaluation of thermal resistance and gastrointestinal simulation, the microparticles of Lactobacillus acidophillus La-5 (ML) presented higher survival than Bifidobacterium Bb-12 (MB) under these conditions. In storage viability only the Lactobacillus acidophillus La-5 (ML) microparticles remained viable at all evaluated temperatures during the 120 days. The particle sizes reported were 4.85 for Lactobacillus acidophillus La-5 (ML) and 8.75 for Bifidobacterium Bb-12 (MB), being in agreement with the desired values for products obtained by spray dryer. Finally, the Lactobacillus acidophilus La-5 (ML) microparticles were shown to be more resistant under the conditions evaluated in this study.

scholarly journals Textural Changes of Asparagus in Relation to Delays in Cooling and Storage Conditions

1992 ◽  
Vol 2 (3) ◽  
pp. 378-381 ◽  
Author(s):  
Luis Hernández-Rivera ◽  
Robert Mullen ◽  
Marita Cantwell
Keyword(s):  
Shear Force ◽  
Storage Temperature ◽  
Storage Conditions ◽  
Asparagus Officinalis ◽  
Shear Transfer ◽  
Textural Changes ◽  
And Storage ◽  
Temperature Time ◽  
Storage Temperatures

Asparagus (Asparagus officinalis L.) spears (cv. UC 157) trimmed to 20 cm were cooled 0, 4, 8, 12, 16, and 20 hours after harvest and evaluated for resistance to shear at 5 and 10 cm above the cut end immediately after cooling and during storage at 0.5, 2.5, and 5C. Resistance to shear increased during cooling delays and with time in storage. Initial cooling delays and simulated marketing conditions (transfer to 15C for 1 day) were the principal causes of increased resistance to shear. A 4-hour cooling delay resulted in an average 40% increase in resistance to shear. Transfer to 15C for 1 day resulted in a greater increase in shear force in the rapidly cooled than in the delayed-cooled spears. Increases in resistance to shear during storage varied from 0% to 50% and depended on the storage temperature, time, and the initial cooling delay. Spears trimmed to a green base showed less increase in shear force after storage than did spears trimmed to a white base. The visual quality of asparagus stored for 14 days was similar (excellent) among spears from different storage temperatures and between green- and white-base spears. Storage quality after 24 days had decreased more in spears stored at 5C than at 2.5 or 0.5C, and more in the green-base than the white-base spears.

scholarly journals Effects of High-Temperature Storage on the Elasticity Modulus of an Epoxy Molding Compound

Materials ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 684
Author(s):  
Ruifeng Li ◽  
Daoguo Yang ◽  
Ping Zhang ◽  
Fanfan Niu ◽  
Miao Cai ◽  
...  
Keyword(s):  
High Temperature ◽  
Elasticity Modulus ◽  
Glassy State ◽  
Storage Conditions ◽  
Material Structure ◽  
Epoxy Molding Compound ◽  
Molding Compound ◽  
Different Temperatures ◽  
Temperature Storage

Changes in the elasticity modulus of an epoxy molding compound (EMC), an electronic packaging polymer, under high-temperature air storage conditions, are discussed in this study. The elasticity modulus of EMC had two different compositions (different filling contents) under different temperatures (175, 200, and 225 °C) and aging times (100, 500, and 1500 h), which were analyzed by using dynamic mechanic analysis technology. The results revealed that the elasticity modulus increased in the thermal aging process, with an increase in the temperature and the aging time. The increments of the glassy and rubbery states were similar. However, the growing rate was significantly different, and the growth of the rubbery state was significantly higher than that of the glassy state. The filling content influenced the degree of aging of the materials significantly. At a low filling content, long-term aging under high temperatures completely changed the material structure, and the mechanical properties of the polymer were reduced.

scholarly journals ANTIOXIDANT PROPERTIES AND FRUIT QUALITY DURING LONG-TERM STORAGE OF “ROCHA” PEAR: EFFECTS OF MATURITY AND STORAGE CONDITIONS

2010 ◽  
Vol 33 (1) ◽  
pp. 1-20 ◽  
Author(s):  
FILIPE J.P. SILVA ◽  
MARIA HELENA GOMES ◽  
FERNANDA FIDALGO ◽  
JOSÉ A. RODRIGUES ◽  
DOMINGOS P.F. ALMEIDA
Keyword(s):  
Fruit Quality ◽  
Antioxidant Properties ◽  
Storage Conditions ◽  
Long Term Storage ◽  
And Storage ◽  
Term Storage

scholarly journals Use of 2-aminoethanesulfonic acid (taurine) for cryopreservation and storage of Siberian sturgeon sperm

2021 ◽  
Vol 273 ◽  
pp. 03010
Author(s):  
Konstantin Kovalev ◽  
Olga Dokina ◽  
Natalia Pronina ◽  
Dmitry Balashov ◽  
Aleksandra Krasilnikova
Keyword(s):  
Fertility Preservation ◽  
Siberian Sturgeon ◽  
Taurine Concentration ◽  
And Storage ◽  
Long Term Preservation

The research aimed to determine the effect of different taurine concentrations on the duration of sperm fertility preservation and the results of further use during cryopreservation. The taurine was injected into the sperm of the Siberian sturgeon by various methods under conditions of low positive temperatures. Immediately after preparation, the taurine was injected into native sperm at concentrations of 0.01, 0.05, and 0.1 mmol/ml. Two methods of introducing taurine into native sperm were tested: 1 (dry method) - adding taurine powder directly to native sperm and 2 (wet method) - adding taurine dissolved in saline to native sperm. The studies have shown that injections of taurine in an amount of 0.05 - 0.1 mmol/ml both dry and wet can be recommended as the method of long-term preservation of the native sperm of Siberian sturgeon viability. While storing Siberian sturgeon sperm for further cryopreservation the optimal taurine concentration is 0.01 mmol/ml.

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