Comparative study on the stability of crude and refined rice bran oil during long‐term storage at room temperature

2007 ◽  
Vol 109 (3) ◽  
pp. 198-205 ◽  
Author(s):  
Samia Mezouari ◽  
Karl Eichner
Keyword(s):  
Comparative Study ◽  
Rice Bran ◽  
Room Temperature ◽  
Rice Bran Oil ◽  
Long Term Storage ◽  
The Stability ◽  
Term Storage

scholarly journals Changes of salivary biomarkers under different storage conditions: effects of temperature and length of storage

2018 ◽  
Vol 29 (1) ◽  
pp. 94-111 ◽  
Author(s):  
Tomás Barranco ◽  
Asta Tvarijonaviciute ◽  
Damián Escribano ◽  
Fernando Tecles ◽  
José J Cerón ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Room Temperature ◽  
Storage Conditions ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Long Term Storage ◽  
Reducing Ability ◽  
Trolox Equivalent ◽  
The Stability ◽  
Term Storage

Introduction: In this report, we aimed to examine the stability of various analytes in saliva under different storage conditions. Materials and methods: Alpha-amylase (AMY), cholinesterase (CHE), lipase (Lip), total esterase (TEA), creatine kinase (CK), aspartate aminotransferase (AST), lactate dehydrogenase (LD), lactate (Lact), adenosine deaminase (ADA), Trolox equivalent antioxidant capacity (TEAC), ferric reducing ability (FRAS), cupric reducing antioxidant capacity (CUPRAC), uric acid (UA), catalase (CAT), advanced oxidation protein products (AOPP) and hydrogen peroxide (H2O2) were colorimetrically measured in saliva obtained by passive drool from 12 healthy voluntary donors at baseline and after 3, 6, 24, 72 hours, 7 and 14 days at room temperature (RT) and 4 ºC, and after 14 days, 1, 3 and 6 months at – 20 ºC and – 80 ºC. Results: At RT, changes appeared at 6 hours for TEA and H2O2; 24 hours for Lip, CK, ADA and CUPRAC; and 72 hours for LD, Lact, FRAS, UA and AOPP. At 4 ºC changes were observed after 6 hours for TEA and H2O2; 24 hours for Lip and CUPRAC; 72 hours for CK; and 7 days for LD, FRAS and UA. At – 20 ºC changes appeared after 14 days for AST, Lip, CK and LD; and 3 months for TEA and H2O2. At – 80 ºC observed changes were after 3 months for TEA and H2O2. Conclusions: In short-term storage, the analytes were more stable at 4 ºC than at room temperature, whereas in long-term storage they were more stable at - 80 ºC than at – 20 ºC.

Human plasma stability during handling and storage: impact on NMR metabolomics

The Analyst ◽  
2014 ◽  
Vol 139 (5) ◽  
pp. 1168-1177 ◽  
Author(s):  
Joana Pinto ◽  
M. Rosário M. Domingues ◽  
Eulália Galhano ◽  
Cristina Pita ◽  
Maria do Céu Almeida ◽  
...  
Keyword(s):  
Human Plasma ◽  
Room Temperature ◽  
Storage Conditions ◽  
Plasma Composition ◽  
Long Term Storage ◽  
Short And Long Term ◽  
The Stability ◽  
And Storage ◽  
Term Storage

The stability of human plasma composition was investigated by NMR, considering different collection tubes, time at room temperature (RT), short- and long-term storage conditions and up to 5 consecutive freeze–thaw cycles.

NANOEMULSIONS BASED ON LIPOIC ACID DERIVATIVES WITH VARIOUS ALCOHOLS: PRODUCTION AND INFLUENCE ON FUNCTIONAL ACTIVITY OF PLATELETS

2020 ◽  
pp. 461-464
Author(s):  
A. Sinebryukhova ◽  
A. Shipelova ◽  
E. Darnotuk ◽  
A. Chekanov ◽  
O. Baranova ◽  
...  
Keyword(s):  
Particle Size ◽  
Arachidonic Acid ◽  
Lipoic Acid ◽  
Encapsulation Efficiency ◽  
Room Temperature ◽  
Optimal Conditions ◽  
Pluronic F68 ◽  
Long Term Storage ◽  
Term Storage

The optimal conditions were selected for obtaining homogeneous nanoemulsions (NE) of lipoic acid conjugates (LA-conjugates) based on Pluronic F68 (1,8%) with a particle size not exceeding 400 nm, characterized by 97±2% encapsulation efficiency of substances in nanoparticles (NP). A heterogeneous NE (polydispersity index, PDI>0,3) with the derivative of LA and myo-inositol based on phosphatidylcholine (PC, C = 3 mg/ml) was also obtained consisting of 2 particle fractions: 20–70 nm (27%) and 122–212 nm (73%). The obtained NEs with LA-conjugates based on Pluronic F68 and PC were stable during long-term storage (more than 12 months) at room temperature. The effect of the obtained NEs of LA-conjugates on platelet aggregation (Pt) caused by arachidonic acid (AA) was determined, and a mechanism of their action was proposed.

Stability and epimerisation behaviour of ergot alkaloids in various solvents

2008 ◽  
Vol 1 (1) ◽  
pp. 67-78 ◽  
Author(s):  
M. Hafner ◽  
M. Sulyok ◽  
R. Schuhmacher ◽  
C. Crews ◽  
R. Krska
Keyword(s):  
Degradation Products ◽  
Ergot Alkaloids ◽  
Carbonate Buffer ◽  
Long Term Storage ◽  
No Formation ◽  
Temperature Levels ◽  
The Stability ◽  
Extraction Mixture ◽  
Term Storage

In this paper the stability and degree of epimerisation of six major ergot alkaloids at three different temperature levels (-20 °C, +4 °C and +20 °C) over periods of 18 hours and six weeks is reported for the first time. The behaviour of ergometrine, ergocornine, ergocristine, α-ergocryptine, ergosine and ergotamine was thoroughly studied in seven solvents which are employed for the preparation of calibrants and extraction mixtures, respectively. Moreover, the stability of the ergot alkaloids was tested in different cereal extracts (rye, wheat, barley, oats) for 1, 2 and 6 days. Of the toxins tested, the ergopeptide-type toxins ergosine, ergotamine, ergocornine, α-ergocryptine and ergocristine showed similar behaviour patterns. The simple lysergic acid derivative ergometrine was more stable and showed hardly any epimerisation to ergometrinine, with the sum of both epimers remaining constant in all seven solvents. The ergopeptides tested show variable epimerisation tendencies, and were also less stable during six weeks at 20 °C. Ergosine showed the highest degree of epimerisation (43% after 6 weeks at 20 °C). In general, the order of epimerisation promotion was methanol/dichloromethane > acetonitrile/buffer > extraction mix > stabilising solution > acetonitrile >> chloroform. Long-term storage at room temperature can only be carried out in chloroform, which showed no epimerisation for all toxins even at 20 °C and also kept the sum of R and S forms constant, which indicates no formation of aci-epimers or other degradation products. Long-term storage of ergot alkaloids in acetonitrile, the most convenient solvent with respect to HPLC analysis, should be carried out at temperatures of -20 °C or below. The constant epimer ratio of all ergot alkaloids in the extraction mixture acetonitrile/ammonium carbonate buffer (200 mg/l; 92:8, v/v) during an HPLC run (18 hours) demonstrates the stability of the toxins in this extraction mixture.

The Carbonate-Hardening Lime Construction Material Properties Formation during their Long-Term Storage and Use under Normal Conditions

2019 ◽  
Vol 974 ◽  
pp. 187-194 ◽  
Author(s):  
Nikolay V. Lyubomirskiy ◽  
Tamara A. Bakhtina ◽  
Alexander S. Bakhtin ◽  
Sergey I. Fedorkin
Keyword(s):  
Construction Material ◽  
Construction Materials ◽  
Materials Properties ◽  
Long Term Storage ◽  
Efficiency Assessment ◽  
The Stability ◽  
Term Storage ◽  
Long Storage ◽  
Quality Construction

This paper presents the lime binding forced carbonate-hardening materials properties formation study and determins the stability of these properties during long-term storage and use under normal conditions. The tests showed these materials stability properties over time, confirming the strength and density growth of the test samples after long storage due to the calcium hydroxide recrystallization completion into calcium carbonate processes. Also, the results of the samples carbonate hardening study under natural conditions during 18 months are presented. An efficiency assessment of forced carbonate hardening as one of the methods of recycling technogenic CO2 in order to reduce its emissions in the atmosphere, and, in the result, to obtain high-quality construction materials has been made.

scholarly journals HMGB1 concentration measurements in trauma patients: assessment of pre-analytical conditions and sample material

2019 ◽  
Vol 26 (1) ◽  
Author(s):  
William Ottestad ◽  
Ingrid N. Rognes ◽  
Erlend Skaga ◽  
Cassandra Frisvoll ◽  
Guttorm Haraldsen ◽  
...  
Keyword(s):  
Western Blot ◽  
Room Temperature ◽  
Trauma Patients ◽  
Plasma Samples ◽  
Sample Material ◽  
Limits Of Agreement ◽  
Freeze Thaw ◽  
Long Term Storage ◽  
Term Storage

Abstract Background HMGB1 is a mediator of systemic inflammation in sepsis and trauma, and a promising biomarker in many diseases. There is currently no standard operating procedure for pre-analytical handling of HMGB1 samples, despite that pre-analytical conditions account for a substantial part of the overall error rate in laboratory testing. We hypothesized that the considerable variations in reported HMGB1 concentrations and kinetics in trauma patients could be partly explained by differences in pre-analytical conditions and choice of sample material. Methods Trauma patients (n = 21) admitted to a Norwegian Level I trauma center were prospectively included. Blood was drawn in K2EDTA coated tubes and serum tubes. The effects of delayed centrifugation were evaluated in samples stored at room temperature for 15 min, 3, 6, 12, and 24 h respectively. Plasma samples subjected to long-term storage in − 80 °C and to repeated freeze/thaw cycles were compared with previously analyzed samples. HMGB1 concentrations in simultaneously acquired arterial and venous samples were also compared. HMGB1 was assessed by standard ELISA technique, additionally we investigated the suitability of western blot in both serum and plasma samples. Results Arterial HMGB1 concentrations were consistently lower than venous concentrations in simultaneously obtained samples (arterial = 0.60 x venous; 95% CI 0.30–0.90). Concentrations in plasma and serum showed a strong linear correlation, however wide limits of agreement. Storage of blood samples at room temperature prior to centrifugation resulted in an exponential increase in plasma concentrations after ≈6 h. HMGB1 concentrations were fairly stable in centrifuged plasma samples subjected to long-term storage and freeze/thaw cycles. We were not able to detect HMGB1 in either serum or plasma from our trauma patients using western blotting. Conclusions Arterial and venous HMGB1 concentrations cannot be directly compared, and concentration values in plasma and serum must be compared with caution due to wide limits of agreement. Although HMGB1 levels in clinical samples from trauma patients are fairly stable, strict adherence to a pre-analytical protocol is advisable in order to protect sample integrity. Surprisingly, we were unable to detect HMGB1 utilizing standard western blot analysis.

Synthesis Optimization of Guanidinium Dinitramide (GDN)

2020 ◽  
Vol 20 (11) ◽  
pp. 6855-6861
Author(s):  
Wooram Kim ◽  
Mijeong Park ◽  
Jong-Ki Jeon ◽  
Youngmin Jo
Keyword(s):  
Maximum Yield ◽  
Resonance Structure ◽  
Kcal Mole ◽  
Additional Advantage ◽  
Long Term Storage ◽  
Ft Ir ◽  
The Stability ◽  
Infrared Frequencies ◽  
Term Storage

Dinitramide anion [−N(NO2)2] salt composed of resonance structure is a plausible oxidizing agents, as efficient propellant. Among them, guanidinium dinitramide (GDN) is an organic compound improving the stability against moisture, as well long term storage. An additional advantage composed guanidinium ion is the reaction efficient via the decomposed by-product during pyrognostics, maximum yield of 99%. The types of GDN (GDN-I, II, III, IV, V) were synthesized using several starting material such as guanidine acetate, chloride, carbonate, nitrate and sulfate under hydrodeprivation. In this work, the intermediates formed in these processes were closely identified and their thermal properties, and chemical structure were examined. The absorption peaks by Fourier transform infrared (FT-IR) were found guanidinium infrared frequencies (3452, 3402, 3354, 3278, 1642 cm−1) and dinitramide infrared frequencies (3208, 1570, 1492, 1416, 1337, 1179, 1000 cm−1). The activation energy of GDN samples were obtained Ea = 53.26 Kcal/mole (GDN-I), 50.94 Kcal/mole (GDN-II), 52.34 Kcal/mole (GDN-III), 62.19 Kcal/mole (GDN-IV), 55.32 Kcal/mole (GDN-V) from exothermic at over 153°C.

Investigation into the State of Preservation of the E.T. Browne Collection of Hydromedusae

1990 ◽  
Vol 70 (2) ◽  
pp. 477-480
Author(s):  
S.J. Moore
Keyword(s):  
Comparative Study ◽  
The State ◽  
Tabular Form ◽  
Long Term Storage ◽  
Term Storage

A comparative study of the state of preservation of hydromedusae has been made based on a collection that has been preserved for 80–90 years. A report has been compiled in tabular form concerning the state of the collection in relation to the present pH of the preserving fluid. Recommendations are made based upon which fixative and preserving fluids have proved to be best for long-term storage.

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