scholarly journals Effect of Storage Time on the Physicochemical Properties of Waste Fish Oils and Used Cooking Vegetable Oils

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 101
Author(s):  
Nina Bruun ◽  
Fiseha Tesfaye ◽  
Jarl Hemming ◽  
Meheretu Jaleta Dirbeba ◽  
Leena Hupa
Keyword(s):  
Physicochemical Properties ◽  
Vegetable Oils ◽  
High Performance ◽  
Chemical Properties ◽  
Storage Period ◽  
Small Variation ◽  
Size Exclusion ◽  
Fish Oils ◽  
Renewable Fuels ◽  
Exclusion Chromatography

Waste fish oils (FOs) and used cooking vegetable oils (UCOs) are increasingly becoming alternative renewable fuels. However, different physicochemical aspects of these renewable fuels, including the effect of storage, are not well-known. In this work, the effect of the storage period on physicochemical properties of selected samples of FOs and UCOs was investigated. The bio-oils were stored at 4 °C for up to five years before each experimentation. The chemical properties were characterized using capillary gas chromatography with flame ionization detection (GC-FID) and high-performance size exclusion chromatography including an evaporative light scattering detector (HPSEC-ELSD). Water contents and acid numbers of the bio-oils were determined using the Karl Fischer (KF) titration and the ASTM D 664 methods. Furthermore, the average heating values and surface tension of the bio-oils were determined. According to the results obtained, for all bio-oil types, the concentrations of polymerized triglycerides, diglycerides, and fatty acids and monoglycerides had increased during the storage periods. The physical properties of the bio-oils also showed a small variation as a function of the storage period. The overall results observed indicate that the deterioration of the physicochemical properties of bio-oils can be controlled through storage in dark, dry, and cold conditions.

scholarly journals Soil Organic Matter Quality From Soils Cropped by Traditional Peasants

2014 ◽  
Vol 3 (4) ◽  
pp. 63
Author(s):  
Luciano Pasqualoto Canellas ◽  
Riccardo Spaccini ◽  
Natalia De Oliveira Aguiar ◽  
Fabio Lopes Olivares
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Root Growth ◽  
High Performance ◽  
Chemical Properties ◽  
Size Exclusion ◽  
Native Forest ◽  
Organic Matter Quality ◽  
African Descendants ◽  
Exclusion Chromatography

<p>In this work we have analyzed soil samples from Oxisols collected from two traditional communities, one formed by Guarany Indians at South of Brazil and other by African descendants on North of Rio de Janeiro State, Brazil. The content and fractional composition of humus was investigated and the isolated humic acids (HAs) were characterized by elemental composition, <sup>13</sup>C solid-state nuclear magnetic resonance, and high-performance size exclusion chromatography. The bioactivity of HAs was evaluated considering the effects on root growth of maize seedlings. Chemical properties from adjacent soils under native forest were used as control samples. The local field sites matching the traditional cropping requirements, were characterized by higher soil chemical fertility and soil organic matter hydrophobicity, as compared to the land plots considered as inadequate by rural peasants. The HAs from cropped soils revealed significant differences in respect to content, hydrophobicity, biostimulation and molecular dimension. Although all humic extracts promoted, both, root growth and the stimulation of lateral root emergence over control, the HAs from preferential local sites, revealed a larger bioactivity response on root stimulation even at lower concentration. The assessment of soil quality issued by local farmers, showed a valuable fitting with bio-chemical fertility indicators and SOM hydrophobicity.<strong></strong></p>

scholarly journals Periplasmic synthesis and purification of the human prolactin antagonist Δ1-11-G129R-hPRL

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Miriam F. Suzuki ◽  
Larissa A. Almeida ◽  
Stephanie A. Pomin ◽  
Felipe D. Silva ◽  
Renan P. Freire ◽  
...  
Keyword(s):  
Size Exclusion Chromatography ◽  
High Performance ◽  
Signal Sequence ◽  
Osmotic Shock ◽  
Size Exclusion ◽  
Specific Expression ◽  
E Coli ◽  
Human Prolactin ◽  
Exclusion Chromatography

AbstractThe human prolactin antagonist Δ1-11-G129R-hPRL is a 21.9 kDa recombinant protein with 188 amino acids that downregulates the proliferation of a variety of cells expressing prolactin receptors. Periplasmic expression of recombinant proteins in E. coli has been considered an option for obtaining a soluble and correctly folded protein, as an alternative to cytoplasmic production. The aim of this work was, therefore, to synthesize for the first time, the Δ1-11-G129R-hPRL antagonist, testing different activation temperatures and purifying it by classical chromatographic techniques. E. coli BL21(DE3) strain was transformed with a plasmid based on the pET25b( +) vector, DsbA signal sequence and the antagonist cDNA sequence. Different doses of IPTG were added, activating under different temperatures, and extracting the periplasmic fluid via osmotic shock. The best conditions were achieved by activating at 35 °C for 5 h using 0.4 mM IPTG, which gave a specific expression of 0.157 ± 0.015 μg/mL/A600 at a final optical density of 3.43 ± 0.13 A600. Purification was carried out by nickel-affinity chromatography followed by size-exclusion chromatography, quantification being performed via high-performance size-exclusion chromatography (HPSEC). The prolactin antagonist was characterized by SDS-PAGE, Western blotting, reversed-phase high-performance liquid chromatography (RP-HPLC) and MALDI-TOF–MS. The final product presented > 95% purity and its antagonistic effects were evaluated in vitro in view of potential clinical applications, including inhibition of the proliferation of cancer cells overexpressing the prolactin receptor and specific antidiabetic properties, taking also advantage of the fact that this antagonist was obtained in a soluble and correctly folded form and without an initial methionine.

Using HPSEC to identify NOM fraction removal and the correlation with disinfection by-product precursors

2015 ◽  
Vol 16 (2) ◽  
pp. 305-313 ◽  
Author(s):  
Euis Nurul Hidayah ◽  
Yung-Chen Chou ◽  
Hsuan-Hsien Yeh
Keyword(s):  
Humic Substances ◽  
Natural Organic Matter ◽  
High Performance ◽  
Haloacetic Acids ◽  
Size Exclusion ◽  
Formation Potential ◽  
Trihalomethane Formation Potential ◽  
Exclusion Chromatography ◽  
Alum Coagulation ◽  
Aliphatic Biopolymer

In this study high performance size exclusion chromatography (HPSEC) was used to compare an ultrafiltration (UF) membrane and alum coagulation for their capacity to remove different fractions of natural organic matter (NOM) from water. At the same time, the removal of disinfection by-product (DBP) precursors, as measured by trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP), was also detected. The results show that the UF membrane mainly removed the aliphatic biopolymer fraction, while alum coagulation mainly removed the humic substances fraction. The results of DBP precursor analysis show that more THMFP was removed by the UF membrane than HAAFP, while the reverse was true for alum coagulation. It is conjectured that the aliphatic biopolymer fraction is the major precursor for trihalomethanes (THMs), while the humic substances fraction is the major precursor for haloacetic acids (HAAs).

scholarly journals Ultra-high performance size-exclusion chromatography of synthetic polymers

2013 ◽  
Vol 36 (17) ◽  
pp. 2718-2727 ◽  
Author(s):  
Miroslav Janco ◽  
James N. Alexander ◽  
Edouard S. P. Bouvier ◽  
Damian Morrison
Keyword(s):  
Size Exclusion Chromatography ◽  
High Performance ◽  
Synthetic Polymers ◽  
Size Exclusion ◽  
Exclusion Chromatography
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