Biochemical composition and amino acid profiles of Nannochloropsis granulata algal biomass before and after supercritical fluid CO2 extraction at two processing temperatures

Silk proteins have many advantageous components including proteins and pigments. The proteins—sericin and fibroin—have been widely studied for medical applications due to their good physiochemical properties and biological activities. Various strains of cocoon display different compositions such as amino-acid profiles and levels of antioxidant activity. Therefore, the objectives of this study were to find a suitable silk protein extraction method to obtain products with chemical and biological properties suitable as functional foods in two strains of Bombyx mori silk cocoon (Nangsew strains; yellow cocoon) and Samia ricini silk cocoon (Eri strains; white cocoon) extracted by water at 100 °C for 2, 4, 6 and 8 h. The results showed that Nangsew strains extracted for 6 h contained the highest amounts of protein, amino acids, total phenolics (TPC) and total flavonoids (TFC), plus DPPH radical-scavenging activity, ABTS radical scavenging capacity, and ferric reducing antioxidant power (FRAP), anti-glycation, α-amylase and α-glucosidase inhibition. The longer extraction time produced higher concentrations of amino acids, contributing to sweet and umami tastes in both silk strains. It seemed that the bitterness decreased as the extraction time increased, resulting in improvements in the sweetness and umami of silk-protein extracts.

Download Full-text

Enhanced Electrical Characteristics of Ge nMOSFET by Supercritical Fluid CO2 Treatment with H2O2 Cosolvent

IEEE Electron Device Letters ◽

10.1109/led.2021.3068336 ◽

2021 ◽

pp. 1-1

Author(s):

Dun-Bao Ruan ◽

Kuei-Shu Chang-Liao ◽

Guan-Ting Liu ◽

Yu-Chuan Chiu ◽

Kai-Jhih Gan ◽

...

Keyword(s):

Supercritical Fluid ◽

Electrical Characteristics ◽

Supercritical Fluid Co2 ◽

Co2 Treatment

Download Full-text

Deep fluids and their role in hydrocarbon migration and oil deposit formation exemplified by supercritical СO2

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691021000013 ◽

2021 ◽

pp. 1-11

Author(s):

Sara LIFSHITS

Keyword(s):

Supercritical Fluid ◽

Oil And Gas ◽

Gas Permeability ◽

Sedimentary Rocks ◽

Source Rocks ◽

Reservoir Properties ◽

Hydrocarbon Migration ◽

Geological Processes ◽

Before And After ◽

Oil Source

ABSTRACT Hydrocarbon migration mechanism into a reservoir is one of the most controversial in oil and gas geology. The research aimed to study the effect of supercritical carbon dioxide (СО2) on the permeability of sedimentary rocks (carbonates, argillite, oil shale), which was assessed by the yield of chloroform extracts and gas permeability (carbonate, argillite) before and after the treatment of rocks with supercritical СО2. An increase in the permeability of dense potentially oil-source rocks has been noted, which is explained by the dissolution of carbonates to bicarbonates due to the high chemical activity of supercritical СО2 and water dissolved in it. Similarly, in geological processes, the introduction of deep supercritical fluid into sedimentary rocks can increase the permeability and, possibly, the porosity of rocks, which will facilitate the primary migration of hydrocarbons and improve the reservoir properties of the rocks. The considered mechanism of hydrocarbon migration in the flow of deep supercritical fluid makes it possible to revise the time and duration of the formation of gas–oil deposits decreasingly, as well as to explain features in the formation of various sources of hydrocarbons and observed inflow of oil into operating and exhausted wells.

Download Full-text

Alteration of serum amino acid profiles by dietary adenine supplementation inhibits fatty liver development in rats

Scientific Reports ◽

10.1038/s41598-020-79234-w ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Hiroki Nishi ◽

Daisuke Yamanaka ◽

Masato Masuda ◽

Yuki Goda ◽

Koichi Ito ◽

...

Keyword(s):

Amino Acid ◽

Fatty Liver ◽

Causative Factor ◽

Amino Acid Profile ◽

Liver Development ◽

Concentration Data ◽

Amino Acid Profiles ◽

Arginine Deficiency ◽

Branched Chain ◽

Tag Accumulation

AbstractStudies on animal models have demonstrated that feeding a low-arginine diet inhibits triacylglycerol (TAG) secretion from the liver, resulting in marked fatty liver development in rats. Here, we first showed that culturing hepatocytes in the medium mimicking the serum amino acid profile of low-arginine diet-fed rats induced TAG accumulation in the cells, indicating that the specific amino acid profile caused TAG accumulation in hepatocytes. Dietary adenine supplementation completely recovered hepatic TAG secretion and abolished hepatic TAG accumulation in rats. A comprehensive non-linear analysis revealed that inhibition of hepatic TAG accumulation by dietary adenine supplementation could be predicted using only serum amino acid concentration data. Comparison of serum amino acid concentrations indicated that histidine, methionine, and branched-chain amino acid (BCAA) concentrations were altered by adenine supplementation. Furthermore, when the serum amino acid profiles of low-arginine diet-fed rats were altered by modifying methionine or BCAA concentrations in their diets, their hepatic TAG accumulation was abolished. Altogether, these results suggest that an increase in methionine and BCAA levels in the serum in response to dietary arginine deficiency is a key causative factor for hepatic TAG accumulation, and dietary adenine supplementation could disrupt this phenomenon by altering serum amino acid profiles.

Download Full-text