RESUMEN
The effect of fenugreek (Trigonella foenum-graecum L.) seed extracts (FSEs) on the structure of duck myofibrillar protein (MP) oxidation was researched via particle size, zeta potential, Fourier transform infrared (FTIR), fluorescence spectroscopy, SDS-PAGE, and scanning electron microscopy (SEM) in the Fenton oxidation system. FSE (0.3 mg/mL) could scavenge 58.79% of the hydroxyl radical and possessed good antioxidation. FSE could retard the oxidation of MP, and the carbonyl formation and total sulfhydryl loss of MP decreased by 42.00% and 105.94%, respectively, after 4.67% of FSE treatment. SDS-PAGE results showed that 0.67% and 2.67% of FSE decreased the strength of the myosin heavy chain (MHC) and actin bands of the oxidized MP, respectively. The FSE changed the secondary structures of the MP and promoted the unfolding of the MP structure and the transformation from α-helix to ß-turn. When treated with 0.67% of FSE, the hydrophobicity of the MP declined by 26.14%, and solubility was improved by 37.21% compared with the oxidation group. After 0.67% of FSE treatment, the particle size and zeta potential of the MP returned to the level of the blank group. Scanning electron microscopy revealed that FSE improved the apparent morphology of the MP. Overall, FSE had positive effects on the antioxidation of the duck MP, and it could improve the structure and characteristics of the MP. It is hoped that FSE could be considered as a natural antioxidant to retard the oxidation of the MP in meat products.
RESUMEN
Egg-white protein has an abundance of hydrophobic amino acids and could be a potential emulsifier after modification. Here, egg-white protein was modified via ultrasonic and transglutaminase treatments to destroy the globular structure. The egg-white protein gel particles (EWP-GPs) were prepared and then a novel highly stable EWP-chitosan double-layer emulsion was constructed. When ultrasonic treatment was applied at 240 W and TGase (20 U/g EWP) treatment, the EWP-GPs had a low particle size and good emulsification performance. The particle size of EWP-GPs was a minimum of 287 nm, and the polymer dispersity index (PDI) was 0.41. The three-phase contact angle (θo/w) of EWP-GPs was 79.6° (lower than 90°), performing with good wettability. Based on these results, the EWP-chitosan double-layer emulsion was prepared through the EWP-GPs being treated with 240 W ultrasound, TGase, and chitosan in this study. When the double-layer emulsion had 0.6% (v/v) chitosan, the zeta potential of the double-layer emulsion was -1.1 mV and the double-layer emulsion had a small particle size (56.87 µm). The creaming index of double-layer emulsion at 0.6% (v/v) chitosan was 16.3% and the droplets were dispersed uniformly. According to the rheological results, the storage modulus (G') was larger than the loss modulus (Gâ³) in the whole frequency, indicating the formation of an elastic gel network structure in the emulsion. It is hoped to develop a novel food-grade stabilizer and a stable double-layer emulsion, providing new environment-friendly processing in hen egg products and delivery systems.
Asunto(s)
Quitosano , Aminoácidos , Animales , Pollos , Proteínas del Huevo/química , Emulsiones , Femenino , Geles , TransglutaminasasRESUMEN
Although an important greenhouse gas, methane flux in hilly forest ecosystems remains unclear. By using closed-path eddy covariance systems, methane flux was measured continuously from 2017 to 2019 in a mixed plantation in the Xiaolangdi area of the Yellow River in North China. The methane flux footprint and its diurnal and monthly variations were analysed, and its characteristics on rainy days are discussed. The results showed that: (a) the observation data were reliable with good spatial representation (b) The methane flux in the mixed plantation ecosystem had obvious diurnal and seasonal variations: the monthly average diurnal variation of the methane flux had a single-peak; the methane flux value was source in the daytime and sink at night. The daily mean maximum value of methane flux in growing season was lower than that in non-growing season with the maximum value appearing in March, and the minimum value in October. (c) The forest is an atmospheric CH4 source with the annual emission in 2017 of (3.31 g C·m-2·year -1) >2019 (2.94 g C·m-2·year-1) >2018 (2.81 g C·m-2·year -1), and the main influencing factor was precipitation. Rainfall affected CH4 flux with a lag period of approximately three days. Rainfall also changed the balance of CH4 flux between sink or source according to precipitation intensity and frequency.
RESUMEN
The study aimed to explore the roles of alprostadil combined with edaravone in inflammation, oxidative stress and Pulmonary function in patients with traumatic hemorrhagic shock (HS). 80 patients with traumatic HS treated in Feicheng Hospital Affiliated to Shandong First Medical University and Tai'an City Central Hospital from January 2018 to January 2022 were enrolled and divided into observation group (n=40) and control group (n=40) according to the randomized control method. Patients in the control group were given alprostadil alone (5 g alprostadil + 10 mL normal saline) in addition to conventional treatment, while those in the observation group received edaravone (30 mg edaravone + 250 mL normal saline) on the basis of treatment in the control group. The patients in both groups were treated via intravenous infusion once a day for 5 days. 24 hours (h) after resuscitation, venous blood were collected to detect serum biochemical indicators such as blood urea nitrogen (BUN), aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Enzyme-linked immunosorbent assay (ELISA) was conducted to determine serum inflammatory factors. Lung lavage fluid was collected to examine pulmonaryfunction indicators such as myeloperoxidase (MPO) and matrix metalloproteinase-9 (MMP-9) activity and to observe the oxygenation index (OI). Blood pressure was measured at admission and 24 h after surgery. The observation group had significantly lowered serum BUN, AST and ALT (p<0.05), the content of serum interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) as well as oxidative stress indexes like superoxide dismutase (SOD) and malondialdehyde (MDA) (p<0.05) and pulmonary function indicators (p<0.05) but overtly increased content of SOD and OI. Furthermore, the blood pressure in the observation group dropped to 30 mmHg at admission and rose to the normal range. Alprostadil combined with edaravone effectively reduces inflammatory factors and improves oxidative stress and pulmonary function in patients with traumatic HS, whose efficacy is significantly better than that of alprostadil alone.