Spectral Characteristics and Functional Responses of Phospholipid Bilayers in the Terahertz Band.

Understanding the vibrational information encoded within the terahertz (THz) spectrum of biomolecules is critical for guiding the exploration of its functional responses to specific THz radiation wavelengths. This study investigated several important phospholipid components of biological membranes-distearoyl phosphatidylethanolamine (DSPE), dipalmitoyl phosphatidylcholine (DPPC), sphingosine phosphorylcholine (SPH), and lecithin bilayer-using THz time-domain spectroscopy. We observed similar spectral patterns for DPPC, SPH, and the lecithin bilayer, all of which contain the choline group as the hydrophilic head. Notably, the spectrum of DSPE, which has an ethanolamine head group, was different. Interestingly, density functional theory calculations confirmed that the absorption peak common to DSPE and DPPC at approximately 3.0 THz originated from a collective vibration of their similar hydrophobic tails. Accordingly, the cell membrane fluidity of RAW264.7 macrophages with irradiation at 3.1 THz was significantly enhanced, leading to improved phagocytosis. Our results highlight the importance of the spectral characteristics of the phospholipid bilayers when studying their functional responses in the THz band and suggest that irradiation at 3.1 THz is a potential non-invasive strategy to increase the fluidity of phospholipid bilayers for biomedical applications such as immune activation or drug administration.

Comparison of phytochemical profiles, antioxidant and antiproliferative activities in Chinese bayberry (Myrica rubra Sieb. et Zucc.) fruits.

Here, we examined the phytochemical profiles, antioxidant activity (AA), and antiproliferative activity (APA) of four Chinese bayberry (Myrica rubra Sieb. et Zucc.) pulp extracts. They were found to be rich in total phenolics content (TPC; 186.45 ± 5.42 to 498.94 ± 8.25 mg of gallic acid equiv./100 g FW) and total flavonoids content (TFC; 126.28 ± 4.18 to 194.35 ± 12.03 mg of catechin equiv./100 g FW). For all varieties, the free flavonoid/phenolic/anthocyanin contents were higher than that the bound fractions. Wild pink bayberry (WPB) displayed the highest values of TPC and TFC, and also showed the highest total antioxidant activity (TAA) as revealed by peroxyl radical scavenging capacity (PSC) (451.47 ± 8.01 µmol Vit. C equiv./100 g FW), and free cellular antioxidant activity (CAA) (184.99 ± 6.11 µmol quercetin equiv./100 g FW, no PBS wash; 117.78 ± 2.34 µmol quercetin equiv./100 g FW, PBS wash) assays. Bayberry extracts had a marked reduction in the APA of HepG2 cells, and WPB exhibited the lowest EC50 (8.50 ± 0.83 mg/ml) value, which was probably associated with cell cycle arrest and apoptosis induction. PRACTICAL APPLICATION: Chinese bayberry (Myrica rubra Sieb. et Zucc.) fruit is rich in natural phenolic compounds, which might be a functional ingredient in food and nutraceutical products. Our findings would provide a logical strategy to promote the comprehensive utilization of phenolics in bayberry fruit with both health and economy benefits.

Wild pink bayberry fruit: the effect of in vitro gastrointestinal digestion on phytochemical profiles, and antioxidant and antiproliferative activities.

The regular consumption of polyphenol-rich foods is essential to prevent the onset of diseases. Wild fruits are known to possess higher levels of bioactive components than the domesticated fruits because of the severe environmental conditions they are grown in. The aim of this study was to evaluate the phytochemical profiles, and antioxidant and antiproliferative activities of a wild pink bayberry fruit after in vitro digestion and to compare them with results obtained with a chemical extraction method. A low release of total phenolics and anthocyanins was observed after digestion compared with chemical extraction, while more flavonol contents were found by HPLC analysis. The digesta samples demonstrated low levels of extracellular antioxidant activity (EAA) and cellular antioxidant activity (CAA). However, the cellular uptake rate was increased during the in vitro digestion, and the largest value of 75.35% was obtained in the colon step. Notably, the antiproliferative activity in the colon digesta (10.14 ± 0.13 mg mL-1) was close to that of extracts (7.6 ± 0.63 mg mL-1). Pearson correlation analysis revealed that EAA and CAA were significantly correlated with TPC, while the antiproliferative activity was significantly correlated with the total contents of three flavonol compounds (quercetin, kaempferol, and myricetin). Our observations provide new insights into the bioactivity variation of whole fruits as affected by simulated digestion.

A highly efficient nanoscale tapioca starch prepared by high-speed jet for Cu2+ removal in simulated industrial effluent.

BACKGROUND: Nanoscale tapioca starch (NTS) was successfully developed by high-speed jet in our previous study. In this study, the adsorption capacity of Cu2+ onto NTS was further discussed. The optimal adsorption conditions (pH, contact time, contact temperature, initial Cu2+ concentration, and adsorbent concentration), adsorption kinetics, isotherms, and thermodynamic were also evaluated. RESULTS: The results showed that NTS exhibited excellent performance in adsorption of Cu2+ , with adsorption capacities of 122.31 mg g-1 for Cu2+ (pH 7, 0.04 g L-1 , 0.2 g L-1 , 313.15 K and 10 min). The pseudo-second-order and Langmuir isotherms models could be used to explain the adsorption kinetics and adsorption equilibrium, respectively. The thermodynamic results showed that the adsorption process was spontaneous and endothermic with an increase in entropy. Cu2+ was adsorbed onto NTS, which was confirmed by energy dispersive spectrometry analysis. CONCLUSION: These findings indicated that NTS might be an effective, environment-friendly and renewable bio-resource adsorbent for removing heavy metals in industrial effluent. © 2021 Society of Chemical Industry.

Effect of ultra­wide­band electromagnetic pulses on blood­brain barrier permeability in rats.

The restrictive nature of the blood brain barrier (BBB) brings a particular challenge to the treatment of central nervous system (CNS) disorders. The effect of ultra­wide band electromagnetic pulses (UWB­EMPs) on BBB permeability was examined in the present study in order to develop a safe and effective technology that opens the BBB to improve treatment options for CNS diseases. Rats were exposed to a single UWB­EMP at various field strengths (50, 200 or 400 kV/m) and the BBB was examined using albumin immunohistochemistry and Evans blue staining at different time periods (0.5, 3, 6 and 24 h) after exposure. The expression and distribution of zonula occludens 1 (ZO­1) were evaluated using western blotting to identify a potential mechanism underlying BBB permeability. The results showed that the BBB permeability of rats exposed to UWB­EMP increased immediately following UWM­EMP treatment and peaked between 3 and 6 h after UWB­EMP exposure, returning to pre­exposure levels 24 h later. The data suggested that UWB­EMP at 200 and 400 kV/m could induce BBB opening, while 50 kV/m UWB­EMP could not. The levels of ZO­1 in the cerebral cortex were significantly decreased at 3 and 6 h after exposure; however, no change was observed in the distribution of ZO­1. The present study indicated that UWB­EMP­induced BBB opening was field strength­dependent and reversible. Decreased expression of ZO­1 may be involved in the effect of UWB­EMP on BBB permeability.

Preventing Electromagnetic Pulse Irradiation Damage on Testis Using Selenium-rich Cordyceps Fungi. A Preclinical Study in Young Male Mice.

Networked 21st century society, globalization, and communications technologies are paralleled by the rise of electromagnetic energy intensity in our environments and the growing pressure of the environtome on human biology and health. The latter is the entire complement of environmental factors, including the electromagnetic energy and the technologies that generate them, enacting on the digital citizen in the new century. Electromagnetic pulse (EMP) irradiation might have serious damaging effects not only on electronic equipment but also in the whole organism and reproductive health, through nonthermal effects and oxidative stress. We sought to determine whether EMP exposure (1) induces biological damage on reproductive health and (2) the extent to which selenium-rich Cordyceps fungi (daily coadministration) offer protection on the testicles and spermatozoa. In a preclinical randomized study, 3-week-old male BALB/c mice were repeatedly exposed to EMP (peak intensity 200 kV/m, pulse edge 3.5 ns, pulse width 15 ns, 0.1 Hz, and 400 pulses/day) 5 days per week for four consecutive weeks, with or without coadministration of daily selenium-rich Cordyceps fungi (100 mg/kg). Testicular index and spermatozoa formation were measured at baseline and 1, 7, 14, 28, and 60 day time points after EMP exposure. The group without Cordyceps cotreatment displayed decreased spermatozoa formation, shrunk seminiferous tubule diameters, and diminished antioxidative capacity at 28 and 60 days after exposure (p < 0.05). The Cordyceps daily cotreatment alleviated the testicular damage by EMP exposure, increased spermatozoa formation, and reduced apoptotic spermatogenic cells. These observations warrant further preclinical and clinical studies as an innovative approach for potential protection against electromagnetic radiation in the current age of networked society and digital citizenship.