Improvement of Unsaturated Fatty Acid Production from Porphyridium cruentum Using a Two-Phase Culture System in a Photobioreactor with Light-Emitting Diodes (LEDs).

In this study, the culture conditions for Porphyridium cruentum were optimized to obtain the maximum biomass and lipid productions. The eicosapentaenoic acid content was increased by pH optimization. P. cruentum was cultured with modified F/2 medium in 14-L photobioreactors using a two-phase culture system, in which the green (520 nm) and red (625 nm) light-emitting diodes (LEDs) were used during the first and second phases for biomass production and lipid production, respectively. Various parameters, including aeration rate, light intensity, photoperiod, and pH were optimized. The maximum biomass concentration of 0.91 g dcw/l was obtained with an aeration rate of 0.75 vvm, a light intensity of 300 µmol m-2s-1, and a photoperiod of 24:0 h. The maximum lipid production of 51.8% (w/w) was obtained with a light intensity of 400 µmol m-2s-1 and a photoperiod of 18:6 h. Additionally, the eicosapentaenoic acid and unsaturated fatty acid contents reached 30.6% to 56.2% at pH 6.0.

Innovative Approach of Non-Thermal Plasma Application for Improving the Growth Rate in Chickens.

As an innovative technology in biological applications-non-thermal plasma technique-has recently been applied to living cells and tissues. However, it is unclear whether non-thermal plasma treatment can directly regulate the growth and development of livestock. In this study, we exposed four-day-incubated fertilized eggs to plasma at 11.7 kV for 2 min, which was found to be the optimal condition in respect of highest growth rate in chickens. Interestingly, plasma-treated male chickens conspicuously grew faster than females. Plasma treatment regulated the reactive oxygen species homeostasis by controlling the mitochondrial respiratory complex activity and up-regulating the antioxidant defense system. At the same time, growth metabolism was improved due to the increase of growth hormone and insulin-like growth factor 1 and their receptors expression, and the rise of thyroid hormones and adenosine triphosphate levels through the regulation of demethylation levels of growth and hormone biosynthesis-related genes in the skeletal muscles and thyroid glands. To our knowledge, this study was the first to evaluate the effects of a non-thermal plasma treatment on the growth rate of chickens. This safe strategy might be beneficial to the livestock industry.

MicroRNA-7450 regulates non-thermal plasma-induced chicken Sertoli cell apoptosis via adenosine monophosphate-activated protein kinase activation.

Non-thermal plasma treatment is an emerging innovative technique with a wide range of biological applications. This study was conducted to investigate the effect of a non-thermal dielectric barrier discharge plasma technique on immature chicken Sertoli cell (SC) viability and the regulatory role of microRNA (miR)-7450. Results showed that plasma treatment increased SC apoptosis in a time- and dose-dependent manner. Plasma-induced SC apoptosis possibly resulted from the excess production of reactive oxygen species via the suppression of antioxidant defense systems and decreased cellular energy metabolism through the inhibition of adenosine triphosphate (ATP) release and respiratory enzyme activity in the mitochondria. In addition, plasma treatment downregulated miR-7450 expression and activated adenosine monophosphate-activated protein kinase α (AMPKα), which further inhibited mammalian target of rapamycin (mTOR) phosphorylation in SCs. A single-stranded synthetic miR-7450 antagomir disrupted mitochondrial membrane potential and decreased ATP level and mTOR phosphorylation by targeting the activation of AMPKα, which resulted in significant increases in SC lethality. A double-stranded synthetic miR-7450 agomir produced opposite effects on these parameters and ameliorated plasma-mediated apoptotic effects on SCs. Our findings suggest that miR-7450 is involved in the regulation of plasma-induced SC apoptosis through the activation of AMPKα and the further inhibition of mTOR signaling pathway.

Non-thermal plasma treatment improves chicken sperm motility via the regulation of demethylation levels.

The quality of avian semen is an important economic trait in poultry production. The present study examines the in vitro effects of non-thermal dielectric barrier discharge plasma on chicken sperm to determine the plasma conditions that can produce the optimum sperm quality. Exposure to 11.7 kV of plasma for 20 s is found to produce maximum sperm motility by controlling the homeostasis of reactive oxygen species and boosting the release of adenosine triphosphate and respiratory enzyme activity in the mitochondria. However, prolonged exposure or further increase in plasma potential impairs the sperm quality in a time- and dose-dependent manner. Optimal plasma treatment of sperm results in upregulated mRNA and protein expression of antioxidant defense-related and energetic metabolism-related genes by increasing their demethylation levels. However, 27.6 kV of plasma exerts significant adverse effects. Thus, our findings indicate that appropriate plasma exposure conditions improve chicken sperm motility by regulating demethylation levels of genes involved in antioxidant defense and energetic metabolism.

Lethality of inappropriate plasma exposure on chicken embryonic development.

In this study, we examined the effects of non-thermal dielectric barrier discharge plasma on embryonic development in chicken eggs in order to determine the optimal level of plasma exposure for the promotion of embryonic growth. We exposed developing chicken embryos at either Hamburger-Hamilton (HH) stage 04 or HH 20 to plasma at voltages of 11.7 kV to 27.6 kV. Our results show exposure at 11.7 kV for 1 min promoted chicken embryonic development, but exposure to more duration and intensity of plasma resulted in dose-dependent embryonic death and HH 20 stage embryos survive longer than those at stage HH 04. Furthermore, plasma exposure for 4 min increased the production of reactive oxygen species (ROS) and inactivated the nuclear factor erythroid 2-related factor 2 (NRF2)-antioxidant response signaling pathway, resulting in suppression of antioxidant enzymes in the skeletal muscle tissue of the dead embryos. We also found decreased levels of adenosine triphosphate production and reductions in the expression levels of several growth-related genes and proteins. These findings indicate that inappropriate plasma exposure causes dose-dependent embryonic death via excessive accumulation of ROS, NRF2-antioxidant signaling pathway disruption, and decreased growth factor expression.

Growth-inducing effects of argon plasma on soybean sprouts via the regulation of demethylation levels of energy metabolism-related genes.

This study was conducted to determine the effects of argon plasma on the growth of soybean [Glycine max (L.) Merr.] sprouts and investigate the regulation mechanism of energy metabolism. The germination and growth characteristics were modified by argon plasma at different potentials and exposure durations. Upon investigation, plasma treatment at 22.1 kV for 12 s maximized the germination and seedling growth of soybean, increasing the concentrations of soluble protein, antioxidant enzymes, and adenosine triphosphate (ATP) as well as up-regulating ATP a1, ATP a2, ATP b1, ATP b2, ATP b3, target of rapamycin (TOR), growth-regulating factor (GRF) 1-6, down-regulating ATP MI25 mRNA expression, and increasing the demethylation levels of the sequenced region of ATP a1, ATP b1, TOR, GRF 5, and GRF 6 of 6-day-old soybean sprouts. These observations indicate that argon plasma promotes soybean seed germination and sprout growth by regulating the demethylation levels of ATP, TOR, and GRF.

Removal of ethylene from air stream by adsorption and plasma-catalytic oxidation using silver-based bimetallic catalysts supported on zeolite.

Dynamic adsorption of ethylene on 13X zeolite-supported Ag and Ag-M(x)O(y) (M: Co, Cu, Mn, and Fe), and plasma-catalytic oxidation of the adsorbed ethylene were investigated. The experimental results showed that the incorporation of Ag into zeolite afforded a marked enhancement in the adsorptivity for ethylene. The addition of transition metal oxides was found to have a positive influence on the ethylene adsorption, except Fe(x)O(y). The presence of the additional metal oxides, however, appeared to somewhat interrupt the diffusion of ozone into the zeolite micro-pores, leading to a decrease in the plasma-catalytic oxidation efficiency of the ethylene adsorbed there. Among the second additional metal oxides, Fe(x)O(y) was able to reduce the emission of ozone during the plasma-catalytic oxidation stage while keeping a high effectiveness for the oxidative removal of the adsorbed ethylene. The periodical treatment consisting of adsorption followed by plasma-catalytic oxidation may be a promising energy-efficient ethylene abatement method.

Fabrication of an electrically conductive mixed self-assembled monolayer and its application in an electrochemical immunosensor.

Oligophenylethynylene thiol containing carboxylic acid in the tail group as a conducting wire bioreceptor was synthesized, and then its electrical property was investigated from the measurement of scanning tunneling microscopy (STM). Mixed self-assembled monolayer (SAM) consisting of 4-(2-(4-acetylthio)phenyl)ethynyl) benzoic acid (APBA) and butanethiol was fabricated in order to improve the electrical conductivity owing to the molecular orientation. We have examined the molecular orientation and the electrochemical activity of mixed SAM via X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). Especially, the prepared mixed SAM used as a bioreceptor in electrochemical prostate specific antigen (PSA) immunosensor showed higher electrochemical activity than that of the other SAMs.

Fabrication of line-shaped embossing structure by holographic lithography and its application to electronic device.

Holographic lithography has been an efficient and versatile method to fabricate nanosize patterned devices during past several years. This technique is based on the interference of UV-laser beams for patterning regular arrays of fine features without the use of mask as used in conventional lithography. Simple gratings and two-dimensional dot arrays has been fabricated by using the interference principle. Using this technique, we fabricated line-shaped embossing gold (Au) structure on silicon substrates. Towards the characterization of fabricated line-shaped Au nano-structure Field Effect Scanning Electron Microscopy (FE-SEM) is used and our results clearly show the fine structure of fabricated Au lines. Further characterization towards our patterned substrates we used Atomic Force Microscopy (AFM) for analysis of Au patterned lines. A bioelectronic device consisting of cysteine modified azurin was fabricated where the protein was covalently immobilized on the nano-patterned substrate and we investigated the electrochemical property of the device by Cyclic Voltammetry (CV) experiments comparing with that of a normal flat Au substrate. We think these nano-patterned Au substrates can be applied as potentially usable elements for the development of biosensor and other bioelectronic devices.