Effects of caffeine ingestion and thermotherapy on blood orexin circulation in humans

Food Science and Biotechnology - Caffeine and orexin can affect awakening, neuroendocrine, and sympathetic nerve function. Our previous study has reported that caffeine intake can increase human...     

Optimization of salts in medium for production of carboxymethylcellulase by a psychrophilic marine bacterium, <Emphasis Type="Italic">Psychrobacter aquimaris</Emphasis> LBH-10 using two statistical methods

The concentration of four mineral salts in the medium for the production of carboxymethylcellulase (CMCase) by Psychrobacter aquimaris LBH-10 were optimized using orthogonal array method (OAM) and response surface method (RSM) and their results from two statistical methods were compared. The analysis of variance (ANOVA) of data from central composite design (CCD) based on OAM indicated that potassium phosphate gave the highest percentage participation for cell growth as well as production of CMCase. However, their relative participations of four salts for cell growth were different from those for production of CMCase. The ANOVA of results from RSM indicated that highly significant factors (“probe>F” less than 0.0001) for cell growth were K₂HPO₄ and (NH₄)₂SO₄, whereas those for production of CMCase were K₂HPO₄, NaCl, and MgSO₄·7H₂O. The optimal concentration of K₂HPO₄, NaCl, MgSO₄·7H₂O, and (NH₄)₂SO₄ for cell growth extracted by Design Expert Software based on RSM were 7.10, 0.84, 0.24, and 0.33 g/L, respectively, whereas those for production of CMCase were 3.00, 0.52, 0.34, and 0.45 g/L. The optimal concentrations of salts for cell growth and production of CMCase using RSM basically coincided with those using OAM as well as those from ‘one-factor-at-a-time’ method. The production of CMCase by P. aquimaris LBH-10 with optimized concentrations of salts was 273.0 U/mL, which was enhanced by 1.27 times higher than the previous report.     

Water extract of licorice (Glycyrrhiza uralensis Fisch.) Supplementation is related with decreased lipid peroxidation among healthy male smokers with glutathione-S-transferase M1 positive genotype

Recently, licorice (Glycyrrhiza uralensis Fisch., GU) has demonstrated significant in vitro and in vivo antioxidant properties. In this study, it was tested that a daily regimen of supplementation with water extract of GU would ameliorate oxidative stress and whether effects were modulated by the glutathion-S-transferase (GST) polymorphisms. Forty healthy male smokers aged 20–60 were divided evenly into 2 groups and given either 260 mL of GU extracted with hot water or 260 mL of oligosaccharide based placebo every day for 8 weeks without any change of usual food intake, and blood samples were drawn before and after the intervention. Eight weeks of GU supplementation significantly decreased plasma conjugated dienes (a maker for lipid peroxidation) in GSTM1 positive subjects, but not in the GSTM1 null genotype group. Our finding suggests that consumption of licorice water extract might be effectively decreasing lipid peroxidation in the subgroup of smokers who have GSTM1 gene.     

Optimization of adhesive strength to plywood of gelatin processed from dorsal skin of yellowfin tuna (<Emphasis Type="Italic">Thunnus albacares</Emphasis>)

Gelatin from yellowfin tuna (Thunnus albacares) dorsal skin was optimized for adhesive strength to plywood using surface response methodology of a central composite design with a dependent variable of adhesive strength (Y, kg _f /cm²) and two independent variables of gelatin concentration (X₁, %) and hardening time (X₂, hrs). From the above design, a maximum adhesive strength of 49.84 kg _f /cm² was obtained under the optimal treatment condition of 15.85% gelatin concentration and 25.68 hr hardening time. The adhesive strength under optimum conditions was 50.93 kg _f /cm². The adhesive strength of the tuna gelatin was shown to be superior to that of bovine and porcine gelatins which had adhesive strengths of 34.75 and 34.9 kg _f /cm², respectively.     

High Performance β-Ga2O3 Schottky Barrier Transistors with Large Work Function TMD Gate of NbS2 and TaS2

Gallium trioxide, β-Ga₂O₃, has been recently studied due to its promising semiconducting properties as active material in transistors or Schottky diodes. Transistors with β-Ga₂O₃ channels are mostly metal oxide field effect transistors (MOSFET), and they show very negative threshold voltages (V_th) in general. Metal semiconductor field effect transistors (MESFETs) with top gate are also reported with less negative V_th. Still, β-Ga₂O₃ MESFETs are only a few. Here, bottom gate architecture β-Ga₂O₃ MESFETs using transition metal dichalcogenide (TMD) NbS₂ and TaS₂ are reported. Due to the large work functions of those metallic TMDs, the MESFETs display minimum subthreshold swing of 61 mV dec⁻¹, small V_th of −1.2 V, minimum OFF I_D of ≈100 fA, and maximum ON/OFF current ratio of ≈10⁸. Both β-Ga₂O₃ Schottky diodes with TaS₂ and NbS₂ display good junction stability even after 300 °C measurements in 10 mTorr vacuum. When the β-Ga₂O₃ MESFET with TaS₂ gate is integrated as a switching FET into an organic light emitting diode (OLED) circuit, it demonstrates long-term leakage endurance performance, maintaining an OLED brightness higher than 58% of the initial intensity after 100 s passes since the ON-switching point, which is even superior to the performance of conventional a-IGZO MOSFET switch.     

Synthesis of single-walled carbon nanotubes using hemoglobin-based iron catalyst

Hemoglobin (Hb) was used as a catalyst for the growth of single-walled carbon nanotubes (SWCNTs). Hb was deposited onto a hydrophilic treated substrate by spin coating method. After oxidation at 800 °C, protein chains were decomposed and iron oxide nanoparticles remained with an average diameter of 2.29 nm. High quality SWCNTs were synthesized with an average diameter of 1.22 nm. The protein chains prevent iron atoms aggregation and so the size of the nanoparticles is smaller than that from ferritin-like proteins.     

Antioxidant activities and anticancer effects of red yeast rice grown in the medium containing garlic

The effects of culture time on antioxidant and anticancer activities of red yeast rice-garlic (RYRG) ethanol extracts were investigated. RYRG is a product of red yeast rice (Monascus pilosus) grown in medium containing garlic for 0, 2, 4, 6, and 8 weeks. The total phenolic and total flavonoid contents of RYRG extracts were increasing with the length of culture periods. The DPPH free radical scavenging activity of RYRG extracts also increased with culture time. The RYRG extracts prevented brain lipid peroxidation in culture time dependent manner. The RYRG extracts showed anti-proliferative effects against HepG2 human liver cancer cells, HT-29 human colon cancer cells, and B16F10 murine melanoma cells. The IC₅₀ value of 8-week fermented RYRG extract was the lowest among sample groups. Therefore, the results indicated that RYRG extracts exhibit culture time-dependent antioxidant and anti-cancer activities associated with the increase on phenolic and flavonoid contents. The RYRG extract is therefore a promising candidate as chemopreventive agents.     

Antioxidant Activity of Hydrogen Water Mask Pack Composed of Gel-Type Emulsion and Hydrogen Generation Powder

In this study, hydrogen generation powder samples were prepared using zinc carbonate as a precursor, at a temperature varying from 400 to 700 °C in H₂ atmosphere, and were characterized in terms of antioxidant activity. The concentration of dissolved hydrogen obtained by the powder samples was measured using a dissolved hydrogen meter as a function of time. In addition, the antioxidant activity of the samples was evaluated based on the Oyaizu’s method, removal rate of ·OH radicals, and ferric reducing antioxidant power. Finally, the hydrogen mask pack was fabricated using the hydrogen generation powder sample and gel-type emulsion. In the clinical test on the mask pack, the effect of the mask on skin aging was characterized and compared to that of a commercial sample. The skin densities of the participants in the experimental group and the control group increased by 18.41% and 9.93% after 4 weeks, respectively. The improved skin density of the participants who used the hydrogen mask pack in the experimental group, might be attributed to the recovery effect of the hydrogen molecule in the mask pack on the denatured thick skin layer.