Characterization of Capsaicin-Loaded Nanoemulsions Stabilized with Alginate and Chitosan by Self-assembly

The objectives of this research were to characterize capsaicin-loaded nanoemulsions stabilized with natural biopolymer such as alginate and chitosan for use as a functional ingredient delivery system. The biopolymer nanoemulsion was prepared using self-assembly emulsification methods, and the capsaicin included oleoresin capsicum as the core material in the nanoemulsion. The particle sizes of the double-layer nanoemulsions prepared with alginate (AN) and chitosan (CN) were 20 nm or lower. The triple-layer nanoemulsion, which was prepared by complexation with chitosan and alginate (CAN), was successfully prepared with particle sizes on the nanoscale through the electrostatic interactions between the carboxylic groups and amine groups of the biopolymers. The Zeta potential value, which is an indicator of the overall stability and physicochemical properties of the nanoemulsion, of AN and CN were significantly higher than SN and CAN (p < 0.01). In conclusion, the double-layer nanoemulsions incorporated with alginate and chitosan can be expected to improve the stability of nanoemulsion. In addition, this system holds promise for use in the production of functional foods containing functional ingredients.     

Design and fabrication of diffusive solar cell window

A diffusive solar cell window was designed and fabricated with uniformly distributed nanocomposite particles in a light diffusive plate that was sandwiched between two glass layers. The entire composite construction transfers light radiation to solar cells at the edge of the windows. It is based on a new combination of existing technologies because of it uses mature, mass-produced components - solar cells - as well as nanocomposite particles that are embedded inside the light-guide plate. They are integrated using an inexpensive and widely used method for making building windows. The result is an inexpensive, strong, stable, view quality-preserving solar energy-harvesting window that has no close competition. The diffusive solar cell window does not suffer from aging, and products that are made using diffusive solar cell window technology will be new entries to the solar power generation window market.     

Enzyme-derived deer velvet extract activate the immune response in cyclophosphamide-induced immunosuppressive mice

Deer velvet (DV) is an oriental traditional medicine used to treat various diseases. The present study examined the effect of flavourzyme-derived DV extract (YC-1101) on macrophages and an immunosuppressed mouse model. YC-1101 induced activation of macrophages as measured by nitric oxide production, cell proliferation, and cytokine release via concentration-dependent phosphorylation of c-Jun N-terminal kinase, extracellular signal-regulated kinase, and AKT, and nuclear translocation of p65 in macrophages. In addition, oral YC-1101 administration significantly increased splenocyte proliferation and natural killer cell activity in the immunosuppressed mouse model. Moreover, the levels of immune-related cytokines such as tumor necrotic factor-α, interferon-γ, and interleukin-2 were significantly increased by YC-1101 treatment comparable to the control group. Thus, these results suggest that YC-1101 is an efficient natural ingredient that has an immune-enhancing effect, and it might be a potential functional food for improving immunity.

     

Potential of a lactic acid bacterial starter culture with gamma-aminobutyric acid (GABA) activity for production of fermented sausage

The ability of lactic acid bacterial starter cultures to produce gamma-aminobutyric acid (GABA) during sausage fermentation was studied. Among 305 strains of lactic acid bacteria isolated from kimchi samples, 11 strains were selected as starter candidates based on the following criteria: growth speed, pH lowering ability, and biogenic amine productivity including GABA-producing activity. During in vitro tests, the Y8 (Lactobacillus brevis), O52, and KA20 strains produced 39.00 ± 1.36, 49.73 ± 3.80, and 64.59 ± 0.61 mg/kg of GABA, respectively. Interestingly, although isolate Y8 showed low productivity in vitro, the GABA content it produced during in situ tests (61.30 ± 2.61 mg/kg) was similar to that produced by isolate PM3 (L. brevis) used as positive control (69.64 ± 2.20 mg/kg). Therefore, isolate Y8 was selected as the best functional starter culture for the production of fermented sausage because it exhibited rapid growth, safety, and abundant GABA productivity.     

Survival and growth of B. cereus group and presumptive Cronobacter spp. contaminated naturally in rehydrated sunsik

Survival and growth of Bacillus cereus group and presumptive Cronobacter in the rehydrated sunsik were investigated to control the pathogens. Five sunsik contaminated naturally by the pathogens were rehydrated with hot waters of 50, 60, 65, and 70°C and kept for 24 hr at 5 and 25°C. Survival and growth of B. cereus seemed to be influenced not by rehydration water temperature, but by storage temperature and time after rehydration. However, survival and growth of Cronobacter was influenced by both rehydration temperature and storage conditions. Especially, storage temperature and time seemed to be more important than the rehydration temperature to limit the growth of Cronobacter. Therefore, it is required to take immediately the sunsik after rehydration with at least 65°C water, otherwise within 6 hr at room temperature for the risk reduction of B. cereus and Cronobacter.     

Effect of the precutting process on sanitizing treatments for reducing pathogens in vegetables

Food Science and Biotechnology - The effectiveness of sanitizing treatments was investigated on reducing pathogens inoculated in whole or cut fresh vegetables, including Brussels sprouts, carrots,...     

Abstracts: Comparison of hydration,tyrosinase resistance,and antioxidant activation in three kinds of pearl powders

pp. 133–145 In recent years, people have bred freshwater pearls as a substitute for natural pearls that occur in seawater, and they have also developed water‐soluble pearl powder (P‐w) and ultra‐micro (P‐μ) and ultra‐nano pearl powder (P‐n) products. However, neither the scientific value of pearl powder, nor the differences in efficiencies of different pearl powder products is still unknown. In this study, the effectiveness of three kinds of pearl powder products in various applications was compared. Tests for transepidermal water loss (TEWL) and evaluations of the skin surface hydration of test subjects showed that pearl powder has a satisfactory moisturizing effect on skin and that P‐μ has a distinctly stronger moisturizing effect than P‐w. The three pearl powder products can also significantly reduce the activation of tyrosinase and free radicals. In tests for reducing power and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) for scavenging free radicals, P‐n and P‐μ showed better performance than P‐w. These results provide a reliable scientific basis for the use of pearl powder in beauty treatment, resistance to aging, and clinical medical treatment.     

Enhanced stability of crude protease from kiwifruit (Actinidia deliciosa) by adding hydrocolloid for organic processed food uses

Crude protease originating from kiwifruit (Actinidia deliciosa) was extracted for organic processed food uses. The protease included in the kiwifruit can be utilized for organic uses instead of current commercial enzymes from microbial origin, which are not suitable for organic processed food. Crude protease extracted by physical treatment rather than any biochemical purification methods was appropriate for the organic processed food uses. However, crude protease extract has been found to be unstable for processing and storage usage, which has to be modified to be stable by appropriate methods suitable for organic processed food uses. The proteolytic activity of the protease extracted from kiwifruit was measured using casein as a substrate. The decreased inactivation rate constant of crude protease treated with guar gum and locust bean gum within the temperature range of 30–50°C implied the enhanced stability of crude enzymes by treatment with hydrocolloid. The half-times of crude proteases treated with guar gum and locust bean gum were higher than the half-time of native crude protease at 40°C (optimum temperature of the native crude protease), with values of 55.45 min for the guar gum-treated sample, 50.23 min for the locust bean gum-treated sample and 23.26 min for the native sample, demonstrating the quantitative evidence of the enzyme stability. The relatively stable maintenance of the proteolytic activity has helped to realize hydrocolloid-treated enzyme to be used for hydrolytic function in organic processed food applications.     

First principles computational studies of spontaneous reduction reaction of Eu(III) in eutectic LiCl‐KCl molten salt

Using first principles calculations, we study fundamental mechanism of spontaneous reduction reaction of Eu³⁺ to Eu²⁺ in eutectic LiCl‐KCl molten salt. We decouple the reaction Gibbs free energy into enthalpy and entropy contributions by using rigorous thermodynamic formalism. Key structural features of the solvation shell are characterized by the radial distribution function and the coordination number. Compared with Eu²⁺, the Eu³⁺ ion has a more rigid framework of the solvation shells, corroborating its stronger electrostatic interaction with neighboring ligands of Cl^? ions and a more favorable state on the aspect of enthalpy. Computations on vibrational frequency, however, pose significant contribution of vibrational entropy to the reaction Gibbs free energy for the reduction. Vibration frequency of Eu²⁺ is smaller than that of Eu³⁺, driving a more positive change of the entropy in the reduction reaction. Furthermore, an Eu²⁺ diffuses more quickly than an Eu³⁺ in the LiCl‐KCl molten salt with switching mechanism of ligand Cl^? ions in the solvation shell. Our results propose that the spontaneity of the reduction reaction is driven by the entropic contribution by overcoming the penalty of the reaction enthalpy.