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Antioxidant properties of brown seaweed (Sargassum siliquastrum) extracts were evaluated using various antioxidant measurements, i.e., inhibitory effect on thiobarbituric acid-reactive substances (TBARS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating effect, reducing power effect, and total phenolic compounds. When the extraction solvents n-hexane, chloroform, ethanol, and water were compared, the water extract showed the highest yield in extracted mass. Total phenolic compounds were the highest in the ethanol extract, with 127.4 mg/g. The TBARS inhibition of chloroform and ethanol extracts at 10 mg/mL was 90.9% and 80.9%, respectively. DPPH radical scavenging capacity was more than 90% in all extracts at 1 mg/mL. The chloroform extract exhibited the highest metal ion chelating ability of 69.6% at 10 mg/mL. The reducing power was found to be the highest in the ethanol extract at 10 mg/mL, showing an effect similar to ascorbic acid. Thus, the ethanol extract of S. siliquastrum has potential as a natural antioxidant.

Three antifouling active compounds of L-pyroglutamic acid (PGA), triethyl citrate (TEC) and di-n-octylphthalate (DNOP) were isolated from the brown seaweed Ishige okamurae. Approximately 2.8 mg PGA, 1.7 mg TEC, and 2.0 mg DNOP were isolated from 600 g of I. okamurae powder. The concentrations of PGA, TEC, and DNOP required to cause foot repulsion in 50% of mussels (RD50) were 9, 26, and 0.08 mM, respectively. The PGA, TEC, and DNOP concentrations required to inhibit 50% attachment of algal spores (ID50) were 24, 50 and 0.1 mM, respectively. These compounds showed stable antifouling activities against mussel and algal spore attachment.

A study was made to investigate possible formation by the crustose coralline algaLithophyllum yessoenseof multiple allelopathic-related substances against the settlement and germination of spores of various seaweeds. Seven different solvents (n-hexane, diethyl ether, acetone, ethyl acetate, acetonitrile, methanol, distilled water) and seawater were used to obtain crude extracts and secretory exudates from the coralline alga. The extracts and the algal conditioned seawater were tested for inhibitory activity against the settlement and germination of spores from 17 species representing 15 genera. Spore settlement of 14 species was inhibited over 90% by one or more extracts of the six organic solvents and conditioned seawater. The germination of spores from 13 species was inhibited by one or more extracts of all seven solvents and conditioned seawater. The species where spore settlement was not significantly affected showed strong inhibition of germination, andvice versa.

Seaweed flora has been disappearing on rockyareas of the ocean. Meanwhile, crustose corallinealgae, which are non-articulated calcareous algae,are growing and covering these rock surfaces withpink- or white-colored crusts. This phenomenon isgenerally called algal whitening. It is now recog-nized as a natural hazard adversely affectingmarine ecosystems and damaging commercialfishing areas.

Occult metastases are a major cause of cancer mortality, even among patients undergoing curative resection. Therefore, practical strategies to target the growth and persistence of already established metastases would provide an important advance in cancer treatment. Here, we assessed the potential of protein therapy using a cell permeable NM23-H1 metastasis suppressor protein. Hydrophobic transduction domains developed from a screen of 1,500 signaling peptide sequences enhanced the uptake of the NM23 protein by cultured cells and systemic delivery to animal tissues. The cell-permeable (CP)-NM23 inhibited metastasis-associated phenotypes in tumor cell lines, blocked the establishment of lung metastases, and cleared already established pulmonary metastases, significantly prolonging the survival of tumor-bearing animals. Therefore, these results establish the potential use of cell-permeable metastasis suppressors as adjuvant therapy against disseminated cancers. Cancer Res; 71(23); 7216–25. ©2011 AACR.

We demonstrate the surface plasmon-enhanced blue light-emitting diodes (LEDs) using Ag nanoparticles embedded in p-GaN. A large increase in optical output power of 38% is achieved at an injection current of 20 mA due to an improved internal quantum efficiency of the LEDs. The enhancement of optical output power is dependent on the density of the Ag nanoparticles. This improvement can be attributed to an increase in the spontaneous emission rate through resonance coupling between the excitons in multiple quantum wells and localized surface plasmons in Ag nanoparticles embedded in p-GaN.

Silica gel chromatography HPLC, El-Mass, and NMR analyses were performed in order to determine the structure obtained from the separation and refinement of the main components of an ethanol extraction of Sargassum siliquastrum, which indicated its antioxidant activity An ethanol extraction of Sargassum siliquastrum demonstrated the strongest antioxidant activities of ethyl acetate when isolated by silica gel chromatography This amounts to 84.9 +/- 1.2% of its 0.5 mg ml(-1) concentration. The thiobarbituric acid reactive substances (TBARS) measurements from 3 isolations of an HPLC separation of ethyl acetate showed that the antioxidant activity of peak 2 was the most dominant at 84.08% in a 0.5 mg ml(-1) concentration. Peak 2 was verified as a type of chromene through El-Mass and NMR analysis. Its metal sealing characteristic was low while its characteristic of TBARS and DPPH erasure indicated similar or higher levels of metal sealing characteristic. The NMR spectroscopic data was used to elucidate the structure of this new compound, which showed strong antioxidant activity in the assay.

We report on the properties of green light-emitting diodes (LEDs) with a photonic crystal (PC) structure on p-GaN. A PC structure was fabricated by the selective area epitaxy of p-GaN using SiO2 nanopillars. The electrical characteristics of LEDs with PC were not degraded and the optical output power of green LEDs with PC was increased by 70% at 20 mA of injection current compared with that of conventional LEDs without PC. This enhancement of optical output power was attributed to the improvement in light extraction efficiency by the SiO2/p-GaN PC layer on p-GaN.