Phellinus gilvus(PG) is a medicinal mushroom belonging to the Hymenochaetaceae basidiomycetes, and has advantages over many Phellinus species due to its short growth period (3 mo), making it cheaper to produce. In the current investigation, we determined the major components of the ethyl acetate extract of PG responsible for its biological activities and further compared the magnitude of the antioxidant/anti-inflammatory activities of components with the various fractional extracts of PG. As the results, the average total DPPH radical scavenging activities of both Fd and Fc of PG was 10 mg/mL, > 95%. Among the fractional extracts of PG, Fd had the greatest inhibitory activity with an IC50 value of 36.70㎍/mL, whereas Fb showed the lowest activity. PCA had even greater activity of NO inhibition than Fd with an IC50 value of 19.46㎍/mL. The mRNA expression of iNOS or COX-2 was nearly undetectable in the absence of LPS. However, LPS- stimulation markedly increased the expression of both iNOS and COX-2 genes. Fd inhibited the effect of LPS in a concentration-dependent manner. Six major compounds were identified from the ethyl acetate extract of PG, and protocatechualdehyde (PCA) was supposed to be the major phenolic compound of PG responsible for its DPPH free radical scavenging activity and its inhibitory effects on LPS-induced NO production in RAW264.7 cells. Further in vitro and in vivo experiments are currently underway to confirm this observation and to investigate the detailed molecular mechanisms involved in the process as well as the biological activities of other fractions of Fd.
Laccase (Lcc; EC 1.10.3.2) belongs to a group of polyphenol oxidases, which catalyzed the oxidation of single-electron from phenolic substrates or aromatic amines. Many organisms possess several lcc encoding genes, and their biological functions diverge into many branches. There are many studies on biochemical function of Lccs, however, there are few studies about biological functions of one Lcc in detail. We researched on biological function of Lcc1, which is most abundantly secreted enzyme from vegetative mycelia into liquid culture in L. edodes. In our previous study, lcc1 gene was down regulated by RNAi method in L. edodes, and then ivrL1#32 was selected as a completely lcc1 dowaregulated transformant. We revealed that fruiting body development in ivrL1#32 was significantly suppressed compared to wild type strain. In this study, we observed the hyphal morphology of ivrL1#32. IvrL1#32 did not form thick aerial mycelium mat when grown on MYPG agar plate. From the observation using scanning electron microscope (SEM), hyphae of ivrL1#32 had many abnormal short branches and their mycelial density was lower than that of wild type strain. From transmission electron microscope observation (TEM), ivrL1#32 lacked obviously distinguishable outer and inner layer in their cell wall. In addition, the fibrous layer of ivrL1#32, which connected hyphae, obviously decreased. These morphological phenotypes would be caused by the absence of Lcc1 in L. edodes. Our results provide a clue to resolve of the biological function of Lcc1 in L. edodes.
Singapore will soon submit a national report to and subsequently appear before the UN Human Rights Council for a universal periodic review of its human rights laws and practices. This review will elicit a rare and unprecedented expression of whether and how Singapore feels it has adhered to international human rights law, and ways in which it may further refine or calibrate its domestic practices. This article seeks to identify Singapore’s human rights achievements; highlight challenges it should be prepared to address; and recommend measures it should adopt to promote human rights.
Magnetars are neutron stars possessing a magnetic field of about 1014-1015 G at the surface. Thermodynamic properties of neutron star matter, approximated by pure neutron matter, are considered at finite temperature in strong magnetic fields up to 1018 G which could be relevant for the inner regions of magnetars. In the model with the Skyrme effective interaction, it is shown that a thermodynamically stable branch of solutions for the spin polarization parameter corresponds to the case when the majority of neutron spins are oriented opposite to the direction of the magnetic field (i.e. negative spin polarization). Moreover, starting from some threshold density, the self-consistent equations have also two other branches of solutions, corresponding to positive spin polarization. The influence of finite temperatures on spin polarization remains moderate in the Skyrme model up to temperatures relevant for protoneutron stars. In particular, the scenario with the metastable state characterized by positive spin polarization, considered at zero temperature in Phys. Rev. C 80, 065801 (2009), is preserved at finite temperatures as well. It is shown that, above certain density, the entropy for various branches of spin polarization in neutron matter with the Skyrme interaction in a strong magnetic field shows the unusual behavior, being larger than that of the nonpolarized state. By providing the corresponding low-temperature analysis, we prove that this unexpected behavior should be related to the dependence of the entropy of a spin polarized state on the effective masses of neutrons with spin up and spin down, and to a certain constraint on them which is violated in the respective density range.