Calculating the Crystallite Size of Microsorum scolopendria AgCl Nanoparticles and Their Biological Activities

In this work, AgCl nanoparticles were synthesized from Microsorum scolopendria (MS) aqueous extract and AgNO3 solution. Preliminary confirmation was a color change from a light brown to a dark-colored solution and a UV-Vis spectra surface plasmon resonance peak at 427 nm. Measured vibrational frequencies at 1713 cm1 and 1030 cm1 for C-O stretching of carboxylic acid or aliphatic ketone, and 1547 cm1 for possibly N-O stretching of nitro compounds by Infrared (FTIR) analysis explain the possible biomaterial electronegative species or functional groups responsible for the reduction of Ag ( 1) to Ag (0) for the formation of MS-AgCl nanoparticles. XRD analysis studies revealed that these particles contained face-centered cubic crystallites of metallic AgCl of 100 % with an average calculated crystallite size range of 30.34 nm (SD = 5.10 nm) by Scherrers equation and a calculated crystallite size of 66.04 nm with a lattice strain of 0.00175 nm by Williamson Hall equation. The measured albumin denaturing activity of MS-AgCl nanoparticles gave an IC50 value of 26.70 g/mL and 1.35 g/mL for the positive control diclofenac. Additionally, the measured ability of phosphomolybdate complex formation, the antioxidant IC value of MS-AgCl nanoparticles was 35.29 g/mL, and positive control ascorbic acid was 13.91 g/mL. In all, using MS fern frond aqueous extracts, this preliminary work confirms MS-AgCl nanoparticles as potential therapeutic agents for oxidative stress, inflammatory problems, and related diseases.

Melatonin Enhances Object Recognition Memory through Melatonin MT1 and MT2 Receptor-Mediated and Non-Receptor-Mediated Mechanisms in Male Mice

Melatonin (MEL) has been reported to have acute enhancing effects on some aspects of cognition. Recently, we revealed that N1-acetyl-5-methoxyquinuramine (AMK), a brain metabolite of MEL, is much more potent than MEL in converting short-term memory (STM) to long-term memory (LTM) with a single administration immediately after the acquisition trial of the novel object recognition (NOR) task. These data suggest that the memory-enhancing effects of MEL may be mediated by mechanisms independent of the activation of MEL MT1 and MT2 receptors. In the present study, we examined the contribution of MT1 and MT2 receptor-mediated and non-receptor-mediated mechanisms to the acute memory-enhancing effects of MEL using NOR task. Mice were administered with either MEL, AMK, or a highly selective MT1/MT2 receptor agonist ramelteon (RAM) immediately after the acquisition trial and the effects of varying doses of these drugs on both STM and LTM performance were compared. We found that both AMK and RAM were more potent than MEL in both facilitating STM and promoting LTM formation. We also found that pretreatment with luzindole, a MT1/MT2 receptor antagonist, markedly suppressed only the effects of RAM. These results suggest that acutely administered MEL enhances NOR memory through both MT1 and MT2 receptor-mediated and non-receptor-mediated mechanisms.

Origin of enriched uranium contained in Japanese atmospheric deposits

The chemical compositions of atmospheric deposits collected in Fukuoka, Japan, in 1964 and 2000, which are known to have high 235U/238U uranium isotope ratio were determined. High uranium contents relative to that of continental crust were observed for the deposition samples in 1964 together with the high 235U/238U ratios, which indicated that the origin of uranium is fallout materials due to the large-scale 1961- 1962 nuclear explosions conducted by US and former USSR. The deposits in 2000 were mainly composed of dusts from the East Asia. This suggested that uranium with a high 235U/238U ratio in the deposits in 2000 has been transported as a component of mineral dust particles contaminated with nuclear debris from nuclear test sites from the East Asian deserts and arid regions by the prevailing wind.

Furans-Maleimides Diels-Alder Reactions in Protic Ionic Liquid

The authors have studied the Diels-Alder reactions between furan derivatives and maleimide derivatives in an ionic liquid and have found that higher reactivity can be obtained in a protic ionic liquid [Mim]Tf2N than in the conventional organic solvent. Furthermore, in the Diels-Alder reactions of 2- and 2,5-alkylfurans with N-alkylma- leimide, the reactivity increases by extending the alkyl chain length of N-alkylmaleimide. In addition, it was demon- strated that endo-selectivity increases when 2,5-disubstituted furans are used. These results will be explained by comparing the stability of the Diels-Alder adduct with that of the products obtained from the reactions of 2-substituted furans and 2,5-disubstituted furans.

A New Epi‑neoverrucosane‑type Diterpenoid from the Liverwort Pleurozia subinfata in Borneo

New bioactive 13-epi-neoverrucosane diterpenoid,5β-acetoxy-13-epi-neoverrucosanic acid(1)along with three known secondary metabolites,13-epi-neoverrucosan-5β-ol(2),chelodane(3)and(E)-β-farnesene(4)were isolated from the MeOH extract of east Malaysia’s liverwort Pleurozia subinfata.The chemical structure of new compound was elucidated by the analyses of its spectroscopic data(FTIR,NMR and HR-ESI-MS).These epi-neoverrucosane-type compounds seem to be notable chemosystematic markers for P.subinfata in Borneo.Compound 3 was widespread in marine sponges however this is the frst record for 3 to be found in liverwort.These metabolites were tested for their antifungal potentials against selected fungi from the marine environment.Compound 1 exhibited efective antifungal activity against Lagenidium thermophilum.

New acetogenin katsuurallene from Laurencia saitoi collected from Katsuura, Japan

We examined the chemical constitution of the red alga Laurencia saitoi Perestenko,collected from Katsuura,Boso Peninsula,Chiba Prefecture,Japan.This specimen produced a new polyhalogenated acetogenin,named katsuural-lene(1),which structure was determined by the spectral methods,along with known diterpene,deoxyparguerol(2)and triterpene,thyrsiferol(3).In this paper we describe the structural elucidation of katsuurallene together with some biological activities.

Electrochemical behavior of [UO_2Cl_4]^(2-) in 1-ethyl-3-methylimidazolium based ionic liquids

In order to examine the chemical form of uranyl species in l-ethyl-3-methylimidazolium （EMI） based ionic liquids, UV-visible absorption spectra of solutions prepared by dissolving [EMI]2[UO2CI4] into a mixture of EMICI and EMIBF4 （50：50 tool%） were measured. As a result, it was confirmed that uranyl species in the mixture of EMICI and EMIBF4 existed as [UO2C14]2-. Cyclic voltammograms （CVs） of [UO2CI4]2- in the mixture were measured at 25 ~C using a Pt working electrode, a Pt wire counter electrode, and an Ag/Ag＋ reference electrode （0.01 M AgNO3, 0.1 M tetrabutylammonium perchlorate in acetonitrile） in a glove box under an Ar atmosphere. Peaks corresponding to one redox couple were observed around -1.05 V （Epc） and -0.92 V （Epa） vs. ferrocene/ferrocenium ion （Fc/Fc＋）. The potential differences between two peaks （AEp） increased from 101 to 152 mV with an increase in the scan rate from 50 to 300 mV s-1, while the （Epc ＋ Epa）/2 value was constant, -0.989 V vs. Fc/Fc＋ regardless of the scan rate. Furthermore, the diffusion coefficient of [UO2C14]2 and the standard rate constant were es- timated to be 3.7× 10^-8 cm^2 s 1 and （2.7-2,8） × 10^-4 cm s-! at 25 ℃. By using the diffusion coefficient and the standard rate constant, the simulation of CVs was performed based on the reaction, [UO2C14]2- ＋ e- = [UO2C14]3-. The simulated CVs were found to be consistent with the experimental ones. From these results, it is concluded that [UO2C14]2- in the mixture of EMIC1 and EMIBF4 is reduced to [UO2C14]3- quasi-reversibly at -0.989 V vs. Fc/Fc＋.

Structural effect of fluorophore on phenylboronic acid fluorophore/cyclodextrin complex for selective glucose recognition

Based on the design of the fluorescent site of a fluorescent probe,we have created a unique system that changes its twisting response to sugar.Two probes were synthesized,in which phenylboronic acid and two kinds of aromatic fluorescent site(pyrene or anthracene)were conjugated by an amide bond.In the fluorescence measurement of pyrene-type probe 1,dimer fluorescence was observed at high pH.In induced circular dichroism(ICD)experiments,a response was observed only in the presence of glucose and γ-cyclodextrin,and no response was seen with fructose.On the other hand,in the fluorescence measurement of anthracene-type probe 2,dimer fluorescence was observed in the presence of both glucose and galactose,and the fluorescence was different from the case of fructose.When the ICD spectra of these inclusion complexes were measured,an inversion of the Cotton effect,which indicates a change in the twisted structure,was observed in galactose and glucose.These differences in response to monosaccharides may originate in the interaction between the fluorescent site and the cyclodextrin cavity.