Photoresponsive Porphyrin Nanotubes of Meso-tetra(4-Sulfonatophenyl)Porphyrin and Sn(IV) meso-tetra(4-pyridyl)porphyrin

Porphyrin macrocycles and their supramolecular nanoassemblies are being widely explored in energy harvesting, sensor development, catalysis, and medicine because of a good tunability of their light-induced charge separation and electron/energy transfer properties. In the present work, we prepared and studied photoresponsive porphyrin nanotubes formed by the self-assembly of meso-tetrakis(4-sulfonatophenyl)porphyrin and Sn(IV) meso-tetra(4-pyridyl)porphyrin. Scanning electron microscopy and transmission electron microscopy showed that these tubular nanostructures were hollow with open ends and their length was 0.4–0.8 μm, the inner diameter was 7–15 nm, and the outer diameter was 30–70 nm. Porphyrin tectons, H4TPPS42- : Sn(IV)TPyP4+, self-assemble into the nanotubes in a ratio of 2:1, respectively, as determined by the elemental analysis. The photoconductivity of the porphyrin nanotubes was determined to be as high as 3.1 × 10−4 S m−1, and the dependence of the photoconductance on distance and temperature was investigated. Excitation of the Q-band region with a Q-band of SnTPyP4+ (550–552 nm) and the band at 714 nm, which is associated with J-aggregation, was responsible for about 34 % of the photoconductive activity of the H4TPPS42--Sn(IV)TPyP4+ porphyrin nanotubes. The sensor properties of the H4TPPS42-- Sn(IV)TPyP4+ nanotubes in the presence of iodine vapor and salicylate anions down to millimolar range were examined in a chemiresistor sensing mode. We have shown that the porphyrin nanotubes advantageously combine the characteristics of a sensor and a transducer, thus demonstrating their great potential as efficient functional layers for sensing devices and biomimetic nanoarchitectures

Complex processing of lipids from liver of the gonatid squid <i>Berryteuthis magister </i>

Berryteuthis magister is one of the most common commercial species in the North-West Pacific, but its liver never was utilized before, though it was a rich source of the lipids with simple ether links, 1- О -alkyl-glycerol ethers (АGE), and ω3 polyunsaturated fatty acids (ω3 PUFA). Technology for complex processing of lipids from its liver is developed and presented in details. These forms of lipids are distinguished by a wide range of biologic activity: AGE are effective immunomodulators which enhance hemopoiesis, relieve lesions and lower risk of secondary lesions under radio-therapy and can be used for treatment of some malignant tumors (glioma, prostate cancer, lung carcinoma, etc.); ω3 PUFA could be used for prophylactic of cardiovascular diseases, Alzheimer’s sclerosis, senile dementia, skin diseases (protein synthesis control) and other diseases. The presented technology provides extraction of three preparations with different chemical composition and pharmacological activity. Both saturated and unsaturated AGE could be extracted using the property of different solubility in organic solvents for different components of the mixture of hydrolyzed lipids. The main component of the saturated AGE fraction is chimyl alcohol (90.5 %), but the unsaturated fraction contains 54.7 % of monounsaturated AGE. The ω3 PUFA are concentrated to summary 46 % content of eicosapentaenoic acid and docosahexaenoic acid by the method of fatty acids crystallization with carbamide. Comparing with traditional raw materials for АGE and ω3 PUFA production, as shark liver, the liver of gonatid squid is more suitable because of its high and accessible resources, whereas sharks are presented in bycatch only so cannot be considered as a stable source

Alkyl Glycerol Ethers as Adaptogens

Τhis mini-review summarizes the hematopoietic and immunostimulating properties of alkyl glycerol ethers (AGs) reported earlier in the literature available to us. The role of AGs in the nervous system and aging of the body are also briefly described. We made an attempt to consider the data in terms of adaptation. The hematopoietic, immunostimulating and antioxidant properties of AGs in a variety of experimental situations, including stress, as well as the protective action of AGs against some adaptation diseases, allow us to consider them as substances that prevent some negative effects of stress and promote adaptation. The new approach to AGs as adaptogens seems promising and opens good opportunities for their new application

The Phospholipid Molecular Species Profile of Apostichopus japonicus Tissues Modifies through Exposure to n-3 Polyunsaturated Fatty Acid-Deficient Diet

The sea cucumber Apostichopus japonicus, being a target species of commercial fisheries and aquaculture, is also used as a source of biologically active compounds with high pharmacological potential. By the methods of high-performance liquid chromatography with high resolution mass spectrometry, we analyzed the major structural phospholipids (PL)&mdash;glycerophosphoethanolamines (PE), glycerophosphocholines (PC), glycerophosphoserines (PS), and glycerophosphoinositols (PI)&mdash;in tissues of wild and cultured sea cucumbers. The intestines of the wild and cultured animals differed from the other tissues by an elevated content of molecular species of PE, PC, and PS with 22:6n-3 fatty acid. The respiratory trees of the studied animals contained a high level of odd-chain PI and PI with 20:4n-6. The exposure to n-3 PUFA-deficient diet resulted in substantial changes in the molecular species profile of PL of the wild and cultured animals. The cultured sea cucumbers showed a significant decrease in the 20:5n-3 content in all four studied PL classes. A replacement of 20:5n-3 by 20:4n-6 occurred in PE, PC, and PI. The decrease in the level of molecular species of PS with 20:5n-3 was compensated by an increase in the level of monounsaturated long-chain PS. The diet of cultured sea cucumbers is a crucial factor for enhancing the nutritional properties of the product obtained from them

Self-assembly and photoconductivity of binary porphyrin nanostructures of meso-tetrakis(4-sulfonatophenyl)porphine and Co(III) meso-tetra(4-pyridyl)porphine chloride

The tunable characteristics of the porphyrin molecular tectons have given rise to interest in investigating the self-assembled porphyrin nanoarchitectures for designing new materials. Nanostructures created by the self-assembly of meso-tetrakis(4-sulfonatophenyl)porphine and Co(III) meso-tetra(4-pyridyl)porphine chloride and their photoconductivity are reported here. These nanostructures were characterized by electron microscopy. The ratio of porphyrin tectons in the binary porphyrin nanostructures is about 3:2. The nanostructures demonstrate a high photoconductivity of about 5 × 10−5 S m−1. The dependence of the photoconductivity of the porphyrin nanostructures on the path length and temperature is demonstrated

MORPHOLOGICAL PROPERTIES ANDPHOTOCONDUCTIVITY OF SELF-ASSEMBLED Sn/CoPORPHYRIN NANOSTRUCTURES.

In this study the synthesis and characterization of meso-substituted Sn and Co porphyrinnanostructures were carried out. The effect of pH of medium on the formation of Sn/Coporphyrinnanostructures was studied. The formation process is caused by the net charge on theporphyrin, which is controlled by protonation/deprotonation of the oppositely charged periphery.Thischarge determines also stoichiometric ratios of porphyrins in the nanostructures. It was foundthat the contact of the donor (Co-porphyrin) with acceptor (Sn-porphyrin) provides photoconductivityof nanostructures under illumination with visible light. It was shown that the increase oftemperature decreases their conductance both in the dark and under illumination

Protective Properties of Marine Alkyl Glycerol Ethers in Chronic Stress

In this paper we discuss the effect of alkyl glycerol ethers (AGs) from the squid Berryteuthis magister on a chronic stress model in rats. The study was performed on 32 male Wistar rats. Animals received AGs at a dose of 200 mg/kg through a gavage for six weeks (1.5 months), and were divided into four groups: group 1 (control), group 2 (animals received AGs), group 3 (stress control), group 4 (animals received AGs and were subjected to stress). Chronic immobilization stress was induced by placing each rat into an individual plexiglass cages for 2 h daily for 15 days. The serum lipid spectrum was evaluated by the content of total cholesterol, triglycerides, high-density lipoprotein cholesterol, low lipoprotein cholesterol and very low-density lipoprotein cholesterol. The atherogenic coefficient was calculated. The hematological parameters of peripheral blood were evaluated. The neutrophil–lymphocyte ratio was counted. The levels of cortisol and testosterone in blood plasma were determined. AGs at the selected dose did not have a significant effect on the body weight of rats in the preliminary period of the experiment. Under stress, the body weight gain, the concentrations of very low-density lipoprotein cholesterol and blood triglycerides decreased significantly. The neutrophil–lymphocyte ratio in animals treated with AGs shifted towards lymphocytes. A favorable increase in the percentage of lymphocytes was found in the stressed group of animals treated with AGs. So, for the first time, it was found that AGs prevent stress-induced suppression of the immune system. This confirms the benefit of AGs for the immune system under chronic stress. Our results prove the efficiency of the use of AGs for treating chronic stress, a serious social problem in modern society

Direct electrochemistry of cyt c and hydrogen peroxide biosensing on oleylamine- and citrate-stabilized gold nanostructures

Two types of gold nanostructures are discussed: charge(citrate)-stabilized and sterically(OA)-stabilized gold nanostructures and their assembly with heme-containing metalloproteins, cyt c and horseradish peroxidase (HRP) enzyme into a bioelectrochemically active nanoarchitecture as well as a sensor application. The assembly of the nanostructures on the thin-film gold electrodes and the immobilization and electrochemical properties of metalloproteins on these electrodes are presented. The nanostructured bioelectrochemical interfaces provide a good environment for the stable and reproducible immobilization of electroactive proteins. We show that both molecules preserve their functionalities (electrochemical and biocatalytic activities). The amount of electroactive proteins immobilized on the nanostructured electrode surfaces is significantly increased compared to the flat electrode surfaces. The kinetic parameters of the heterogeneous direct electron transfer reaction of cyt c on the nanostructured electrodes are compared. The thin-film gold electrodes modified with OANWs, OANPs, and citrate-stabilized NPs and covalently immobilized HRP exhibit an excellent catalytic activity toward the oxidation of hydrogen peroxide with a working concentration range from 20 μM to 500 μM, a sensitivity of 0.031 A M−1 cm−2 (RSD 0.005), 0.027 A M−1 cm−2 (RSD 0.004), and 0.022 A M−1 cm−2 (RSD 0.0035), and a detection limit of 5 μM, 8 μM, and 14 μM, respectively (RSDs near the detection limits were 9–12%). The HRP sensor characteristics are improved significantly compared to the flat thin-film sensors by using gold nanostructures. Our study shows that ultrathin gold nanowires and nanoparticles with two different types of stabilizing agents are promising materials for assembling biomolecules into functional nanoarchitectures for metalloprotein-based bioelectrochemical sensors

Synaptamide Modulates Astroglial Activity in Mild Traumatic Brain Injury

At present, the study of the neurotropic activity of polyunsaturated fatty acid ethanolamides (N-acylethanolamines) is becoming increasingly important. N-docosahexaenoylethanolamine (synaptamide, DHEA) is a highly active metabolite of docosahexaenoic acid (DHA) with neuroprotective, synaptogenic, neuritogenic, and anti-inflammatory properties in the nervous system. Synaptamide tested in the present study was obtained using a chemical modification of DHA isolated from squid Berryteuthis magister liver. The results of this study demonstrate the effects of synaptamide on the astroglial response to injury in the acute (1 day) and chronic (7 days) phases of mild traumatic brain injury (mTBI) development. HPLC-MS study revealed several times increase of synaptamide concentration in the cerebral cortex and serum of experimental animals after subcutaneous administration (10 mg/kg/day). Using immunohistochemistry, it was shown that synaptamide regulates the activation of GFAP- and S100&beta;-positive astroglia, reduce nNOS-positive immunostaining, and stimulates the secretion of neurotrophin BDNF. Dynamics of superoxide dismutase production in synaptamide treatment confirm the antioxidant efficacy of the test compound. We found a decrease in TBI biomarkers such as GFAP, S100&beta;, and IL-6 in the blood serum of synaptamide-treated experimental animals using Western blot analysis. The results indicate the high therapeutic potential of synaptamide in reducing the severity of the brain damage consequences

Oleylamine-Stabilized Gold Nanostructures for Bioelectronic Assembly. Direct Electrochemistry of Cytochrome c

Methods to prepare ultrathin gold nanowires and monodisperse nanoparticles based on the intrinsic property of gold(I) ions to form aurophilic interactions stabilized by oleylamine and long-chain alkylamine have been widely explored. Due to the low thermodynamic stability of the high aspect ratio nanostructures, their conjugation and assembly into functional nanosystems have not been explored so far. One of the reasons for this is that the surface of the nanostructures is insulated by stabilization compounds, which preserve the integrity of the nanostructures but at the same time form an insulating barrier in electronic and electrochemical systems in contact areas and for the charge transfer reactions. Conjugation of a metalloprotein cytochrome c (Cyt c) with oleylamine-stabilized gold ultrathin nanowires and nanoparticles into a bioelectrochemically active nanoarchitecture is presented here for the first time. Methods of preparing and assembling the ultrathin nanowires and nanoparticles on the thin-film gold electrodes are shown. Thermodynamic and kinetic parameters were obtained for the direct electron transfer reaction of cyt c on these surfaces. Nanowires are responsible for an approximately −20 mV shift in the redox potential of the ferri/ferro-cyt c couple relative to a thin-film gold electrode