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The aim of this study is to demonstrate the effects of Ananas comosus L. leaves on diabetic-dyslipidemic rats. Hypoglycemic and hypolipidemic activities of the ethanolic extract of Ananas comosus L. leaves (EEACL) were evaluated in normal and alloxan-induced diabetic rats by oral glucose tolerance test and an olive oil load test. Anti-diabetic, anti-hyperlipidemic and anti-oxidative activities of EEACL were also investigated in diabetic-dyslipidemic rats induced by alloxan and a high-fat/high-cholesterol diet. EEACL at the dose of 0.40 g/kg significantly inhibited the increase in blood glucose in diabetic rats in oral glucose tolerance test, but did not cause any hypoglycerimic activity in normal rats. It also significantly inhibited the increase in postprandial triglycerides (TG) levels in both normal and diabetic rats in olive oil load test. After 15 days of treatment of diabetic dyslipidemic rats, EEACL significantly decreased blood glucose (-51.0%, P<0.01), TG (-50.1%, P<0.01), TC (-23.3%, P<0.01), LDL-c (-47.9%, P<0.01) and glycated albumin (-25.4%, P<0.01) levels, significantly increased serum high-density lipoprotein cholesterol levels (66.2%, P<0.01) and prevented lower body weight of diabetes (11.8%, P<0.05), significantly lowered lipid peroxidation productions of blood (-27.8%, P<0.01), brain (-31.6%, P<0.05), liver (-44.5%, P<0.01) and kidneys (-72.2%, P<0.05) compared with those in untreated diabetic dyslipidemic rats. These data suggest that EEACL has anti-diabetic, anti-dyslipidemic and anti-oxidative activities, which may be developed into a new plant medicine for treatment of diabetes and its complications.

Plants from the genus Sanguisorba have been treated as medicinal ingredients for over 2000 years. This paper reviews advances in the botanical, phytochemical and pharmacological studies of the genus. To date, more than 120 chemical constituents have been isolated and identified from these plants, especially from S. officinalis and S. minor. Among these compounds, triterpenoids, phenols and flavonoids are the primary biologically active constituents. Triterpenoids can be used as quality control markers to determine the quality of medicinal materials and their preparations. In vivo and in vitro studies have shown that plants from the genus Sanguisorba exhibit a wide range of pharmacological properties, including hemostatic, antibacterial, antitumor, neuroprotective and hypoglycemic activities. In Chinese medical practice, many drugs (e.g., tablets and powders) that contain S. officinalis roots have been used to treat leukopenia, hemorrhaging and burns. However, there is still a multitude of Sanguisorba species that have garnered little or no attention. Indeed, there are few reports concerning the clinical use and toxic effects of these plants. Further attention should be focused on the study of these species in order to gather information on their respective toxicology data, any relevant quality-control measures, and the clinical value of the crude extracts, active compounds, and bioactive metabolites from Genus Sanguisorba.

Vertically oriented multiple-walled carbon nanotubes (MWCNTs) aligned on a silicon substrate were covalently bonded with horseradish peroxidase (HRP) and used as biosensors or electrodes. The modified platform was investigated with Scanning Electron Microscopy (SEM), UV-Vis spectrophotometer and Cyclic Voltammetry (CV). The enzyme catalyzed reaction and the subsequent reduction of the enzymatic products by the platform were carefully investigated. The assay was done by measuring the absorbance of the dye formed from the reaction product of the substrates (phenol) and 4-aminoantipyrine. From the linear response, phenol can be quantitized in the range from 47 ppm to 750 ppm with a detection limit of 19 ppm (based on S/N = 3). The resulting modified aligned MWCNTs still exhibited enzymatic activities after storage of 13 days. The activity of the attached HRP was also demonstrated electrochemically.

This article reviews our recent work in constructing discrete multiporphyrin assemblies and supramolecular arrays through the application of two organising principles - crown ethers and tin(IV)porphyrin phenolates. The role of the crown ethers is illustrated by two examples: (a) the cation-induced control of the reduction potentials within a model 18C6 bearing naphthalene and naphthoquinone chromophores antipodally displaced on the crown ether in the presence of alkali metal cations and (b) in the complexation of dialkylammonium salt within the cavity of a 24C8 bischlorin system. Tin(IV)porphyrin phenolates provide a means of efficiently constructing multiporphyrin assemblies without the use of covalent bond formation. Their potential is illustrated through the formation of discrete trimers, using a “one pot” self-assembly strategy, as well as the generation of supramolecular arrays with sieve like networks.

Alcohols and phenols are tetrahydropyranylated in the presence of N,N',N″,N‴-tetramethyltetra-2,3-pyridinoporphyrazinato copper(II) in good to excellent yields under solvent-free conditions.

The reactions of dodecahydro-closo-dodecaborate oxonium derivatives with various phenols resulted in phenoxy-undecahydro-closo-dodecaborates in high yields. Using this method, a phthalocyanine zinc(II) complex containing four (B₁₂H₁₂)^2- species was prepared in high yield. The compound shows good photocatalytic activity. The combination of boron cages and phthalocyanines makes this compound useful for boron neutron capture therapy for cancer and photodynamic tumor therapy.

Three different metalated tetrapyrrolic macrocycles have been transferred by Langmuir-Blodgett technique directly onto piezoelectric quartz crystal covered with gold electrodes of a commercial quartz crystal microbalance instrument in order to perform a flow injection analysis. All floating films at the air-water interface have been analyzed by registration of Langmuir curves and by UV-vis reflection spectroscopy and brewster angle microscopy. The sensing performances of the modified gold electrodes were investigated by monitoring the frequency variation induced by the presence of several toxic phenols. The explored concentrations ranged around 10^-3 M and the corresponding frequency variations ranged between 10 and 200 Hz. All responses observed were fast, reproducible and reversible; moreover, the active layers are stable over long periods of utilization. The observation that interferences from fulvic acid are absolutely negligible is also noteworthy. The responses are not selective for each singular phenol derivative; notwithstanding this, to the best of our knowledge, this contribution represents one of the first examples of sensing layers for the monitoring of the total content of phenols.

Thin films of pure tetrakis-(isopropoxy-carbonyl)-copper-phthalocyanine (TIPCuPc), a novel functionalized phthalocyanine, and its hybrid junctions with colloidal rod-like TiO₂ nanocrystals (NCs) were deposited in order to elucidate their properties and application in piezoelectric chemical sensors. The strong tendency of the phthalocyanine to assembly was confirmed at the air/water interface by advanced Brewster Angle Microscopy (BAM) and UV-vis reflection spectroscopy techniques. In particular, H-type aggregates, in situ and at the air/water interface, self-associate in aligned 3D bulky domains. The characteristics of the molecule and of the assemblies were studied in the solid state by means of UV-vis spectroscopy, Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy and Atomic Force Microscopy (AFM). These studies prompted investigation of the operating conditions to process the bare TIPCuPc and related TiO₂ NC-based hybrid junctions as sensing active layers for phenol pollutants integrated in a Quartz Crystal Microbalance (QCM). Interestingly, the preferentially oriented phthalocyanine LB-film undergoes chemical interactions with the NC film, which enhances the sensitivity of the QCM sensor.

The cetyltrimethyl ammonium bromide (CTAB)-modified montmorillonite (MMT) was synthesized via a novel “dissolution and reassembly” method. To determine the optimal formula, the adsorption of C.I. Reactive Red 2 (X3B) with CTAB/MMT was investigated. The optimal CTAB/MMT nanocomposite was used to remove 2,6-dichlorophenol and p-nitrophenol from aqueous solutions. The adsorption results can be described by Langmuir isotherm, and the adsorption capacities were 200mg/g and 125mg/g for 2,6-dichlorophenol and p-nitrophenol, respectively. To realize the quick separation and recycle, the magnetic CTAB/MMT was further strategized and synthesized. The adsorption equilibrium time was 15min for both contaminants; the ions’ strength showed a little bit of influence on the adsorption performance. In addition, compared with acidic condition, neutral condition was more beneficial to the adsorption reaction. Due to the addition of Fe₃O₄, the adsorption capacities of this magnetic nanocomposite for 2,6-dichlorophenol and p-nitrophenol were a little bit decreased, which were 170mg/g and 91mg/g, respectively. However, the magnetic nanocomposite can be separated within 30s under an external magnetic field, which would be useful in the practical application.