Stimulation of cytokine production in human peripheral blood mononuclear cells by an aqueous Chlorella extract

CPE is an aqueous extract of the edible micro alga Chlorella pyrenoidosa, which has been shown to have immunostimulatory effects in vivo. In the present study, CPE was evaluated for an ability to stimulate cytokine production by human peripheral blood mononuclear cells (PBMC). PBMC from healthy individuals were treated ex vivo for 24 hours with 1, 10 and 100 μg/mL CPE. This resulted in a marked increase in the level of IL-10, a regulatory cytokine, and strong stimulation of the T-helper-1 (Th1) cell cytokines, IFN-γ and TNF-α. In contrast, stimulation of representative T-helper-2 (Th2) cell cytokines, IL-4 and IL-13, was minor. CPE (1, 10 or 100 μg/mL) did not cause a proliferation of human PBMC suggesting that enhanced secretion of cytokines was not secondary to an increase in cell number. We conclude that CPE stimulation of human PBMC induces a Th1-patterned cytokine response and a strong anti-inflammatory regulatory cytokine response, observations that await confirmation in vivo.

An aqueous Chlorella extract inhibits IL-5 production by mast cells in vitro and reduces ovalbumin-induced eosinophil infiltration in the airway in mice in vivo

An aqueous extract of the edible microalga, Chlorella pyrenoidosa (CP) (1), has recently been tested for its immunomodulatory effects in a human clinical trial. Here, the CP extract was dialyzed and fractionated using Sephadex G 100 chromatography. The effects of a dialyzed aqueous CP extract, fraction 2, on mast cell mediator release in vitro and ovalbumin-induced allergic airway inflammation in vivo were examined. In vitro, treatment of mouse bone marrow-derived mast cells with 2 for 18 h significantly inhibited antigen (trinitrophenyl-BSA)-induced IL-5 production. In vivo, treatment of mice with 2 during ovalbumin sensitization and stimulation process significantly reduced eosinophil and neutrophil infiltration in the airways. Moreover, fractions obtained by size exclusion chromatography of 2 inhibited IgE-dependent cytokine GM-CSF production from human cord blood-derived mast cells. Taken together, these results suggest that 2 is composed of biopolymers with anti-allergic potential.

First isolation and structural determination of cyclic β-(1→2)-glucans from an alga, Chlorella pyrenoidosa

The aqueous extract of the edible green microalgae Chlorella pyrenoidosa is of interest because of its immunostimulatory activity. Some components in the extract have been identified previously, namely a unique type of arabinogalactan and a galactofuran. Further fractionation of this extract was accomplished by treating the aqueous solution of the fraction precipitated by addition of 1.5vol of 95% ethanol with cetyltrimethylammonium bromide. The residue obtained by concentration of the supernatant was fractionated further by anion-exchange chromatography and size-exclusion chromatography on Sephadex G-100. Two fractions from the latter column were retained, of which one was a starch-like alpha-(1-->4)-linked d-glucan with some alpha-(1-->6) branches, and the other contained a starch plus a mixture of beta-(1-->2)-d-glucans. ESI mass spectrometry was used to show that the mixture contained both cyclic and linear beta-(1-->2)-d-glucans in a cyclic:linear ratio of 64:36, based on intensities of mass spectral peaks. For the cyclic beta-(1-->2)-d-glucans, ring sizes ranged from 18 to 35 monosaccharides with the ring containing 21 glucose units (54% of the cyclic glucans) being greater than three times more abundant than the next most abundant component, the ring containing 22 glucose units (15%). No rings containing 20 glucose units were present. This is the first observation of cyclic beta-(1-->2)-d-glucans in algae, as far as we are aware. For the linear beta-(1-->2)-d-glucans, the component containing 20 glucoses was most abundant (35% of the linear glucans), while the component containing 21 glucose units was the next most abundant (17%). These relatively low-molecular-weight glucans had low immunostimulatory activity.

Phytochemical analysis of Hibiscus caesius using high performance liquid chromatography coupled with mass spectrometry

Various species in genus Hibiscus are traditionally known for their therapeutic attributes. The present study focused on the phytochemical analysis of a rather unexplored species Hibiscus caesius (H. caesius), using high-pressure liquid chromatography coupled with mass spectrometry (HPLC-MS). The analysis revealed five major compounds in the aqueous extract, viz. vanillic acid, protocatechoic acid, quercetin, quercetin glucoside and apigenin, being reported for the first time in H. caesius. Literature suggests that these compounds have important pharmacological traits such as anti-cancer, anti-inflammatory, anti-bacterial and hepatoprotective etc. however, this requires further pharmacological investigations at in vitro and in vivo scale. The above study concluded the medicinal potential of H. caesius.

Extraction of copper(II) ions from aqueous solutions with a methimazole-based ionic liquid

The recently synthesized ionic liquid (IL) 2-butylthiolonium bis(trifluoromethanesulfonyl)amide, [mimSBu][NTf2], has been used for the extraction of copper(II) from aqueous solution. The pH of the aqueous phase decreases upon addition of [mimSBu]+, which is attributed to partial release of the hydrogen attached to the N(3) nitrogen atom of the imidazolium ring. The presence of sparingly soluble water in [mimSBu][NTf2] also is required in solvent extraction studies to promote the incorporation of Cu(II) into the [mimSBu][NTf2] ionic liquid phase. The labile copper(II) system formed by interacting with both the water and the IL cation component has been characterized by cyclic voltammetry as well as UV−vis, Raman, and 1H, 13C, and 15N NMR spectroscopies. The extraction process does not require the addition of a complexing agent or pH control of the aqueous phase. [mimSBu][NTf2] can be recovered from the labile copper−water−IL interacting system by washing with a strong acid. High selectivity of copper(II) extraction is achieved relative to that of other divalent cobalt(II), iron(II), and nickel(II) transition-metal cations. The course of microextraction of Cu2+ from aqueous media into the [mimSBu][NTf2] IL phase was monitored in situ by cyclic voltammetry using a well-defined process in which specific interaction with copper is believed to switch from the ionic liquid cation component, [mimSBu], to the [NTf2] anion during the course of electrochemical reduction from Cu(II) to Cu(I). The microextraction−voltammetry technique provides a fast and convenient method to determine whether an IL is able to extract electroactive metal ions from an aqueous solution.

Extraction of silver(i) from aqueous solutions in the absence and presence of copper(ii) with a methimazole-based ionic liquid

The ionic liquid (IL) 2-butylthiolonium bis(trifluoromethanesulfonyl)amide, [mimSBu][NTf₂], facilitates the efficient extraction of silver(i) from aqueous media via interaction with both the cation and anion components of the IL. Studies with a conventional aqueous-IL two phase system as well as microextraction of silver(i) by a thick IL film adhered to an electrode monitored in situ by cyclic voltammetry, established that [mimSBu][NTf₂] can extract electroactive silver(i) ions from an aqueous solution. The pH of the aqueous phase decreases upon addition of [mimSBu]⁺, which is attributed to partial release of the hydrogen attached to the N(3) nitrogen atom of the imidazolium ring. The presence of silver(i) further increase the acidity of the aqueous phase as a consequence of coordination with the IL cation component. Voltammetric and ¹H and ¹³C NMR techniques have been used to establish the nature of the silver(i) complexes extracted, and show that the form of interaction with the IL differs from that outlined previously for the extraction of copper(ii). Insights on the competition established when silver(i) is extracted in the presence of copper(ii) are provided. Finally, it is noted that metallic silver can be directly electrodeposited at the electrode surface after extraction of silver(i) into [mimSBu][NTf₂] and that back extraction of silver(i) into aqueous media is achieved by addition of an acidic aqueous solution.

Chemically induced phosphorescence from manganese(II) during the oxidation of various compounds by manganese(III), (IV) break and (VII) in acidic aqueous solutions

Chemiluminescence was observed during the manganese(III), (IV) and (VII) oxidations of sodium tetrahydroborate, sodium dithionite, sodium sulfite and hydrazine sulfate in acidic aqueous solution. From the corrected chemiluminescence spectra, the wavelengths of maximum emission were 689±5 and 734±5 nm when the reactions were performed in sodium hexametaphosphate and sodium dihydrogenorthophosphate/ orthophosphoric acid environments, respectively. The corrected phosphorescence spectrum of manganese(II) sulfate in a solution of sodium hexametaphosphate at 77 K exhibited two peaks with maxima at 688 and 730 nm. The chemical and spectroscopic evidence presented strongly supported the postulation that the emission was an example of solution-phase chemically induced phosphorescence of manganese(II) thereby, confirming earlier predictions that the chemiluminescence from acidic potassium permanganate reactions originated from an excited manganese(II) species.

Photocatalytic degradation of dye effluent by titanium dioxide pillar pellets in aqueous solution

Photocatalytic oxidation (PCO) process is an effective way to deal with organic pollutants in wastewater which could be difficult to be degraded by conventional biological treatment methods. Normally the TiO2 powder in nanometre size range was directly used as photocatalyst for dye degradation in wastewater. However the titanium dioxide powder was arduous to be recovered from the solution after treatment. In this application, a new form of TiO2 (i.e. pillar pellets ranging from 2.5 to 5.3 mm long and with a diameter of 3.7 mm) was used and investigated for photocatalytic degradation of textile dye effluent. A test system was built with a flat plate reactor (FPR) and UV light source (blacklight and solar simulator as light source respectively) for investigating the effectiveness of the new form of TiO2. It was found that the photocatalytic process under this configuration could efficiently remove colours from textile dyeing effluent. Comparing with the TiO2 powder, the pellet was very easy to recovered from the treated solution and can be reused in multiple times without the significant change on the photocatalytic property. The results also showed that to achieve the same photocatalytic performance, the FPR area by pellets was about 91% smaller than required by TiO2 powder. At least TiO2 pellet could be used as an alternative form of photocatalyst in applications for textile effluent treatment process, also other wastewater treatment processes.

Near-ultraviolet chemiluminescence from the reaction of ammonia with hypobromite in aqueous solution

The chemiluminescence arising from the oxidation of ammonium chloride by sodium hypobromite in aqueous alkaline solution includes a series of peaks in the near-ultraviolet, which is not commonly observed in liquid-phase chemiluminescence. The dominant peak in that region has an intensity maximum at 292 nm and smaller peaks are observed at 313, 334 and 356 nm. The emitted photons are of similar energy to the Vergard–Kaplan transition of molecular nitrogen, a major product of this reaction. However, the spectral distribution is different to that of previously reported gas-phase chemiluminescence attributed to the Vergard–Kaplan transition.

Investigation into the temporal stability of aqueous standard solutions of psilocin and psilocybin using high performance liquid chromatography

This paper reports an investigation into the temporal stability of aqueous solutions of psilocin and psilocybin reference drug standards over a period of fourteen days. This study was performed using high performance liquid chromatography utilising a (955% vlv) methanol: 10 mM ammonium formate,
pH 3.5 mobile phase and absorption detection at 269 nm. It was found that the exclusion of light significantly prolonged the useful life of standards, with aqueous solutions of both psilocin and psilocybin being stable over a period of seven days.

Polypyrrole-coated electrospun nanofibre membranes for recovery of Au(III) from aqueous solution

In this paper, for the first time, polypyrrole-coated electrospun nanofibre mats have been used as separation membranes to electrolessly recover Au from aqueous [Au(III)Cl₄]− solutions, based on a continuous-flow membrane separation process. With a [Au(III)Cl₄]− solution passing through the nanofibre membrane, the Au(III) ions were converted into elemental Au. The gold recovered was deposited on the nanofibre membranes in the form of Au particles, as confirmed by EDX and XPS measurements. It has been found that the polypyrrole-coated electrospun nanofibres are good candidate membrane material for the recovery of Au, and the recovery efficiency is affected by the membrane thickness, the permeate flux rate and the initial [Au(III)Cl₄]− concentration.

Dietary omega 3 fatty acids decrease intraocular pressure with age by increasing Aqueous outflow

Purpose: To determine whether there is an association between dietary omega-3 (ω-3) fatty acid intake, age, and intraocular pressure (IOP) caused by altered aqueous outflow. Methods: Sprague–Dawley rats were fed either ω-3–sufficient (ω-3⁺) or ω-3–deficient (ω-3^–) diets from conception. The diets had 7% lipid content. The ω-3⁺ diet contained safflower, flaxseed, and tuna oils (5.5:1.0:0.5), and the ω-3^– diet contained safflower oil only. Intraocular pressure was measured at 5 to 40 weeks of age under light anesthesia (ω-3⁺, n = 39; ω-3^–, n = 48). Aqueous outflow was determined at 45 weeks in a subgroup of animals (ω-3⁺, n = 15;ω-3^–, n = 22) using pulsed infusion. Ciliary body tissues (n = 6 per group) were assayed for fatty acid content by thin-layer and gas-liquid chromatography in both diet groups. Results: Animals raised on ω-3⁺ diets had a 13% decrease in IOP at 40 weeks of age (13.48 ± 0.32 mm Hg vs. 15.46 ± 0.29 mm Hg; P < 0.01). When considered as a change in IOP relative to 5 weeks of age, the ω-3⁺ group showed a 23% decrease (P < 0.001). This lower IOP in the ω-3⁺ diet group was associated with a significant increase (+56%; P < 0.001) in outflow facility and a decrease in ocular rigidity (–59%; P < 0.001). The ω-3⁺ group showed a 3.3 times increase in ciliary body docosahexaenoic acid (P < 0.001). Conclusions: Increasing dietary ω-3 reduces IOP with age because of increased outflow facility, likely resulting from an increase in docosanoids. This indicates that dietary manipulation may provide a modifiable factor for IOP regulation. However, further studies are needed to consider whether this can modify the risk for glaucoma and can play a role in treatment of the disease.

Anion recognition and sensing in organic and aqueous media using luminescent and colorimetric sensors

This review article focuses primarily on the work carried in our laboratories over the last few years using luminescent and colorimetric sensors, where the anion recognition occurs through hydrogen bonding in organic or aqueous solvents. This review begins with the story of the discovery of fluorescent photoinduced electron transfer (PET) sensors for anions using charged neutral urea or thiourea receptors where both fluorescent and NMR spectroscopic methods monitored anion recognition. This work led to the development of dual luminescent and colorimetric anion sensors based on the use of the ICT based naphthalimide chromophore, where ions such as fluoride gave rise to changes in both the fluorescence and the absorption spectra of the sensors, but at different concentrations. Here, the former changes were due to hydrogen bonding interactions, whereas the latter was due to the deprotonation of acidic protons, giving rise to the formation of the bifluoride anion (HF2−). Modification of the 4-amino-l,8-naphthalimide moiety has facilitated the formation of colorimetric anion sensors that work both in organic or aqueous solutions. Such charge neutral receptor motifs have also been incorporated into organic scaffolds with norbomyl and calixarene backbones, which have enabled us to produce anion directed self-assembled structures.

Analysis of cardioprotective effects using purified Saliva miltiorrhiza extract on isolated rat hearts

The purpose of the current study is to evaluate the cardioprotective effects of purified Salvia miltiorrhiza extract (PSME) on myocardial ischemia/reperfusion injury in isolated rat hearts. Hearts were excised and perfused at constant flow (7 – 9 ml · min⁻¹) via the aorta. Non-recirculating perfusion with Krebs-Henseleit (KH) solution was maintained at 37°C and continuously gassed with 95% O₂ and 5% CO₂. KH solution with or without PSME (100 mg per liter solution) was used after 30-min zero-flow ischemia for the PSME and control group, respectively. Left ventricular (LV) developed pressure; its derivatives, diastolic pressure, and so on were continuously recorded via a pressure transducer attached to a polyvinylchloride balloon that was placed in the left ventricle through an incision in the left atrium. PSME treated hearts showed significant postischemic contractile function recovery (developed pressure recovered to 44.2 ± 4.9% versus 17.1 ± 5.7%, P<0.05; maximum contraction recovered to 57.2 ± 5.9% versus 15.1 ± 6.3%, P<0.001; maximum relaxation restored to 69.3 ± 7.3% versus 15.4 ± 6.3%, P<0.001 in the PSME and control group, respectively). Significant elevation in end-diastolic pressure, which indicated LV stiffening in PSME hearts might have resulted from the excess high dose of PSME used. Further study will be conducted on the potential therapeutic value with lower dose of PSME on prevention of ischemic heart disease.