Studies of adsorption for heavy metal ions and degradation of methyl orange based on the surface of ion-imprinted adsorbent

In order to prepare a novel adsorbent which can not only degrade organic compound, but also adsorb the heavy metal ions, immobilization of nanometer titanium dioxide on ion-imprinted chitosan carries was investigated. The amount of TiO₂, different kinds and amounts of dispersants, adding methods of TiO₂, different kinds of cross-linking agents and target metal ions are important factors influencing the degradation of Methyl Orange (MO) and the adsorption for Ni²⁺. When 15% amount of TiO₂ was added in preparation, the removal of MO was highly increased to nearly 90%, which was about eight times higher than that without TiO₂, at the same time, the effect of TiO₂ on the adsorption capacity was not obvious. The results show that in the presence of Ni²⁺ and MO, the MO could be removed effectively and the removal of MO reached 95.4%. At the initial concentration of Ni²⁺ of 200 mg/L, the adsorption capacity of Ni²⁺ reached 33 mg/g in the presence of MO.     

Supermacroporous hydrophobic affinity cryogels for protein chromatography

N-Methacryloyl-l-tryptophan (MATrp) containing poly(2-hydroxyethyl methacrylate) based supermacroporous cryogel [PHEMATrp] was prepared for lysozyme purification form chicken egg white. MATrp was synthesized by reacting methacryloyl chloride with l-tryptophan methyl ester and provided hydrophobic functionality to the cryogel. PHEMATrp cryogel with 60–100 μm pore size was obtained by free radical polymerization of HEMA and MATrp having a specific surface area of 50 m²/g. PHEMATrp cryogel was characterized by swelling studies, FTIR and SEM. The equilibrium swelling ratios of the cryogels were 7.18 g H₂O/g for PHEMA and 6.99 g H₂O/g for PHEMATrp. Lysozyme adsorption experiments were investigated under different conditions in continuous system (i.e., medium pH, flow-rate, protein concentration, temperature, salt type). Lysozyme adsorption capacity of PHEMA and PHEMATrp cryogels from aqueous solutions was estimated as 2.9 and 46.8 mg/g (0.49 and 7.85 mg/mL), respectively. Lysozyme molecules were desorbed with 0.5 M ethylene glycol solution with 91% recovery. It was observed that PHEMATrp cryogel can be used without significant decrease in lysozyme adsorption capacity after five adsorption–desorption cycles. PHEMATrp cryogel was used for the purification of lysozyme from chicken egg white. Purity of lysozyme was estimated by SDS-PAGE. Possible denaturation of purified lysozyme was checked with fluorimetric measurements. Specific activity of the purified lysozyme was found as 43,140 U/mg using Micrococcus lysodeikticus as substrate.     

Adsorption of Cu(II), Cd(II), and Pb(II) from aqueous single metal solutions by succinylated mercerized cellulose modified with triethylenetetramine

This study describes the preparation of two new chelating materials derived from succinylated mercerized cellulose (cell 1). Cell 1 was activated through two different methods by using diisopropylcarbodiimide and acetic anhydride (to form an internal anhydride) and reacted with triethylenetetramine in order to obtain cell 2 and 4. New modified celluloses were characterized by mass percent gain, concentration of amine functions, elemental analysis, and infrared spectroscopy. Cell 2 and 4 showed degrees of amination of 2.8 and 2.3 mmol/g and nitrogen content of 6.07% and 4.61%, respectively. The capacity of cell 2 and 4 to adsorb Cu²⁺, Cd²⁺, and Pb²⁺ ions from single aqueous solutions were examined. The effect of contact time, pH, and initial concentration of metal ions on the metal ions uptake was also investigated. Adsorption isotherms were well fitted by the Langmuir model. The maximum adsorption capacity of cell 2 and 4 were found to be 56.8 and 69.4 mg/g for Cu²⁺; 68.0 and 87.0 mg/g for Cd²⁺; and 147.1 and 192.3 mg/g for Pb²⁺, respectively.     

Adsorption of Cu(II), Cd(II), and Pb(II) from aqueous single metal solutions by mercerized cellulose and mercerized sugarcane bagasse chemically modified with EDTA dianhydride (EDTAD)

This work describes the preparation of new chelating materials derived from cellulose and sugarcane bagasse for adsorption of Cu²⁺, Cd²⁺, and Pb²⁺ ions from aqueous solutions. The first part involved the mercerization treatment of cellulose and sugarcane bagasse with NaOH 5 mol/L. Non- and mercerized cellulose and sugarcane bagasse were then reacted with ethylenediaminetetraacetic dianhydride (EDTAD) in order to prepare different chelating materials. These materials were characterized by mass percent gain, X-ray diffraction, FTIR, and elemental analysis. The second part consisted of evaluating the adsorption capacity of these modified materials for Cu²⁺, Cd²⁺, and Pb²⁺ ions from aqueous single metal solutions, whose concentration was determined by atomic absorption spectroscopy. These materials showed maximum adsorption capacities for Cu²⁺, Cd²⁺, and Pb²⁺ ions ranging from 38.8 to 92.6 mg/g, 87.7 to 149.0 mg/g, and 192.0 to 333.0 mg/g, respectively. The modified mercerized materials showed larger maximum adsorption capacities than modified non-mercerized materials.     

Bacterial cellulose nanofibers for albumin depletion from human serum

Cibacron Blue F3GA (CB) was covalently attached onto the bacterial cellulose (BC) nanofibers for human serum albumin (HSA) depletion from human serum. The BC nanofibers were produced by Acetobacter xylinum in the Hestrin–Schramm medium in a static condition for 14 days. The CB content of the BC nanofibers was 178 μmol/g. The specific surface area of the BC nanofibers was determined to be 914 m²/g. HSA adsorption experiments were performed by stirred-batch adsorption. The non-specific adsorption of HSA on the BC nanofibers was very low (1.4 mg/g polymer). CB attachment onto the BC nanofibers significantly increased the HSA adsorption (1800 mg/g). The maximum HSA adsorption was observed at pH 5.0. The HSA adsorption capacity decreased drastically with an increase of the aqueous phase concentration of sodium chloride. The elution studies were performed by adding 1 M NaCl to the HSA solutions in which adsorption equilibria had been reached. The elution results demonstrated that the binding of HSA to the adsorbent was reversible. The depletion efficiencies for HSA were above 96.5% for all studied concentrations. Proteins in the serum and eluted portion were analyzed by SDS-PAGE for testing the efficiency of HSA depletion from human serum. Eluted proteins include mainly HSA.     

Preparation of a biocatalyst via physical adsorption of lipase from Thermomyces lanuginosus on hydrophobic support to catalyze biolubricant synthesis by esterification reaction in a solvent-free system

Lipase from Thermomyces lanuginosus (TLL) was immobilized on mesoporous hydrophobic poly-methacrylate (PMA) particles via physical adsorption (interfacial activation of the enzyme on the support). The influence of initial protein loading (5–200 mg/g of support) on the catalytic properties of the biocatalysts was determined in the hydrolysis of olive oil emulsion and synthesis of isoamyl oleate (biolubricant) by esterification reaction. Maximum adsorbed protein loading and hydrolytic activity were respectively ≈100 mg/g and ≈650 IU/g using protein loading of 150 mg/g of support. The adsorption process followed the Langmuir isotherm model (R² = 0.9743). Maximum ester conversion around 85% was reached after 30 min of reaction under continuous agitation (200 rpm) using 2500 mM of each reactant in a solvent-free system, 45 °C, 20% m/v of the biocatalyst prepared using 100 mg of protein/g of support. Apparent thermodynamic parameters of the esterification reaction were also determined. Under optimal experimental conditions, reusability tests of the biocatalyst (TLL-PMA) after thirty successive cycles of reaction were performed. TLL-PMA fully retained its initial activity up to twenty two cycles of reaction, followed by a slight decrease around 8.6%. The nature of the product (isoamyl oleate) was confirmed by attenuated total reflection Fourier transform infrared (ATR-FTIR), proton (¹H NMR) and carbon (¹³C NMR) nuclear magnetic resonance spectroscopy analyses.     

Application of seaweeds for the removal of lead from aqueous solution

Ten different seaweed species were compared on the basis of lead uptake at different pH conditions. The brown seaweed, Turbinaria conoides, exhibited maximum lead uptake (at pH 4.5) and hence was selected for further studies. Sorption isotherms, obtained at different pH (4–5) and temperature (25–35 °C) conditions were fitted using Langmuir and Sips models. According to the Langmuir model, the maximum lead uptake of 439.4 mg/g was obtained at optimum pH (4.5) and temperature (30 °C). The Sips model better described the sorption isotherms with high correlation coefficients at all conditions examined. Various thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated indicating that the present system was a spontaneous and endothermic process. Through potentiometric titrations, number of binding sites (carboxyl groups) and pK₁ were determined as 4.1 mmol/g and 4.4, respectively. The influence of co-ions (Na⁺, K⁺, Mg²⁺ and Ca²⁺) on lead uptake was well pronounced in the case of divalent ions compared to monovalent ions. The solution of 0.1 M HCl successfully eluted all lead ions from lead-loaded T. conoides biomass. The regeneration experiments revealed that the alga could be successfully reused for five cycles without any loss in lead biosorption capacity. A glass column (2 cm i.d. and 35 cm height) was used to study the continuous lead biosorption performance of T. conoides. At 25 cm (bed height), 5 ml/min (flow rate) and 100 mg/l (initial lead concentration), T. conoides exhibited lead uptake of 220.1 mg/g. The column was successfully eluted using 0.1 M HCl, with elution efficiency of 99.7%.     

Assessment of hydrocarbon biodegradability in clayed and weathered polluted soils

Hydrocarbon biodegradation in clayed and weathered polluted soils is a challenge; thus the aim of the present study was to determine the best experimental conditions that improve the hydrocarbon biodegradability in clayed and weathered polluted soils, modifying the nitrogen and phosphorous content considering the C:N:P ratio and the water content as a percentage of the water-holding capacity of the soil. Biodegradation tests were performed in microcosms containing 20 g of dry soil at 30 °C. A uniform-precision central composite design of second order with three levels was used to assess the effect of nutrient and water content adjustment on the hydrocarbon degradation rate, total carbon consumption, and microbial activity. The results showed that the water-holding capacity corresponding to 350% and a C:N:P ratio of 100:7.5:0.66 were the best experimental conditions for obtaining the highest hydrocarbon degradation rate (1145 mg TPH kg^?1 dry soil day^?1), whereas the hydrocarbon degradation rate in a non-stimulated control was only 129 mg TPH kg^?1 dry soil day^?1. Water content was the factor that showed the highest significant effect (p ≤ 0.05) on the hydrocarbon degradation rate. The results of the present study allowed the achievement of the best experimental conditions that enhance hydrocarbon biodegradability in clayed and weathered polluted soils. Also, these conditions are proposed for use as a biodegradability assay.     

Synchronization of Boron application methods and rates is environmentally friendly approach to improve quality attributes of Mangifera indica L. On sustainable basis

Micronutrient deficiency in the soil is one of the major causes of mango fruit and yield's poor quality. Besides, the consumption of such a diet also causes a deficiency of micronutrients in humans. Boron deficiency adversely affects the flowering and pollen tube formation, thus decreasing mango yield and quality attributes. Soil and foliar application of B are considered a productive method to alleviate boron deficiency. A field experiment was conducted to explore the Boron most suitable method and application rate in mango under the current climatic scenario. There were nine treatments applied in three replications. The results showed that application of T8 = RD + Borax (75 g plant ^-1 as a basal application) + H₃ BO₃ (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant ^-1 as a basal application) + H₃ BO₃ (0.8% as a foliar spray) significantly enhanced the nitrogen, potassium, proteins, ash, fats, fiber, and total soluble solids in mango as compared to the control. A significant decrease in sodium, total phenolics contents, antioxidant activity, and acidity as citric acid also validated the effective functioning of T8 = RD + Borax (75 g plant ^-1 as a basal application) + H₃ BO₃ (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant ^-1 as a basal application) + H₃ BO₃ (0.8% as a foliar spray) as compared to control. In conclusion, T8 = RD + Borax (75 g plant ^-1 as a basal application) + H₃ BO₃ (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant ^-1 as a basal application) + H₃ BO₃ (0.8% as a foliar spray) is a potent strategy to improve the quality attributes of mango under the changing climatic situation.     

Immobilized Candida antarctica lipase B on ZnO nanowires/macroporous silica composites for catalyzing chiral resolution of (R,S)-2-octanol

ZnO nanowires were successfully introduced into a macroporous SiO₂ by in situ hydrothermal growth in 3D pores. The obtained composites were characterized by SEM and XRD, and used as supports to immobilize Candida antarctica lipase B (CALB) through adsorption. The high specific surface area (233 m²/g) and strong electrostatic interaction resulted that the average loading amount of the composite supports (196.8 mg/g) was 3–4 times of that of macroporous SiO₂ and approximate to that of a silica-based mesoporous material. Both adsorption capacity and the activity of the CALB immobilized on the composite supports almost kept unchanged as the samples were soaked in buffer solution for 48 h. The chiral resolution of 2-octanol was catalyzed by immobilized CALB. A maximum molar conversion of 49.1% was achieved with 99% enantiomeric excess of (R)-2-octanol acetate under the optimal condition: a reaction using 1.0 mol/L (R,S)-2-octanol, 2.0 mol/L vinyl acetate and 4.0 wt.% water content at 60 °C for 8 h. After fifteen recycles the immobilized lipase could retain 96.9% of relative activity and 93.8% of relative enantioselectivity.     

Involvement of potassium channels in the antidepressant-like effect of venlafaxine in mice

AimsStudies have shown that the acute administration of venlafaxine elicits an antidepressant-like effect in the mouse forced swim test (FST) by a mechanism dependent on the l-arginine–nitric oxide (NO)–cyclic guanosine monophosphate (cGMP) pathway. Because it has been reported that NO activates different types of potassium (K⁺) channels in the brain, this study investigated the involvement of K⁺ channels in the antidepressant-like effect of venlafaxine in the mouse FST.Main methodsMale adult Swiss mice were pretreated with different K⁺ channel inhibitors or openers 15 min before venlafaxine administration. After 30 min, the open-field test (OFT) and FST were carried out.Key findingsIntracerebroventricular (i.c.v.) pretreatment of mice with subeffective doses of tetraethylammonium (TEA, a non-specific inhibitor of K⁺ channels, 25 pg/site), glibenclamide (an ATP-sensitive K⁺ channel inhibitor, 0.5 pg/site), charybdotoxin (a large- and intermediate-conductance calcium-activated K⁺ channel inhibitor, 25 pg/site) or apamin (a small-conductance calcium-activated K⁺ channel inhibitor, 10 pg/site) was able to potentiate the action of a subeffective dose of venlafaxine (2 mg/kg, i.p.). Moreover, the reduction in the immobility time elicited by an effective dose of venlafaxine (8 mg/kg, i.p.) in the FST was prevented by the pretreatment of mice with the K⁺ channel openers cromakalim (10 µg/site, i.c.v.) and minoxidil (10 µg/site, i.c.v.). The drugs used in this study did not produce any change in locomotor activity.SignificanceThe results demonstrate that the neuromodulatory effects of venlafaxine, via the inhibition of K⁺ channels, are possibly involved in its anti-immobility activity in the mouse FST.     

Ruminal ochratoxin A degradation—Contribution of the different microbial populations and influence of diet

The mycotoxin ochratoxin A (OTA) is degraded extensively in the rumen. In this study, the relative contribution of different rumen microbial populations (MP) and the effect of diet on degradation of OTA were evaluated in a factorial design experiment. Degradation of OTA was quantified by using the Hohenheim gas test (HGT) in vitro fermentation system. Five different HGT diets were used (concentrate:forage proportions (C:F) – 10:90, 30:70, 50:50, 70:30, 90:10), and donor animals were fed diets with the respective ratio. Diets with the highest concentrate content were supplied with and without 10 g/kg sodium bicarbonate (70:30 BC and 90:10 BC). The MP included whole rumen fluid, fungi + protozoa, bacteria + protozoa, protozoa and bacteria + fungi. Protozoa numbers were counted after 24 h and OTA and ochratoxin alpha (OTα) analysed at 0, 4, 8, 12, 24 h. Area under the curve (AUC) and half-life were calculated for the latter two. The short average OTA half-life for whole rumen fluid of 2.6 h (1.3–4.5 h) demonstrates the high OTA degradation capacity of the rumen MP (i.e., standard HGT inoculum) and corresponds well with published in vivo results. Both MP and diet affected OTA degradation. Interactions among factors occurred (P<0.001), which made it necessary to do further comparisons within factor levels. Among MP, those with bacteria (bacteria + fungi and bacteria + protozoa) had lower AUC values (P<0.001) for OTA (196–673 ng/ml h, meaning higher degradation capacity, than those without bacteria (fungi + protozoa and protozoa; 701–1206 ng/ml h). Whole rumen fluid had the lowest AUC values (146–249 ng/ml h; P<0.05). Diet had a quadratic effect (P=0.001) on protozoal numbers with minimum values for the lowest and highest C:F ratios, for bacteria + protozoa, fungi + protozoa and protozoa, but no corresponding effect was found for OTA degradation parameters. While the generally high capacity to degrade OTA was confirmed, results for the contribution of different microbial groups shed new light on ruminal OTA degradation.     

Synthesis of thermo-sensitive copolymer with affinity butyl ligand and its application in lipase purification

In this study, thermo-sensitive N-alkyl substituted polyacrylamide polymer P_NNB was synthesized by using N-hydroxymethyl acrylamide(NHAM), N-isopropyl acrylamide (NIPA) and butyl acrylate (BA) as monomers, and its low critical solution temperature (LCST) was controlled to be 28 °C. The recovery of the thermo-sensitive polymer was over 98%. Butanol as a hydrophobic ligand was covalently attached onto polymer P_NNB and butyl ligand density was 80 μmol g^?1 polymer. The affinity polymer was used for purification of lipase from crude material. Optimized condition was pH 7.0, 35 °C adsorption temperature, 120 min adsorption time and 0.5 mg ml^?1 initial concentration of lipase. The adsorption isotherm accords with a typical Langmuir isotherm. The maximum adsorption capacity (Q_m) of the affinity polymer for lipase was 24.8 mg g^?1polymer. The affinity copolymer could be recycled by temperature-inducing precipitation and there was only about 6% loss of adsorption capacity after five recyclings. Specific activity of lipase was improved from 14 IU mg^?1 to 506 IU mg^?1 protein, and its recovery achieved 82%. The affinity polymer is suitable for the purification of target proteins from the crude material with large volume and dilute solution.     

Characterization of a naringinase from Aspergillus oryzae 11250 and its application in the debitterization of orange juice

Naringinase plays a rather important role in reducing the bitterness of juice by hydrolyzing naringin. A novel extracellular naringinase was purified from Aspergillus oryzae 11250 cultured in the presence of orange peel. A 26.78-fold purification rate was achieved by salt-induced precipitation, followed by anion-exchange and gel filtration chromatography with 32% recovery and specific activity of 2194.62 units per mg protein (U/mg). The optimum pH and temperature for naringinase activity were 5.0 and 45 °C, respectively. This enzyme was stable at 30 °C for 5 h. The K_m and V_max of naringinase toward naringin determined by Lineweaver-Burk method were 1.60 ± 0.13 mM and 126.21 ± 5.52 μmol/(min mg), respectively. The enzyme activity was inhibited completely by Ag⁺ at 10 mM. Naringinase is capable of hydrolyzing naringin, neohesperidin, and some other glycosides. A supplement of 6 U/mL of this naringinase in citrus juice sufficiently removed naringin to relieve the bitterness of citrus juice. These properties make the enzyme an ideal candidate for commercial application in the debitterization of orange juice.     

Bioconversion of post harvest crop residues and cattle shed manure into value-added products using earthworm Eudrilus eugeniae Kinberg

The post-harvest residues of some local crops, e.g. wheat (Triticum aestivum), millets (Penniseum typhoides and Sorghum vulgare), and a pulse (Vigna radiata) were subjected to recycle through vermicomposting by using the epigeic earthworm Eudrilus eugeniae Kinberg, under laboratory conditions. The crop residues were amended with animal dung; and three types of vermibeds were prepared: (i) millet straw (S. vulgare + Pennisenum typhoides in equal quantity) + sheep manure (1:2 ratio) (MS), (ii) pulse bran (Vigna radiata) + wheat straw (Triticum aestivum) + cow dung (1:1:2 ratio) (PWC), and (iii) mixed crop residues (mixing of all types crop residues, used in this study) + cow dung in 1:1 ratio (MCR + CD). The fourth treatment was cattle shed manure (CSM). At the end, ready vermicompost showed lower organic C content and higher concentrations of other important plant nutrients. Organic C content decreased in the order: MCR + CD (27.6%) > PWC (22.8%) > CMS (22.6%) > MS (19.4%). The ready vermicompost obtained from MCR + CD vermibed showed the maximum increase (% of initial level) in content of total N (143.4%), available P (111.1%) and exchangeable K (100.0%). The end product showed reduction in C:N ration between the ranges of 60.7% (CSM) and 70.3% (MCR + CD), at the end. The composting earthworm E. eugeniae exhibited the highest values of biological parameters: maximum mean individual biomass (1261.25 ± 7.0 mg), biomass gain (955.84 ± 11.03 mg), growth rate (10.62 ± 0.10 mg wt. worm⁻¹ day⁻¹), cocoon numbers (87.67 ± 6.51), and reproduction rate (0.66 ± 0.01 cocoons worm⁻¹ day⁻¹) in CSM container, while MS vermibeds showed the lowest values of these parameters. During experimentation, the maximum mortality for E. eugeniae was recorded in MS (16.67 ± 7.63%) followed by CSM > PWC > MCR + CD. Results indicated that the C:N ratio of the substrate drastically influenced the growth parameters of E. eugeniae, and it showed the close relations with maximum individual biomass gain (R² = 0.96), individual growth rate (R² = 0.82), and reproduction rate (cocoon worm⁻¹ day⁻¹) (R² = 0.72), in different treatments. This study clearly indicates that vermicomposting of crop residues and cattle shed wastes can not only produce a value-added product (vermicomposting) but at the same time acts as best culture medium for large-scale production of earthworms.     

Calcium and mitochondrial metabolism in ceramide-induced cardiomyocyte death

Ceramides are important intermediates in the biosynthesis and degradation of sphingolipids that regulate numerous cellular processes, including cell cycle progression, cell growth, differentiation and death. In cardiomyocytes, ceramides induce apoptosis by decreasing mitochondrial membrane potential and promoting cytochrome-c release. Ca^2 + overload is a common feature of all types of cell death. The aim of this study was to determine the effect of ceramides on cytoplasmic Ca^2 + levels, mitochondrial function and cardiomyocyte death. Our data show that C₂-ceramide induces apoptosis and necrosis in cultured cardiomyocytes by a mechanism involving increased Ca^2 + influx, mitochondrial network fragmentation and loss of the mitochondrial Ca^2 + buffer capacity. These biochemical events increase cytosolic Ca^2 + levels and trigger cardiomyocyte death via the activation of calpains.     

Cardioprotective effects of lipoic acid,quercetin and resveratrol on oxidative stress related to thyroid hormone alterations in long-term obesity

This study investigated possible mechanisms for cardioprotective effects of lipoic acid (LA), quercetin (Q) and resveratrol (R) on oxidative stress related to thyroid hormone alterations in long-term obesity. Female C57BL/6 mice were fed on high-fat diet (HFD), HFD + LA, HFD + R, HFD + Q and normal diet for 26 weeks. Body weight, blood pressure, thyroid hormones, oxidative stress markers, angiotensin converting enzyme (ACE), nitric oxide synthase (NOS) and ion pump activities were measured, and expression of cardiac genes was analyzed by real-time polymerase chain reaction. HFD induced marked increase (P < .05) in body weight, blood pressure and oxidative stress, while plasma triidothyronine levels reduced. ACE activity increased (P < .05) in HFD mice (0.69 ± 0.225 U/mg protein) compared with controls (0.28 ± 0.114 U/mg protein), HFD + LA (0.231 ± 0.02 U/mg protein) and HFD + Q (0.182 ± 0.096 U/mg protein) at 26 weeks. Moreover, Na⁺/K⁺-ATPase and Ca^2 +-ATPase activities increased in HFD mice whereas NOS reduced. A 1.5-fold increase in TRα1 and reduction in expression of the deiodinase iodothyronine DIO1, threonine protein kinase and NOS3 as well as up-regulation of AT1α, ACE, ATP1B1, GSK3β and Cja1 genes also occurred in HFD mice. Conversely, LA, Q and R inhibited weight gain; reduced TRα1 expression as well as increased DIO1; reduced ACE activity and AT1α, ATP1B1 and Cja1 gene expression as well as inhibited GSK3β; increased total antioxidant capacity, GSH and catalase activity; and reduced blood pressure. In conclusion, LA, resveratrol and quercetin supplementation reduces obesity thereby restoring plasma thyroid hormone levels and attenuating oxidative stress in the heart and thus may have therapeutic potential in heart diseases.     

KMUP-1 ameliorates monocrotaline-induced pulmonary arterial hypertension through the modulation of Ca2+ sensitization and K+-channel

AimsThis study investigates the actions of KMUP-1 on RhoA/Rho-kinase (ROCK)-dependent Ca²⁺ sensitization and the K⁺-channel in chronic pulmonary arterial hypertension (PAH) rats.Main methodsSprague–Dawley rats were divided into control, monocrotaline (MCT), and MCT + KMUP-1 groups. PAH was induced by a single intraperitoneal injection (i.p.) of MCT (60 mg/kg). KMUP-1 (5 mg/kg, i.p.) was administered once daily for 21 days to prevent MCT-induced PAH. All rats were sacrificed on day 22.Key findingsMCT-induced increased right ventricular systolic pressure (RVSP) and right ventricular hypertrophy were prevented by KMUP-1. In myograph experiments, KCl (80 mM), phenylephrine (10 µM) and K⁺ channel inhibitors (TEA, 10 mM; paxilline, 10 µM; 4-AP, 5 mM) induced weak PA contractions in MCT-treated rats compared to controls, but the PA reactivity was restored in MCT + KMUP-1-treated rats. By contrast, in β-escin- or α-toxin-permeabilized PAs, CaCl₂-induced (1.25 mM, pCa 5.1) contractions were stronger in MCT-treated rats, and this action was suppressed in MCT + KMUP-1-treated rats. PA relaxation in response to the ROCK inhibitor Y27632 (0.1 μM) was much higher in MCT-treated rats than in control rats. In Western blot analysis, the expression of Ca²⁺-activated K⁺ (BK_Ca) and voltage-gated K⁺ channels (Kv2.1 and Kv1.5), and ROCK II proteins was elevated in MCT-treated rats and suppressed in MCT + KMUP-1-treated rats. We suggest that MCT-treated rats upregulate K⁺-channel proteins to adapt to chronic PAH.SignificanceKMUP-1 protects against PAH and restores PA vessel tone in MCT-treated rats, attributed to alteration of Ca²⁺ sensitivity and K⁺-channel function.     

Antibody purification with protein A attached supermacroporous poly(hydroxyethyl methacrylate) cryogel

Immunoglobulin G (IgG) purification from human plasma with protein A attached supermacroporous poly(hydroxyethyl methacrylate) [PHEMA] cryogel has been studied. PHEMA cryogel was prepared by bulk polymerization which proceeds in aqueous solution of monomer frozen inside a plastic syringe (cryo-polymerization). After thawing, the PHEMA cryogel contains a continuous matrix having interconnected pores of 10–200 μm size. Protein was covalently attached onto the PHEMA cryogel via cyanogen bromide (CNBr) activation. The maximum IgG adsorption on the PHEMA/protein A cryogel was found to be 83.2 mg/g at pH 7.4 from aqueous solutions. The non-specific IgG adsorption onto the PHEMA cryogel was about 0.38 mg/g. The macropore size of the cryogel makes it possible to process blood cells without blocking the column. Higher adsorption capacity was observed from human plasma (up to 88.1 mg/g). Adsorbed IgG was eluted using 0.1 M glycine–HCl buffer (pH 3.5) with a purity of 85%. PHEMA–protein A cryogel was used for repetitive adsorption/desorption of IgG without noticeable loss in IgG adsorption capacity after 10 cycles. PHEMA–protein A cryogel showed several advantages such as simpler preparation procedure, good selectivity for IgG purification from human plasma and good stability throughout repeated adsorption–desorption cycles.     

Effect of salinity on vanadate biosorption by Halomonas sp. GT-83: Preliminary investigation on biosorption by micro-PIXE technique

Thirty-eight soil samples were collected from crude oil contaminated land in south of Iran. Initial screening of a total of 100 bacterial isolates, resulted in the selection of one isolate with maximum adsorption capacity of 52.7 mg vanadate/g dry weight. It was tentatively identified as Halomonas sp. according to morphological and biochemical properties and named strain GT-83. Removal of vanadate by biosorption with Halomonas sp. GT-83 was very sensitive to solution pH. Vanadate adsorption decreased with increasing pH, with maximum adsorption capacities achieved in at pH 3.0 in the absence and in the presence of increasing concentrations of salt. Vanadate-salt biosorption studies were also performed at this pH value. Equilibrium uptakes of vanadate increased with increasing vanadate concentration up to 600 mg/l. Maximum metal removal (91.8%) took place at pH 3.0 with initial vanadate concentration of 100 mg/l, which got reduced (84.8%) in the presence of 50 g/l salt. The equilibrium sorption data were analyzed by using Freundlich isotherm. The specific uptake of vanadate increased at low cell concentration and decreased when cell concentration exceeded 0.75 g/l. The paper also demonstrates the potential value of micro-PIXE in biosorption studies.