Gluconic acid aqueous solution: A bio-based catalytic medium for organic synthesis

Gluconic acid is non-toxic, non-volatile, non-corrosive, and easily biodegradable chemical, which can be produced from biomass using several methods: oxidation by molecular oxygen using heterogeneous catalysis, enzymatic oxidation, and microbial fermentation. Being highly soluble in water, gluconic acid can form concentrated aqueous solutions, and its 50% aqueous solution has found application as a catalytic medium for organic synthesis. For some reactions, gluconic acid aqueous solutions (GAAS) outperform conventional and green solvents when used as media for organic synthesis. GAAS was found to be particularly efficient in the Knoevenagel condensation, the Michael addition, and multicomponent reactions based on them. These and other chemical transformations utilizing GAAS as a medium are discussed in this review. We also compare the effectiveness of GAAS as a new green catalytic medium and the performance of other solvents and catalysts.     

浅谈绿色治疗婴幼儿湿疹

目的观察中药内服外用兼针灸治疗婴幼儿湿疹的疗效。方法将82例婴幼儿湿疹患儿分为观察组和对照组,观察组43例,对照组39例,观察组采用内服加减消风导赤汤,外用肤乐霜,加针灸治疗;对照组采用西医抗组胺类药、抗生素、皮质类固醇激素等全身治疗和局部治疗。结果观察组有效率为97.7%,治愈率为72.1%;对照组有效率为79.5%,治愈率为59.0%。结论中药内服外用兼针灸治疗婴幼儿湿疹疗效显著,明显优于单纯西医治疗。中医治疗婴幼儿湿疹具有安全可靠、毒副作用小、疗效持久、复发率低的特点。     

Influence of rearing water temperature on induced gonadal development and spawning behaviour of tropical green mussel,Perna viridis

ObjectiveTo standardize the technique of induced breeding and spawning of green mussel Perna viridis (P. viridis), in captivity.MethodsIn Experiment-A, the temperature was increased at a rate of 2 °C/5 days interval. In Experiment-B, a rise of 3 °C/5 days was practiced, whereas in Experiment C and D, respectively 4 and 5 °C was increased in 5 days interval. The temperature was maintained constant at 20 °C in the Control.ResultsThe increase in temperature showed a progressive effect on the gonadal development of mussels. The gonads ripped at 30 to 32 °C in all the experimental tanks, irrespective of the difference in temperature hike. Complete spawning in P. viridis was achieved by gradually raising the temperature from 20 to 35 °C at a rate of 3 or 4 °C/5 days.ConclusionAccording to the present study temperature induced spawning method is very simple and cost effective and can accelerate the production of mussel seeds in hatchery units and further stock improvement through genetic manipulation.     

Perspectives for the use of biotechnology in green chemistry applied to biopolymers,fuels and organic synthesis: from concepts to a critical point of view

Since the eighteenth century, after the first industrial revolution, humans have been exploiting the planet's natural resources in an unsustainable manner. This has caused some irreversible impacts on the environment. Because of this, we are facing a change of philosophy within the scientific community about chemical and industrial processes. During the 1990s, the concepts of green chemistry began to solidify, while in parallel some major advances in biotechnology were achieved through developments of genomic sciences and genetic and metabolic engineering. This work will discuss some new insights into the use of biotechnology as an important tool in green chemistry, showing new applications to biopolymers, biofuels and as a new alternative to traditional organic synthesis, making chemical processes more sustainable and less damaging to the planet.     

Dye functionalized cryogel columns for reversible lysozyme adsorption

In this study, poly (methyl methacrylate–glycidyl methacrylate) [poly(MMA-GMA)] cryogels were prepared by radical cryocopolymerization of MMA with GMA as a functional comonomer. Reactive Green 19 dye was then attached to the cryogel by nucleophilic substitution reaction, and this dye-attached cryogel column was used for lysozyme adsorption. Characterization of the cryogel was performed by Fourier transform infrared spectroscopy, environmental scanning electron microscopy, Brunauer–Emmett–Teller, and energy dispersive X-ray analysis. Pore size of the cryogels was 15–30?μm and pores were interconnected structure. Attached amount of Reactive Green 19 to cryogel support was calculated as 106.25?μmol/g cryogel. Lysozyme adsorption studies were carried out by using a continuous system. It was found that the maximum amount of lysozyme adsorption (32?mg/g cryogel) obtained from experimental results was found to be approximately same with the calculated Langmuir adsorption capacity (33?mg/g cryogel). Desorption of adsorbed lysozyme was carried out by using 1.5?M NaCl in pH 4.5 acetate buffer, and desorption yield was found to be 97.4%. Cryogels were very stable, and it was found that there was no remarkable reduction in the adsorption capacity at the end of ten adsorption–desorption cycles. As a result, Reactive Green 19-attached cryogels have great advantages such as easy preparation, rapid adsorption, and desorption, being economic and allowing the direct separation of proteins.     

Effect of commercially available green and black tea beverages on drug-metabolizing enzymes and oxidative stress in Wistar rats

The effect of commercially available green tea (GT) and black tea (BT) drinks on drugmetabolizing enzymes (DME) and oxidative stress in rats was investigated. Male Wistar rats were fed a laboratory chow diet and GT or BT drink for 5 weeks. Control rats received de-ionized water instead of the tea drinks. Rats received the GT and BT drinks treatment for 5 weeks showed a significant increase in hepatic microsomal cytochrome P450 (CYP) 1A1 and CYP1A2, and a significant decrease in CYP2C, CYP2E1 and CYP3A enzyme activities. Results of immunoblot analyses of enzyme protein contents showed the same trend with enzyme activity. Significant increase in UDP-glucuronosyltransferase activity and reduced glutathione content in liver and lungs were observed in rats treated with both tea drinks. A lower lipid peroxide level in lungs was observed in rats treated with GT drink. Electrophoretic mobility shift assay revealed that both tea drinks decreased pregnane X receptor binding to DNA and increased nuclear factor-erythroid 2 p45-related factor 2 binding to DNA. These results suggest that feeding of both tea drinks to rats modulated DME activities and reduced oxidative stress in liver and lungs. GT drink is more effective on reducing oxidative stress than BT drink.     

Deep eutectic solvent mediated rapid and selective one-pot synthesis of 5-alkylidene-Thiazolones

Deep eutectic solvents (DESs) were used as environmentally benign and straightforward replacements for the harmful organic solvents and transition metal-based catalysts in various organic syntheses. Here, we report a DES as a mild, biocompatible, and environmentally friendly dual solvent/catalyst for the one-pot construction of 2-amino-5-alkylidenethiazol-4-ones throw one-pot reaction of carbonyl compounds, nitrogen compounds, and rhodanine up to quantitative yields within a latent period of times. This green procedure has a more diverse and broader scope regarding starting materials and exhibits excellent conversion and high selectivity. In particular, DES displays better durability and reusability in the multicomponent reactions than traditional catalysts and solvents without distinct deterioration in catalytic activity.     

蛇床子汤外阴阴道冲洗联合硝酸咪康唑栓治疗湿热下注型霉菌性阴道炎随机平行对照研究

[目的]观察蛇床子汤外阴阴道冲洗配合硝酸咪康唑栓治疗湿热下注型霉菌性阴道炎疗效。[方法]使用随机平行对照方法,将128例门诊患者按就诊顺序编号分为两组。对照组60例硝酸咪康唑1枚/次,1次/d,阴道用药;治疗组68例蛇床子汤洗剂(蛇床子、苦参、百部、黄柏、白鲜皮、明矾、荆芥、川椒),250mL/次,1次/d,外阴阴道冲洗;硝酸咪康唑栓治疗同对照组。两组均连续治疗7d为1疗程。观测临床症状、阴道分泌物、不良反应。治疗1疗程,判定疗效。[结果]治疗组显效50例,有效15例,无效3例,总有效率95.59%。对照组显效25例,有效24例,无效11例,总有效率81.67%。治疗组疗效优于对照组(P0.05)。[结论]蛇床子汤外阴阴道冲洗联合硝酸咪康唑栓治疗湿热下注型霉菌性阴道炎效果显著,值得推广。     

Microwave accelerated green approach for tailored 1,2,3–triazoles via CuAAC

The persistent deterioration of our environmental assets has initiated ‘a push’ among the scientific community for increased reliance on eco-friendly methodologies minimizing the utilization of hazardous materials. As an outcome, there is a paradigm shift in the synthetic modules of organic reactions from conventional techniques to the parameters of green principles. Therefore, the demand for microwave (μw) tailored reactions has witnessed substantial and exponential growth in the last two decades. In accordance, the employment of green methodology in Cu(I) catalyzed alkyne-azide cycloaddition reaction (CuAAC) for the synthesis of 1,2,3–triazole derivatives have reared fruitful results with the reduction of synthetic time, superior yields without benign solvents. The use of the microwave technique has been amplified with its implementation of a range of green methodologies by contributing to solvent-less, catalyst-free, use of ionic liquids and aqueous medium. This review puts forward the microwave synthesis of 1,2,3–triazoles through Cu(I) mediated click chemistry.