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The targeted synthesis of an efficient, visible light active, recyclable, freestanding covalent organic framework thin film photocatalyst for multi-faceted photocatalysis is the essence of the proposed work. A simple, scalable, reagent free synthesis of a thin film at the interface of 5,10,15,20-tetra-(4-aminophenyl)porphyrin, 2-vinylbenzene-1,4-dicarbaldehyde in nitrobenzene and aqueous glyoxal affords centimetre sized continuous 2D thin film with substantial stability, flexibility and efficient visible light activity. Strikingly different from the regular imine based COF, the incorporation of the glyoxal unit as a modulator helps in band gap tuning and induces flexibility within the thin film. An interplay between time and concentration helps in achieving a thin film photocatalyst with efficient photocatalytic activity for 1,4-NADH regeneration and selective formic acid formation from CO2. The optimum band edge position of the thin film photocatalyst also enables solar fine chemical synthesis via reductive dehalogenation under visible light illumination with excellent recyclability. The present work gives insight into visible light active thin film formation en route to metal-free sustainable photocatalysis.

Solar light-driven fuel production from carbon dioxide using organic photocatalysts is a promising technique for sustainable energy sources. Band gap engineering in sustainable organic photocatalysts for improving efficiency and fulfilling the requirements is highly anticipated. Here, we present a new strategy to engineer the band gap in covalent organic framework (COF) photocatalysts by varying the push-pull electronic effect. To implement this strategy, we have designed and synthesized four different COFs using a tripodal amine 4,4',4″-(1,3,5-triazine-2,4,6-triyl)tris(([1,1'-biphenyl]-4-amine)) [Ttba] with 1,3,5-triformylbenzene (COF-1), 2,4,6-triformylphloroglucinol (COF-2), 2,4,6-triformylphenol (COF-3), and 2,4,6-triformylresorcinol (COF-4). On varying the number of hydroxyl units in the aldehyde precursor, the resulting COFs allow the fine-tuning of their band gap and band edge positions and result in different morphologies with varying surface areas. The enhanced optical properties of COF-3 and COF-4 with very suitable band gaps of 2.02 and 1.95 eV, respectively, enable them to demonstrate a high-efficiency photobiocatalytic system for NADH photoregeneration and enhanced visible light-driven formic acid production at a rate of 226.3 μmol g-1 in 90 min. The triazine core enables efficient charge separation, while the hydroxyl groups induce an electronic push-pull effect, regulating their photocatalytic efficiency. The results demonstrated the morphology-guided enhanced surface area and dual keto-enol tautomerism-induced push-pull effect in asymmetrical charge distribution as key features in the fine-tuning of the photocatalysts.

A novel BODIPY functionalized ruthenium-nitrogen doped graphene nanosheet photocatalyst is reported herein for the regioselective direct C–H arylation of imidazo-pyrimidines at the C-3 position with excellent functional-group tolerance. Organic transformation is achieved under visible light irradiation in high yields and selectivity (∼99%) using this photocatalyst. The results are a benchmark example for the use of functionalized graphene nanosheets as a highly practical and efficient visible light active photocatalyst for carrying out regioselective direct C–H arylation.

The synthesis of pharmaceutically active 1,2,3-triazoles has been continuously scrutinized in the search for unique and effective catalysts to make the process efficient, green, and sustainable. Here, we are presenting a new visible light active Ni(II) cyclam-integrated triazole-linked organic polymer (Ni-TLOP) photocatalyst for the synthesis of 1,2,3-triazole compounds with excellent efficiency and regioselectivity. The reaction was studied for a series of substrates and the absolute regioselectivity of a representative triazole product has also been confirmed by X-ray crystallography. The proficiency and chemical orthogonality of the Ni-TLOP are remarkable and it shows enhanced efficiency and regioselectivity. The use of a recyclable photocatalyst and non-hazardous reagents makes the catalytic system sustainable and environmentally friendly. This photocatalyzed click reaction technique has been successfully applied to the expedient synthesis of one of the most sold anti-epileptic drugs rufinamide.

Our growing energy demands must be met by a sustainable supply with reduced carbon intensity. One of the most exciting prospects to realize this goal is the photocatalyst-biocatalyst integrated artificial photosynthesis system which affords solar fuel/chemicals in high selectivity from CO2. Graphene based photocatalysts are highly suitable for the system, but their industrial scale use requires immobilization for improved separation and recovery of the photocatalyst. Therefore for practical purposes, design and fabrication of film type graphene photocatalyst with higher solar energy conversion efficiency is an absolute necessity. As a means to achieve this, we report herein the successful development of a new type of flexible graphene film photocatalyst that leads to >225% rise in visible light harvesting efficiency of the resultant photocatalyst-biocatalyst integrated artificial photosynthesis system for highly selective solar fuel production from CO2 compared to conventional spin coated graphene film photocatalyst. It is an important step towards the design of a new pool of graphene film based photocatalysts for artificial photosynthesis of solar fuels from CO2.

Novel in situ Se-doped carbon nitride (C3N4) nanosheets are synthesized for the first time by a facile one-pot two-step strategy. The as-prepared Se-doped C3N4 nanosheets show a high visible light driven formic acid production rate of 1.001 × 105 μmol gcat–1 h–1. It represents the highest value reported in literature for formic acid production from CO2 by visible light harvesting C3N4 photocatalysts. The exceptional photocatalytic activity is largely attributed to selenium-doped conjugated system besides porous nanosheet morphology of the photocatalyst. The presence of midgap state in carbon nitride (−0.35 V vs standard hydrogen electrode) due to Se doping is found to significantly extend the light absorption up to 570 nm thereby further enhancing light harvesting ability of the photocatalyst. The current work not only provides a facile and scalable route to synthesize highly efficient Se-doped carbon nitride (C3N4) nanosheet photocatalysts but also sheds light on devising new avenues for rational design ...

Photocatalytic CO2 reduction for solar fuel production has attracted considerable attention as it can simultaneously reduce the effects of worldwide fossil-fuel shortage and global warming. As a means to achieve this we herein report the facile and eco-friendly synthesis of highly active carbon nanodots-silica hybrid photocatalyst (CNDSH) by a reverse microemulsion method with a nonionic surfactant. The photocatalyst-biocatalyst coupled system developed using CNDSH as photocatalyst functions efficiently to carry out high NADH regeneration (74.10 ± 0.17 %) followed by its consumption in exclusive formic acid production (203.33 ± 1.9 µmol) from CO2. This research work is a benchmark example of carbon nanodots-silica hybrid photocatalyst system for solar fuel production and expected to trigger further interest in the development of efficient and eco-friendly CO2 reduction systems.

Two-dimensional covalent organic frameworks (2D COFs) are a class of crystalline polymers with a design controllable platform that may be developed into a new type of metal-free photocatalyst. The exploration of new frameworks is, however, critical for further progress in this emerging field. To realize their full potential in practical light harvesting applications, the fabrication of a film type photocatalyst is equally essential. Here, we report the successful development of a triazine based covalent organic framework (2D CTF) as an inexpensive and highly efficient visible light active flexible film photocatalyst for solar fuel production from CO2. For this research work, the condensation polymerization between cyanuric chloride and perylene diimide has been exploited for the first time as a new synthetic approach to the construction of 2D CTFs. The visible light-harvesting capacity, suitable band gap and highly ordered π electron channels contribute to the excellent performance of the film photocatalyst. The current study is a benchmark example of COF based photocatalysts for solar fuel production from CO2 and is expected to trigger further interest in potential solar energy conversion applications such as wearable devices.

The successful development of a photocatalyst/biocatalyst integrated system that carries out selective methanol production from CO2 is reported herein. The fine-tuned system was derived from a judicious combination of graphene-based visible light active photocatalyst (CCG-IP) and sequentially coupled enzymes. The covalent attachment of isatin-porphyrin (IP) chromophore to chemically converted graphene (CCG) afforded newly developed CCG-IP photocatalyst for this research endeavor. The current work represents a new benchmark for carrying out highly selective methanol formation from CO2 in an environmentally benign manner.

The photocatalyst-enzyme coupled system for artificial photosynthesis process is one of the most promising methods of solar energy conversion for the synthesis of organic chemicals or fuel. Here we report the synthesis of a novel graphene-based visible light active photocatalyst which covalently bonded the chromophore, such as multianthraquinone substituted porphyrin with the chemically converted graphene as a photocatalyst of the artificial photosynthesis system for an efficient photosynthetic production of formic acid from CO(2). The results not only show a benchmark example of the graphene-based material used as a photocatalyst in general artificial photosynthesis but also the benchmark example of the selective production system of solar chemicals/solar fuel directly from CO(2).

A natural compound plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) was isolated from the leaves of Plumbago auriculata and found to inhibit the enzyme, 8-amino-7-oxononanoate synthase (AONS, also known as 7-keto-8-aminopelargonate synthase, KAPAS) an IC 50 of 2.1 μM in vitro . Biotin supplement significantly rescued the plant injury caused by the plumbagin treatment, and this result confirmed the target site, AONS. Foliar application of 1000 ∼ 2000 μg/mL plumbagin in a greenhouse condition showed lethal activity against eight species of weeds, containing three grass species of Sorghum bicolor , Echinochloa crus-galli , Digitaria sanguinalis and five broad leaf species of Solanum nigrum , Aeschynomene indica , Abutilon avicennae , Xanthium strumarium , Calystegia japonica . Field trial of foliar application with plumbagin 2000 μg/mL have successfully controlled 10 ∼ 15 leaf-stages and 2 ∼ 3 m vine lengths of Sicyos angulatus at the natural habitats around riparian zone in the Nam-Han River in Korea. Visual symptom of desiccation might be induced by the physiological cellular leakage which was significantly dose dependent on the plumbagin treatment regardless of light.

E-mail: kilee@krict.re.krReceived January 24, 2014, Accepted February 25, 2014Key Words : Asymmetric reduction, β-Chloro ketone, Borane, Spiroborate ester, DuloxetineSerotonin and norepinephrine neurotransmitters are intimatelyinvolved in a number of neurochemical and physiologicalprocesses, such as depression and pain disorders. Selectiveserotonin or norepinephrine reuptake inhibitors are theimportant class of antidepressants, such as fluoxetine, niso-xetine, tomoxetine, and duloxetine featuring the structuralsimilarity of 1-ary-3-aminopropanol.

The depletion of fossil fuels, ecological problems associated with emissions climate change, growing world population, and future energy supplies are forcing the development of alternative resources for energy (heat and electricity), transport fuels and chemicals: the replacement of fossil resources with neutral biomass. Several options exist to cover energy supplies of the future, including solar, wind, and water power; however, chemical carbon source can get from biomass only. When used in combination with environmental friend production and processing technology, the use of biomass can be seen as a sustainable alternative to conventional chemical feedstocks. The biorefinery concept is analogous to today`s petroleum refinery, which produce multiple fuels and chemical products from petroleum. A biorefinery is a facility that integrates biomass conversion processes and equipment to produce fuels, power, and value-added chemicals from biomass. Biorefinery is the co-production of a spectrum of bio-based products (food, feed, materials, and chemicals) and energy (fuels, power, and heat) from biomass [definition IEA Bioenergy Task 42]. By producing multiple products, a biorefinery takes advantage of the various components in biomass and their intermediates therefore maximizing the value derived from the biomass feedstocks. A biorefinery could, for example, produce one or several low-volume, but high-value, chemical or nutraceutical products and a low-value, but high-volume liquid transportation fuel such as biodiesel or bioethanol. Future biorefinery may play a major role in producing chemicals and materials as a bridge between agriculture and chemistry that are traditionally produced from petroleum. Industrial biotechnology is expected to significantly complement or replace the current petroleum-based industry and to play an important role.

Acetolactate synthase (ALS) genes from Monochoria vaginalis resistant (R) and susceptible (S) biotypes against ALS inhibitors found in Korea revealed a single amino acid substitution of Proline (CCT), at 169th position based on the M. vaginalis ALS sequence numbering, to serine (TCT) in conserved domain A of the gene (equal to the proline 197 in Arabidopsis thaliana ALS gene sequence). A. thaliana plants transformed with the single mutated (Pro 169 to Ser) M. vaginalis ALS gene (including transit signal peptide) showed cross-resistance patterns to ALS-inhibiting herbicides, like as sulfonylurea-herbicide bensulfuron methyl (R/S factor of 9.5), imidazolinone-herbicide imazapyr (R/S factor of 5.1), and triazolopyrimidine-herbicide flumetsulam (R/S factor of 17.6) when measuring hypocotyls’ length of A. thaliana . The ALS activity from the transgenic A. thaliana plants confirmed the cross-resistance pattern to these herbicides like as R/S factor of 8.3 to bensulfuron methyl, 2.3 to imazapyr, and 13.2 to flumetsulam.

The validation of potential herbicide target, 7-keto-8-aminopelargonic acid synthase (KAPAS) in the early step of biotin biosynthesis pathway, was performed in vitro and in vivo with lead chemical triphenyltin acetate (TPTA). KAPAS activity was completely inhibited by TPTA with an IC 50 of 19.85 μM. 40-day-old Arabidopsis thaliana plants were killed with foliar treatment of 125 g ha −1 TPTA under the greenhouse conditions. The germination of A. thaliana seeds was also completely inhibited with 62.5 μM TPTA, but it was rescued to 85–92% with the supplement of biotin biosynthesis intermediates such as 0.5 mM of biotin, dethiobiotin, and 7,8-diaminopelargonic acid, but not by 7-keto-8-aminopelargonic acid (KAPA). However, additional supplement of 0.5 mM S -adenosyl- l -methionine (SAM) with 0.5 mM KAPA rescued up to 91% of the germination previously inhibited by the 50 μM TPTA. Also, biotin supplements alleviated the growth inhibition of 40-day-old A. thaliana plant. Foliar application of TPTA induced 8-fold higher substrate ( l -alanine) accumulation in the treated A. thaliana plants. RNA expression for KAPAS transcripts were much fainter in the lane representing leaf tissue treated with TPTA. With these results, we report that SAM is an essential donor of amino groups for synthesis of the biotin precursor KAPA to 7,8-diaminopelargonic acid (DAPA) synthesis in plants, that KAPAS is a potential herbicidal target site in the biotin biosynthesis pathway, and that TPTA might be one of the potential KAPAS inhibitors.

The methanol extract of dried roots of Euphorbia kansui, known as “Gan Sui” in oriental medicine, showed pesticidal activity against brown plant hopper (Nilaparvata lugens Stal) and two-spotted spider mite (Tetranychus urticae Koch). Bioassay-guided fractionation led to the isolation of two active compounds from the dried roots of E. kansui. The substances were identified as 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoylingenol (1) and 3-O-(2′E,4′Z-decadienoyl)-ingenol (2) by MS and NMR spectral data. Both compounds exhibited insecticidal activity against the brown plant hopper and compound 1 was active against the two-spotted spider mite. Compared to anise oil and eugenol, the two ingenane diterpenes showed greater activity against brown plant hopper. The results suggest that 3-O-(2,3-dimethylbutanoyl)-13-O-dodecanoylingenol and 3-O-(2′E,4′Z-decadienoyl)-ingenol could be used directly as natural pesticides or as lead principles for the control of brown plant hopper and two-spotted spider mite.

For the purpose of developing new oxime reactivators of acetylcholinesterases (AChE) that have been inhibited by organophosphorus agents, emphasis was given to the finding that the lipophilic nature of fluorinated compounds is responsible for their enhanced transport across the blood brain barrier (BBB). As a result, we have designed and synthesized the fluorinated oxime derivatives, which quantum mechanical calculations suggest should have a greater lipophilicity and BBB permeability than their non-fluorinated analogs. Among the compounds explored in this study, 4 was found to have the highest potency for reactivation of paraoxon-inhibited housefly (HF) AChE.

Hemicellulose, the second, most common polysaccharide in nature constitutes approximately 20—35% of lignocellulosic biomass. Effective utilization of biomass, hitherto underutilized, is gaining tremendous importance for the production of energy, fuels, and chemicals. Amongst the vast array of chemicals derived from lignocellulosics, furfural is the key chemical that finds wide applications in oil refining, plastics, pharmaceutical and agrochemical industries. There is no synthetic route for the production of furfural. A few conventional technologies currently in practice for its separation and subsequent isolation are appropriately reviewed. Major disadvantages associated with processes currently used for the production of furfural based on acid-catalyzed hydrolysis have been discussed. A need to develop a process which is devoid of all the shortcomings associated with conventional process is emphasized. Several important aspects of chemistry underlying the acid hydrolysis of xylose are discussed. The importance of myriad pre-treatment steps involved to surmount the physical and chemical barriers and to liberate xylose from the confines of acid-resistant layer of lignin has been emphasized. New developments in the production of furfural from cyclodehydration of xylose using solid acid catalysts in the recent past have been reviewed appropriately in present communication. Finally, the production of furfural and furfuryl alcohol, their domestic market and export in China deserve some coverage and therefore have appropriately been discussed as well. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd

Trehalase (EC 3.2.1.28) hydrolyses the non-reducing disaccharide trehalose, the main source of glucose in insects, nematodes, and fungi, into 2 glucose molecules. Therefore, development of specific and potent trehalase inhibitors as control agents against insect pests and other deleterious organisms has been of great interest. For the establishment of a 96-well microplate assay to detect trehalase activity, the o -toluidine method of glucose determination was deliberately modified with whole body extracts from housefly ( Musca domestica Linnaeus) larvae serving as an enzyme source. In the microplate trehalase assay, optical density (OD) at 630 nm increased proportionally with acetic acid concentration up to 90%, with the OD rate of increase greatest at 10% o -toluidine. Sensitivity in a 96-well plate reaction was slightly better than with spectrophotometric measurements, especially at low concentrations of glucose. Samples from 70% ammonium sulphate precipitation showed the greatest activity with minimum noise caused by endogenous reducing sugars and a maximum enzymatic activity at pH 4.5 and 40 °C, with substrate inhibition at trehalose concentrations greater than 320.0 mM. The I 50 values of the 2 trehalase inhibitors tested, amygdalin and validamycin A, were 31.7 mM and 0.4 mM, respectively. In conclusion, this 96-well microplate assay of trehalase activity using the whole body extract from housefly larvae as an enzyme source might be useful in discovery of potent trehalase inhibitors through the development of new insecticides from screening numerous synthetic and natural compounds.

New bis-pyridinium oxime reactivators 6 with CH 2 O(CH 2 ) 2 OCH 2 and CH 2 O(CH 2 ) 4 OCH 2 linkers between the two pyridinium rings were designed and synthesized. In the in vitro test of their potency to reactivate AChE inhibited by organophosphorus agents at 5 × 10 −3 M concentration, the reactivation ability of 1,2-dimethoxy-ethylene-bis- N , N ′-4-pyridiumaldoxime dichloride ( 6a ) was 63% for housefly (HF) AChE inhibited by diisopropyl fluorophosphates (DFP), 51% for bovine red blood cell (RBC) AChE inhibited by DFP, 67% for HF-AChE inhibited by paraoxon, and 81% for RBC-AChE inhibited by paraoxon. Except in the case of DFP-inhibited HF AChE test of 2-PAM, the activities of 6a are much higher than the activities of 2-PAM and HI-6 which are AChE reactivators currently in use.

The Inhibition of AChE activity was compared between susceptible and phenthoate resistant diamondback moth (DBM) using in vitro enzyme assay and native Polyacrylamide gel electrophoresis (PAGE). Dichlorvos and carbofuran were very effective to inhibit the AChE activity from S strains with I 50 values of 0.38 and 0.21 μM, respectively. However, the AChE from R strain was much less inhibited to dichlorvos, i.e. insensitive to dichlorvos with R/S ratio of 11.4, than phosphamidon, BPMC, and carbofuran with the R/S ratio of 2.8, 4.2, and 2.5, respectively. Direct-staining of native gel revealed that the majority of AChE from S strain was quickly deactivated by 50 μM of dichlorvos that was the lowest concentration of the inhibitor in the experiment. However, the AChE activity from R strain was not fully inhibited by 500 μM of dichlorvos. This result was confirmed in the repetitive experiment with head extracts of both strains separately prepared with three replications. In the incubation of AChE with 100 μM of dichlorvos on native gel, the AChE from R strain was apparently insensitive to the inhibitor in contrast to the fully inhibited AChE from S strain.

The inheritance of the phenthoate-selected diamondback moth (DBM) was investigated, and the cross resistance was also examined against various insecticides. The phenthoate concentration-mortality relationship between F 1 progenies (S♀ X R♂, S♂ X R♀) obtained from reciprocal crosses with the susceptible (S) and phenthoate-selected DBM strains (R) indicated the absence of sex-linked inheritance. The resistance ratios of F 1s (S♀ X R♂), F 1R (S♀ X R♂), and phenthoate-selected(R) strains were 23.8, 24.1, and 175.1, respectively. Degrees of dominance of the Fis and F 1R progenies were 0.23 and 0.45. These results suggest that the inheritance of phenthoate resistance in DBM is controlled by one or more autosomal genes in a manner of incomplete dominance. This R strain exhibited a high level of cross resistance to parathion, pyrachlofos, and phosmet with resistance ratios of 51.1, 59.9 and 72.5, respectively, and also showed medium level of cross resistance to most organophosphorus insecticides with the range of resistance ratios among 5.0 ∼ 50.0, except for acephate, demeton-S-methyl, profenofos, and pyridaphenthion showing low level of cross resistance with resistance ratios among 1.5-4.0. However, this R strain exhibited low level of cross resistance to most carbamate insecticides except BPMC showing resistance ratio of 5.3. Similar low level of cross resistance was observed from the pyrethroid and neonicotinoid insecticides with the resistance ratios among 1.2∼4.6.

An asymmetric artificial photosynthesis system that comprises an efficient method of nicotinamide cofactor regeneration under visible light employing a graphene-based light harvesting photocatalyst and its subsequent utilization in an enzyme-catalyzed asymmetric reduction of prochiral ketones is described.

A new endo-1,4-beta-xylanase gene (FJ380951), KRICT PX1, isolated from Paenibacillus sp. HPL-001, was expressed in E. coli. Enzyme purification, mutation, immobilization, and molecular simulation were conducted. The P1H1 mutant of one amino acid substitution (168Leu￫Gln) showing the strongest xylanase activity was selected among 250 mutant clones. The specific activity of the P1H1 xylanase was 53.3 U/mg protein at 50°C, an approximately fivefold increase compared to that of the original KRICT PX1 xylanase (10.25 U/mg protein) at the same condition of pH 5~10, and enhanced activity from 20.1 to 36.6 U/mg proteins at 60°C. The structural dynamics of the mutant P1H1 became stronger than that of the wild type, which could be eliminated by a helix deformation with the H-bond missing between Leu168 and Asp164 after mutation. Xylanase could be reused for 5 batches without significant loss of activity after being immobilized on surface functionalized silica-based mesoporous cellular foam. However, xylanase activity declined to 60% at the 10th batch. Further research on practical applications will be necessary for industrial usage.

A system constructed with thermocouples and a conventional refrigerating bath was used to measure the freezing and melting points of various developmental stages of oriental cockroach, Blatta orientalis L., after exposure to different pre-freezing temperature conditions. Low temperature exposure of the oriental cockroach was not consistently effective in enhancing the supercooling capacity at various stages. There were minimal differences among the various developmental stages, and freezing points ranged −6.85 to −11.18°C. A significant lowering of freezing point (P< 0.05) was observed only from the first and second nymphal stages; freezing points were below −11°C after exposure at 5°C after 2 wks at 10°C. The melting points were consistently around 0°C (range of −0.19 to 0.31 °C). The relatively limited supercooling capacity of oriental cockroaches suggest that freezing avoidance by microhabitat selection is a major mechanism for overwintering of this insect.

The distribution and inhibition of esterase activity among body of the resistant Crawford and susceptible CSMA strains of male German cockroach, Blattella germanica (L.), were evaluated with α- and β-naphthyl esters using a spectrophotometric assay and native polyacrylamide gel electrophoresis. The esterase activities in the Crawford strain were significantly higher than in the CSMA strain in most tissues except midgut and male genitalia, where the activities were similar. In both strains, isozyme a was dominant in the brain and fat body and isozymes c and d were more abundant in the midgut; but in addition to isozyme a, isozyme b was observed only in the Crawford strain. The α-naphthyl butyrate (α-NB) and β-naphthyl acetate (β-NA) esterase activities in the brain of both strains were completely inhibited by most inhibitors (DEF, 3,4-dichloroisocoumarine, paraoxon, pepstatin A, and propoxur). However, in the midgut tissue and contents, the activities and inhibition patterns of the α-NB and β-NA esterase were apparently different from the brain and between strains. The complete inhibition by paraoxon was observed regardless of the strain, substrate type, and body part for enzyme source. In esterase inhibition on native PAGE gels, paraoxon completely inhibited the activity of most esterases similar to the results from spectrophotometric assay. In addition, the esterase b was observed from the whole body homogenates of several German cockroach resistant strains on native PAGE analysis.

Esterase activity between the resistant Crawford and susceptible CSMA strains of German cockroach, Blattella germanica (L.), was compared with the substrates alpha- and beta-naphthyl acetate across sex and nymphal age classes. Esterase isozyme analysis with native polyacrylamide gel electrophoresis also was conducted to identify quantitative and qualitative differences between strains, sexes, and age classes. The Crawford strain was highly resistant to cypermethrin, propoxur, and permethrin with a resistant ratio (RR) of 17.26, 15.75, and 13.53, respectively, and mildly resistant to chlorpyrifos (RR 5.62). The alpha-NA and beta-NA esterase activities in the Crawford strain were significantly higher than those activities in the CSMA strain in both nymphal and adult stages. In the Crawford strain, the enzyme activity in nymphs was significantly higher than that in adults, but such differences were not observed in the CSMA strain. The mobile isozymes a and c stained more intensely than others in every developmental stage and sex of both strains but showed greater intensity in the Crawford strain. Another intensely stained isozyme b was observed only in the homogenates from the Crawford strain. The combination of isozyme b and the overproduced isozyme a and c in the Crawford strain seems to be responsible for the difference in total esterase activity between the CSMA and Crawford strains.

This article reports on the full genome sequence of Paenibacillus terrae HPL-003, which is a Gram-positive, endospore-forming, xylanase-producing bacterium isolated from soil found in forest residue on Gara Mountain. The strain HPL-003 contains 6,083,395 bp with a G+C content of 46.77 mol%, 2,633 protein-coding genes, and 117 structural RNAs.

Agrochemicals are compounds that selectively kill or arrest the growth of pests and weeds. They have played a significant role in agricultural production that provided for about 600 million people during the past 50 years. And also, the increasing world population seems to be a major driving force for the need to enhance the output of food production per area (Joseph, 2004). The agrochemical industry has been very successful in developing new herbicides. New chemicals with improved properties, especially providing significantly reduced application rates, and often new modes-of-action have been discovered, developed and launched for diverse crops. This success has positively influenced agriculture as a whole. However, in these days the introduction of new herbicides with either a new mode of action or novel chemical classes has lingered. After launch of sulcotrione, a HPPD herbicide at 1991, any herbicide with new mode-of-action has not been commercialized in Europe, while there were 10 new modes-of-action commercialized between 1970 and 1985 and five new ones between 1986 and 1991 (Schulte, 2004; Ruegg, 2007). Are there still opportunities for new herbicides, and what are the main search targets? Is there still an incentive to invest into herbicide research? Many factors adding complexity are agronomic, structural and technological changes, including the introduction of herbicidetolerant crops, and the high costs of development for new active ingredients, mainly due to increasing regulatory requirements. In the light of increasing weed resistance to widely used herbicides, securing diversity in agronomy as well as weed management is a key to efficient crop production in future. Further problems to be addressed are the expectations regarding weed shifts and/or the occurrence of (new) weed problems, due to the introduction of new weed species by global travel or international transport of goods. Will certain plants profit from climatic changes like global warming? The increase in the global population has already led to an intensification of crop production and this must continue in order to secure world food supply. In order to secure crop yields, chemical solutions for weed management will continue to be the preferable choice for the predictable future because apparent alternatives are not in sight. In order to support this objective, new herbicides, preferably with new modes-of-action, need to be discovered and developed. Until recently, the first step in agrochemical discovery was to take a collection of chemicals, apply each to a small population of representative pests, and assess their efficacy by visual inspection. This approach, sometimes impolitely called ‘spray and pray’, has its strengths

The KRICT PX1 gene (GB: FJ380951) consisting of 996bp encoding a protein of 332 amino acids (38.1kDa) from the recently isolated Paenibacillus sp. strain HPL-001 (KCTC11365BP) has been cloned and expressed in Escherichia coli. The xylanase KRICT PX1 showed high activity on birchwood xylan, and was active over a pH range of 5.0 to 11.0, with two optima at pH 5.5 and 9.5 at 50 degrees C with K(m) value of 5.35 and 3.23, respectively. The xylanase activity was not affected by most salts, such as NaCl, LiCl, KCl, NH(4)Cl, CaCl(2), MgCl(2), MnCl(2), and CsCl(2) at 1mM, but affected by CuSO(4), ZnSO(4), and FeCl(3). One mM of EDTA, 2-mercaptoethanol, and PMSF did not affect the xylanase activity. TLC analysis of the catalyzed products after reaction with birchwood xylan revealed that xylobiose was the major product with smaller amounts of xylotriose and xylose. A similarity analysis of the amino acids in KRICT PX1 resulted 72% identity with xylanase from Geobacillus stearothermophilus (GB: ZP_03040360), 70% identity with intracellular xylanase from an uncultured bacterium (GB: AAP51133), 68% identity with endo-1-4-xylanse from Paenibacillus sp. (GB: ZP_02847150). In addition, the amino acid alignment of KRICT PX1 with glycosyl hydralase (GH) family 10 xylanases revealed a high degree of homology in highly conserved regions including the catalytic sites, and this was confirmed through PROSITE scan. These results imply that KRICT PX1 is a new xylanase gene, and this alkaline xylanase belongs to GH family 10.

A series of fluorinated oxime compounds was designed and synthesized in order to probe the effect of fluorine substitution on reactivation of inhibited acetylcholinesterase (AChE) by organophosphorus agents. Permeability measurements, using the Parallel Artificial Membrane Permeation Assays (PAMPA) method, were employed to experimentally demonstrate that membrane permeabilities of the series of oximes increase in proportional to the increase in the number of fluorine atoms. Among the compounds explored in this study, the mono-fluorinated carbamoyl aldoxime 4b was the most potent reactivator for paraoxon-inhibited red blood cell (RBC) AChE.

Exposure to the organophosphorus nerve agents such as sarin, soman, cyclosarin, and VX causes acute intoxication by inhibiting acetylcholinesterase (AChE), where the serine residue of the active site can attack the phosphorous atom of the organophosphorus agents to form a strong P–O bond. The purpose of the present study was to evaluate new oxime antidotes to reactivate the inhibited AChE. We have designed and synthesized several new oximes, and have evaluated the substances that differ from the currently used oximes in linker between the two pyridinium rings. The potency of newly synthesized oximes was compared with two currently used AChE reactivators (2-PAM, HI-6). The reactivation potencies of the bis-pyridinium oximes connected with a (CH 2 ) n linker between the two quaternary nitrogen atoms were evaluated with housefly (HF) AChE inhibited by diisopropyl fluorophosphates (DFP) and by paraoxon. The bis-pyridinium oximes showed stronger activity compared with mono-pyridinium oxime, and the magnitude of reactivation potency depended on the length of the methylene linker. The potency order was (CH 2 ) 2 ) 2 2 ) 3 > (CH 2 ) 4 > (CH 2 ) 7 . A (CH 2 ) 3 linker was optimal in HF AChE inhibited by either DFP or paraoxon. Thus, bis-pyridinium oxime 5 which has (CH 2 ) 3 linker showed the highest activity in this series of compounds. Interestingly, 5 was not as active as 2-PAM, showing that the position of the oxime group on the pyridinium ring is also very important for the reactivation potency.

The judicious utilization of solar light for the asymmetric synthesis of optically active compounds by imitating natural photosynthesis introduces a new concept that harnesses this renewable energy in vitro for ultimate transformation into chiral chemical bonds. Herein, we present a comprehensive description of such a biomimetic endeavor towards the design and construction of an asymmetric artificial photosynthesis system that comprises an efficient method of nicotinamide cofactor (NADPH) regeneration under visible light employing a graphene-based light harvesting photocatalyst and its subsequent utilization in an enzyme-catalyzed asymmetric reduction of prochiral ketones to expediently furnish the corresponding chiral secondary alcohols. A detailed optimization study revealed a major dependency of the reaction outcome on the amount of cofactor, photocatalyst and enzyme used, as well as the mode of their addition. A series of structurally diverse ketones bearing an array of (hetero)aryl/alkyl substituents proved to be highly suitable to our photocatalytic–biocatalytic cascade approach, providing (R/S)-1-(hetero)aryl/alkylethanols in excellent enantioselectivities (ee ∼ 95–>99.9%) under mild and environmentally benign conditions. To the best of our knowledge, the synthesis of these enantiopure alcohols employing a visible-light-driven nicotinamide cofactor regeneration strategy has been reported for the first time. Such enantioenriched alcohols act as versatile chiral building blocks for the synthesis of compounds having industrial and pharmaceutical relevance. In addition, this solar-to-chiral chemicals prototype appears advantageous from ecological and economical perspectives. We describe mechanistic pathways to demonstrate how the present catalytic synthesis protocol functions through perfect orchestration between visible-light-driven photocatalysis and biocatalysis to be successively applied in inducing asymmetry in an achiral molecule for the ultimate goal of solar energy utilization in the synthesis of valuable chiral fine chemicals. This work highlights the potential advantages of a bioinspired system to the pertinence of solar energy in asymmetric transformations leading to enantioenriched alcohol precursors, and thus opens up a new field of research that might emerge as an important breakthrough with promising implications towards generating a sustainable and non-fossil/non-nuclear energy future.

The effect of topically applied chlorpyrifos on acetylcholinesterase and other esterases in heads and decapitated bodies of CSMA and Crawford German cockroaches was examined with spectrophotometric enzyme assay and native polyacrylamide gel electrophoresis. The toxicity of chlorpyrifos was greatly reduced in decapitated CSMA male cockroaches with LD50 value 17.1-fold higher than that of normal CSMA cockroaches. Acetylcholinesterase activity from heads was significantly higher in the Crawford compared with the CSMA strain and did not change until 24 h after chlorpyrifos in vivo treatment in both strains. The p-nitrophenyl butyrate (NPB) esterase activities from both heads and decapitated bodies of the resistant Crawford strain were significantly greater than the susceptible CSMA strain. The p-NPB esterase activity was significantly inhibited by chlorpyrifos in vivo treatment, and total p-NPB esterase activity was significantly reduced in decapitated bodies compared with heads of both strains. Native polyacrylamide gel electrophoresis (PAGE) analysis of extracts solubilized with Triton X-100 from heads and decapitated bodies revealed five major esterase bands and an acetylcholinesterase (AChE) band with a high capability of hydrolyzing alpha-naphthyl butyrate and acetylthiocholine, respectively. In the heads of susceptible CSMA male cockroaches, the activity of mobile isozymes d1 and d2 was completely inhibited at 24 h after chlorpyrifos application, and isozyme e was partially inhibited. In contrast, isozymes c1 and c2 from the decapitated bodies of CSMA cockroaches were mostly affected at 24 h after the topical application of chlorpyrifos. The activities of acetylcholinesterase and esterase isozymes a and b from the decapitated body remained uninhibited in both strains. Inhibition of isozymes d1 and d2 seems to be more important in chlorpyrifos intoxication than acetylcholinesterase.

The utilization of CO2 for production of solar fuels/chemicals is gaining increasing importance due to worldwide fossil-fuel shortage and global warming. As a means to achieve this, we herein report on the synthesis and development of a graphene-based visible light active photocatalyst (CCG–BODIPY) which is chemically converted graphene (CCG) covalently bonded to a light harvesting BODIPY molecule (1-picolylamine-2-aminophenyl-3-oxy-phenyl-4,4′-difluoro-1,3,5,7-tetramethyl-2,6-diethyl-4-bora-3a,4a-diaza-s-indacene-triazine). The photocatalyst-biocatalyst coupled system developed using CCG–BODIPY as photocatalyst functions in a highly efficient manner, leading to high NADH regeneration (54.02 ± 0.61%), followed by its consumption in exclusive formic acid production (144.2 ± 1.8 μmol) from CO2. The present research endeavour highlights the development and application of a graphene based photocatalyst for direct solar fuel formation from carbon dioxide.

Eight structurally different acetylcholinesterase reactivators derived from currently commercially available oximes were tested for their potency to reactivate acetylcholinesterase inhibited by pesticide paraoxon (P) and DFP (D). Housefly AChE (F) and bovine red blood cell AChE (B) were used as the source of the cholinesterases. Ellman's method was taken to examine cholinesterases activity. The results show that four AChE reactivators are potent AChE reactivators, able to reach reactivation potency of more than 30% in all cases - PF, PB, DF and DB. Their reactivation potency was comparable with that of pralidoxime and even higher compared with that of HI-6, standard AChE reactivators currently available on the market.