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This work deals with the dielectric properties of silane treated pineapple leaf fiber and kenaf fiber reinforced phenolic hybrid composites. The aim of the present paper is to investigate the effect of silane treatment on the pineapple leaf fiber–kenaf fiber/matrix interfacial adhesion using the dielectric relaxation spectroscopy in the frequency range from 0.1 Hz to 1 MHz and temperature range from 50 to 180℃. Our hybrid composites were fabricated by hand lay-up method at 50% total fiber loading. All the results obtained were discussed in terms of dynamic molecular and interfacial process. Two interfacial polarizations identified as the Maxwell–Wagner–Sillars effect are observed. We note that silane treatment improved the interfacial adhesion between pineapple leaf fiber/kenaf fiber and phenolic resin and it will help to develop high performance kenaf fiber/pineapple leaf fiber reinforced polymer composites for industrial applications. In fact, as known, the silane treatment developed hydrophobic nature in pineapple leaf fiber and kenaf fiber which is very positive for fiber/matrix compatibility.

Numerical studies of pulverized coal swirl combustion in oxy-fuel atmosphere are carried out. Thereby two issues are especially addressed: (1) how LES and RANS impact differently the predictions of combustion properties even though, in both approaches, the same kinetic rates are used to represent the coal combustion processes; (2) how the numerical multiphase treatments may affect the prediction of micro-process interaction as well as the range in which these processes are not negligible. For that purpose a methodology is developed based on an Eulerian-Lagrangian oxy-coal combustion module which is designed relying on the state of the art models as implemented in the commercial code ANSYS Fluent 17. This especially includes three kinetic rates for the description of coal combustion, namely coal devolatilization, volatile combustion and char combustion. Based on an appropriate Stokes number consideration, a full two-way inter-phase coupling has been numerically adopted. To assess the prediction capability of the overall model, a new set of experimental data from a 60 kW(th) oxy-coal test facility is employed. First, the model validation is ensured by comparison of results in terms of flow field and products from volatile and char combustion. Then, an analysis is performed to elucidate how the two-phase turbulence modeling impacts the thermal flow predictions along with the evolution of multiphase oxy-coal combustion properties. Finally, it is demonstrated how the numerical multiphase treatments affect the prediction of micro process interaction in terms of coal devolatilization, coal particle distribution due to turbulent particle dispersion, and of gaseous heat release as well as char burnout. The range in which these interphase processes (subgrid scale particle dispersion) are not negligible is also pointed out in terms of subgrid scale Stokes number. (C) 2017 Elsevier Ltd. All rights reserved.

To assess the health risk posed by flumethrin residues in beeswax to honeybees and honey consumers, 124 wax samples randomly distributed in Belgium were analysed for flumethrin residues using liquid chromatography/tandem mass spectrometry. The risk posed by flumethrin residues in beeswax to honeybee health was assessed through the calculation of a non-pondered and a pondered Hazard Quotient by the prevalence rate of flumethrin considering an oral or topical exposure. No statistical difference was found when comparing both the average flumethrin residues concentrations and contact and oral pondered hazard quotients between apiaries with lower and equal or higher than 10% of colony loss. Flumethrin residues estimated daily intake by Belgian consumers through honey and wax ingestion was estimated via a deterministic (worst-case scenario) and a probabilistic approach. The probabilistic approach was not possible for beeswax consumption due to the lack of individual consumption data. The highest estimated exposure was

We prepared a series of substituted aminocyanopyrroles and another of aminocynaothiophenes. We describe an efficient new one-step synthetic strategy via the condensation of an alkyl sarcosinate and ethoxymethylenemalononitrile, through a Gewald-like reaction. The UV–visible absorption and steady-state and time resolved fluorescence properties of some representative compounds, as well as their acid-base behavior, is also presented. The compounds might be useful for medicinal applications and as bioimaging probes.

A detailed numerical simulation of a cold flow without spray injection of Marchoine et al. (2009) configuration are carried out. The introduced swirling air were simulated with Large Eddy Simulation (LES) and the Reynolds-averaged Navier–Stokes equations (RANS). Focus is put on the turbulent kinetic energy level on the spark location. Simulations results are plotted against experimental data.

How proteins are protected from stress-induced aggregation is a crucial question in biology and a long-standing mystery. While a long series of landmark studies have provided important contributions to our current understanding of the proteostasis network, key fundamental questions remain unsolved. In this study, we show that the intrinsic features of the chaperedoxin CnoX, a folding factor that combines chaperone and redox protective function, have been tailored during evolution to fit to the specific needs of their host. Whereas Escherichia coli CnoX needs to be activated by bleach, a powerful oxidant produced by our immune system, its counterpart in Caulobacter crescentus, a bacterium living in bleach-free environments, is a constitutive chaperone. In addition, the redox properties of E. coli and C. crescentus CnoX also differ to best contribute to their respective cellular redox homeostasis. This work demonstrates how proteins from the same family have evolved to meet the needs of their hosts., Hypochlorous acid (bleach), an oxidizing compound produced by neutrophils, turns the Escherichia coli chaperedoxin CnoX into a powerful holdase protecting its substrates from bleach-induced aggregation. CnoX is well conserved in bacteria, even in non-infectious species unlikely to encounter this oxidant, muddying the role of CnoX in these organisms. Here, we found that CnoX in the non-pathogenic aquatic bacterium Caulobacter crescentus functions as a holdase that efficiently protects 50 proteins from heat-induced aggregation. Remarkably, the chaperone activity of Caulobacter CnoX is constitutive. Like E. coli CnoX, Caulobacter CnoX transfers its substrates to DnaK/J/GrpE and GroEL/ES for refolding, indicating conservation of cooperation with GroEL/ES. Interestingly, Caulobacter CnoX exhibits thioredoxin oxidoreductase activity, by which it controls the redox state of 90 proteins. This function, which E. coli CnoX lacks, is likely welcome in a bacterium poorly equipped with antioxidant defenses. Thus, the redox and chaperone properties of CnoX chaperedoxins were fine-tuned during evolution to adapt these proteins to the specific needs of each species.

International audience; The reactive species of oxygen and chlorine damage cellular components, potentially leading to cell death. In proteins, the sulfur-containing amino acid methionine is converted to methionine sulfoxide, which can cause a loss of biological activity. To rescue proteins with methionine sulfoxide residues, living cells express methionine sulfoxide reductases (Msrs) in most subcellular compartments, including the cytosol, mitochondria and chloroplasts(1-3). Here we report the identification of an enzymatic system, MsrPQ, repairing proteins containing methionine sulfoxide in the bacterial cell envelope, a compartment particularly exposed to the reactive species of oxygen and chlorine generated by the host defence mechanisms. MsrP, a molybdo-enzyme, and MsrQ, a haem-binding membrane protein, are widely conserved throughout Gram-negative bacteria, including major human pathogens. MsrPQ synthesis is induced by hypochlorous acid, a powerful antimicrobial released by neutrophils. Consistently, MsrPQ is essential for the maintenance of envelope integrity under bleach stress, rescuing a wide series of structurally unrelated periplasmic proteins from methionine oxidation, including the primary periplasmic chaperone SurA. For this activity, MsrPQ uses electrons from the respiratory chain, which represents a novel mechanism to import reducing equivalents into the bacterial cell envelope. A remarkable feature of MsrPQ is its capacity to reduce both rectus (R-) and sinister (S-) diastereoisomers of methionine sulfoxide, making this oxidoreductase complex functionally different from previously identified Msrs. The discovery that a large class of bacteria contain a single, non-stereospecific enzymatic complex fully protecting methionine residues from oxidation should prompt a search for similar systems in eukaryotic subcellular oxidizing compartments, including the endoplasmic reticulum.

The crystallization of (C 11 N 4 H 10 ) 2 ·H 2 O (I) and (C 11 N 4 H 10 ) 4 ·H 2 O (II) is made by slow evaporation from aqueous solutions. The structures of these compounds have been solved and refined by single-crystal X-ray diffraction data. The compound (I) is centrosymmetric (space group C2/c) with lattice parameters: a = 14.118 (2) A, b = 7.399 (1) A, c = 21.982 (3) A and β = 107.80 (1)°. The compound (II) crystallizes in the same space group (C2/c) with lattice parameters: a = 28.976 (2) A, b = 7.593 (2) A, c = 21.724 (2) A and β = 115.819 (2)°. The cohesion in both structures is provided by two types of bonds: hydrogen bonds O H⋯N and N H⋯O involving water molecules and organic molecules, and Van der Waals bonds for the connection between the organic molecules. The IR spectra shows an enlargement of the band between 3300 and 2800 cm −1 , due to the presence of water molecules and the overlap of vibration modes ν (O H) and ν (C H, N H). The optical band gap is determined to be 4.07 eV by UV–Vis–T90+ absorption spectra, which revealed the nature of insulator.

In order to assess bee and human exposure to residues of glyphosate-based herbicide (GBH) and its main degradation products aminomethylphosphonic acid (AMPA) and to characterise the risk posed by these substances, we analysed 3 different bee matrices; beebread (N = 81), wax (N = 100) and 10-paired samples of wax/honey collected in 2016/2017 from 379 Belgian apiaries. A high-performance liquid chromatography-electrospray ionisation tandem mass spectrometry (HPLC-ESI-MS-MS) was used as analytical method. Limit of quantification and detection (LOQ and LOD) for GBH residues and AMPA in the 3 matrices was respectively of 10 ng g−1 and 1 ng g−1. In beebread, 81.5% of the samples showed a residue concentration > LOQ and 9.9% of the samples a residue concentration LOQ versus 81.5% >LOQ). The maximum GBH residues and AMPA concentration found in beebread (respectively 700 ng g−1 and 250 ng g−1) led to sub-lethal exposure to bees. The Hazard Quotient (HQ) for beebread and beeswax (7 and 3.2, respectively) were far below the “safety” oral and contact thresholds for bees. For human health, the highest exposure to GBH residues in pollen corresponded to 0.312% and 0.187% of the ADI and of the ARfD respectively and, to 0.002% and to 0.001% for beeswax. No transfer of glyphosate from wax to honey was detected. Considering our results and the available regulatory data on the glyphosate molecule considered solely, not including the adjuvants in GBH formulation, the consumption of these three contaminated matrices would not be a food safety issue. Nonetheless, caution should be taken in the interpretation of the results as new studies indicate possible glyphosate/GBH residues toxicity below regulatory limits and at chronic sub-lethal doses.

Several new pyrazolopyrimidine compounds were achieved from aminocyanopyarazole 1. The starting material 1 was initially coupled with orthoester at refluxed with various primary amines, ammonia, hydrazines and hydroxylamine to furnish a series of pyrazolo[3,4-d]pyrimidines. The reaction of imidate 2a-b with hydrazide derivatives led to the formation of pyrazolo[3,4-d][1,2,4]triazolo[4,3-c]pyrimidines. Some of the synthesized compounds 3a and 4c were evaluated for their anti-inflammatory, antipyretic and nociceptive activities. We start by studing the toxicity of these two molecules by measuring the corresponding DL50. The DL50 of 3a and 4c are estimated to 1333.2mg / kg and 1593.5mg / kg respectively. Pharmacological evaluation showed that compounds 3a and 4c at doses (5.5-22.2 mg / Kg, i.p) exhibited anti-inflammatory activities compared to Ibuprofen (150 mg / Kg, i.p), used as a refer ence drug. Further, our study showed that the injection of derived pyrazolopyrimidines on hyperthermic animal leads to a decrease in temperature after 1 hours of treatment compared to paracetamol used as reference. In addition, the injection of derived pyrazolopyrimidines at different doses contains a potent nociceptive activity. This effect is dose-dependent compared to aspirin.

We report the synthesis of new anti-inflammatory 1,7-dihydropyrazolo[3′,4′:4,5]pyrimido[1,6-a]pyrimidine 5 from aminocyanopyrazole. All compounds were characterized by physical, chemical and spectral studies. Preliminary pharmacological evaluation of the resulting products showed that compounds 5a, b, f (50–100 mg/kg, i.p) are active anti-inflammatory agents in carrageenan-induced rat paw oedema assay, and their effects are comparable to that of acetylsalicylic–lysine (300 mg/kg, i.p.), used as a reference drug. The nature of substituent (Y, R3) had a pronounced effect on the anti-inflammatory activity. Studies of structure–activity relationships have led to selection of compound ethyl-3,5-dimethyl-7-imino-N1-phenyl-1,7-dihydropyrazolo[3′,4′:4,5]pyrimido[1,6-a]pyrimidine-6-carboxylate, 5f which exhibited the most potent anti-inflammatory activity. In addition, the compounds 5a, b, f showed a significant gastroprotective effect against HCl/EtOH-induced gastric ulcer.

A three-component condensation reaction between aminopyrazolo[3,4- d ]pyrimidine, an aldehyde, and an isocyanide catalyzed by scandium triflate yields a series of heterocyclic derivatives of imidazo[1,2- c ]pyrazolo[3,4- d ]pyrimidine in good yields, exhibiting interesting fluorescent properties.

Acidic hydrolysis of Ugi adducts formed from α-hydrazonocarboxylic acids and aminoacetaldehyde dimethyl acetal leads to the fragmentation of aminoacetaldehyde residues with final formation of pyrazoles. An aldol-type reaction of the hydrazone is proposed as the key step of the cascade.

Bacterial pathogens often deliver effectors into host cells using type 3 secretion systems (T3SS), the extremity of which forms a translocon that perforates the host plasma membrane. The T3SS encoded by Salmonella pathogenicity island 1 (SPI-1) is genetically associated with an acyl carrier protein, IacP, whose role has remained enigmatic. In this study, using tandem affinity purification, we identify a direct protein-protein interaction between IacP and the translocon protein SipB. We show, by mass spectrometry and radiolabelling, that SipB is acylated, which provides evidence for a modification of the translocon that has not been described before. A unique and conserved cysteine residue of SipB is identified as crucial for this modification. Although acylation of SipB was not essential to virulence, we show that this posttranslational modification promoted SipB insertion into host-cell membranes and pore-forming activity linked to the SPI-1 T3SS. Cooccurrence of acyl carrier and translocon proteins in several γ- and β-proteobacteria suggests that acylation of the translocon is conserved in these other pathogenic bacteria. These results also indicate that acyl carrier proteins, known for their involvement in metabolic pathways, have also evolved as cofactors of new bacterial protein lipidation pathways., Author Summary Acyl carrier proteins are small ubiquitous proteins involved in the synthesis of hydrocarbon based molecules. Notably, they are essential for the synthesis of fatty acids, which are the precursors of membrane phospholipids. They can also be involved in secondary metabolism, for example for the synthesis of molecules with antibacterial properties. Although acyl carrier proteins are widespread, the specific role of each individual protein seems comparatively poorly explored. In this study, we investigate the role of an acyl carrier protein genetically associated with a type 3 secretion system (T3SS). Many Gram-negative bacterial pathogens use T3SS to deliver effectors directly into the cytoplasm of eukaryotic host cells and to subvert host cellular pathways. For this purpose, the translocon, which is the terminal part of T3SS, forms a pore inserted into the host-cell membrane. Here we show that the acyl carrier protein associated with the T3SS has specialized to allow acylation of the translocon. The novel posttranslational modification of the translocon that we describe optimizes insertion into the host-cell membrane and pore-forming activity. This mechanism is likely to be conserved in other pathogenic bacteria given the conserved genetic association between T3SS and acyl carrier protein in several bacteria.

(R)-(E)-6,7-Epoxyocimene, the major constituent of the essential oil from Plectranthus tenuicaulis, as well as the racemic (Z)-isomer previously synthesized from commercial (Z)-beta-ocimene were used as starting material for the synthesis of fragrant derivatives. Among the 14 compounds obtained from these precursors (alcohols, diols, diepoxy, sulfur and carbonyl derivatives), four were described for the first time and three were enantiomerically pure. All compounds were fully characterized by one- and two-dimensional nuclear magnetic resonance analysis as well as by gas chromatography and mass spectroscopy (electron ionization). Additionally, their odour properties were evaluated

A detergent stable alkaline serine-protease from Bacillus licheniformis MP1 was purified in three steps: ultrafiltration using a 10 kDa cut-off membrane, Sephadex G-100 gel filtration, and Mono Q-Sepharose ion exchange chromatography with a 3.9-fold increase in specific activity and 48.2% recovery. The N-terminal amino acid sequence of the first 14 amino acids of the purified enzyme was AQTVPYGIPLIKAD. The molecular weight of the purified enzyme was estimated to be 30 kDa. The optimum pH and temperature of the purified protease were 10.0 and 70 °C, respectively, using casein as a substrate. It showed high stability towards alkaline pH, non-ionic surfactants and was relatively stable towards SDS. Additionally, the crude enzyme showed higher stability and compatibility with various laundry detergents from Tunisian market, and the addition of MP1 proteolytic preparation (40 U/ml) to wash solution, enhance bloodstain elimination. In addition, when used in shrimp waste deproteinization at E/S = 20 U/mg protein ratio, MP1 proteolytic preparation leads to 75% deproteinization. The aprMP1 gene, encoding the alkaline protease from B. licheniformis MP1, was isolated, and its DNA sequence was determined. The deduced amino acid sequence of the preproenzyme showed high homology with many other known serine protease genes, and some differences that characterize it.

A new and convenient synthesis of 2-acetyl-1-pyrroline (2AP), a potent flavor compound in rice, and its ring-deuterated analog, 2-acetyl-1-d2-pyrroline (2AP-d2), was reported. A stable isotope dilution assay (SIDA), involving headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-positive chemical ionization-ion trap-tandem mass spectrometry (GC-PCI-IT-MS-MS), was developed for 2AP quantification. A divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was used for HS-SPME procedure and parameters affecting analytes recovery, such as extraction time and temperature, pH and salt, were studied. The repeatability of the method (n=10) expressed as relative standard deviation (RSD) was 11.6%. A good linearity was observed from 5.9 to 779ng of 2AP (r2=0.9989). Limits of detection (LOD) and quantification (LOQ) for 2AP were 0.1 and 0.4ngg-1 of rice, respectively. The recovery of spiked 2AP from rice matrix was almost complete. The developed method was applied to the quantification of 2AP in aerial parts and grains of scented and non-scented rice cultivars. © 2010 Elsevier B.V. This research was funded by the Office National Interprofessionnel des Grandes Cultures (ONIGC) as a part of the “Plan de Relance de la Filiere Riz Camarguaise” project. We thank the Centre Français du Riz (CFR, Arles, France) for providing the rice samples. We also thank Languedoc Roussillon region and Cirad for supporting the doctoral fellowship of the author I. Maraval.

This study was conducted to evaluate the effect of camel milk in alloxan-induced diabetic dogs and to follow this effect at three doses of milk. Firstly, three groups of dogs were used: two groups composed each of four diabetic dogs and receiving raw camel milk (treatment 1) or cow milk (treatment 2), and four healthy dogs getting raw camel milk (treatment 3) were used as control. Each animal was treated with 500 ml of milk daily. Secondly, we compared the effects of three amounts of camel milk: 100 ml, 250 ml and 500 ml to treat the diabetic dogs. After week 3, the dogs treated with camel milk showed a statistically significant decrease in blood glucose (from 10.88 +/- 0.55 to 6.22 +/- 0.5 mmol/l) and total protein concentrations (from 78.16 +/- 2.61 g/l to 63.63 +/- 4.43 g/l). For cholesterol levels, there was a decrease from week 2 (from 6.17 +/- 0.5 mmol/l to 4.79 +/- 0.5 mmol/l). There were no significant difference in blood glucose, cholesterol or total protein concentrations in dogs drinking 250 and 500 ml of camel milk. The dogs treated with 100 ml of camel milk did not show any significant decrease in blood glucose levels, and cholesterol and total protein concentrations. The investigation was not limited to the improvement in glycemic balance, lipids and proteins control in diabetic dogs getting camel milk, but we also noted a stability of this state after the dogs stopped to drink milk. This effect depended on the quantity of camel milk used to treat diabetic dogs.

A novel fibrinolytic enzyme, subtilisin BSF1, from a newly isolated Bacillus subtilis A26 was purified, characterized and the gene was isolated and sequenced. The subtilisin BSF1 was purified to homogeneity by five-step procedure with a 4.97-fold increase in specific activity and 6.28% recovery. The molecular weight of the purified enzyme was estimated to be 28 kDa by SDS-PAGE and gel filtration. The purified enzyme exhibited high fibrinolytic activity on fibrin agar plates. Interestingly, the enzyme was highly active over a wide range of pH from 7.0 to 12.0, with an optimum at pH 9.0. The relative activities at pH 10.0 and 11.0 were 97.8% and 85.2% of that at pH 9.0. The optimum temperature for enzyme activity was 60 °C. The activity of subtilisin BSF1 was totally lost in the presence of PMSF, suggesting that the purified enzyme is a serine protease. The N-terminal amino acid sequence of the first 11 amino acids (aa) of the purified fibrinolytic enzyme was AQSVPYGISQI. The bsf1 gene encoding the subtilisin BSF1 was isolated and its DNA sequence was determined. The bsf1 gene consisted of 1146 bp encoding a pre-pro-protein of 381 amino acids organized into a signal peptide (29 aa), a pro-peptide (77 aa) and a mature domain (275 aa). The deduced amino acids sequence of the mature enzyme (BSF1) differs from those of nattokinase from B. subtilis natto and subtilisin DFE from Bacillus amyloliquefaciens DC-4 by 5 and 39 amino acids, respectively.

A fibrinolytic enzyme producing bacterium was isolated and identified as Bacillus subtilis A26 on the basis of the 16S rRNA gene sequence. The fibrin zymography analysis reveals the presence of at least three fibrinolytic enzymes. The crude enzyme exhibited maximal activity at 60 °C and pH 8.0. Medium composition and culture conditions for the enzyme production by B. subtilis A26 were optimized using two statistical methods. The Plackett–Burman statistical design was applied to find the key ingredients and conditions for the best yield of enzyme production. Five significant variables (hulled grain of wheat, casein peptone, NaCl, CaCl2, and initial pH) were selected for the optimization studies. The response surface methodological approach was used to determine the optimal concentrations and conditions. The optimized medium contained 40.0 g·L–1hulled grain of wheat, 3.53 g·L–1casein peptone, 4.0 g·L–1CaCl2, 3.99 g·L–1NaCl, 0.01 g·L–1MgSO4, and 0.01 g·L–1KH2PO4, pH 7.78. The medium optimization resulted in a 4.2-fold increased level of fibrinolytic production (269.36 U·mL–1) compared with that obtained with the initial medium (63.45 U·mL–1). A successful and significant improvement in the production of protease by the A26 strain was accomplished using inexpensive carbon substrate (hulled grain of wheat), allowing a significant reduction in the cost of medium constituents.

Two detergent stable alkaline serine-proteases (BM1 and BM2) from Bacillus mojavensis A21 were purified. The molecular weights of BM1 and BM2 enzymes determined by SDS–PAGE were approximately 29,000 Da and 15,500 Da, respectively. The optimum pH values of BM1 and BM2 proteases were shown to be 8.0–10.0 and 10.0, respectively. Both enzymes exhibited maximal activity at 60 °C, using casein as a substrate. The N-terminal amino acid sequences of BM1 and BM2 proteases were AQSVPYGISQIKA and AIPDQAATTLL , respectively. Both proteases showed high stability towards non-ionic surfactants. The enzymes were found to be relatively stable towards oxidizing agents. In addition, both enzymes showed excellent stability and compatibility with a wide range of commercial liquid and solid detergents. These properties and the high activity in high alkaline pH make these proteases an ideal choice for application in detergent formulations.

An extracellular calcium-dependent protease from a newly isolated Bacillus cereus SV1 was purified, characterized and the gene was isolated and sequenced. The enzyme was purified to homogeneity by ultrafiltration, Sephacryl S-200 gel filtration, DEAE-cellulose ion exchange chromatography, then by a second gel filtration on Sephacryl S-200 with a six-fold increase in specific activity and 28% recovery. The production of SV1 protease was observed in media containing CaCl2 but not in media containing BaCl2, MgCl2, MnCl2 and ZnCl2. The molecular weight of the enzyme was estimated to be 35.5 kDa on SDS-PAGE. The enzyme exhibited maximal activity at pH 8.0 and 55 8C, without the presence of CaCl2. Thermoactivity and thermostability of the enzyme were significantly increased in the presence of Ca 2+ . The activity was totally lost in the presence of EDTA, suggesting that the purified enzyme is a metalloprotease. The nprC1 gene, which encodes the calcium-dependent protease from B. cereus SV1, was isolated and its DNA sequence was determined. The nprC1 gene consists of 1701 bp encoding a preproprotein of 566 amino acids with three distinct domains: a signal peptide (27 amino acids), a propeptide (222 amino acids) and a mature enzyme (317 amino acids). The nprC1 gene coding sequence presents only 91% and 89% identity to those encoding neutral protease from B. cereus ATCC 14579 and bacillolysin from B. cereus DSM 3101, respectively. The deduced amino acid sequence of the mature protease (NprC1) differs from those of DSM 3101 and ATCC 14579 with 16 and 17 amino acids, respectively, suggesting that the nprC1 is a new protease gene. # 2008 Elsevier Ltd. All rights reserved.

A bacterium producing thermostable alkaline serine-protease was isolated from an activated sludge reactor treating fishery wastewaters and was identified as Bacillus licheniformis NH1. The most appropriate medium for the growth and protease production is composed of (g/l): casein 5; yeast extract 2–4, KCl 1.5, K2HPO4 0.5 and KH2PO4 0.5. The crude extracellular protease produced by the isolate had optimal activity at 65–70 and 70 °C in the absence or presence of 2 mM CaCl2, respectively. The thermostability of the enzyme was considerably enhanced in the presence of Ca2+ at temperature values above 50 °C. The enzyme retained 62 and 100% of its initial activity after heating for 60 min at 60 °C, in the absence or presence of 2 mM CaCl2, respectively. The protease was highly active and stable from pH 7.0 to 12.0, with an optimum at pH 10.0–11.0. The activity was totally lost in the presence of PMSF, suggesting that the preparation contains serine-protease(s). Furthermore, the enzyme showed excellent stability and compatibility with some commercial laundry detergents. The enzyme retained more than 93% of its initial activity after preincubation 60 min at 40 °C in the presence of 7 mg/ml of Dixan, Axion and New Dex. The aprN gene encoding the alkaline serine-protease was isolated and its DNA sequence was determined. The aprN gene consisted of 1137 bp encoding a protein of 379 amino acids organized into a signal peptide (29 amino acids), a pro-protein (76 amino acids), and mature enzyme (274 amino acids). The deduced amino acid sequence indicates only three amino acid differences between NH1 enzyme and subtilisin Carlsberg from Bacillus licheniformis NCIMB 6816.

This new cyclization cascade reaction gives at first Ugi hydrazones, which can be easily converted to the corresponding pyrazoles via a formal [3 + 2]-cycloaddition.

Two simple protocols using Sc(OTf)3 as the catalyst are presented for the synthesis of the title-compounds via three component condensation of pyrazolopyrimidines, aldehydes, and isocyanides.

This research was conducted to evaluate the antidiabetic effect of camel milk in alloxan-induced-diabetic dogs. Diabetes was induced by intravenous injection of alloxan monohydrate (65 mg/kg bodyweight). The effects of camel milk on diabetic dogs were investigated by observing changes in the glycometabolic index (fasting blood glucose,intravenous glucose tolerance test (IGTT)) test, the lipometabolic index (triglyceride, cholesterol), total proteins and in the degree of injury of β-cells in the pancreatic islets. A significant decrease in fasting plasma glucose, cholesterol and total proteins in blood sample and an improvement on the animal clinical state (increase of body weight, normal activity) was observed. Camel milk also induces renewal of pancreatic β-cells. A comparison was made between the effect of camel milk and cow milk. Treatment with cow milk does not have any benefit effect on alloxan-induced diabetic dogs. Key words: Alloxan, diabetes, dogs, antidiabetic effect, camel milk, β-cells.

Camel milk is recognized by nomads for its therapeutic effect to treat several diseases especially diabetes. This study was conducted to evaluate the effect of raw, pasteurized and boiled camel milk on Alloxan- induced diabetic dogs. Firstly, three groups of dogs were used: group 1 and group 2 composed each of 4 diabetic dogs and receiving respectively 250 ml of raw camel milk/ dog/ day or 250 ml of raw cow milk/ dog/ day. Group 3 consisted of 4 healthy dogs getting raw camel milk were used as control. Secondly, we tested the effect of heat treatment on the anti-diabetic property of camel milk. Two other groups composed of 4 diabetics dogs each and treated with 250 ml of pasteurized camel milk/ dog/ day (group 4) or with 250 ml of boiled camel milk/ dog/ day (group 5).

The current increase in amount of shrimp wastes produced by the shrimp industry has led to the need in finding new methods for shrimp wastes disposal. In this study, an extracellular organic solvent- and oxidant-stable metalloprotease was produced by Bacillus cereus SV1. Maximum protease activity (5,900 U/mL) was obtained when the strain was grown in medium containing 40 g/L shrimp wastes powder as a sole carbon source. The optimum pH, optimum temperature, pH stability, and thermal stability of the crude enzyme preparation were pH 8.0, 60 degrees C, pH 6-9.5, and55 degrees C, respectively. The crude protease was extremely stable toward several organic solvents. No loss of activity was observed even after 60 days of incubation at 30 degrees C in the presence of 50% (v/v) dimethyl sulfoxide and ethyl ether; the enzyme retained more than 70% of its original activity in the presence of ethanol and N,N-dimethylformamide. The protease showed high stability toward anionic (SDS) and non-ionic (Tween 80, Tween 20, and Triton X-100) surfactants. Interestingly, the activity of the enzyme was significantly enhanced by oxidizing agents. In addition, the enzyme showed excellent compatibility with some commercial liquid detergents. The protease of B. cereus SV1, produced under the optimal culture conditions, was tested for shrimp waste deproteinization in the preparation of chitin. The protein removal with a ratio E/S of 20 was about 88%. The novelties of the SV1 protease include its high stability to organic solvents and surfactants. These unique properties make it an ideal choice for application in detergent formulations and enzymatic peptide synthesis. In addition, the enzyme may find potential applications in the deproteinization of shrimp wastes to produce chitin.

A protease-producing bacterium was isolated and identified as Pseudomonas aeruginosa MN7. The strain was found to produce proteases when it was grown in media containing only shrimp waste powder (SWP), indicating that it can obtain its carbon, nitrogen, and salts requirements directly from shrimp waste. The use of 60 g/l SWP resulted in a high protease production. Elastase, the major protease produced by P. aeruginosa MN7, was purified from the culture supernatant to homogeneity using acetone precipitation, Sephadex G-75 gel filtration, and ultrafiltration using a 10-kDa cut-off membrane, with a 5.2-fold increase in specific activity and 38.4% recovery. The molecular weight of the purified elastase was estimated to be 34 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration. The optimum temperature and pH for protease activity were 60 degrees C and 8.0, respectively. The activity of the enzyme was totally lost in the presence of ethylene glycol tetraacetic acid, suggesting that the purified enzyme is a metalloprotease. The purified enzyme was highly stable in the presence of organic solvents, retaining 100% of its initial activity after 60 days of incubation at 30 degrees C in the presence of dimethyl sulfoxide and methanol. The lasB gene, encoding the MN7 elastase, was isolated and its DNA sequence was determined.

The essential oils obtained by hydrodistillation of pieces of dead trunks of Callitris sulcata (Parlatore) Schlechter and Callitris neocaledonica Dummer were investigated by gas chromatography, mass spectrometry and NMR spectroscopy. Analyses evidenced the presence of rare natural compounds: both essential oils are exclusively sesquiterpenic with nevertheless remarkable difference: C. sulcata essential oil was dominated by β-barbatene and thujopsene while C. neocaledonica was characterized by high levels of guaiane- and eudesmane-type structures (eudesmols, guaiol and related components). The biochemical correlations between the major components of each species are discussed and the relationship between the two species is commented.

[Bis(dimethylgermyl)alkane]iron tetracarbonyls, Me 2 Ge(CH 2 ) n GeMe 2 Fe(CO) 4 (n=1, 2), react with chloral, propionaldehyde, and benzaldehyde to give heterocyclic expansion reactions. Thermal decompositions of the adducts produce germylated heterocycles, Me 2 Ge (CH 2 ) n GeMe 2 O, and alkylidene intermediates, which were isolated as the ylides (CO) 4 Fe - CH(R)PPh 3 + . The reaction of [bis(dimethylgermyl)alkane]iron tetracarbonyls with quinones involves an electron-transfer process that results in the formation of new digermylated dioxepane and dioxocane

Staphylococcus simulans strain secretes a non-induced lipase in the culture medium. Staphylococcus simulans lipase (SSL), purified to homogeneity, is a tetrameric protein (160 kDa) corresponding to the association of four lipase molecules. The 30 N-terminal amino acid residues were sequenced. This sequence is identical to the one of Staphylococcus aureus PS54 lipase (SAL PS54) and exhibits a high degree of homology with Staphylococcus aureus NCTC8530 lipase (SAL NCTC8530), Staphylococcus hyicus lipase (SHL) and Staphylococcus epidermis RP62A lipase (SEL RP62A) sequences. But the cloning and sequencing of the part of the gene encoding the mature lipase show some differences from SAL PS54 sequence, which suggest that it is a new sequence. The lipase activity was maximal at pH 8.5 and 37 degrees C. SSL is able to hydrolyze triacylglycerols without chain length specificity. A specific activity of about 1000 U/mg was measured on tributyrin or triolein as substrate at 37 degrees C and at pH 8.5 in the presence of 3 mM CaCl(2). In contrast to other staphylococcal lipases previously characterized, Ca(2+) is not required to express the activity of SSL. SSL was found to be stable between pH 4 and pH 9. The enzyme is inactivated after a few minutes when incubated at 60 degrees C. Using tripropionin as substrate, SSL does not present the interfacial activation phenomenon. In contrast to many lipases, SSL is able to hydrolyze its substrate in the presence of bile salts or amphiphilic proteins.