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In the present study, the production of cellulase by Trichoderma reesei under solid-state fermentation of nettle biomass was promoted through supplementation of the culture media using carbonaceous additives and comprehensive optimization of the cultivation via the Taguchi method. CMCase activities about 5.5-6.1 U/gds were obtained by fermentation of the autoclave-pretreated biomass, among various chemical and physical pretreatments. Then, several additives including Tween 80, betaine, carboxymethyl cellulose, and lactose were individually or in combination added to the culture media to induce the enzyme production. The results proved that such additives could act as either inducers or inhibitors. Furthermore, CMCase activity surprisingly increased to 14.0 U/gds by supplementing the fermentation medium with the optimal mixture of additives including 0.08 mg/gds Tween 80, 0.4 mg/gds betaine, and 0.2 mg/gds carboxymethyl cellulose. Factor screening according to Plackett-Burman design confirmed that the levels of Urea and MgSO4 among basal medium constituents as well as pH of the medium were significantly affected CMCase production. By optimizing the levels of these factors, CMCase activity of 18.8 U/gds was obtained, which was noticeably higher than that of fermentation of the raw nettle. The applied procedure can be promisingly used to convert the nettle biomass into valuable products.

For [C(O)NH](N)2P(O)-based structures, the magnitude of the differences in the N—H...O, H...O=P and H...O=C angles has been evaluated when the N—H bond lengths, determined by X-ray diffraction, were compared to the neutron normalized values and the maximum percentage difference was obtained,i.e.about 3% for the angle even if the N—H bond lengths have a difference of about 30% (0.7 Å for the X-ray and 1.03 Å for the neutron-normalized value). The symmetries of the crystals are discussed with respect to the symmetry of the molecules, as well as to the symmetry of hydrogen-bonded motifs, and the role of the most directional hydrogen bond in raising the probability of obtaining centrosymmetric crystal structures is investigated. The work was performed by considering nine new X-ray crystal structures and 204 analogous structures retrieved from the Cambridge Structural Database.

Improving the production of lignocellulose-degrading enzyme such as cellulase and xylanase substantially increases the chance for cost-competitive production of cellulosic biofuel and other chemicals from such a biomass. In this study, the possible effects of carbonaceous additives including Tween 80, betaine, carboxymethyl cellulose (CMC) and lactose on cellulases and xylanase production were investigated individually or in combination. The enzymes were produced by Trichoderma reesei in solid state fermentation of wheat straw, wheat bran, rice straw and rice husk. The results proved that an individual additive could be an inducer or inhibitor based on the type of carbon source and targeted enzyme. For applying additives in combination, their roles depended on not only the type of carbon source and targeted enzyme but also their concentrations. Furthermore, a single additive with inhibitory role could be an inducer in combination with the other additives. For the best induction, the xylanase activity was about 469 U/gds with betaine as a single inducer. It increased to 218% with the mixture of Tween 80, betaine and CMC, supporting the combination of additives is more inducing. Applying the mixture of inducers can highly improve the process efficiency in lignocellulose-based biorefineries for both fuel and chemicals production.

The synthesis, spectral characteristics (IR and NMR), elemental analysis and X-ray crystal structure of phosphorothioic triamide SP(NC5H10)3 (1) and its dinuclear mercury(II) complex [Hg2(μ...

For [C(O)NH](N)

The hydrogen bond pattern of N-(4-methoxybenzoyl)-N′,N″-bis(4-methylbenzyl)-phosphoric triamide, C24H28N3O3P, (I), was investigated. In the crystal structure, the molecules are aggregated through N...

New oxo-bridge, mixed metal complex, [Fe2NiO(CH3CH2COO)6(H2O)3]·0.5H2O has been synthesized from the direct reaction between metal nitrate and propanoic acid and characterized by elemental analysis, infrared and electronic spectroscopy and single-crystal X-ray crystallography. This complex have a typical μ3-oxo trinuclear structure: (a) three metal atoms are situated in the apexes of the equilateral triangle; (b) μ3-oxygen atom and six propanoate ligands fulfill the bridge functions; (c) the monodentate water ligands complete the octahedral geometry of the metal ions. It crystallized in the triclinic, space group type P 1 ¯ . Two strong bands were observed in IR spectra at ∼1590 and ∼1420 (cm−1) stretching vibrations, the coordination mode of the carboxylate ligand can be assigned on the basis of the difference (Δν ⩽ 200 cm−1) of these two frequencies.

Background: Hearing loss is a common disorder affecting millions of individuals worldwide with opproximately 1 in 1000 newborns. A novel gene, DFNB59 encods Pejvakin has been recently shown to cause neural deafness. The aim of this study was to determine the frequency of DFNB59 gene mutations in 93 deaf pupils in Sistan & Baluchestan province.Materials and Method: We investigated the frequency of DFNB59 gene mutations in the coding regions (exons 2-7) of the gene.DNA was extracted following the standard phenol chloroform procedure, the frequency of DFNB59 gene mutations was investigated using PCR-SSCP /HA strategy.Results: No pathogenic variant was detected in samples studied. However, one polymorphism including 793C>G was determined in 3 of 93 (3.2%) subject examined.Conclusion: The results of this study showed no association between DFNB59 gene mutations and hearing loss in Sistan va Baluchestan province

Background Using peak expiratory flow (PEF) as an alternative to spirometry parameters (FEV1 and FVC), for detection of airway reversibility in diseases with airflow limitation is challenging. We developed logistic regression (LR) model to discriminate bronchodilator responsiveness (BDR) and then compared the results of models with a performance of >18%, >20%, and >22% increase in ΔPEF% (PEF change relative to baseline), as a predictor for bronchodilator responsiveness (BDR). Materials and Methods PEF measurements of pre-bronchodilator, post-bronchodilator and ΔPEF% of 90 patients with asthma (44) and chronic obstructive pulmonary disease (46) were used as inputs of model and the output was presence or absence of the BDR. Results Although ΔPEF% was a poor discriminator, LR model could improve the accuracy of BDR. Sensitivity, specificity, positive predictive value, and negative predictive value of LR were 68.89%, 67.27%, 71.43%, and 78.72%, respectively. Conclusion The LR is a reliable method that can be used clinically to predict BDR based on PEF measurements.