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In the present paper, the effect of different bent angles on structural stability, electronic structure, and optical properties of Na absorbed borophene system is investigated using the density functional theory. The structure of the borophene was almost unchanged and the planar structure was not disrupted after the adsorption of a Na atom. Directly above the bottom B–B bonds is considered as the optimal adsorption position of single. The stability of the Na adsorbed borophene system can be decreased under the condition of different bent angles. The adsorption of Na atoms changes the energy band structure of the intrinsic borophene according to the calculation results of energy band structure and density of states, which resulting the conduction band contains more impurities. The 2p orbital of Na and the 3p orbital of B hybridize between −4 eV and 6 eV. Bending deformation gives rise to the electron transfer between Na atoms and B atoms. In terms of optical properties, the bending deformation improves the absorption of infrared light and the catalytic activity of light in the adsorbed system. • The structure of the borophene was almost unchanged and the planar structure was not disrupted after the adsorption of a Na atom. • The stability of the Na adsorbed borophene system can be decreased under the condition of different bent angles. • The adsorption of Na atoms changes the energy band structure of the intrinsic borophene so that its conduction band contains more impurities. • The bending deformation improves the absorption of infrared light and the catalytic activity of light in the adsorbed system. [ABSTRACT FROM AUTHOR]

With the development of industrialization, the use of mercury in industry has become more and more widespread, causing serious impacts on the environment. It is therefore urgent to find new effective ways to combat mercury pollution. In this paper, The effect of C, O, P, Ni and Au doping on the adsorption of Hg atoms by WS 2 has been investigated based on the first nature principle of density functional theory. The electronic structures and optical properties of the adsorbed systems were calculated after atomic doping. The results show that the absolute value of the adsorption energy of the intrinsic adsorption system is small and does not favour the adsorption of Hg on WS 2. However, after C, P, Ni and Au doping, the adsorption energy of the system is significantly increased and a strong charge transfer between WS 2 and Hg atoms occurs, as well as a significant change in the band gap of the structure. This suggests that atomic doping favors the adsorption of Hg by WS 2. The effect of O doping on the adsorption system is not significant. In addition, a study of the optical properties revealed that the static dielectric constants of the system appeared to increase to varying degrees after the doping of the atoms. The doping of P, Ni and Au atoms increases the light absorption coefficient and contributes to the photocatalytic efficiency of the structures. The doped atoms cause a red shift in the reflectivity peak of the adsorbed system. In summary, the doping of C, P, Ni and Au enhances the adsorption of Hg atoms on WS 2. O doping has less effect on the adsorption of Hg on WS 2. • In this paper, the effect of C, O, P, Ni and Au doping on the adsorption of Hg atoms by WS2 was investigated. • The results show that atomic doping favors the adsorption of Hg by WS2. • Atomic doping alters the electronic properties of the structure. • Atomic doping alters the optical properties of the structure. [ABSTRACT FROM AUTHOR]

In this study, a cost effective activated carbon was prepared using peanut shells as precursor material, which was used for treatment of soil eluent containing explosive contaminants. The effects of temperature, contact time, adsorbent dosage and pH were optimized by response surface methodology (RSM). The Langmuir and Freundlich adsorption isotherm models were used to fit the adsorption process of chemical oxygen demand (COD). The results showed that the maximum COD removal was obtained when temperature, time, absorbent dosage and pH were at 15 °C, 236 min, 6.06 g and 4, respectively. The adsorption of COD on activated carbon was in accord with Freundlich isotherm. Pseudo-second-order model can be used to describe the adsorption kinetics of COD. After adsorption at the optimized conditions, the chrominance reduced from 400 to 5°, COD decreased from 1012.60 to 73.51 mg L −1 , with COD removal of 92.74%, the concentrations of the two main contaminants 2, 4-dinitrotoluene-3-sulfonate (2, 4-DNT-3-SO 3 - ) and 2, 4-dinitrotoluene-5-sulfonate (2, 4-DNT-5-SO 3 - ) reduced from and 332.66 and 14.24 mg L −1 to 0 mg L −1 , respectively. The activated carbon produced from peanut shells could be a potential cost effective adsorbent for treatment of soil eluent containing explosive pollutants. [ABSTRACT FROM AUTHOR]

Heavy metal remediation, such as cadmium (Cd2+) by microbial strains is efficient and environment-friendly. In this current study, we exploited the potential of Bacillus strains (Cd2+-tolerant; NMTD17, GBSW22, and LLTC96) to regulate Cd2+ biosorption mechanisms and improve rice seedling growth. The results showed that initial concentration and contact time affected Cd2+ biosorption, and the kinetic models of pseudo orders were effective in the elaborate biosorption process. Mainly, the bacterial cell wall had the potential for Cd2+ biosorption, and we found non-significant biosorption alterations among bacterial strains' inner and outer surfaces of cell membranes. Furthermore, the Fourier transform infrared (FTIR) spectroscopy analysis identified the differences in functional groups, such as C–N, PO 2 , –SO 3 , C O, COOH, C–O, C–N, –OH, and –NH that interact in biosorption by Bacillus strains. The scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) examination revealed that the binding of Cd2+ to microbes was mostly based on ion exchange pathways. Moreover, the Bacillus strains responded to Cd2+ stress in rice under pot experiment at various concentrations (0, 0.25, and 0.50 mg kg−1), and they also influenced the chlorophyll contents and antioxidants activities were studied. The analysis of physio-morphological parameters was observed to be increased, which indicated that all Bacillus strains showed significant effects on rice growth under Cd2+ stress. These results revealed that the selected strains had the capability for additional use in the development of Cd2+ bioremediation methods. These strains also provided plant growth-promoting (PGP) traits that can alleviate the harmful effects of Cd2+ in rice plants. [Display omitted] • Bacillus sp. increased adsorption of Cd2+ on the cell wall. • Lterations in functional groups that were involved in Bacillus -Cd2+ biosorption. • Bacillus microbial strains increased Cd2+ immobilization in soil. • Microbial strains reduced Cd2+ content and improved plant growth. • Suitable microbial species that may be modified to enhance Cd2+ biosorption. [ABSTRACT FROM AUTHOR]

A novel thermostable mannanase from a newly isolated Bacillus pumilus GBSW19 has been identified, expressed, purified and characterized. The enzyme shows a structure comprising a 28 amino acid signal peptide, a glycoside hydrolase family 5 (GH5) catalytic domain and no carbohydrate-binding module. The recombinant mannanase has molecular weight of 45 kDa with an optimal pH around 6.5 and is stable in the range from pH 5–11. Meanwhile, the optimal temperature is around 65 °C, and it retains 50% relative activity at 60 °C for 12 h. In addition, the purified enzyme can be activated by several ions and organic solvents and is resistant to detergents. Bpman5 can efficiently convert locus bean gum to mainly M2, M3 and M5, and hydrolyze manno-oligosaccharides with a minimum DP of 3. Further exploration of the optimum condition using HPLC to prepare oligosaccharides from locust bean gum was obtained as 10 mg/ml locust bean gum incubated with 10 U/mg enzyme at 50 °C for 24 h. By using this enzyme, locust bean gum can be utilized to generate high value-added oligosaccharides with a DP of 2–6. [ABSTRACT FROM AUTHOR]

Highlights: [•] We introduce a new soybean lectin gene (lec-s) into tobacco plants. [•] We examine transgenic tobacco plants’ resistance to pathogens and pests [•] The transgenic plants could resist to the infection of Phytophthora nicotianae. [•] The transgenic plants reduce the weight gain of Spodoptera exigua larvae. [•] The transgenic plants retard S. exigua larvae's development and metamorphosis. [Copyright &y& Elsevier]

Abstract: Bacillus amyloliquefaciens C06, an effective biological agent in controlling brown rot of stone fruit caused by Monilinia fructicola, was also found to produce extra-cellular mucilage and form mucoid colonies on semi-solid surfaces. This study aimed to characterize the extra-cellular mucilage produced by B. amyloliquefaciens C06 using transposon mutagenesis and biochemical and physical analyses. The mucilage production in B. amyloliquefaciens C06 was demonstrated to be associated with ywsC gene expression and characterized to be of high molecular weight, consisted of only glutamic acid and linked with non-peptide bonds, thus identified as γ-polyglutamic acid (γ-PGA). Compared with wild type B. amyloliquefaciens C06, its mutants deficient in producing γ-PGA, e.g. M106 and C06ΔywsC showed less efficiency in biofilm formation, surface adhesion and swarming ability. It was also demonstrated that γ-PGA was not essential for C06 to form colony on semi-solid surfaces, but was able to improve its colony structure. In vivo evaluation showed that disruption of γ-PGA production in C06ΔywsC impaired its efficiency of colonizing apple surfaces. [ABSTRACT FROM AUTHOR]

Natural β -carboline alkaloids are ideal models for the discovery of pharmaceutically important entities. Various 1-substituted β -carbolines were synthesized from commercially inexpensive tryptophan and demonstrated significant in vitro antifungal activity against G. graminis. Significantly, compound 4m (EC 50 = 0.45 μM) with carboxamide at 1-position displayed the best efficacy and nearly 20 folds enhancement in antifungal potential compared to Silthiopham (EC 50 = 8.95 μM). Moreover, compounds 6 , 7 , and 4i exhibited excellent in vitro antifungal activities and in vivo protective and curative activities against B. cinerea and F. graminearum. Preliminary mechanism studies revealed that compound 4m caused reactive oxygen species accumulation, cell membrane destruction, and deregulation of histone acetylation. These findings indicated that 1-carbamoyl β -carboline can be selected as a promising model for the discovery of novel and broad-spectrum fungicide candidates. [Display omitted] • 1-Carbamoyl β -carbolines were synthesized and discovered as novel fungicide candidates. • Compound 4m exhibited nearly 20 folds enhancement in antifungal potential compared to Silthiopham. • Compound 4m inhibit G. graminis by inducing ROS accumulation and destructing cell membrane permeability. • Compound 4m can decrease histone acetylation levels of F. graminearum by affecting the activity of protein FgGcn5. [ABSTRACT FROM AUTHOR]

The bacterium Pantoea ananatis is associated with devastating plant diseases that cause serious economic losses. Strain DZ-12 was previously isolated from maize brown rot leaves in Hebei Province, China and its genome sequencing revealed that it belongs to P. ananatis. It contains a large, endogenous plasmid, pDZ-12. Different studies have shown that virulence determinants are frequently carried on plasmids. To determine whether pDZ-12 from P. ananatis has any effect on pathogenicity, the plasmid was eliminated by substituting its native replication genes with temperature-sensitive replication genes. The resulting temperature-sensitive plasmid could be cured by growing cells at high temperature (37℃). Loss of pDZ-12 from P. ananatis DZ-12 led to a decreased disease severity in maize plants suggesting that the endogenous plasmid is important for pathogenesis. Loss of pDZ-12 also affected the ability of the bacterium to form biofilms. The study provides the first evidence that the endogenous plasmid of P. ananatis DZ-12 is important for pathogenesis in maize plants and carries genes involved in biofilm formation. This study also presents the first report on curing a plasmid from P. ananatis. [ABSTRACT FROM AUTHOR]

• Synthesis of vegetable oil-based waterborne polyurethane with different R value. • Performances of polyurethane was adjusted by increasing R values. • Polyurethane films can be fully degraded in the 5 wt% sodium hydroxide. • The possible degradation mechanism was proved via FT-IR, tensile strength and SEM. In this study, the fully degradable soybean oil-based waterborne polyurethanes (SWPU) were prepared, and the mechanical properties, thermal properties and hydrophilicity of SWPU films were adjusted by changing the R value. First, soybean oil-based polyol was fabricated via epoxy soybean oil and ricinoleic acid in the absence of solvent and catalyst. Then, the resulting polyol was mixed with isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA), trimethylamine (TEA) and ethylenediamine (EDA) to synthesize polyurethane emulsion with different R value (the molar ration of –NCO/–OH). The result showed that as the R value increased, the tensile strength of SWPU film was increased from 10.02 to 27.32 MPa, the initial decomposition temperature of polyurethane films was improved from 201 ℃ to 246 ℃, the T g,h was increased from 68 to 130 ℃ and the water contact angle of SWPU films were enhanced from 82.4° to 95.5°. It can be explained that the degree of crosslinking of the polyurethane elastomer was improved and the interaction of the molecular chains became stronger with larger R value. Also, all SWPU films were placed in the 3 wt% sodium hydroxide solution at 45 ℃ to test the degradability, and the weight loss of samples at different degradation time were calculated, respectively. Finally, the morphology, FT-IR and tensile strength of samples was observed before and after degradation, and a possible mechanism of degradation was studied. The technique reported here demonstrated that it was possible to develop the degradable materials. [ABSTRACT FROM AUTHOR]

• Novel nanocomposites PC prepared by simple peptide-forming reactions. • Nanocomposite PC synergistically modified vegetable oil based waterborne polyurethane. • Synthesis of high-performance vegetable oil based waterborne polyurethane composite film. In this study, a graft modified Octa(aminopropyl) polyhedral oligomeric silsesquioxane (OPOSS)/ TEMPO-oxidized cellulose microfibrils (TOCMF) nanocomposite material (named PC) was prepared by a simple peptide-forming reaction to overcome the disadvantages of nanocellulose materials which have limited their application in environmentally friendly waterborne polyurethanes. The modified vegetable oil-based waterborne polyurethane (WPU) was prepared by reacting the excess amino group on the POSS with the -NCO group on the polyurethane matrix in the in-situ polymerization, in which the POSS particles function as a button-like bond between the oxidized cellulose and the polyurethane matrix. And the similar filamentous structure of TOCMF to the linear polyurethane matrix structure could greatly weaken the negative impact of the rigid structure of POSS particles on processability (Elongation at break). The performance test results showed that the mechanical properties, thermal stability and water resistance of the modified WPU composite film are greatly improved by the synergistic effect of the two nano materials. The initial decomposition temperature and water contact angle of the WPU composite film with a PC content of 0.7 wt.% were increased by 41.9 °C and 10°, respectively. Especially, the tensile strength of WPU/PC-0.7 wt.% was twice that of pure WPU. [ABSTRACT FROM AUTHOR]

• Candida oleophila effectively controlled postharvest gray mold of kiwifruit. • Two Rlm1 mutants (Δ Rlm1-1 and Δ Rlm1-2) of C. oleophila were generated. • The two mutants were more sensitive to a variety of stresses, compared to WT. • The two mutants exhibited lower biocontrol efficacy against gray mold. • The study shed light on the function of Rlm1 in a postharvest biocontrol yeast. Biological control utilizing antagonistic yeasts has been actively pursued as an alternative to synthetic fungicides for the management of postharvest diseases. Abiotic stress resistance is an important attribute for antagonistic yeasts, directly associated with their biocontrol efficacy. The MADS-box transcription factor, Rlm1 , has been reported to regulate the response of model yeasts to cell wall stress. Rlm1 in the antagonistic yeast, Candida oleophila , was found to play a role in resistance to salt, heat, and oxidative stress. Two Rlm1 mutants (Δ Rlm1-1 and Δ Rlm1-2) were generated. Compared to the wild-type (WT), C. oleophila I-182, Δ Rlm1-1 , and Δ Rlm1-2 were more sensitive to a variety of stresses, including heat, salt, and oxidative stress. The mutants also exhibited lower biocontrol efficacy against gray mold caused by Botrytis cinerea , and slower growth in kiwifruit wounds with respect to the WT. This study provided the information to understand the relationship between the Rlm1 transcription factor, stress resistance, and biocontrol efficacy of antagonistic yeasts used for the biocontrol of postharvest diseases. [ABSTRACT FROM AUTHOR]

An environmentally friendly waterborne polyurethane based on castor oil was prepared and modified by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose microfibers (TOCMF). The TOCMF with surface-attached active carboxyl groups was obtained by TEMPO/NaClO/NaBr system, and then the modified castor oil-based waterborne polyurethane was prepared by the synergistic action of covalent bond and hydrogen bond between TOCMF and prepolymer in the in-situ polymerization reaction. The introduction of carboxylate on the surface of TOCMF facilitated stabilization of the thickness of the double layer of the emulsion particles to form stable WPU/TOCMF dispersions. Benefiting from the filamentous structural effects of TOCMF and the covalent bond and hydrogen bond dual interactions in WPU matrix, WPU/TOCMF composite films showed improvement in tensile strength and thermal decomposition temperature. Tensile strength of composite films increased from 17.89 to 30.31 MPa with increasing TOCMF amount from 0 to 1.00 wt%. T 5% of composite films increased from 202.6 to 239.3 °C with increasing TOCMF amount from 0 to 0.75 wt%. It was observed by SEM that the presence of agglomeration in the composite film with 1.25 and 1.50 wt% TOCMF, and the occurrence of agglomeration caused the performance of the composite film to deteriorate sharply. Image 1 • High aspect ratio, filamentous structure of TOCMF was prepared by TEMPO/NaClO/NaBr system. • Acting on TOCMF and polyurethane matrix in both hydrogen and covalent bonds. • Synthetic environmentally friendly vegetable oil based waterborne polyurethane composite. • WPU/TOCMF composite film exhibits excellent mechanical properties and thermal stability. [ABSTRACT FROM AUTHOR]