Influence of the endomycorrhizal fungus Glomus mosseae on the development of peanut pod rot disease in Egypt

Glomus mosseae and the two pod rot pathogens Fusarium solani and Rhizoctonia solani and subsequent effects on growth and yield of peanut (Arachis hypogaea L.) plants were investigated in a greenhouse over a 5-month period. At plant maturity, inoculation with F. solani and/or R. solani significantly reduced shoot and root dry weights, pegs and pod number and seed weight of peanut plants. In contrast, the growth response and biomass of peanut plants inoculated with G. mosseae was significantly higher than that of non-mycorrhizal plants, both in the presence and absence of the pathogens. Plants inoculated with G. mosseae had a lower incidence of root rot, decayed pods, and death than non-mycorrhizal ones. The pathogens either alone or in combination reduced root colonization by the mycorrhizal fungus. Propagule numbers of each pathogen isolated from pod shell, seed, carpophore, lower stem and root were significantly lower in mycorrhizal plants than in the non-mycorrhizal plants. Thus, G. mosseae protected peanut plants from infection by pod rot fungal pathogens. Accepted: 10 February 2000     

Anti-biofilm potential of Lactobacillus plantarum Y3 culture and its cell-free supernatant against multidrug-resistant uropathogen Escherichia coli U12

Uropathogens develop biofilms on urinary catheters, resulting in persistent and chronic infections that are associated with resistance to antimicrobial therapy. Therefore, the current study was performed to control biofilm-associated urinary tract infections through assaying the anti-biofilm ability of lactic acid bacteria (LAB) against multidrug-resistant (MDR) uropathogens. Twenty LAB were obtained from pickles and fermented dairy products, and screened for their anti-biofilm and antimicrobial effects against MDR Escherichia coli U12 (ECU12). Lactobacillus plantarum Y3 (LPY3) ({"type":"entrez-nucleotide","attrs":{"text":"MT498405","term_id":"1843980272","term_text":"MT498405"}}MT498405), showed the highest inhibitory effect and biofilm production. Pre-coating of a microtitre plate with LPY3 culture was more potent than co-incubation. Pre-coating with LPY3 culture generated a higher anti-biofilm effect with an adherence of 14.5% than cell free supernatant (CFS) (31.2%). Anti-biofilm effect of CFS was heat stable up to 100 °C with higher effect at pH 4–6. Pre-coating urinary catheter with LPY3 culture reduced the CFU/cm² of ECU12 attached to the catheter for up to seven days. Meanwhile, CFS reduced the ECU12 CFU/cm² for up to four days. Scanning electron microscope confirmed the reduction of ECU12 adherence to catheters after treatment with CFS. Therefore, Lactobacillus plantarum can be applied in medical devices as prophylactic agent and as a natural biointervention to treat urinary tract infections.     

Purification by Immunoadsorption and Immunochemical Properties of NADP-Dependent Malic Enzymes from Leaves of C(3), C(4), and Crassulacean Acid Metabolism Plants

NADP:malic enzyme from corn (Zea mays L.) leaves was purified by conventional techniques to apparent homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Antibodies raised against this protein in rabbits were purified, coupled covalently to protein A-Sepharose CL-4B, and used as an immunoaffinity resin to purify the NADP:malic enzymes of the C₃ plants spinach (Spinacia oleracea L.) and wheat (Triticum aestivum L.), of the Crassulacean acid metabolism (CAM) plant Bryophyllum daigremontianum R. Hamed et Perr. de la Bathie and the C₄ plants corn, sugarcane (Saccharum officinarum L.), and Portulaca grandiflora L. Such procedures yielded homogeneous protein preparations with a single protein band, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, except for P. grandiflora L. with two bands. The specific activities of the purified proteins ranged between 56 and 91 units (milligrams per protein). NADP:malic enzyme represented up to 1% of the total soluble protein in C₄ plants, 0.5% in the CAM plant, and less than 0.01% in C₃ plants. In immunotitration tests involving immunoprecipitation and immunoinhibition of activity by an antiserum against the corn leaf enzyme, the NADP:malic enzymes of corn and sugarcane showed virtually full identity of epitopes, while the NADP:malic enzymes of the C₃ and CAM plants exhibited a cross-reaction of one-twentieth and one-fourth by these tests, respectively. The NADP:malic enzyme of P. grandiflora exhibited characteristics more closely related to the enzymes of C₃ and CAM plants than to those of C₄ plants.     

Addition of tryptophan methyl-ester on [60]fullerene: theoretical investigation of the mechanisms of azomethine ylides and fulleropyrrolidine formation

In this paper, we perform the synthesization of carbon nanoparticles for active principle vectorization, with the suggestion of a reaction mechanism of tryptophan methyl ester addition on [60]fullerene. Firstly, we studied the effect of tryptophan form on its addition reaction on [60]fullerene. So, in order to determine the preferred environment that makes this reaction the most favorable, we considered all tryptophan possible forms in our investigation: the molecular, the zwitterionic, and the dibasic forms. Secondly, we investigate the proposed reaction mechanism of tryptophan methyl ester addition on [60]fullerene using theoretical thermodynamic calculation. Our hypothesis suggests the formation of azomethine ylide molecule in a first step followed by its addition on [60]fullerene in the second step by the photo-addition reaction involving the oxygen in its singlet state. The stability of each reactive intermediate involved in this mechanism is verified thermodynamically. The 12 most stable conformations of azomethine ylide were observed through potential energy surface analysis. They were obtained by a relaxed scan of the four dihedral angles. The calculations were conducted on the optimized geometry of fulleropyrrolidine mono-adduct and the bulk values of its thermodynamic constants were also determined. Infrared spectra observed in 100–4000 cm^?1 region confirmed our hypothesis suggesting the first step of azomethine ylide formation followed by the second step of azomethine ylide addition on [60]fullerene by ν(C_aliphatic-C-N), ν(C_aromatic-C-N) and ^δ(N-H) coupled with ν(C-N) absorption bond.

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Graphical abstract Optimized geometry of the Fulleropyrrolidine monoaduct molecule.

     

Ni-hemin metal–organic framework with highly efficient peroxidase catalytic activity: toward colorimetric cancer cell detection and targeted therapeutics

Background

Given the great benefits of artificial enzymes, a simple approach is proposed via assembling of Ni²⁺ with hemin for synthesis of Ni-hemin metal–organic-frameworks (Ni-hemin MOFs) mimic enzyme. The formation of the Ni-hemin MOFs was verified by scanning electron microscopy, Transmission electron microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Energy-dispersive X-ray spectroscopy and UV–vis absorption spectroscopy. This novel nanocomposite exhibited surprising peroxidase like activity monitored by catalytic oxidation of a typical peroxidase substrate, 3,3,5,5′-tetramethylbenzidine, in the presence of H₂O₂. By using folic acid conjugated MOF nanocomposite as a recognition element, we develop a colorimetric assay for the direct detection of cancer cells.

Results

The proposed sensor presented high sensitivity and selectivity for the detection of human breast cancer cells (MCF-7) and Human Caucasian gastric adenocarcinoma. By measuring UV–vis absorbance response, a wide detection range from 50 to 10⁵ cells/mL with a detection limit as low as 10 cells/mLwas reached for MCF-7 cells. We further discuss therapeutics efficiency of Ni-hemin MOFs in the presence of H₂O₂ and ascorbic acid. Peroxidase-mimic Ni-hemin MOFs as reactive oxygen species which could damage MCF-7 cancer cells, however for normal cells (human embryonic kidney HEK 293 cells) killing effect was negligible.

Conclusions

Based on these behaviors, the developed method offers a fast, easy and cheap assay for the interest in future diagnostic and treatment application.

     

Spectroscopic determination of succinylcholine in dosage forms using eosin Y

Two simple and sensitive analytical assay methods using spectrophotometry and spectrofluorimetry techniques were developed for the estimation of succinylcholine chloride (SUC) in pharmaceutical preparations. The suggested methods are based on the formation of an ion pair complex formed between the drug and eosin Y spectrophotometrically (Method I), or the suppressive effect of succinylcholine on the native fluorescence property of eosin Y (Method II). The spectrophotometric method (Method I) involves measuring the absorbance of the complex between succinylcholine and eosin Y at 550 nm in Britton Robinson buffer of pH 3. However, the spectrofluorimetric method (Method II) involves measuring the quenching effect of the studied drug on the native fluorescence property of eosin Y at the same pH at 550 nm after excitation at 480 nm. The absorbance versus concentration of the drug is rectilinear over the range of 0.5 to 15 μg/ml. The formation constant was 3.5 × 10⁴ and the Gibb's free energy change was ?2.5 × 10⁴ J/mol. In Method II, the relative fluorescence intensity was directly proportional to SUC concentration over the range of 0.05 to 1 μg/ml. The proposed methods allowed a successful application to the estimation of succinylcholine ampoules. An explanation of the reaction pathway was postulated.     

Exploration and local utilization of medicinal vegetation naturally grown in the Deusai plateau of Gilgit,Pakistan

In the study area, the traditional knowledge regarding the uses of local wild medicinal plants for the health care of human and domestic animals is totally in hold of old people. The young ones are unaware about such an indispensable practices. The objective of the current study was to transfer this sort of precious knowledge from old members of the community to young generations in documented form.     

Life forms,leaf size spectra,regeneration capacity and diversity of plant species grown in the Thandiani forests,district Abbottabad,Khyber Pakhtunkhwa,Pakistan

The life form and leaf size spectra of plant species of the Thandiani forests, district Abbottabad, were studied during the summer of 2013. These forests host 252 plant species of 97 families. Biological spectra showed that Hemicryptophytes (80 spp., 31.74%) were dominant followed by Megaphanerophytes (51 spp., 20.24%), Therophytes (49 spp., 19.44%) and Nanophanerophytes (45 spp., 17.86). Hemicryptophytes are the indicators of cold temperate vegetation. At the lower elevations, Megaphanerophytes and Nanophanerophytes were dominant which confirm trees as dominant habit form due to high soil depth, moisture and temperature factors. Data on Leaf spectra in the area showed that Microphyllous (88 spp., 34.92%) species were dominant followed by Leptophyllous (74 spp., 29.36%) and Nanophyllous (60 spp., 23.80%). The Microphyllous plants again are the indicator of cold temperate zone as the area is situated at an elevation of 1191–2626 m. Similarly, Nanophylls were dominant at lower elevations. Data on family importance values and diversity among various communities were also recorded. Life form and Leaf spectra studies could be used to understand the micro climatic variation of the region.