Variation in Essential Oil Yield and Composition of Dorema aucheri Boiss., an Endemic Medicinal Plant Collected from Wild Populations in Natural Habitats

In the present research, variability in essential oil (EO) composition of five Dorema aucheri populations collected from natural habitats in different regions of Iran, were investigated. The EO content of populations varied from 0.28 to 0.68%. According to gas chromatography/mass spectrometry analysis, β‐caryophyllene (7.17 – 35.73%), thymol (23.45 – 29.64%), β‐gurjunene (2.58 – 5.89%), carvacrol (1.32 – 2.67%) and cuparene (1.97 – 2.98%) were the major components. Hierarchical cluster, principal component and canonical correspondence analyses classified the studied populations into three groups based on major EO components. The environmental parameters of the collected sites were also evaluated. According to the results, it might be suggested that sandy soils with high mean annual precipitation were major environmental factors influencing the amount of β‐caryophyllene, while thymol, cuparene and caryophyllen oxide increased in silty and clay soils. Finally, the population collected in high altitudes and clay soils had higher amount of β‐gurjunene.     

Virtual screening,docking, and dynamics of potential new inhibitors of dihydrofolate reductase from Yersinia pestis

In the present work, we propose to design drugs that target the enzyme dihydrofolate redutase (DHFR) as a means of a novel drug therapy against plague. Potential inhibitors of DHFR from Yersinia pestis (YpDHFR) were selected by virtual screening and subjected to docking, molecular dynamics (MD) simulations, and Poisson–Boltzmann surface area method, in order to evaluate their interactions in the active sites of YpDHFR and human DHFR (HssDHFR). The results suggested selectivity for three compounds that were further used to propose the structures of six new potential selective inhibitors for YpDHFR.     

Identification of the New Pathogen (Stemphylium lycopersici) Causing Leaf Spot on Pepino (Solanum muricatum)

Pepino (Solanum muricatum var. pepino) plants were found affected by an extensive leaf spot caused by plant pathogenic fungi during a survey in the Cameron highlands, Pahang state, Malaysia. Symptomatic leaf samples were collected from infected pepino plants and cultivated on PDA medium, and the pathogen was isolated and purified; then, consequently, all isolates were identified as Stemphylium lycopersici on the basis of their cultural and morphological characteristics and combined sequences of the internal transcribed spacer (ITS) and glyceraldehyde‐3‐phosphate dehydrogenase (gpd) regions. A pathogenicity assay on detached leaves further confirmed that S. lycopersici causes leaf spot disease. To the best of our knowledge, this is the first report of S. lycopersici causing leaf spot on pepino in Malaysia and worldwide.     

Aspartyl Protease-Mediated Cleavage of BAG6 Is Necessary for Autophagy and Fungal Resistance in Plants

The Bcl-2-associated athanogene (BAG) family is an evolutionarily conserved group of cochaperones that modulate numerous cellular processes. Previously we found that Arabidopsis thaliana BAG6 is required for basal immunity against the fungal phytopathogen Botrytis cinerea. However, the mechanisms by which BAG6 controls immunity are obscure. Here, we address this important question by determining the molecular mechanisms responsible for BAG6-mediated basal resistance. We show that Arabidopsis BAG6 is cleaved in vivo in a caspase-1-like-dependent manner and via a combination of pull-downs, mass spectrometry, yeast two-hybrid assays, and chemical genomics, we demonstrate that BAG6 interacts with a C2 GRAM domain protein (BAGP1) and an aspartyl protease (APCB1), both of which are required for BAG6 processing. Furthermore, fluorescence and transmission electron microscopy established that BAG6 cleavage triggers autophagy in the host that coincides with disease resistance. Targeted inactivation of BAGP1 or APCB1 results in the blocking of BAG6 processing and loss of resistance. Mutation of the cleavage site blocks cleavage and inhibits autophagy in plants; disease resistance is also compromised. Taken together, these results identify a mechanism that couples an aspartyl protease with a molecular cochaperone to trigger autophagy and plant defense, providing a key link between fungal recognition and the induction of cell death and resistance.     

Design,Synthesis, and Cholinesterase Inhibition Assay of Coumarin‐3‐carboxamide‐N‐morpholine Hybrids as New Anti‐Alzheimer Agents

A new series of coumarin‐3‐carboxamide‐N‐morpholine hybrids 5a – 5l was designed and synthesized as cholinesterases inhibitors. The synthetic approach for title compounds was started from the reaction between 2‐hydroxybenzaldehyde derivatives and Meldrum's acid to afford corresponding coumarin‐3‐carboxylic acids. Then, amidation of the latter compounds with 2‐morpholinoethylamine or N‐(3‐aminopropyl)morpholine led to the formation of the compounds 5a – 5l . The in vitro inhibition screen against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) revealed that most of the synthesized compounds had potent AChE inhibitory while their BuChE inhibitions are moderate to weak. Among them, propylmorpholine derivative 5g (N‐[3‐(morpholin‐4‐yl)propyl]‐2‐oxo‐2H‐chromene‐3‐carboxamide) bearing an unsubstituted coumarin moiety and ethylmorpholine derivative 5d (6‐bromo‐N‐[2‐(morpholin‐4‐yl)ethyl]‐2‐oxo‐2H‐chromene‐3‐carboxamide) bearing a 6‐bromocoumarin moiety showed the most activity against AChE and BuChE, respectively. The inhibitory activity of compound 5g against AChE was 1.78 times more than that of rivastigmine and anti‐BuChE activity of compound 5d is approximately same as rivastigmine. Kinetic and docking studies confirmed the dual binding site ability of compound 5g to inhibit AChE.     

Diversity and Antimicrobial Activity of Actinomycetes Isolated from Lut Desert: The Extremely Arid Climatic Zones of Iran

Lut desert is situated in one of the extremely arid climatic zones of Iran and is one of the hottest deserts in our plant with the extreme fluctuation of temperature over a day. The main objective of this study is to characterize the diversity of the culturable actinomycetes and preliminary evaluation of their extracts as antimicrobial components on drug resistant pathogens. Twenty-four soil samples were collected, successively diluted and inoculated into the different culture media to support the growth of most culturable bacteria including actinomycetes. Phenotypic and molecular methods were used for accurate identification of recovered isolates particularly actinomycetes at the genus and species levels. The isolates were also evaluated for their inhibitory activities against drug resistant Acinetobacter baumannii, Enterococcus faecium, Klebsiella pneumoniae and Staphylococcus aureus. A total of 56 isolates recovered from the samples. Based on phenotypic tests, 41 isolates were identified as actinomycetes, amongst them 8 isolates were active against drug resistant pathogens. Our study revealed Lut desert, as one of the hottest deserts in the world, is the habitat to diverse taxa of bacteria particularly actinomycetes which have potential novel antimicrobial components.

     

Novel CaO/polylactic acid nanoscaffold as dental resin nanocomposites and the investigation of physicochemical properties

In this study, for the first time, calcium oxide (CaO)/polylactic acid nanoscaffolds were synthesized by co‐precipitation assistant reverse micelles method. The physical and chemical (physicochemical) properties of the structures as dental resin composites were also studied. Nanocomposite materials as primary and basic dental compounds can be conveniently applied as dental filling materials with a high esthetic quality. In this research nanoscaffolds act as a bed for nanoparticles and improve the mechanical and chemical (mechanochemical) properties, CaO nanoparticles were loading in polylactic acid nanoscaffold as a bioactivity polymer for usage in the dental resin composites. Mechanical properties of the dental resin composite containing CaO/polylactic acid nanoscaffold were calculated: the flexural strength (137.2 MPa), modulus (12.9GPa) and compressive strength (344.2 MPa). Potential of the basic nanoparticle and the products were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), dynamic light scattering (DLS), ultraviolet‐visible spectroscopy (UV‐visible) and atomic force microscopy (AFM) showed the size of the optimized nanostructures was about 85 to 120 nm. According to TGA results of polylactic acid nanofibers with thermal stability below 300°C these high thermal stability materials can be used as dental resin composites.     

Growth Behavior and Fatty Acid Production of Probiotics,Pediococcus acidilactici and Lactococcus lactis,at Different Concentrations of Fructooligosaccharide: Studies Validating Clinical Efficacy of Selected Synbiotics on Growth Performance of Caspian Roach (Rutilus frisii kutum) Fry

Probiotics and Antimicrobial Proteins - Growth behavior and production of short-chain fatty acid (SCFA) of two probiotics, Pediococcus acidilactici and Lactococcus lactis, each at...