Ali H. Bahkali

Bio: Ali H. Bahkali is an academic researcher from King Saud University. The author has contributed to research in topics: Dothideomycetes & Pleosporales. The author has an hindex of 50, co-authored 287 publications receiving 9411 citations. Previous affiliations of Ali H. Bahkali include Yeungnam University & Landcare Research.

A polyphasic method for the identification of aflatoxigenic 'Aspergillus' species isolated from Camel feeds

Abstract: The main goal of our study was to identify Aspergillius spp. isolates by polyphasic taxonomic techniques. Differential culture media, biochemical and molecular characterization were applied to 21 isolates of Aspergillus flavus and Aspergillus niger from Saudi Arabia camel feeds. Six aflatoxin producing culture media were used for characterizing and identifying aflatoxigenic isolates. The blue fluorescent ring visible under UV light which indicates the ability to produce aflatoxin, by aflatoxinogenic strains was not observed for any of the tested non aflatoxigenic isolates. Biochemical characterization involving the screening of the isolates for five aflatoxins was also performed. As found, most isolates were capable of producing detectable levels of both B and G type's aflatoxins (AFs) and maltoryzine, although 4 of the 7 A. niger isolates failed to produce any detectable amount of AFs. PCR was performed using one set of primers that specifically targets the aflatoxin regulatory gene (aflR) involved in aflatoxin biosynthetic pathway as well as four specific primers for A. flavus and A. niger. The presence of the aflR gene did not correlate with aflatoxigenicity. Most of the fungi belonging to A. flavus group reacted positively with aflR primers that cover the region from 540 to 1338 of aflatoxin regulatory gene with product size of 798 base pairs (bp). All A. flavus isolates had positive PCR results using the primer pair FLA1-FLA. A unique DNA fragment of the expected 500-bp size was amplified in all A. flavus isolates, while no PCR products were visualized in other Aspergillus species or members belong to other fungal genera. Using the primer pairs OMt1R-OMt1F, a single fragment of about 1232 bp A. niger isolates was amplified but did not amplify with DNA extracted from other Aspergillus species or species belonging to other fungal genera. Detection and quantification of these two important aflatoxin-producing Aspergilli could provide important information to predict the aflatoxin profiles which may be present in the feed matrix.

Assessment of Chemopreventive Potential of the Plant Extracts against Liver Cancer Using HepG2 Cell Line.

Abstract: The edible parts of the plants Camellia sinensis, Vitis vinifera and Withania somnifera were extensively used in ancient practices such as Ayurveda, owing to their potent biomedical significance. They are very rich in secondary metabolites such as polyphenols, which are very good antioxidants and exhibit anti-carcinogenic properties. This study aims to evaluate the anti-cancerous properties of these plant crude extracts on human liver cancer HepG2 cells. The leaves of Camellia sinensis, Withania somnifera and the seeds of Vitis vinifera were collected and methanolic extracts were prepared. Then, these extracts were subjected to DPPH, α- amylase assays to determine the antioxidant properties. A MTT assay was performed to investigate the viability of the extracts of HepG2 cells, and the mode of cell death was detected by Ao/EtBr staining and flow cytometry with PI Annexin- V FITC dual staining. Then, the protein expression of BAX and BCl2 was studied using fluorescent dye to determine the regulation of the BAX and BCl2 genes. We observed that all the three extracts showed the presence of bioactive compounds such as polyphenols or phytochemicals. The W. somnifera bioactive compounds were found to have the highest anti-proliferative activity on human liver cancer cells.

Ligninsphaeria jonesii gen. et. sp. nov., a remarkable bamboo inhabiting ascomycete

Abstract: A new ascomycete species, inhabiting decaying bamboo culms, is introduced in this paper based on morphology and molecular evidence. Analyses of partial LSU sequence data place the taxon in a monophyletic clade within the order Pleosporales . Morphological characters of the taxon are also distinct from other members of Pleosporales . Ligninsphaeria jonesii gen. et sp. nov. is therefore introduced to accommodate the new taxon, which is characterized by its clypeate, scattered, deeply immersed ascomata, with a slit-like opening, long ostioles, cellular pseudoparaphyses, clavate asci containing broad-fusiform and 1-septate ascospores surrounded by a gelatinous cap at both ends. The phylogenetic analyses show that the new taxon is phylogenetically close but distinct from the families Amniculicolaceae and Testudinaceae , and forms a distinct clade from other taxa in Pleosporales . The new taxon is described and compared with similar taxa. A new genus Ligninsphaeria (Pleosporales, incertae sedis ) is introduced to accommodate this distinct lineage.

A new species

Abstract: We redescribe the only previously known species of Myrsidea from bulbuls, M. pycnonoti Eichler. Sixteen new species are described; they and their type hosts are: M. phillipsi ex Pycnonotus goiavier goiavier (Scopoli), M. gieferi ex P. goiavier suluensis Mearns, M. kulpai ex P. flavescens Blyth, M. finlaysoni ex P. finlaysoni Strickland, M. kathleenae ex P. cafer (L.), M. warwicki ex Ixos philippinus (J. R. Forster), M. mcclurei ex Microscelis amaurotis (Temminck), M. zeylanici ex P. zeylanicus (Gmelin), M. plumosi ex P. plumosus Blyth, M. eutiloti ex P. eutilotus (Jardine and Selby), M. adamsae ex P. urostictus (Salvadori), M. ochracei ex Criniger ochraceus F. Moore, M. borbonici ex Hypsipetes borbonicus (J. R. Forster), M. johnsoni ex P. atriceps (Temminck), M. palmai ex C. ochraceus, and M. claytoni ex P. eutilotus. A key is provided for the identification of these 17 species.

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Abstract: : The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

A European Database of Fusarium graminearum and F. culmorum Trichothecene Genotypes

Abstract: Fusarium species, particularly Fusarium graminearum and F. culmorum, are the main cause of trichothecene type B contamination in cereals. Data on the distribution of Fusarium trichothecene genotypes in cereals in Europe are scattered in time and space. Furthermore, a common core set of related variables (sampling method, host cultivar, previous crop, etc.) that would allow more effective analysis of factors influencing the spatial and temporal population distribution, is lacking. Consequently, based on the available data, it is difficult to identify factors influencing chemotype distribution and spread at the European level. Here we describe the results of a collaborative integrated work which aims (1) to characterize the trichothecene genotypes of strains from three Fusarium species, collected over the period 2000–2013 and (2) to enhance the standardization of epidemiological data collection. Information on host plant, country of origin, sampling location, year of sampling and previous crop of 1147 F. graminearum, 479 F. culmorum, and 3 F. cortaderiae strains obtained from 17 European countries was compiled and a map of trichothecene type B genotype distribution was plotted for each species. All information on the strains was collected in a freely accessible and updatable database (www.catalogueeu.luxmcc.lu), which will serve as a starting point for epidemiological analysis of potential spatial and temporal trichothecene genotype shifts in Europe. The analysis of the currently available European dataset showed that in F. graminearum, the predominant genotype was 15-acetyldeoxynivalenol (15-ADON) (82.9%), followed by 3-acetyldeoxynivalenol (3-ADON) (13.6%), and nivalenol (NIV) (3.5%). In F. culmorum, the prevalent genotype was 3-ADON (59.9%), while the NIV genotype accounted for the remaining 40.1%. Both, geographical and temporal patterns of trichothecene genotypes distribution were identified.