Extracts Of Aspergillus Flavus Research Articles

Cytotoxic Potential of Bioactive Compounds from Aspergillus flavus, an Endophytic Fungus Isolated from Cynodon dactylon, against Breast Cancer: Experimental and Computational Approach.

Endophytic fungi are a diverse group of microorganisms that colonize the inter- or intracellular spaces of plants and exhibit mutual benefits. Their interactions with the host plant and other microbiomes are multidimensional and play a crucial role in the production of secondary metabolites. We screened bioactive compounds present in the extracts of Aspergillus flavus, an endophytic fungus isolated from the roots of the medicinal grass Cynodon dactylon, for its anticancer potential. An in vitro analysis of the Ethyl acetate extract from A. flavus showed significant cytostatic effects (IC50: 16.25 μg/mL) against breast cancer cells (MCF-7). A morphological analysis of the cells and a flow cytometry of the cells with annexin V/Propidium Iodide suggested that the extract induced apoptosis in the MCF-7 cells. The extract of A. flavus increased reactive oxygen species (ROS) generation and caused a loss of mitochondrial membrane potential in MCF-7 cells. To identify the metabolites that might be responsible for the anticancer effect, the extract was subjected to a gas chromatography-mass spectrometry (GC-MS) analysis. Interestingly, nine phytochemicals that induced cytotoxicity in the breast cancer cell line were found in the extract. The in silico molecular docking and molecular dynamics simulation studies revealed that two compounds, 2,4,7-trinitrofluorenone and 3α, 5 α-cyclo-ergosta-7,9(11), 22t-triene-6beta-ol exhibited significant binding affinities (-9.20, and -9.50 Kcal/mol, respectively) against Bcl-2, along with binding stability and intermolecular interactions of its ligand-Bcl-2 complexes. Overall, the study found that the endophytic A. flavus from C. dactylon contains plant-like bioactive compounds that have a promising effect in breast cancer.

Determination of Bioactive Chemical Compounds of Aspergillus Flavus using GC/MS and Ftir and evaluation of Its Anti-Microbial Activity

The objective of this study was analysis of the secondary metabolite products and evaluation antibacterial activity. Bioactives are chemical compounds often referred to as secondary metabolites. Thirty one bioactive compounds were identified in the methanolic extract of Aspergillus flavus. Origanum vulgare (Crude) was very highly active 6.95±0.25 mm. The results of anti-fungal and anti-bacterial activity produced by Aspergillus flavus showed that the volatile compounds were highly effective to suppress the growth of Penicillium expansum 5.33±0.21and Pseudomonas eurogenosa (6.72 ± 0.23) mm.

In vitro antimicrobial study of Aspergillus flavus mycelial extract against different bacterial and fungal pathogenic strains

The aim of our research was to determine the antimicrobial activity of Aspergillus Flavus against some selected bacterial and fungal pathogen. The research work was done in the laboratory of Agricultural Chemistry, Department of Agricultural Chemistry, Agriculture University Peshawar, Khyber Pakhtunkhwa, Pakistan during the month of May 2013. The agar well diffusion method was used. The Acetonitrile and n-hexane extracts were used. The result of both the extracts of Aspergillus flavus was found to be effective against all the tested Bacterial i.e. P. aeruginosa, E. coli, S. aureus, S. aureus (Methicillin resistant), S. aureus (Vancomycin resistant), and fungal pathogen A. niger, A. oryzae, C. albican, P. distalatum, F. oxysporum. The result in Acetonitrile solvent was quite good from the result in n-hexane fraction, which confirmed that the secondary metabolites are more soluble in acetonitrile. Minimum inhibitory concentration (MIC), of the extracts against these bacterial and fungal strains were in the range of 0.20 mg/ml. Different phytochemical analysis result indicate the presence of secondary metabolites like mycotoxin, Aflatoxin, Kojic acids which may be responsible for antimicrobial properties. From our result is the concluded that extract of Aspergillus flavus have potential against fungal and bacterial strains.

Degradation of Metolachlor in Crude Extract of Aspergillus Flavus

Crude enzyme from a soil fungus, Aspergillus flavus, was isolated from a field soil following repeated applications of metolachlor [2-Chloro-N-(methoxy-1-methylethyl)-2′-ethyl-6′-methyl acetanilide]. Metolachlor hydrolysis by the crude enzyme extract was determined by enzyme assay. The tests were performed in phosphate buffer, pH 7.5, and the reaction was carried out at two herbicide concentrations (20 and 100 μg mL−1) and two crude extract volumes (0.2 and 0.5 mL of the homogenized crude extract mixture). The rate of metolachlor degradation was found faster in samples containing higher volume of crude extract, (T 1/2, 5.7 h) for both concentrations of the herbicide. The activities of enzymes responsible for dechlorination coupled with hydroxylation, N-dealkylation, and breaking of amide linkage were found responsible in the degradation.

Immunoassay identification ofAspergillus flavus using monoclonal antibodies raised to the whole cell extracts

Five separate monoclonal antibodies were produced against whole cell extracts ofAspergillus flavus and ELISA procedures used to characterise the reactivity of the antibodies to various fungal extracts. All five antibodies were specific to the aflatoxin producing fungi,A, flavus andA. parasiticus, and indicated no cross reactivity with otherAspergillus species, genera of several fungi or with other components which may be found in food samples whereA. flavus may be found.

Separation and purification of aflatoxins B1, B2, G1 and G2, and comparison of semi-synthetic aflatoxins B2 and G2 with naturally-occurring aflatoxins B2 and G2.

AbstractA method is described for the isolation of highly purified aflatoxins B1, B2, G1 and G2 from extracts ofAspergillus flavus. The four aflatoxins, isolated from background impurities by rapid passage of the extracts through an acid alumina column, are separated from each other by chromatography on a silica gel column. Aflatoxins B2 and G2 are prepared by hydrogenation of the mixture of aflatoxins B1, B2, G1 and G2 and then separated by elution from a silica gel column with chloroform containing 0.7% ethanol. A comparison of semi‐synthetic aflatoxins B2 and G2 with naturally‐occurring aflatoxins B2 and G2 shows no significant difference in physical properties.

An improved separation of aflatoxins.

AbstractCrude aflatoxin from a chloroform extract ofAspergillus flavus cultures on rice was precipitated with Skelly Solve B and chromatographed on 100–200 mesh silica gel columns, using ethyl acetate as eluant. On this column there was no separation of aflatoxins from each other, but most of the brown, oily material was removed. The next step in the purification was chromatography on 100–200 mesh silica gel columns with chloroform and 5% methanol/chloroform as eluants. A large part of the B1 was purified, but B2, G1 and G2 did not separate, and M1 had a brown oil that prevented crystallization. The M1 was purified by chromatography on Sephadex LH‐20 with chloroform; the brown material was retained while the M1 passed through. The separation of aflatoxin B2, G1, and G2 was achieved by column chromatography on Silica Gel H for TLC. In addition, aspertoxin was separated and identified. The purity and identity of the compounds were established by 100 MHz NMR.

Synthesis of oligosaccharides during enzymatic hydrolysis of cellobiose by Aspergillus flavus.

DURING our investigations on the synthesis of oligosaccharides from simple sugars by various mould extracts it was found that the mycelial extract of Aspergillus flavus was capable of synthesizing oligosaccharides from cellobiose. The dialysed extracts of the mould converted cellobiose into glucose and four other saccharides, three of which occupy positions below cellobiose and one between cellobiose and glucose on the paper chromatogram. Similar observations were reported recently by Crook and Stone1 by the action of Aspergillus niger on cellobiose. The substances were not identified. Barker et al. 2 have recently reported the synthesis by Aspergillus niger (strain 152) of some oligosaccharides which were identified as β-linked glucosaccharides. In view of the importance of this reaction in carbohydrate metabolism and in the mechanism of the synthesis of oligosaccharides, we report in this communication the results obtained on the identification of the substances formed from cellobiose.