Molecular identification of actinomycetes with antimicrobial, antioxidant and anticancer properties

The objectives of this study were to isolate and identify the actinomycetes strains from the soil and marine sediments and to evaluate the antimicrobial, antioxidant and cytotoxic activity of their bioactive secondary metabolites. Eight actinomycetes strains were isolated from soil and marine sediment samples collected from different areas in Egypt. Only three actinomycetes exhibited a wide spectrum of antimicrobial activities. They were active in vitro against microbial pathogen viz: Staphylococcus aureus, Escherichia coli, Salmonella typhi, Aspergillus parasiticus, Fusarium solani and Fusarium oxysporum. These promising isolates were selected and identified using molecular identification technique and identified as Streptomyces spp. The crude extracts from the three Streptomyces exhibited potent antimicrobial activities against a set of microbial pathogens as well as antioxidant and anticancer activity in human hepatocellular carcinoma cell line (HepG2). The crude extract of Streptomyces isolate D showed antitumor activity with lC50 0.85 µg/ mL. Forty compounds were identified from the two most promising ethyl acetate extracts of culture broth of Streptomyces sp. (D-EGY) by Gas Chromatography-Mass Spectrometry analysis. It could be concluded that the streptomycetes isolated from the Egyptian environment are promising candidates as antimicrobial, antioxidant and anticancer.The objectives of this study were to isolate and identify the actinomycetes strains from the soil and marine sediments and to evaluate the antimicrobial, antioxidant and cytotoxic activity of their bioactive secondary metabolites. Eight actinomycetes strains were isolated from soil and marine sediment samples collected from different areas in Egypt. Only three actinomycetes exhibited a wide spectrum of antimicrobial activities. They were active in vitro against microbial pathogen viz: Staphylococcus aureus, Escherichia coli, Salmonella typhi, Aspergillus parasiticus, Fusarium solani and Fusarium oxysporum. These promising isolates were selected and identified using molecular identification technique and identified as Streptomyces spp. The crude extracts from the three Streptomyces exhibited potent antimicrobial activities against a set of microbial pathogens as well as antioxidant and anticancer activity in human hepatocellular carcinoma cell line (HepG2). The crude extract of Streptomyces isolate D showed antitumor activity with lC50 0.85 µg/ mL. Forty compounds were identified from the two most promising ethyl acetate extracts of culture broth of Streptomyces sp. (D-EGY) by Gas Chromatography-Mass Spectrometry analysis. It could be concluded that the streptomycetes isolated from the Egyptian environment are promising candidates as antimicrobial, antioxidant and anticancer

Assessment of antimycotoxigenic and antioxidant activity of star anise (Illicium verum) in vitro

In recent years scientists have focused on the identification and the application of natural products for inactivation of mycotoxins. Essential oils with antimicrobial properties are probably the most promising method for the prevention of potentially toxigenic fungi. Thus the aim of this work is to characterise star anise (Illicium verum) and to assess its antioxidant and antifungal and antimycotoxigenic properties using different methods. Results revealed that the major components of star anise essential oil identified by GC/MS were trans-anethole (82.7%), carryophyllene (4.8%) and limonene (2.3%). Total phenolics of ethanol and methanol extracts recorded 112.4 and 96.3 mg GAE/g DW respectively, whereas higher total flavonoid content was recorded for the ethanol extract than the methanol extract. Star anise essential oil showed lower antioxidant activity (55.6 mg/mL) than the extracts using DPPH-scavenging and β-carotene/linoleic acid assays. Results revealed growth reduction of Aspergillus flavus, Aspergillus parasiticus and Fusarium verticillioides by 83.2%, 72.8% and 65.11%, respectively when using 100 ppm of the star anise essential oil, where a complete inhibition was achieved at 200 ppm for A. flavus and A. parasiticus respectively. Aflatoxin B1 and Fumonisin B1 production were inhibited completely at 100 and 200 ppm respectively. It could be concluded that star anise extracts could be considered an important substance that should be explored for the discovery and development of newer and safer food supplements as well as drug products

Extraction and characterization of bioactive secondary metabolites from lactic acid bacteria and evaluating their antifungal and antiaflatoxigenic activity

Aflatoxins are toxic carcinogens and mutagens formed by some moulds, specifically Aspergillus spp. Therefore, this study aimed to extract and identify bioactive secondary metabolites from Lactobacillus species, to evaluate their efficacy in reducing fungal growth and aflatoxin production and to investigate their toxicity. The bioactive secondary metabolites of Lactobacillus species showed variable degrees of antifungal activity, whereas L. rhamnosus ethyl acetate extract No. 5 exhibited the highest antifungal activity and, thus, was selected for further identification studies. Data revealed that L. rhamnosus ethyl acetate extract No. 5 produced various organic acids, volatile organic compounds and polyphenols, displayed antifungal activity against A. flavus, and triggered morphological changes in fungal conidiophores and conidiospores. L. rhamnosus ethyl acetate extract No. 5 at a 9 mg/mL concentration reduced AFB1 production by 99.98%. When the effect of L. rhamnosus ethyl acetate extract No. 5 on brine shrimp mortality was studied, the extract attained a 100% mortality at a concentration of 400 µg/mL, with an IC50 of 230 µg/mL. Meanwhile, a mouse bioassay was performed to assess the toxicity of L. rhamnosus ethyl acetate extract No. 5, whereas there were no harmful effects or symptoms in mice injected with L. rhamnosus ethyl acetate extract at concentrations of 1, 3, 5, 7, and 9 mg/kg body weight

Molecular identification of actinomycetes with antimicrobial, antioxidant and anticancer properties

The objectives of this study were to isolate and identify the actinomycetes strains from the soil and marine sediments and to evaluate the antimicrobial, antioxidant and cytotoxic activity of their bioactive secondary metabolites. Eight actinomycetes strains were isolated from soil and marine sediment samples collected from different areas in Egypt. Only three actinomycetes exhibited a wide spectrum of antimicrobial activities. They were active in vitro against microbial pathogen viz: Staphylococcus aureus, Escherichia coli, Salmonella typhi, Aspergillus parasiticus, Fusarium solani and Fusarium oxysporum. These promising isolates were selected and identified using molecular identification technique and identified as Streptomyces spp. The crude extracts from the three Streptomyces exhibited potent antimicrobial activities against a set of microbial pathogens as well as antioxidant and anticancer activity in human hepatocellular carcinoma cell line (HepG2). The crude extract of Streptomyces isolate D showed antitumor activity with lC50 0.85 µg/ mL. Forty compounds were identified from the two most promising ethyl acetate extracts of culture broth of Streptomyces sp. (D-EGY) by Gas Chromatography-Mass Spectrometry analysis. It could be concluded that the streptomycetes isolated from the Egyptian environment are promising candidates as antimicrobial, antioxidant and anticancer

Synthesis and characterization of cobalt ferrites nanoparticles with cytotoxic and antimicrobial properties

International audienceRecently, the application of nanotechnology in food sector and the agriculture attract the attention compared to its biomedical application. The aims of the current study was to synthesize and characterize cobalt ferrites nanoparticles [(CoFe2O4) NPs] by combustion method employing glycine as fuels and to evaluate their antimicrobial against pathogenic bacteria and fungi and anti cancer properties against MCF-7 breast cancer cells line. The results indicated that the particles size of the synthesized (CoFe2O4) NPs was 40 nm. These (CoFe2O4) NPs showed potential antibacterial properties against Gram-negative bacteria (Escherichia coli, Salmonella typhi) and Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus) as well as the pathogenic fungi (Aspergillus flavus and Aspergillus ochraceus) in a dose dependent manner with maximum concentration of 1.8 mg/ml. (CoFe2O4) NPs also showed weak antiradical but have cytotoxic effects against MCF-7 breast cancer cells line and succeeded to decrease the cell viability at a concentration of 2 mg/ml. It could be concluded that (CoFe2O4) NPs is a promise candidate as antimicrobial and anticancer agent for food sector and medical application

Bioactive compounds from Aspergillus niger extract enhance the antioxidant activity and prevent the genotoxicity in aflatoxin B1-treated rats

This study aimed to identify the bioactive compounds of the ethyl acetate extract of Aspergillus niger SH2-EGY using GC-MS and to evaluate their protective role against aflatoxin B1 (AFB1)-induced oxidative stress, genotoxicity and cytotoxicity in rats. Six groups of male Sprague-Dawley rats were treated orally for 4 weeks included the control group, AFB1-treated group (80 μg/kg b.w); fungal extract (FE)-treated groups at low (140) or high dose (280) mg/kg b.w and the groups treated with AFB1 plus FE at the two tested doses. The GC-MS analysis identified 26 compounds. The major compounds found were 1,2,3,4,6-Penta-trimethylsilyl Glucopyranose, Fmoc-L-3-(2-Naphthyl)-alanine, D-(-)-Fructopyranose, pentakis (trimethylsilyl) ether, bis (2-ethylhexyl) phthalate, trimethylsilyl ether-glucitol, and octadecanamide, N-(2- methylpropyl)-N-nitroso. The in vivo results showed that AFB1 significantly increased serum ALT, AST, creatinine, uric acid, urea, cholesterol, triglycerides, LDL, carcinoembryonic antigen, alpha-fetoprotein, interleukin-6, Malondialdehyde, nitric oxide, Bax, caspase-3 and P53 mRNA expression, chromosomal aberrations and DNA fragmentation. It decreased serum TP, albumin, HDL, Bcl-2 mRNA expression, hepatic and renal TAC, SOD and GPx content and induced histological changes in the liver and kidney. FE prevented these disturbances in a dosage-dependent manner. It could be concluded that A. niger SH2-EGY extract is safe a promising agent for pharmaceutical and food industries