412 research outputs found

    Seven naphtho-γ-pyrones from the marine-derived fungus Alternaria alternata: structure elucidation and biological properties

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    Eight bioactive pyrone derivatives were identified from the culture of Alternaria alternata strain D2006, isolated from the marine soft coral Denderonephthya hemprichi, which was selected as its profound antimicrobial activities. The compounds were assigned as pyrophen (1), rubrofusarin B (2), fonsecin (3), and fonsecin B (5) beside to the four dimeric naphtho-γ-pyrones; aurasperone A (6), aurasperone B (7), aurasperone C (8), and aurasperone F (9). Structures of the isolated compounds were identified on the basis of 1D and 2D NMR spectroscopy and mass (EI, ESI, HRESI) data, and by comparison with the literature. Configuration of the four dimeric naphtho-γ-pyrones 6-9 was analyzed by CD spectra, exhibiting an identical stereochemistry

    Hydrolytic and chromatographic studies on the PEGylation of dextranase from Penicillium sp.

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    AbstractDextranases catalyze the hydrolysis of the α-l,6-glucosidic bond of the polysaccharide dextran. Dextranases have been isolated from bacteria, yeast and fungi. Purified dextranase enzyme from Penicillium sp. was PEGylated (polyethylene glycol modification) with mPEG (5000Da) and showed an increase in the dextranase protein molecular weight as estimated by Superose 12 (23ml) column and this increment in the molecular weight is directly proportional to mPEG (5000Da) concentration until a complete dextranase enzyme PEGylation (disappearance of dextranase peak). The residual activity of partially PEGylated dextranase (mPEG 5000 of 5.8mg/ml) was 33.8% and for the completely PEGylated dextranase (mPEG 5000 of 29mg/ml) it was 25.75%. Dextranase PEGylated with mPEG (30,000Da) showed a little PEGylation at mPEG concentration of 5.8mg/ml but at a concentration of 29mg/ml several PEGylated peaks were produced with a difference in dextranase activity toward dextran T500, retardation in the activity with the increasing in the molecular weight was clearly appeared with Sephadex G75 but for Sephadex G200 a little retardation than Sephadex G75 has been appeared

    On Dual Curves of DAW(k)-Type and Their Evolutes

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    In this paper, we study to express the theory of curves including a wide section of Euclidean geometry in terms of dual vector calculus which has an important place in the three -dimensional dual space D3\mathbb{D}^{3}. In other words, we study DAW(k)DAW(k)-type curves (1k3)\left( 1\leq k\leq 3\right) by using Bishop frame defined as alternatively of these curves and give some of their properties in D3\mathbb{D}^{3}. \ Moreover, we define the notion of evolutes of dual spherical curves for ruled surfaces. Finally, we give some examples to illustrate our findings

    Molecular identification of actinomycetes with antimicrobial, antioxidant and anticancer properties

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    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

    Anti-Obesity Evaluation of Averrhoa carambola L. Leaves and Assessment of Its Polyphenols as Potential α-Glucosidase Inhibitors

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    Averrhoa carambola L. is reported for its anti-obese and anti-diabetic activities. The present study aimed to investigate its aqueous methanol leaf extract (CLL) in vivo anti-obese activity along with the isolation and identification of bioactive compounds and their in vitro α-glucosidase inhibition assessment. CLL improved all obesity complications and exhibited significant activity in an obese rat model. Fourteen compounds, including four flavone glycosides (1–4) and ten dihydrochalcone glycosides (5–12), were isolated and identified using spectroscopic techniques. New compounds identified in planta included (1) apigenin 6-C-(2-deoxy-β-D-galactopyranoside)-7-O-β-D-quinovopyranoside, (8) phloretin 3′-C-(2-O-(E)-cinnamoyl-3-O-β-D-fucopyranosyl-4-O-acetyl)-β-D-fucopyranosyl-6′-O-β-D fucopyranosyl-(1/2)-α-L arabinofuranoside, (11a) phloretin3′-C-(2-O-(E)-p-coumaroyl-3-O-β-D-fucosyl-4-O-acetyl)-β-D-fucosyl-6′-O-(2-O-β-D-fucosyl)-α-L-arabinofuranoside, (11b) phloretin3′-C-(2-O-(Z)-p-coumaroyl-3-O-β-D-fucosyl-4-O-acetyl)-β-D-fucosyl-6′-O-(2-O-β-D-fucosyl)-α-L-arabinofuranoside. Carambolaside M (5), carambolaside Ia (6), carambolaside J (7), carambolaside I (9), carambolaside P (10a), carambolaside O (10b), and carambolaside Q (12), which are reported for the first time from A. carambola L. leaves, whereas luteolin 6-C-α-L-rhamnopyranosyl-(1-2)-β-D-fucopyranoside (2), apigenin 6-C-β-D-galactopyranoside (3), and apigenin 6-C-α-L-rhamnopyranosyl-(1-2)-β-L-fucopyranoside (4) are isolated for the first time from Family. Oxalidaceae. In vitro α-glucosidase inhibitory activity revealed the potential efficacy of flavone glycosides, viz., 1, 2, 3, and 4 as antidiabetic agents. In contrast, dihydrochalcone glycosides (5–11) showed weak activity, except for compound 12, which showed relatively strong activity

    Human microbiome and its association with health and diseases

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    Human microbiota are distinct communities of microorganisms that resides at different body niches. Exploration of the human microbiome has become a reality due to the availability of powerful metagenomics and metatranscriptomic analysis technologies. Recent advances in sequencing and bioinformatics over the past decade help provide a deep insight into the nature of the host-microbial interactions and identification of potential deriver genes and pathways associated with human health, well-being, and predisposition to different diseases. In the present review, we outline recent studies devoted to elucidate the possible link between the microbiota and various type of diseases. The present review also highlights the potential utilization of microbiota as a potential therapeutic option to treat a wide array of human diseases

    Anti-prostate cancer metabolites from the soil-derived Aspergillus neoniveus

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    Prostate cancer (PCa) ranks as one of the most commonly diagnosed malignancies worldwide. Toxicity, lack of clinical efficacy, and development of resistance phenotypes are the main challenges in the control of prostate malignancies. Notably, castration-resistance prostate cancer (CRPCa) is a highly aggressive and metastatic phenotype of the disease with a poor prognosis and very limited therapeutic options. Herein, we report the isolation and genotypic identification of a soil-derived fungus Aspergillus neoniveus using the PCR-based internal transcribed spacer (ITS) region amplification approach. HPLC/MS investigation of the metabolic profile of the ethyl acetate extract from the fungal biomass revealed tentative identification of forty-five compounds belonging to various chemical classes including γ-butyrolactones, alkaloids, phenolics, and quinoids. Furthermore, the chromatographic purification of microbial extract enabled the identification of nervonic acid methyl ester (1) for the first time from endophytic fungi, as well as acetyl aszonalenin (2), and butyrolactone II (3) for the first time from A. neoniveus. The chemical frameworks of the isolated compounds were identified via extensive spectral analysis including 1 and 2D NMR and MS. The X-ray crystal structure and absolute configuration of acetyl aszonalenin (2) were also determined. Additionally, screening of in vitro anticancer activity of the fungal extract revealed its potential antiproliferative and anti-migratory activities against five different prostate cancer cells (PC3, PC-3M, DU-145, CWR-R1ca, and 22Rv1), including different cells with the castration-resistance phenotype. Moreover, the isolated metabolites significantly inhibited the proliferation, migration, and colonization of human prostate cancer cells at low micromolar levels, thus providing credence for future investigation of these metabolites in relevant anti-prostate cancer animal models. Furthermore, computational target prediction tools identified the cannabinoid G-protein coupled receptors type 1 (CB1) as a potential biological target mediating, at least in part, the anticancer effects of acetylaszonalenin (2). Moreover, molecular modeling and docking studies revealed a favorable binding pose at the CB1 receptor orthosteric ligand pocket aided by multiple polar and hydrophobic interactions with critical amino acids. In conclusion, the Aspergillus neoniveus-derived prenylated indole alkaloid acetylaszonalenin has promising anticancer activity and is amenable to further hit-to-lead optimization for the control of prostate malignancies via modulating CB1 receptor
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