scholarly journals Study on Ajuga reptans Extract: A Natural Antioxidant in Microencapsulated Powder Form as an Active Ingredient for Nutraceutical or Pharmaceutical Purposes

Pharmaceutics ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 671
Author(s):  
Tiziana Esposito ◽  
Francesca Sansone ◽  
Giulia Auriemma ◽  
Silvia Franceschelli ◽  
Michela Pecoraro ◽  
...  
Keyword(s):  
Water Solubility ◽  
Chemical Characterization ◽  
Natural Antioxidants ◽  
Solid Matrix ◽  
Process Yield ◽  
E Coli ◽  
Ajuga Reptans ◽  
Coating Agents

The administration of natural antioxidants is considered to be a prevention strategy for chronic diseases and a useful tool for the healthcare system to reduce the administration of expensive and often not effective treatments. The chemical characterization of a methanolic extract (AJ) of Ajuga reptans L. was performed, and its antioxidant activity was evaluated. AJ and the major compounds, characterized by chromatographic techniques as phenylpropanoids and iridoids, were able to reduce the Reactive Oxygen Species levels in cancer cell lines (melanoma, A375, cervical cancer, HeLa, and alveolar adenocarcinoma, A549), stimulated by E. coli lipopolysaccharide. However, a clinical translation of these results encountered a significant limitation represented by the poor water solubility and bioavailability of the extract and compounds. Consequently, a hydro-soluble powder system (AJEP3) was developed by spray-drying encapsulating AJ into a multi-component solid matrix that is based on L-proline and hydroxyethylcellulose as loading and coating agents, and lecithin as solubility enhancer. The technological approach led to a satisfactory process yield (71.5%), encapsulation efficiency (99.9%), and stability. The in vitro water dissolution rate of the bioactive compounds appeared to be improved with respect to the extract, suggesting higher feasibility in the manufacturing and administration; even the in vitro biological activity of the produced multi-component AJEP3 was clearly enhanced.

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

2019 ◽  
Author(s):  
Priya Prakash ◽  
Travis Lantz ◽  
Krupal P. Jethava ◽  
Gaurav Chopra
Keyword(s):  
Amyloid Beta ◽  
Western Blots ◽  
Force Microscopy ◽  
E Coli ◽  
Atomic Force ◽  
Set Up ◽  
Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

scholarly journals Functional identification of ygiP as a positive regulator of the ttdA-ttdB-ygjE operon

Microbiology ◽  
2006 ◽  
Vol 152 (7) ◽  
pp. 2129-2135 ◽  
Author(s):  
Taku Oshima ◽  
Francis Biville
Keyword(s):  
Functional Characterization ◽  
Anaerobic Growth ◽  
Functional Identification ◽  
New Members ◽  
E Coli ◽  
Inner Membrane Protein ◽  
Tartrate Dehydratase

Functional characterization of unknown genes is currently a major task in biology. The search for gene function involves a combination of various in silico, in vitro and in vivo approaches. Available knowledge from the study of more than 21 LysR-type regulators in Escherichia coli has facilitated the classification of new members of the family. From sequence similarities and its location on the E. coli chromosome, it is suggested that ygiP encodes a lysR regulator controlling the expression of a neighbouring operon; this operon encodes the two subunits of tartrate dehydratase (TtdA, TtdB) and YgiE, an integral inner-membrane protein possibly involved in tartrate uptake. Expression of tartrate dehydratase, which converts tartrate to oxaloacetate, is required for anaerobic growth on glycerol as carbon source in the presence of tartrate. Here, it has been demonstrated that disruption of ygiP, ttdA or ygjE abolishes tartrate-dependent anaerobic growth on glycerol. It has also been shown that tartrate-dependent induction of the ttdA-ttdB-ygjE operon requires a functional YgiP.

Characterization of in vitro and in vivo murine models of human enteropathogenic E. coli (EPEC) infection

2003 ◽  
Vol 124 (4) ◽  
pp. A558
Author(s):  
Suzana D. Savkovic ◽  
Farol L. Tomson ◽  
Michelle Muza ◽  
Gail Hecht
Keyword(s):  
Murine Models ◽  
E Coli

Chemical Characterization of E. coli Capsules and Analysis of their Expression

1991 ◽  
pp. 151-160 ◽  
Author(s):  
Barbara Jann ◽  
Maria-Luisa Rodriguez ◽  
Andreas Finke ◽  
Klaus-Dieter Kröncke ◽  
Klaus Jann
Keyword(s):  
Chemical Characterization ◽  
E Coli

scholarly journals Characterization of MazFSa, an Endoribonuclease from Staphylococcus aureus

2007 ◽  
Vol 189 (24) ◽  
pp. 8871-8879 ◽  
Author(s):  
Zhibiao Fu ◽  
Niles P. Donegan ◽  
Guido Memmi ◽  
Ambrose L. Cheung
Keyword(s):  
Staphylococcus Aureus ◽  
Environmental Stress Response ◽  
Binding Studies ◽  
Cell Growth Arrest ◽  
Consensus Sequences ◽  
E Coli ◽  
Endoribonuclease Activity

ABSTRACT The mazEF homologs of Staphylococcus aureus, designated mazEFsa , have been shown to cotranscribe with the sigB operon under stress conditions. In this study, we showed that MazEF Sa , as with their Escherichia coli counterparts, compose a toxin-antitoxin module wherein MazF Sa leads to rapid cell growth arrest and loss in viable CFU upon overexpression. MazF Sa is a novel sequence-specific endoribonuclease which cleaves mRNA to inhibit protein synthesis. Using ctpA mRNA as the model substrate both in vitro and in vivo, we demonstrated that MazF Sa cleaves single-strand RNA preferentially at the 5′ side of the first U or 3′ side of the second U residue within the consensus sequences VUUV′ (where V and V′ are A, C, or G and may or may not be identical). Binding studies confirmed that the antitoxin MazE Sa binds MazF Sa to form a complex to inhibit the endoribonuclease activity of MazF Sa . Contrary to the system in E. coli, exposure to selected antibiotics augmented mazEFsa transcription, akin to what one would anticipate from the environmental stress response of the sigB system. These data indicate that the mazEF system of S. aureus differs from the gram-negative counterparts with respect to mRNA cleavage specificity and antibiotic stresses.

THE METABOLISM OF ALDOSTERONE BY SURVIVING DOG AND HUMAN LIVER SLICES

1960 ◽  
Vol 38 (1) ◽  
pp. 739-756
Author(s):  
Thomas Sandor ◽  
Wojciech J. Nowaczynski ◽  
Jacques Genest
Keyword(s):  
Human Liver ◽  
Chemical Characterization ◽  
Liver Slices ◽  
Metabolic Products ◽  
Reducing Substances ◽  
Dog Liver ◽  
Human Liver Slices ◽  
Acetate Form

Surviving dog liver slices were incubated with d,l-aldosterone-21-monoacetate, d,l-aldosterone, d-aldosterone, and d-aldosterone-21-C14. Human liver slices were incubated with d,l-aldosterone-21-monoacetate and d-aldosterone. The incubations were performed in a Krebs–Ringer–phosphate medium (pH 7.4), with 200 mg glucose added per 100 ml of medium, at a temperature of 37 °C. After incubation, the medium was extracted with chloroform and the crude extract extensively fractionated on column and paper chromatographic systems. In addition to free aldosterone, four metabolic products were isolated, two ring A reduced α-ketolic and two ultraviolet absorbing, non-reducing substances. The partial chemical characterization of these metabolites was attempted. The search for aldosterone metabolites in human urine resulted in the isolation of a substance in acetate form from the urine of a patient suffering from primary aldosteronism which may be identical with one of the ring A reduced metabolites obtained in the in vitro experiments.

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