rosmarinic-acid and epigallocatechin-gallate

A simple NMR method to analyze the data obtained by NMR titration experiment of amyloid formation inhibitors against uniformly

Topics: Amyloid; Amyloid beta-Peptides; Catechin; Cinnamates; Curcumin; Depsides; Escherichia coli; Humans; Magnetic Resonance Spectroscopy; Nitrogen Isotopes; Phenols; Principal Component Analysis; Protein Conformation; Rosmarinic Acid; Temperature; Thermodynamics

Interactions between bacterial cells and contact materials play an important role in food safety and technology. As bacterial strains become ever more resistant to antibiotics, the aim of this study was to analyse adhesion of selected foodborne bacterial strains on polystyrene surface and to evaluate the effects of natural antimicrobials on bacterial cell hydrophobicity, adhesion, and zeta potential as strategies of adhesion prevention. The results showed strain-specific adhesion rate on polystyrene. The lowest and the highest adhesion were found for two B. cereus lines. Natural antimicrobials ferulic and rosmarinic acid substantially decreased adhesion, whereas the effect of epigallocatechin gallate was neglectful. Similar results were found for the zeta potential, indicating that natural antimicrobials reduce bacterial adhesion. Targeting bacterial adhesion using natural extracts we can eliminate potential infection at an early stage. Future experimental studies should focus on situations that are as close to industrial conditions as possible.

Topics: Anti-Infective Agents; Bacillus cereus; Bacterial Adhesion; Catechin; Cinnamates; Coumaric Acids; Depsides; Food Contamination; Food Safety; Gram-Negative Bacteria; Gram-Positive Bacteria; Hydrophobic and Hydrophilic Interactions; Polystyrenes; Rosmarinic Acid

Epigallocatechin gallate (EGCG), ellagic acid (EA) and rosmarinic acid (RA) are natural polyphenols exerting cancer chemopreventive effects. Ribonucleotide reductase (RR; EC 1.17.4.1) converts ribonucleoside diphosphates into deoxyribonucleoside diphosphates being essential for DNA replication, which is why the enzyme is considered an excellent target for anticancer therapy. EGCG, EA, and RA dose-dependently inhibited the growth of human HL-60 promyelocytic leukemia cells, exerted strong free radical scavenging potential, and significantly imbalanced nuclear deoxyribonucleoside triphosphate (dNTP) concentrations without distinctly affecting the protein levels of RR subunits (R1, R2, p53R2). Incorporation of (14)C-cytidine into nascent DNA of tumor cells was also significantly lowered, being equivalent to an inhibition of DNA synthesis. Consequently, treatment with EGCG and RA attenuated cells in the G0/G1 phase of the cell cycle, finally resulting in a pronounced induction of apoptosis. Sequential combination of EA and RA with the first-line antileukemic agent arabinofuranosylcytosine (AraC) synergistically potentiated the antiproliferative effect of AraC, whereas EGCG plus AraC yielded additive effects. Taken together, we show for the first time that EGCG, EA, and RA perturbed dNTP levels and inhibited cell proliferation in human HL-60 promyelocytic leukemia cells, with EGCG and RA causing a pronounced induction of apoptosis. Due to these effects and synergism with AraC, these food ingredients deserve further preclinical and in vivo testing as inhibitors of leukemic cell proliferation.

Topics: Adenosine Triphosphate; Antineoplastic Agents; Catechin; Cell Proliferation; Cinnamates; Cytarabine; Depsides; DNA; Drug Synergism; Ellagic Acid; Free Radical Scavengers; HL-60 Cells; Humans; Molecular Structure; Nucleic Acid Synthesis Inhibitors; Rosmarinic Acid; Thymine Nucleotides

Rosmarinic acid and Epigallocatechin gallate concentrations were studied as natural inhibitors of Maillard browning in glucose/glycine model systems, and in bakery rolls and applesauce. The concentrations of the inhibitors were varied to determine the highest level of inhibition without a pro-oxidant/browning effect. UV absorbance and gas chromatography/mass spec (GC/MS) with solid phase microextraction (SPME) sampling was used to study browning in the model systems. Hunter L*, a*, b* was used to analyze the color change results of the inhibitors on applesauce and bakery rolls. It was determined that a 1.0% solution of either antioxidant in the glucose/glycine system produced the greatest inhibition and a synergistic effect was not apparent when the two were combined. Inhibition of browning and a lack of synergy between the antioxidants were also determined in food systems consisting of applesauce and bakery rolls. GC/MS analysis of the model system revealed a high level of pyrazine formation in no-inhibitor control samples and the absence of pyrazines in inhibitor-containing samples.. Natural browning inhibitors, that is Rosmarinic acid and Epigallocatechin gallate, can be added to food items to inhibit browning over a prolonged period of storage in order to increase product shelf stability. The concentrations of the inhibitors require optimization since a pro-oxidant effect and increased browning will occur at high levels.

Topics: Antioxidants; Bread; Catechin; Cinnamates; Color; Depsides; Food Handling; Food Preservation; Fruit; Glucose; Glycine; Humans; Maillard Reaction; Malus; Reactive Oxygen Species; Rosmarinic Acid

One of the methods of increasing the quality of fatty products is including in their composition antioxidants, which provide the time of their conservation and improvement of their biological value. From this point of view calls concern a new drug epigallocatechina gallate. On the basis of these studies the prospects of usage were shown epigallocatechina gallate in fatty products and the paths of further applying in creation of food products.

Topics: alpha-Tocopherol; Antioxidants; Ascorbic Acid; Butylated Hydroxyanisole; Catechin; Cinnamates; Depsides; Dietary Fats; Emulsions; Food Preservation; Plants; Rosmarinic Acid; Soybean Oil