The effects of the addition of poly(4-vinylpyridine) (P4VP) and its derivative poly(4-vinylpyridine poly-3-oxide ethylene) (P4VPPOE) on the corrosion of Cu60-Zn40 in 0.5M HNO 3 have been investigated by potentiodynamic and weight loss measurements. Both of the studied polymers decrease the corrosion rate. Their inhibition efficiency (E%) increases with the concentration. The maximum of inhibition was obtained for P4VPPOE (100 per cent at 10 ±5 M). E% obtained from cathodic Tafel plots and weight loss methods were in good agreement. The inhibitors were adsorbed on the Cu60-Zn40 surface according to the Frumkin adsorption isotherm model. P4VPPOE acts as a cathodic inhibitor and its efficiency is temperature independent.
Introduction: Oxidative stress is involved in many pathological mechanisms especially those due to aging, such as cancer, Parkinson's and Alzheimer's disease. Essential oils are known for their biological properties, especially as anti-nociceptive, anticancer, antiviral and antioxidative. The main objective of this study was to study the antioxidant activity of essential oils from Thymus fontanesii, Artemisia herba-alba and Rosmarinus officinalis, individually and in combinations. Materials and Methods: Essential oils of plants aerial parts were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The antioxidant properties were evaluated using two different methods, α, α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP). Results: The essential oil of T. fontanesii was principally characterized by phenolic compounds represented by thymol (76.6%) and p-cymene (7.4%). The constituents identified from A. herba-alba essential oil were principally represented by camphor (32.3%) and chrysanthenone (25.6%). While, R. officinalis essential oil was characterized by 1,8-cineole (18.3%), camphene (15.4%) and α-pinene (12.8%). T. fontanesii essential oil indicated the significantly highest activity in quenching of DPPH radical, followed by R. officinalis and A. herba-alba essential oils with IC 50 of 13.7, 24.5 and 79.4 mg/L, respectively. The combination of T. fontanesii, A. herba-alba and R. officinalis essential oils showed the greatest antioxidant activity with an IC 50 of 2.6 mg/L almost equal to the synthetic antioxidant butylated hydroxytoluene (BHT). Conclusions: The essential oils blend presented high antioxidant activity compared to individual oils. These findings provide a new source of antioxidant that can be used as a natural food preservative and alternative to chemical synthetic preservatives.
Seeds of melon (Cucumis melo L. Inodorus) were analyzed for their mineral and lipid compositions. The seeds showed a 30.7%lipids content and ashes accounted for 4.08%. Freshly extracted oil showed acid and peroxide values respectively 4.01 mg KOH/g and 2.25Meq (O 2)/Kg. Iodine and saponification values were 104.52 g (I 2)/100 g and 193.60 mg (KOH)/g respectively. Main fatty acids identified so far were linoleic, oleic, palmitic and stearic acids with respective contents 60.
This study investigated the underlying mechanism of 4-hydroxy-3-methoxycinnamic acid (ACCA), on the growth of breast cancer cells and normal immortal epithelial cells, and compared their cytotoxic effects responses. Treatment of breast cancer cells (MCF-7, T47D, and MDA-231) with ACCA resulted in dose- and time-dependent decrease of cell proliferation, viability in colony formation assay, and programmed cell death (apoptosis) with minimal effects on non-tumoral cells. The ability of ACCA to suppress growth in cancer cells not expressing or containing defects in p53 gene indicates a lack of involvement of this critical tumor suppressor element in mediating ACCA-induced growth inhibition. Induction of apoptosis correlated with an increase in Bax protein, an established inducer of programmed cell death, and the ratio of Bax to Bcl-2, an established inhibitor of apoptosis. We also documented the ability of ACCA to inhibit the migration and invasion of MDA-231 cells with ACCA in vitro. Additionally, tumor growth of MDA-231 breast cancer cells in vivo was dramatically affected with ACCA. On the basis of its selective anticancer inhibitory activity on tumor cells, ACCA may represent a promising therapeutic drug that should be further evaluated as a chemotherapeutic agent for human breast cancer.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.