Comparative DNA profiling, botanical identification and biological evaluation of Gazania longiscapa DC and Gazania rigens L.

Gazania longiscapa DC and Gazania rigens L. are species of cultivated ornamental plant that grow in Egypt. Genus Gazania has a role in folk medicine to prevent toothache; this study presents a comparative investigation of genetic and botanical features of root, rhizome, leaves and flowers of the two Gazania species and comparing their biological activity as analgesic and antiinflammatory as related to their folk medicinal use. The genetic and botanical differences between the two Gazania species are reported for the first time in this study. The results contribute toward validation of the traditional use of Gazania showing that both species are safe for oral administration and they exhibit significant antinociceptive and anti-inflammatory effects in a dose dependent manner

Hepatoprotection and Antioxidant Activity of Gazania Longiscapa and G. Rigens with the Isolation and Quantitative Analysis of Bioactive Metabolites

Gazania longiscapa and G. rigens are two species belonging to family Asteraceae. The present study aimed the isolation of the main active constituents from the methanol extracts using different chromatographic methods and their identification using different spectroscopic techniques, beside the quantitation of some biologically important active constituent as rutin using HPLC technique, together with estimation of total polyphenolic content calculated as gallic acid and estimation of total flavonoid content calculated as rutin using UV technique. Concomitantly the determination of the antioxidant and hepatoprotective activity of the total methanol extracts of the aerial parts of G. longiscapa and G. rigens. This work resulted in the isolation of 4 flavonoids (Apigenin, Luteolin, Luteolin 7-O-β-D-glucopyranosid, Apigenin 7-O-β-Dglucopyranosid), 3 phenolic acids (Caffeic acid, Chlorogenic acid and 3,5- di- O-caffeoylquinic acid) from G. longiscapa for the first time; these 3 phenolic acids were also isolated from G. rigens, together with one flavonoid (rutin), The quantitative determination of the methanol extracts showed that G. longiscapa is a richer source of phenolic acids than G. rigens and both Gazania species are valuable sources of rutin beside having hepatoprotective and antioxidant activity

Oxidation characteristics of porous-nickel prepared by powder metallurgy and cast-nickel at 1273 K in air for total oxidation time of 100 h

The oxidation behavior of two types of inhomogeneous nickel was investigated in air at 1273 K for a total oxidation time of 100 h. The two types were porous sintered-nickel and microstructurally inhomogeneous cast-nickel. The porous-nickel samples were fabricated by compacting Ni powder followed by sintering in vacuum at 1473 K for 2 h. The oxidation kinetics of the samples was determined gravimetrically. The topography and the cross-section microstructure of each oxidized sample were observed using optical and scanning electron microscopy. X-ray diffractometry and X-ray energy dispersive analysis were used to determine the nature of the formed oxide phases. The kinetic results revealed that the porous-nickel samples had higher trend for irreproducibility. The average oxidation rate for porous- and cast-nickel samples was initially rapid, and then decreased gradually to become linear. Linear rate constants were 5.5 × 10−8 g/cm2 s and 3.4 × 10−8 g/cm2 s for the porous- and cast-nickel samples, respectively. Initially a single-porous non-adherent NiO layer was noticed on the porous- and cast-nickel samples. After a longer time of oxidation, a non-adherent duplex NiO scale was formed. The two layers of the duplex scales were different in color. NiO particles were observed in most of the pores of the porous-nickel samples. Finally, the linear oxidation kinetics and the formation of porous non-adherent duplex oxide scales on the inhomogeneous nickel substrates demonstrated that the addition of new layers of NiO occurred at the scale/metal interface due to the thermodynamically possible reaction between Ni and the molecular oxygen migrating inwardly