Clematis hirsuta in the family of Ranunculaceae is geographically dispersed in highland areas including Ethiopia. The leaves and roots of Clematis hirsuta is traditionally used to treat various diseases in different regions of Ethiopia. This study is aimed to evaluate the phytochemical constituents, antibacterial and antioxidant activity studies on the crude root extracts of Clematis hirsuta. The air-dried plant sample was powdered, extracted successively with n-hexane, chloroform and methanol. The solid matter was separated by filtration and then filtrates were concentrated using a rotary evaporator. The dried extract was subjected to a preliminary phytochemical screening test using standard procedures and the result showed the presence of alkaloid, saponins, tannins, flavonoids, phenols, glycosides and carbohydrates. Antibacterial activity of the crude extract was determined by using the disc diffusion method. The methanol extract of the roots of Clematis hirsuta showed a significant inhibition zone on all of the selected bacteria (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Salmonella thyphi) while chloroform extract had inhibition on Pseudomonasaeruginosa and Staphylococcus aureus. The methanol crude extract was screened for antioxidant activity by the DPPH assay method. At 2 mg/mL methanol crude extract gave %DPPH inhibition of 98.2% as compared to reference ascorbic acid (95.8%) at the same concentration. This study showed that the roots of Clematis hirsuta constitute phytochemicals that possess antibacterial and antioxidant activities and can serve as a potential source in search of plant-based antibiotics and natural antioxidants.
Traditionally, the leaves of Plumbago Zeylanica were used for the treatment of several diseases. Herein, we report phytochemical analysis, total flavonoid and phenolic content, antioxidant capacity, and antibacterial activities of the leaf extracts of the plant. The phytochemical analysis test of the extracts showed the presence of biologically important compounds such as phenolics, flavonoids, alkaloids, terpenoids, and glycosides. Moreover, the total flavonoid content of 69.566, 66.966, and 59.133 mgQE/100 g was obtained from methanol, ethyl acetate, and petroleum ether extracts respectively. And the total phenolic content of methanol, ethyl acetate, and petroleum ether extracts were 82.738, 69.784, and 51.630 mgGAE/g dry samples. The extracts have promising antioxidant and antibacterial activity against S.aureus (Staphylococcus aureus), S. pyogens (Streptococcus pyogens), E. coli (Escherichia coli), and K. peneumona (Klebsiella pneumonia). The high antibacterial and antioxidant activity was found for methanol extract of the leaf extract of P. Zeylanica is attributing to the presence of polar phytochemicals such as; flavonoids, phenolic, and glycosidic groups in the crude extract obtained from maceration of polar solvents.
This paper reviews recent progress in the fabrication of graphene-based polymer nanocomposites and their applications. The modification of graphene, graphene oxide, reduced graphene oxide and the utilization of these materials in the fabrication of nanocomposites with different polymer matrixes have been explored. The methods for surface modification of Graphene with polymers, including various covalent and non-covalent techniques, are discussed in detail. Series of effective processing routes for producing high-quality G-polymer nanocomposites, such as melt compounding, solution blending, in situ polymerization, latex mixing, and electropolymerization, are introduced and discussed. Various organic polymers have been used to fabricate graphene-filled polymer nanocomposites using different methods. Different characterisation methods and applications of these polymer composites were reviewed.
Total polyphenol, antioxidant activity and heavy metal contents in selected Ethiopian beers (Dashen= B1, Harar = B2, Habesha= B3, Saint George= B4 and Walya= B5) were investigated. The average concentration of total phenolic content in B1, B2, B3, B4 and B5 were found to be 219.80, 206.09, 190.24, 193.00 and 212.10 mg GAE/L, respectively. The obtained results showed that B1 contained significantly highest total polyphenol content (219.80±2.83 mg/L) and showed the highest radical scavenging capacities (84.16±0.65). According to Pearson’s correlation between polyphenol extract with antioxidant activities, suggested that phenolic compound in beer were contributor to antioxidant activity. Similarly, all the beer samples were analyzed for Cd, Cr, Cu, Ni and Pb with flame atomic absorption spectrophotometer. The total metal concentrations of Cd, Cr, Cu Ni and Pb were found to be in the range of (ND–0.022 mg/L), (0.02 -0.041), (0.023-0.054), (ND-0.064) and (ND-0.022 mg/L), respectively. The efficiency of the procedure was validated by spiking and the percent recovery of the metals varied from 90.9-104.3%.
When human is exposed to endocrine-disrupting chemicals (EDCs) such as phthalates, for example, di(2-ethylhexyl) phthalate(DEHP) and diisononyl phthalate (DINP)in early life may contribute to overweight and obesity. EDCs are also called obesogen. Obesogen can promote adipogenesis and cause weight gain. Phthalates are man-made chemicals used in polyvinyl (PVC) products such as wires, cables, floorings, wall coverings, medical devices and cosmetics. The vulnerability of humans to EDCs has resulted in adverse health consequences, including decreased sperm motility, infertility in men, coronary heart disease, high blood pressure, atherosclerosis, and obesity. This paper will educate people all over the world about the danger associated with contact with phthalates. It will also help to make people limit exposure to materials made of phthalates.
