The antibacterial activity of non-Stoichiometric calcium phosphate particles prepared by precipitation under controlled experimental conditions at pH~9 and sintered at high temperature was studied against Staphylococcus aureusbacteria. The effects of operating parameters developed (designed) according to an experimental design of Plackett-Burman typeon the physicochemical characteristics and the capacity to inhibit bacterial growth were identified using a thermal analysis (TGA-DTA-DSC). X-Ray Diffraction (XR), Raman Spectroscopy, Scanning Electron Microscope (SEM) and the Kirby Bauer Method. The XRD spectrum shows that the synthetic crystalline nanoparticles powders consist of multiphasic calcium phosphate ?-TCP/?-CPP/OCP/HA and that the average particle size is between 56 and 123 nm calculated by the Debay-Shearer equation. The Raman spectrum of sintered powder shows the main absorption bands that are assigned to the asymmetric / symmetric P-O stretching vibrations in PO4-3 and the symmetric O-H stretching mode of the hydroxyl groupin addition of Ca-PO4 and Ca-OH modes. The samples were found to possess different morphologies consisting of Nano-rods of different lengths, semi / spherical structures and fine granules, in addition to irregular Clusters. The antibacterial tests results showed that the high concentration calcium phosphate powder exhibited better antibacterial activity against Staphylococcus aureus bacteria with inhibition zones ranging from 0.2-0.7 cm.

Introduction: The brain is one of the most sensitive tissues that lead poisoning affects and the nervous system is at higher risk of lead toxicity. Aim: The aim of study was to investigate the influence of aqueous extract of Ocimum gratissimum (OG) leaves on lead-induced toxicity on the cerebrum of adult Wistar rats. Methods: Thirty five adult Wistar rats were randomly assigned into seven groups of five rats each. Group 1 was the Control, Group 2 was given lead acetate only, Group 3, received 375mg/kg body weight (bwt) of the extract only, Group 4 received 375mg/kgbwt of the extract and lead acetate, Group 5 received 750mg/kgbwt of the extract and lead acetate, Group 6 received 375mg/kgbwt of the extract and then lead acetate while Group 7 was given 1,190 mg/kgbwt of Vit. C and then lead acetate. All the animals received120mg/kgbwt of lead acetate and the administration lasted 21 days through oral route.At the end, the rats were sacrificed, blood was collected for analysis of oxidative stress markers and the brains were removed, fixed, processed and stained for histological studies. Results: The result showed the mean value of Catalase was significantly higher in Group 1 compared to Groups 2, 3and 4 (P?0.05) with a mean value of 13.50�0.50; 9.13�1.05; 11.00�0.27 and 11.83�0.64 respectively. The mean vale of Glutathione in Group 2 (1.20�0.56) showed significant decrease when compared to the Control Group (2.43�0.35) (P?0.05). Histological study revealed normal cerebral cyto-architecture in the granular cell layer of the brain in the Group 1, while the rats inGroup 2, showed marked distortion of the layers of the cerebral cortex, proliferations of glial cells, area of cortical degeneration with fatty necrosis and neuronal degenerations of the cells and the presence of vacuoles. The treated Groups showed regeneration of cerebral tissues and neuronal cells when compared to lead only treated group.Conclusion: The ability of the OG extract to restore the cyto-architecture of the cerebrum and reduce neurodegeneration of cells was dose-dependent which showed that the aqueous extract of OG leaves may be beneficial in the management of lead toxicity involving oxidative stress.