M. P. Nawiri

Fabrication of metal oxide - biopolymer nanocomposite for water defluoridation

Fluoride contamination in groundwater affects about 150 million people worldwide. In this study, the authors focused on synthesizing biopolymer metal oxide nanocomposite for fluoride removal. Nanocomposite material was done using SEM. As(V), Al, Ti, Zr, and Fe water samples were analysed by ICP-MS (inductively coupled plasma-mass spectrometry). Fluoride level was determined using the standard method – Ion-Selective Electrode method. Preliminary results indicate arsenic (V) removal was below the 10 ppb and fluoride less than 1.5 ppm as prescribed by WHO. The removal efficiency was after 60-70 minutes with recyclability of 11 cycles. The nanocomposite worked well in all pH ranges 6.5-8.5. A filter cartridge biopolymer metal oxide nanocomposite constituting of template aluminium homogenized in the aggregated network of chitosan was developed as an adsorbent for fluoride from the water with better adsorption limit. Fabrication of Metal OxideBiopolymer Nanocomposite for Water Defluoridation

Water Stress Effect on Total Antioxiant Activity and Total Phenolic Content of Solanum scabrum Mill and Solanum scabrum in Kiambu, Kenya

Aims: The aims of this study were to investigate water stress effect on total phenolics and total antioxidants of selected African nightshades and determine any possible variations in the amount of total phenolics and total antioxidants among the accessions grown. Study Design: Study was conducted on the basis of randomized complete block design. Place and Duration of Study: The study was carried out in Kenyatta University Agricultural farm in Kiambu County of Kenya. Greenhouse experiments were carried out in the same farm. Methodology: A greenhouse and field experiment was conducted to investigate effects of water stress on total phenolic and total antioxidant contents of Solanum scabrum and Solanum villosum. The two African nightshades were subjected to different soil water tensions of 15cbars, 50cbars and 85cbars. After a month of transplanting, samples from the different blocks were collected fortnightly and prepared for total phenolic and total antioxidant determination. Short Research Article Okello et al.; IJBCRR, 17(1): 1-9, 2017; Article no.IJBCRR.33715 2 Results: Obtained data showed that Solanum villosum had a higher concentration of both the total phenolics and antioxidant activity in the shoots (46.41 g/Kg total phenolic content and 52.68% total antioxidant activity) while Solanum scabrum had higher concentration in the roots (25.06 g/Kg total phenolic content and 27.18% total antioxidant activity). Conclusion: Total phenolics and total antioxidant accumulation not only depend on irrigation variation but also on the accessions grown.

Essential Antioxidant Elements in Oils of the Cake and Shell of Calodendrum capense Nuts

Abstract Increasing deaths due to skin cancer have been attributed to the sun’s ultra-violet (UV) radiations which initiate free radical reactions. Synthetic sunscreens contain antioxidants that prevent the free radical effects but risk skin exposure to harmful synthetic compounds of Cu, Mg, Mn and Zn. Calodendrum capense nut oil (cape chestnut or yangu oil), popular for African skin care is destined for natural cosmetic. Literature is scarce on the antioxidant element composition of its oil. We report the levels of Cu, Mg, Mn and Zn in oil from two parts of the nuts; cake and shells measured by AAS. Results show the potential supply of Cu, Mg, Mn and Zn from yangu oil of the two parts of the nuts that can serve as a physical sun-block. The use of yangu oil for skin protection against UV radiations is encouraged.