ABSTRACT
Aims: This work is aimed at investigating physicochemical parameters and compositions of fatty acid, phospholipid and sterol of desert date (Balanites aegyptiaca) kernel and pulp. Study Design: Balanites aegyptiaca fruit is one of the oldest feed-stocks in Africa of which little or no attention has been given to it. The plant plays a diverse cultural and traditional role in different societies. Therefore, it is very important to explore more about the chemical composition of the kernel and pulp oils of Balanites aegyptiaca; since it is currently attracting considerable research interest as a result of its diverse beneficial properties. Methodology: The physicochemical parameters, fatty acids, phospholipids and phytosterols of B. aegyptiaca seed and pulp oils have been analyzed and compared with the standards and that of conventional oil for easy assessment of their suitability for nutritional and industrial applications. Results: The results of some physicochemical parameters of kernel and pulp oils were acid value (26.35 and 15.60 mg KOH/g), peroxide value (3.82 and 5.90 meq/kg), saponification value (162.40 and 198.60 mg KOH/g), iodine value (55.20 and 142.50 mg of I/100 g), specific gravity (0.93 and 0.92), kinematic viscosity (2.12 and 1.65 St) and refractive index (1.41 and 1.39), respectively. The most concentrated fatty acids were palmitic acid (14.53%) < linoleic acid (35.65%) < oleic acid (38.27%) for the kernel oil while that of pulp oil were linolenic acid (8.21%) < oleic acid (16.80%) < palmitic acid (32.70%) < linoleic acid (33.56%). Arachidic, behenic, lignoceric and myristic acids were all present in small quantities with none of them recording up to 1.0% in either of the samples. Caprylic, capric and lauric acids were determined but not detected in both oils. The fatty acid composition of kernel and pulp oils contained a healthy mixture of all the types of saturated and unsaturated fatty acids. The value of polyunsaturated/saturated index (P/S) which is associated to the impact on human health was higher in the pulp oil (2.47). Phosphatidylcholine had the highest content in both oils that is 75.99 and 25.88 mg/100 g, respectively. The total values of phytosterols for kernel and pulp oils were 85.00 and 9.87 mg/100 g, respectively. Conclusion: Balanites aegytiaca kernel and pulp oils have the potential to substitute several materials used in manufacturing oil in the chemical and pharmaceutical industries. However, in order to extend usage, these oils should be refined in order to improve the colour and taste.
ABSTRACT
ABSTRACT: This study evaluated the bioremediation of atrazine herbicide contaminated agricultural soil under different bioremediation strategies using indigenous Pseudomonas aeruginosa, Bacillus subtilis and Aspergillus niger as bioaugmentation agents and poultry droppings as biostimulation agent. The results showed that bioaugmentation with Pseudomonas aeruginosa, bioaugmentation with Bacillus subtilis, bioaugmentation with Aspergillus niger, bioaugmentation with bacterial-fungal consortium (Pseudomonas aeruginosa, Bacillus subtilis and Aspergillus niger), biostimulation with poultry droppings, and combined biougmentation and biostimulation (Pseudomonas aeruginosa, Bacillus subtilis, Aspergillus niger and poultry droppings) resulted in maximum atrazine biodegradation of about 97%, 95%, 84%, 99%, 100% and 100%, respectively. The kinetics of atrazine biodegradation in the soil were modelled using first-order kinetic model and the biodegradation half-life estimated. The first order kinetic model adequately described the kinetics of atrazine biodegradation in soil under the different bioremediation strategies. The rate constants ( k1 ) of atrazine biodegradation in soil subjected to bioaugmentations with Pseudomonas aeruginosa, Bacillus subtilis, Aspergillus niger, and bacterial-fungal consortium ranges between 0.059 day-1 and 0.191 day-1 while for that subjected to natural bioattenuation, biostimulation and combined bioaugmentation and biostimulation are 0.026 day-1, 0.164 day- 1 and 0.279 day-1, respectively. The half-life ( 2 t1/ ) of atrazine biodegradation in soil under natural bioattenuation was obtained to be 26.7 days. This was reduced to between 2.5 and 11.7 days under the application of bioaugmentation, biostimulation and combined bioaugmentation and biostimulation strategies. The bioremediation efficiencies of the different bioremediation strategies in influencing atrazine biodegradation or removal is of the following order: Combined bioaugmentation and biostimulation > Bioaugmentation with bacterial-fungal consortium > Biostimulation with poultry droppings > Bioaugmentation with Pseudomonas aeruginosa > Bioaugmentation with Bacillus subtilis > Bioaugmentation with Aspergillus niger > Natural bioattenuation
Subject(s)
Atrazine , Biodegradation, Environmental/methods , NigeriaABSTRACT
This study was aimed to investigate the use of pineapple as a cheap, eco-friendly adsorbent and support matrix for the immobilization of microbial cell and for subsequent removal of phenol from waste water. The effects of initial phenol concentration, pH and adsorbent particle size on the simultaneous adsorption-biodegradation (SAB) of phenol were studied. The batch simultaneous adsorption and biodegradation (SAB) of phenol in simulated phenol waste water by pineapple peels immobilized Pseudomonas aeruginosa NCIB 950 has been studied with the use of glass bottles as bioreactors placed in a rotary mechanical shaker for 72 h. The results of the batch equilibrium adsorption-biodegradation studies showed that adsorption-biodegradation capacity decreased with increase in particle size. The equilibrium adsorption-biodegradation data were analyzed by the Langmuir, Freundlich and Redlich-Peterson models of adsorption. The results showed that the equilibrium data for phenol degradation sorbent systems were well fitted to the three adsorption models with Langmuir and Redlich-Peterson adsorption isotherms having the best fit. The adsorption-biodegradation kinetic data obtained at different initial phenol concentrations and pH showed that the adsorption-biodegradation capacity of the pineapple peels immobilized P. aeruginosa generally increased with increase in initial phenol concentration and pH. The kinetic data were analyzed using Lagergren pseudo-first order, pseudo second-order, Elovich and intraparticle diffusion rate equations. The rate equations fitting showed that the adsorption-biodegradation kinetic data generally fitted the four rate equations tested from which the rate constants and diffusion rate constants were estimated. However, the Lagergren pseudo first-order rate equation gave the best fit and, thus the process followed first-order rate kinetics. Therefore, pineapple peels being an agricultural waste product have the potential to be used as low-cost adsorbent and support matrix for microbial culture immobilization for the removal of organic pollutant from waste water.