Analyses of Species of Phosphorus in Four Selected Streams within Abakaliki, Metropolis, Nigeria

This work investigates the speciation of phosphorus in four selected streams within Abakaliki, Nigeria using phytase hydrolysis of phytic acid as an indicator. Phytic acid is an important organophosphorus compound that can be hydrolysed by phytases occurring in soil and water. It is the main form in which phosphorus is stored in seeds hence its availability in natural environment like water and soil. Different species of phosphorus exist in nature as a result of the interconversion, hydrolysis and oxidation occurring between organic phosphate molecules. Investigation of these species of phosphorus (PHP, FRP, TDP and DOP) is crucial to the understanding of the biogeochemical processes prevalent in any aquatic ecosystem. Water samples were collected from four streams (Presco campus, Ama, Udele and Iyi-okwu streams) in Abakaliki, Nigeria within a period of 5 days in October, 2012. The samples were digested with 0.04M peroxydisulphate and 0.01M H2SO4 at 121ºC for 45 minutes in an autoclave. After digestion, the presence of PHP, FRP, TDP and DOP were investigated in the water samples using a spectrophotometer at wavelength of 820 nm. Results obtained showed varying concentrations of PHP, FRP, TDP and DOP ranging from ±0.0093-0.069 mgL-1P, 0.205-0.233 mgL-1P, 0.297-0.520 mgL-1P and 0.081-0.127 mgL-1P respectively. Recovery studies using Adenosine-triphosphate (ATP) and the calcium salt of phytic acid (PTA) as model organic phosphorus compounds gave quantitative recoveries ranging from 92-96%. One-way ANOVA showed that sampling location significantly influenced the mean concentration of TDP, FRP and DOP in the affected streams. This technique was effective in digesting both the model compounds and the real water samples. Also, the soluble phytase was effective in hydrolyzing phytic acid and phytase hydrolysable phosphorus (PHP) present in the water samples.

This work investigates the speciation of phosphorus in four selected streams within Abakaliki, Nigeria using phytase hydrolysis of phytic acid as an indicator. Phytic acid is an important organophosphorus compound that can be hydrolysed by phytases occurring in soil and water. It is the main form in which phosphorus is stored in seeds hence its availability in natural environment like water and soil. Different species of phosphorus exist in nature as a result of the interconversion, hydrolysis and oxidation occurring between organic phosphate molecules. Investigation of these species of phosphorus (PHP, FRP, TDP and DOP) is crucial to the understanding of the biogeochemical processes prevalent in any aquatic ecosystem. Water samples were collected from four streams (Presco campus, Ama, Udele and Iyi-okwu streams) in Abakaliki, Nigeria within a period of 5 days in October, 2012. The samples were digested with 0.04M peroxydisulphate and 0.01M H2SO4 at 121ºC for 45 minutes in an autoclave. After digestion, the presence of PHP, FRP, TDP and DOP were investigated in the water samples using a spectrophotometer at wavelength of 820 nm. Results obtained showed varying concentrations of PHP, FRP, TDP and DOP ranging from ±0.0093-0.069 mgL-1P, 0.205-0.233 mgL-1P, 0.297-0.520 mgL-1P and 0.081-0.127 mgL-1P respectively. Recovery studies using Adenosine-triphosphate (ATP) and the calcium salt of phytic acid (PTA) as model organic phosphorus compounds gave quantitative recoveries ranging from 92-96%. One-way ANOVA showed that sampling location significantly influenced the mean concentration of TDP, FRP and DOP in the affected streams. This technique was effective in digesting both the model compounds and the real water samples. Also, the soluble phytase was effective in hydrolyzing phytic acid and phytase hydrolysable phosphorus (PHP) present in the water samples.