A MAGNESIUM-LOADED HUMIC ACID AS AN ADSORBENT OF THE NUCLEIC ACID CONSTITUENTS URACIL AND URIDINE

摘要

Humic adds(HAs)give soil its color,ranging from brown to black.HAs have the ability to retain water and nutrient metals due to their high cation exchange capacity(Humic Add,2004).Compared to commercial cation exchangers,HAs not only have a higher metal-binding capacity,but they also can selectively bind and release metals(Ghabbour et al.,2001).This work focuses on a solid humic add labeled NHA extracted from a New Hampshire soil.The objective was to determine whether different temperatures and concentrations of uracil(U)or uridine(UD)affect the adsorption of these solutes by NHA that is loaded with magnesium.Solid magnesium-loaded humic acid(MgNHA)was combined with U or UD in vials containing different solute concentrations.The optical absorbance of the solutions are measured at seven temperatures ranging from 5.0 deg C to 35.0 deg C in increments of five degrees.It was found that magnesium is removed from MgNHA as the U concentration Increases,and that MgNHA catalyzes the hydrolysis of UD to U and ribose,as indicated by similar isotherms for binding of U or UD.