Study On The Elimination Of Sodium Dehydroacetate Residue In Foods Derived From Animals

Sodium Dehydroacetate (DHA-S) has been widely used as preservative and antimicrobial agent in food products, livestock feed products and cosmetic products. Currently, few reports were focused on the elimination of sodium dehydroacetate residue in animal tissues used as feed additive. A high performance liquid chromatography (HPLC) method for determination of DHA-S residues was developed for chicken and swine’s tissues. The study on the elimination regularity of DHA-S residue in animal tissues provides scientific basis for the residue monitor of DHA-S and establishment of its withdrawal time.The HPLC method for the determination of DHA-S in muscle, liver, kidney and skin-fat tissues was developed. The DHA-S was extracted with acetonitrile, defatted with n-hexane and purified with C18cartridge extraction column. The liquid chromatography (LC) was performed on a X Bridge C18column (5μm,4.6mm×250mm) with a mobile phase of0.02mol/L acetate buffer (pH4.0)-methanol (31/69, v/v) and ultraviolet absorption detection at293nm. Results showed the calibration curves plotted from0.2～10mg/L were good linear with a correlation coefficient of0.9996. The mean recoveries of DHA-S spiked in muscle at three concentrations of0.2mg/kg,0.4mg/kg and2.0mg/kg were between85.96%～91.33%, in liver80.18%～84.63%, in kidney80.93%～84.64%and in skin-fat79.84%-83.49%. The coefficient of variation (CV) within-day and between-day in spiked samples were lower than6.5%. The limit of detection (LOD) and the limit of quantification (LOQ) were0.08mg/kg and0.2mg/kg respectively. The established method can be applied to residue analysis of DHA-S in various animal tissues.The elimination of DHA-S residue in chicken tissues was investigated in which56Yellow Broiler Chicks were administered at the dosage of200mg/kg for30days successively. Six broilers were slaughtered each time at1,3,6,9,12,15,18,21days after the last administration. Results showed the residue level of DHA-S in chicken tissues were kidney> liver> muscle> skin-fat. The concentration residue of DHA-S in kidney was0.6817mg/kg,0.5929mg/kg in liver,0.3426mg/kg in muscle and0.1978mg/kg in skin-fat at1st day withdrawal time. If the LOQ0.2mg/kg was set as provisional MRLs of DHA-S in animal tissues, the withdrawal time simulated by the WT1.4program for withdrawal time calculation was the longest in chicken’ kidney (12.37d) and then the withdrawal time of DHA-S in broiler was recommended13d.The elimination of DHA-S residue in swine tissues was studied.33healthy swine were administered at the dose of200mg/kg for a month successively. Three swine were slaughtered at1,3,6,9,11,13,15,17,19,21days after the last administration respectively. The residues level of DHA-S in kidney was the most high, degressive order was in liver, in muscle and in skin-fat. The residue concentration of DHA-S in kidney was1.1220mg/kg at1st day withdrawal time,1.0576mg/kg in liver,0.5892mg/kg in muscle,0.2093mg/kg in skin-fat. If0.2mg/kg was assumed as the MRLs of DHA-S in animal tissues, the withdrawal time simulated by the WT1.4program for withdrawal time calculation was the longest in swine’kidney to18.60d. Then the withdrawal time of DHA-S in swine tissues was recommended19d.