Study Of Identification And Security For Edible Bird’s Nest

Since the event of nitrite happened to bird’s-nest, the security of bird’s-nest has drawn muchattention. To solve this issue, we conducted a study on the determination method of nitrite andpolyphosphates in this paper, in order to establish a sensitive, rapid, accurate determination methodwith good reproducibility and low interference, which was suitable for bird’s-nest. It was a difficultyto distinguish the fake from the true for bird’s-nest. In this paper, we provided a means ofidentification by determining the content of sialic acid which was the hydrolysate of bird’s-nestglycoprotein, a characteristic component of bird’s-nest, together with the assist of high resolutionnuclear magnetic technique. The main contents and results are as follows:(1) Through the optimization of the ion chromatography (IC) parameters, composition ofmobile phases, sample extraction and purifying methods, An ion chromatography (IC) methodwas developed for the determination of polyphosphates and nitrite in bird’s nest. The results showedthat: good linear relationships were shown for polyphosphates in the range of1mg/kg~100mg/kgand r2>0.9996.The average recoveries of spiked samples were between89.5%to106.3%with therelative standard deviations (RSD) of0.9%~7.3%.The limit of detections (LODs) were0.2,0.05,0.05and0.1mg/kg for orthophosphate, pyrophosphate, tripolyphosphate and trimetaphosphate,respectively; The linear range of the method was1~50mg/kg with r2>0.9999for nitrite. Theaverage recoveries of spiked samples were between94.3%~98.6%with the relative standarddeviations (RSD) of0.59%~6.27%. The LOD was0.3mg/kg and the limit of quantitation (LOQ)was1mg/kg.(2) A rapid and sensitive method for the determination of N-acetylneuraminic acid(Neu5Ac) inEdible Bird’s Nest(EBN) by liquid chromatography tandem mass spectrometry has been developed.Samples were exacted with phosphoric acid by acid hydrolysis. The results showed that: the linearrange of the HPLC method was5~300mg/kg with r2≥0.9998. The average recoveries of spikedsamples were between92.3~105.0％with the relative standard deviations (RSD)<8%. The LODwas1mg/kg and the LOQ was5mg/kg; In the HPLC/MS/MS method, EBN was exacted withphosphoric acid by acid hydrolysis. The Neu5Ac were separated on HYPERCARB column (2.1×150mm,5μm), followed by negative electrospray ionization and multi-reaction monitoringprovided by a triple-quadrupole tandem mass spectrometer. The LOD was0.03mg/kg, and thespiked recoveries were within87.50%-97.15%, and the relative standard deviations (RSDs) were inthe range of3.98%-8.11%. The results showed that the proposed method is rapid, sensitive, precision and accurate, and can be applied to the determination of the sialic acid(N-acetylneuraminic acid) in edible bird’s nest.(3) By comparison of the NMR fingerprints of different origin edible bird’s nest andcommonly adulterated goods (pigskin, agar, and white fungus), to identify the authenticity of theedible bird’s nest.In this paper, we provided a means of identification by determining the content of sialic acidwhich was the hydrolysate of bird’s-nest glycoprotein, a characteristic component of bird’s-nest,together with the assist of high resolution nuclear magnetic technique, and an ion chromatography(IC) method was developed for the determination of polyphosphates and nitrite in bird’s nest.