The Spectroscopic Characteristics Of The Baltic Amber And The Study Of The Interaction Between Its Extract And Bovine Serum Albumin

As the demand for amber increases in the market,amber prices are getting higher and higher,so there are often other substances posing as amber,such as coba resins,synthetic resins,modern resins,plastics and so on.In addition,there will be some optimized amber and remanufactured amber,which has caused serious losses to consumers.Therefore,the identification of amber is an important research.Amber has its unique medicinal value,but there are few pharmacological studies on amber at present.In this paper,we mainly studied three aspects:the basic properties and structure of Baltic amber,infrared spectrum characteristics and theinteraction between its extract and bovine serum albumin.The first part mainly introduces the basic properties of amber.By SEM,we know that that transparent amber has a smaller surface pore and a denser structure;opaque amber?beeswax?has a large surface porosity and a loose structure.It can be known that the Baltic amber has a regular structure and a high degree of petrifaction by TEM.Upon excitation at365 nm with a UV lamp,the Baltic amber exhibits yellow,yellow-green and blue-green fluorescence,while the oxide film of amber has almost no fluorescence.In the second part,the Baltic amber,Burmese amber,Indonesian coba,and Russian coba were determined by Fourier transform infrared spectroscopy,and the typical characteristics of Baltic amber were identified by infrared spectroscopy.The results are as follows:1.The basic skeletons of all four samples were aliphatic structures.2.In the wavenumber range of1300cm^-11100cm^-1,Baltic amber exhibited its unique characteristic absorption shoulder.3.3078cm^-1=C-H stretching vibration peak,1643 cm^-1 C=C carbon-carbon double bond stretching vibration peak,887 cm^-1=C-H bending vibration peak indicates that there may be terminal olefins in Baltic amber.And the three peaks usually exist at the same time.4.In the1050 cm^-1 to 950 cm^-1 region,Baltic amber has a broad absorption peak or overlapping double peaks,which is the common embodiment of the hydroxyl expansion vibration(1020 cm^-1)and the C-H bending vibration(980cm^-1)of the unsaturated alkene in its structure.Thirdly,we demonstrated that the Baltic amber extract could interact with BSA by quenched fluorescence spectroscopy and Rayleigh scattering fluorescence spectroscopy?RLS?.The quenching constant decreases with increasing temperature,which is proved to be static quenching.The number of binding sites is calculated to be 1.The results of synchronous fluorescence spectroscopy and three-dimensional fluorescence spectroscopy revealed that the addition of Baltic amber powder extract made the change of the polypeptide skeleton of the BSA.It mainly reduced the polarity of the external microenvironment of tryptophan and enhanced the hydrophobicity.However,the effect on tyrosine is small,which indicates that the binding site of amber powder extract and BSA is closer to tryptophan.