Separation And Purification Of Bitter Almonds Proteins And Characterization As Drug Carriers

As one of the most common drugs in Chinese herbal compound and Traditional Chinese medicine unilaterally, bitter almond’s medicinal value is recorded in many ancient books. Bitter almond has the effect of relieving cough, asthma and relaxing bowel. In recent years, the study in bitter almond oil and amygdalin become the focus, but few on the bitter almond protein that also has an important role research, the study of bitter almond protein separation has rarely documented. Studies have shown that bitter almond protein is composed of subunits, this finding bring the new research direction for exploring the nature of bitter almond protein, while this finding let the bitter almond protein to become drug carriers have a natural advantage.The topic is based on the separation and purification of protein, and analyzing the biological properties of the protein subunits isolated. In the study, protein subunits as the object, studying the relationship between the subunit recombinant and protein nanoparticles formed, discussion the possibilities and advantages of bitter almond proteins as drug carriers.By separating and purifying, experiment obtain three protein subunits and named APa, APb, APc respectively, molecular weight determined by mass spectrometry are 37619.7 Da,33315.3 Da,20615.7 Da respectively; isoelectric point determined by isoelectric focusing are 5.44,5.33,6.54 respectively; obtaining subunit amino acid composition and N-terminal sequence, providing basic data for the future to determine the biological activity of subunit.Under natural pH, the protein concentration of APa, APb, APc are 0.213 mg/mL,0.127 mg/mL,0.279 mg/mL, by using the laser particle analyzer and electrophoresis, studying the recombination of subunits and mixed subunit on the heating process. The experiment results show that subunits does not aggregation in the heating process, on the contrary, APa or APb mixed with APc system gathered occur in the process of heating, particle size are more than 2000 nm, and when the three subunits mixed at the same time, the subunits mixed system form 60-100 nm nano particles, when heated to 35℃, the Zeta potential achieve the most stable value-28.7 mV, the particle radius is 70 nm.Through the use of different system to deal with various hybrid subunits systems for examining the aggregation mechanism, experimental results show that APa or APb mixed with APc system in the aggregation process relies mainly on the hydrophobic effect make the protein aggregation, with less involved in covalent bond; three subunits hybrid mixed system in the process of gathering relies on the interaction of hydrophobic effects and covalent bond.By using the laser paticle analyzer, examining the particle formed by bitter almond protein concentrate and three subunits hybrid system in structure and aggregation mechanism, results showed that the particle size formed by bitter almond protein concentrate is 500 nm, and the nanoparticle size produced by subunits hybrid system is 70 nm. By using of different processing system to deal with various hybrid systems, Results showed that the bitter almond protein concentrate particles gathered in disulfide bond, lack of hydrophobic effect of participation, and poor stability, and subunit hybrid system due to the effect of hydrophobic and covalent bond interaction, make the nanoparticle size smaller and more stable.