Effects Of Almond Extract Protein And Peptide Flat Cell Activity

Almond contains considerable protein, more than26%, mainly composing of digestible protein. There are eight kinds of essential amino acids in almond protein, accounting for about35%of the total amino acids, which can balance insufficient diet. So, almond protein is kind of consumption of high-value vegetable protein. With the rise of the pursuit of natural foods, almonds research and product development have gradually become a new bright spot in the research field of functional foods. The present study of almond protein mainly concentrated in the traditional alkali extraction and acid precipitation method, and focus on antihypertensive activities in vitro and in vivo after protease hydrolysis to obtain almond peptide. It have not been studied on the cell level to the almond peptide activity. In this paper, a new type of non-toxic green solvents polyethylene glycol combination of microwave-assisted was used to extract the almond protein, the protein was hydrolyzed in order with Protamex and Alcalase, and then the effect of almond peptide on human umbilical vein endothelial cells (HUEVC) was investigated and biological activity of almond peptide was explored in the cellular level. This study provides a theoretical basis for further research of hypotensive mechanism of almond peptide in molecular level and development of the hypotensive health food.There are four parts in this thesis.Part one:reviewFirst, it briefly reviewed the research progress at home and abroad of almond protein; Then, it introduced plant protein extraction, precipitation separation and surfactant extraction of natural products of the status quo; Fllowlly it summarized the preparation of ACE inhibitory peptides by enzymatic method;Finally, it discussed the relationship between vascular endothelial cell and hypertension.Part two:study on the extraction technology of almond protein First, it used sodium hydroxide, sodium chloride, and the surfactants of the different molecular weight polyethylene glycol as extracting solvent, compared the influence of different solvents on the almond protein extraction efficiency. As a result, polyethylene glycol200(PEG200) was the highest extraction efficiency. Therefore, it choosed polyethylene glycol200(PEG200) combined with microwave assisted extraction as extracting solvent of almond protein. On the base of one factor experiment, the optimized extraction condition was determined by response surface method (RSM) as following:PEG200concentration was25%, ratio of solid to liquid was1:22g/mL, microwave power was120.00W, temperature was45℃. The actual average yield of three parallel experiments was93.35%. Subsequently, almond protein were subsided by the isoelectric point-ethanol synergy precipitation method. It integrated the speed of isoelectric point precipitation with the advantages of alcohol precipitation completely. Consequently, the precipitation rate was98.81%and precipitation time was only3-5min. At last, This paper compared with polyethylene glycol (PEG) based microwave-assisted extraction, ultrasound-assisted extraction and conventional water bath extraction, polyethylene glycol (PEG) based microwave-assisted extraction were highest extraction efficiency, highest extraction purity and shortest extraction time. The rate of extraction was93.35%, extraction time was4min, the purity of the protein was95.61%.Part three:the preparation of almond peptideAlmond protein was used to hydrolyzed by Protamex and Alcalase complex enzymatic enzymatic on the basis of Protamex and Alcalase enzymatic hydrolysis. The experimental results showed that the degree of hydrolysis (DH) of Alcalase enzymatic hydrolysis was24.74%, it’s higher than the Protamex enzymatic hydrolysis. But after two kinds of enzyme hydrolysis, the degree of hydrolysis (DH) was significantly improved to32.82%. Respectively, it compared to Protamex and Alcalase single enzyme hydrolysis, the degree of hydrolysis (DH) increased65.84%,32.66%. Meanwhile, the average chain length (PCL) and the average molecular weight (Mw) of Protamex and Alcalase two kinds of enzyme hydrolysis were lower than the single enzyme hydrolysis of Protamex, and Alcalase enzymes.Part four:the effect of almond peptide on human umbilical vein endothelial cells This paper discussed cell growth, the release of nitric oxide (NO) and endothelin (ET), after human umbilical vein endothelial cells (HUVEC) were interacted with the almond wholly polypeptide and the almonds valley polypeptide. The experimental results showed that these peptides were no toxicity to human umbilical vein endothelial cells (HUVEC).The experimental groups were compared with the control group, captopril group and different dose of almond peptide group. It increased content of nitric oxide (NO) and reducing medium endothelin (ET) in endothelial culture medium. Especially, the better dose group (p<0.01) were the captopril group, the middle dose group of the almond wholly polypeptide and the almond Valley polypeptide. The results also showed that norepinephrine (NE) can promote endothelial cell growth and secretion of endothelial prime (ET) and reduce nitric oxide (NO) content. The culture medium content of nitric oxide (NO) and endothelin (ET) content were close to the control group (p>0.05) after added middle dose group of the almond wholly peptidomics and the almond Valley polypeptide. These showed that the norepinephrine group (NE group) role were against by the almond wholly polypeptide and the almond Valley polypeptide. These showed that the almond polypeptide had protective effects on vascular endothelial cells.Finally, it summarized the contents of the study.