Studyon Preparationand Biological Activityof Oat Peptide Ferrous Chelate

Iron has a pivotal role in a variety of important metabolic processes and iron-deficiency can cause anemia and physical damage.Therefore,extra iron supplements is indispensable during iron-deficiency.Currently,peptide iron chelate is considered as one of the best iron supplements to alleviate iron-deficiency.This paper mainly studied the optimization of preparing peptide iron chelate technology on basis of using oats as raw materials to prepare oat peptides with enzyme hydrolysis.A new type of oat peptide ferrous chelate(OP-Fe²⁺)was obtained and the structure and properties of the chelate were further studied.To understand the activity of OP-Fe²⁺in vivo,iron-deficiency anemia rat(IDA)model was established.Furthermore,the improvement effect of OP-Fe²⁺on iron-deficiency anemia in IDA rats was observed and its antioxidant capacity,liver tissue injury repair ability and mitigation effects on anxiety and depression in IDA rats were further analyzed.The results of the study are as follows:(1)Prior to extracte oat protein from oats by alkali-dissolving and acid precipitation method.After enzymatic hydrolysis,ultrafiltration was used to collect peptides fractions which molecular weight below 3 k Da and then freeze-dried to obtain oat peptides.According to single factor and response surface optimization experiments,the optimal process conditions for preparing OP-Fe²⁺were determined as follows:p H,oat peptides-Fe Cl₂ratio,oat peptides concentration,temperature and time are 5.6,4.4:1,3%,40?,30 min,respectively.At the optimal conditions,the chelating rate was up to 62.6%.(2)Used a variety of qualitative and quantitative experimental methods to study the structure and properties of OP-Fe²⁺.The sodium sulfide method qualitatively showed that oat peptides are fully chelated with ferrous ions and the chelate contained no free peptides.The results of ultraviolet scanning and infrared spectroscopy experiments demonstrated that ferrous ions are mainly combined with amino groups and carboxylic acid groups of the peptides.Fluorescence spectroscopy analysis found that there was an interaction between oat peptides and ferrous ions.The endogenous fluorescence of oat peptides was quenched and the peptides were folded in the chelation process.There was a significant difference between the oat peptides and OP-Fe²⁺which OP-Fe²⁺reduced particle size and particle height on the microscopic morphology using Scanning electron microscopy and atomic force microscopy.Anti-oxidation experiments in vitro experiments indicated that antioxidant activity of OP-Fe²⁺was significantly higher than oat peptides at the same concentration.(3)By establishing an IDA rat model,the improvement effect of OP-Fe²⁺on iron-deficiency anemia rats was studied.Compared with the model group(MG),treatment groups including low-dose,medium-dose and high-dose OP-Fe²⁺groups(OPFL,OPFM,OPFH)all have significant differences in body weight,spleen coefficient,hemoglobin value(Hb),mean erythrocyte hemoglobin concentration(MCHC),total iron binding capacity(TIBC),serum iron(SI),serum ferritin(SF)levels and glutamic-oxalacetic transaminase(AST)content(P<0.05),and they all could return to normal levels.In addition,the m RNA expression level of Hepcidin in the OPFM and OPFH groups was returned(p<0.05)to the normal level,which indicating that OPFM and OPFH groups have a better therapeutic effect than OPFL groups.Last but not least,other test results showed that OP-Fe²⁺can also enhance the body's antioxidant capacity,restore the liver damage caused by iron deficiency anemia,improve the autonomous exploration behavior of IDA rats and alleviate the anxiety and depression performance of IDA rats.