Preparation And Safety Evaluation Of Corn Germ Antioxidant Peptide

In order to extend the corn processing industry chain and enhance the reuse valueof corn germ meal,corn germ meal were used as raw material to prepare the corn germantioxidant peptides.The specific research content as follows:1. The results on conventional nutrition component of corn germ meal: proteinscontents of (29.88±0.37)%, fats contents of (4.96±0.13)%, crude fibers contents of(10.49+0.73)%,ashes contents of (3.28+0.10)%and water contents of (3.87+0.13)%.With the extraction yield of corn germ protein as the index,and single factorand response surface metrology experiment were used to optimize the proteinextraction process.According to laboratory condition, the experiments results wereliquid-solid radio of12:1, pH9.0, Alkali immersing time of30min, microwavepower of260W, microwave time of3min. Under the optimized condition, theprotein extraction yield was (56.92±0.12)%.2. The functional properties of the corn germ protein was studied.The resultsshowed that compared with the corn germ protein which was extracted from Alkaliliquor, the functional properties of the corn germ protein which was extracted frommicrowave assisted Alkali liquor is significantly better.3. The efficient hydrolysis technologies of corn germ protein were studied.Trypsin，Papain and Alcalase were used to hydrolyze corn germ protein, and degreeof hydrolysis (DH) and DPPH radical scavenging were used as index. Single factorand orthogonal experiment were used to optimize the hydrolyze process. The resultsof hydrolysis process of3enzymes were obtained, and it showed hat Alcalase was theefficient enzyme. And the experiment results were substrate concentration of5%, pH10.0, hydrolysis temperature of45℃, enzyme amounts of7%and hydrolysis time of180min. Under the optimized condition, the degree of hydrolysis (DH) was(20.04±0.20%) and DPPH radical scavenging was (63.76±2.09)%. 4. Hydrolysates of corn germ protein as experimental material， and thehydrolysates were separated by the ultrafilter.Different fractions of corn germantioxidant peptides were compared by antioxidant capacity in vivo (DPPH radicalscavenging) and antioxidant capacity in vitro (SOD activity, MDA content andT-AOC activity of serum). The results indicated that CGAP V (molecule weight1kDa-3kDa) had the highest antioxidant activity.5. Toxicity and safety evaluation of CGAP V were studied to provide safetyguarantee for its development and application. Acute toxicity was studied by test ofMTD, mutagenicity of CGAP was studied by sperm abnormality test, bone marrowcell micronucleus test and Ames test, and30-day feeding study were performed.Theresults show that CGAP V does not show any toxicity and mutagenicity.