橡子淀粉基本理化特性及其抗氧化作用分析

Analysis on Basic Physicochemical Properties and Antioxidant Activities of the Starch from Acorn

摘要: 本文探讨橡子淀粉基本理化特性及其体外抗氧化效果。分析橡子淀粉润胀能力、水解能力、直链淀粉和支链淀粉含量、特征官能团、热力学特性、晶型结构、微观形貌、单宁组成、还原能力及清除超氧阴离子O₂^-、羟自由基(∙OH)、1,1-二苯基-2-三硝基自由基(DPPH∙)的能力。结果表明：橡子淀粉润胀能力为(68.00 ± 13.35) g/g，葡萄糖转化率为(0.23 ± 0.025) g/g，直链淀粉和支链淀粉质量分数分别为19%和81%；橡子淀粉红外光谱峰型特征与马铃薯淀粉、糯米淀粉相似，相变起始温度在101.19℃，高峰温度在103.32℃，晶型结构为A型，微观形貌呈球形，其淀粉中单宁含量为(1.60 ± 0.11) g/100g，主要为鞣花酸(1.54 g/100g)和少量槲皮素(0.064 g/100g)，对铁氰化钾的还原能力、清除O₂^-、∙OH和DPPH∙的效果良好。橡子淀粉具有一般淀粉的基本特性，其单宁主要组分为鞣花酸，具有较好的抗氧化作用。

Abstract: This paper explored physicochemical properties of acorn starch, and its antioxidant activity in vitro. The swelling capacity, the hydrolysis capacity, content of amylose and amylopectin, characteristic functional groups, thermodynamic properties, crystal structure, micromorphology and tannins compositions of acorn starch were analyzed. Its reducing power and its scavenging activity on superoxide anion O₂^-, hydroxy radicals (∙OH), and 1,1-diphenyl-2-picrylhydrazyl radical (DPPH∙) were evaluated. The results showed that the swelling capacity of acorn starch was (68.00 ± 13.35) g/g, and the glucose conversion rate was (0.23 ± 0.025) g/g. The mass percent of amylose and amylopectin were 19% and 81%, respectively. Characteristic functional groups of the infrared spectra of acorn starch were similar to those of potato and glutinous rice starch. Onset temperature of phase transition was at 101.19˚C, and the peak temperature was at 103.32˚C. Acorn starch crystal structure exhibited A-type. Microscopic morphology showed spherical. The content of tannins in starch was (1.60 ± 0.11) g/100g, and the main components were ellagic acid (1.54 g/100g) and a small amount of quercetin (0.064 g/100g). The acorn starch reducing power on ferricyanide, and its scavenging effects on O₂^- , ∙OH, and DPPH∙ were significant. Acorn starch is one kind of the general starch, and its tannins is mainly made up of ellagic acid and its antioxidant activitives are good.