盐胁迫对发芽糙米富集γ-氨基丁酸及蛋白组分变化的影响  

Effect of Salt Stress on γ-Aminobutyric Acid Accumulation and Protein Composition in Germinated Brown Rice

作　　者：陈春旭[1] 王利勤 郭元新[1] 丁志刚[1] 杨剑婷[1] 夏定胜 CHEN Chunxu;WANG Liqin;GUO Yuanxin;DING Zhigang;YANG Jianting;XIA Dingsheng(Food and Drug College, Anhui Science and Technology University, Fengyang 233100, China;Shengnong Agricultural Group Co. Ltd., Dangtu 243100, China)

机构地区：[1]安徽科技学院食品药品学院,安徽凤阳233100 [2]安徽盛农农业集团有限公司,安徽当涂243100

出　　处：《食品科学》2018年第5期87-92,共6页Food Science

基　　金：安徽省科技重大专项(15czz03103)

摘　　要：为给盐胁迫处理发芽糙米的营养价值评价和产品开发提供科学依据,以南粳46稻米为原料,探讨在盐胁迫处理下发芽糙米中γ-氨基丁酸(γ-aminobutyric acid,GABA)含量、谷氨酸脱羧酶(glutamate decarboxylase,GAD)活力、呼吸速率等生理指标和4种蛋白质组成的变化规律。结果表明:相对正常发芽,盐胁迫使糙米芽体生长迟缓,呼吸速率增大。盐胁迫糙米发芽3 d,GABA含量和GAD活力均达到最高,分别为121.714 9 mg/100 g mf和5.784 5 U/g mf。正常及盐胁迫发芽条件下糙米清蛋白含量变化趋势一致,均为先减少后增加再减少;与正常发芽球蛋白含量逐渐降低不同,盐胁迫发芽糙米球蛋白含量先增加后减少;醇溶蛋白含量在盐胁迫条件下基本不变;糙米谷蛋白在正常及盐胁迫发芽条件下含量变化趋势一致,均为先增加再减小。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳结果表明,在发芽过程中,大分子质量的蛋白亚基降解为小分子质量的亚基,供生理活动之需。发芽至2 d主要降解清蛋白中28.6、58.7 k 的亚基和球蛋白中的24.4、40.0 kDa的亚基;发芽至3 d,谷蛋白开始积累,但主要亚基组成变化不明显。醇溶蛋白主要降解的亚基为含量较少的分子质量为15.8 kDa的亚基。In this paper,in order to provide a scientific basis for the evaluation of the nutritional value of germinated brown rice and for new product development from this plant material,γ-aminobutyric acid(GABA)content,glutamic acid decarboxylase(GAD)activity,respiration rate and four protein components in germinated brown rice from Nanjing46japonica rice were measured under salt stress.The results showed that salt stress reduced the germination rate of brown rice and increased respiration rate.GABA concentration and GAD activity reached their highest levels of121.7149mg/100g mf and5.7845U/g mf on the3rd day under salt stress.Under normal and salt stress conditions,similar trends were observed for the albumin content in germinated rice,which decreased followed by an increase.The globulin content in germinated riceunder normal conditions gradually fell,while it rose firstly and then decreased under salt stress.Under salt stress,the gliadin content remained almost unchanged.The glutenin content showed an increase followed by a decrease under both normal and salt stress conditions.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)results showed that the large subunits were degraded into smaller ones during germination,which were essential for physiological activities.On the2nd day,the28.6and58.7kDa subunits of albumin and the24.4and40.0kDa subunits of globulin were significantly degraded.Gluten began to accumulate on the3rd day,but no significant changes were observed for its major subunits.The minor subunit(15.8kDa)of gliadin was greatly degraded.

关 键 词：发芽糙米 盐胁迫 Γ-氨基丁酸 蛋白组分 

分 类 号：TS201.2[轻工技术与工程—食品科学]