中国农业科学 ›› 2016, Vol. 49 ›› Issue (20): 3981-3992.doi: 10.3864/j.issn.0578-1752.2016.20.012

• 园艺 • 上一篇    下一篇

新疆杏果实发育过程中可溶性糖和有机酸的变化

郑惠文1,张秋云1,李文慧2,章世奎2,席万鹏1,3   

  1. 1西南大学园艺园林学院,重庆400716
    2新疆农科院轮台国家果树资源圃,新疆轮台 841600
    3南方山地园艺学教育部重点实验室,重庆 400715
     
  • 收稿日期:2016-04-06 出版日期:2016-10-16 发布日期:2016-10-16
  • 通讯作者: 席万鹏,E-mail:xwp1999@zju.edu.cn
  • 作者简介:郑惠文,E-mail:zhenghuiwen553@foxmail.com
  • 基金资助:
    国家自然科学基金(31471855)

Changes in Soluble Sugars and Organic Acids of Xinjiang Apricot During Fruit Development and Ripening

ZHENG Hui-wen1, ZHANG Qiu-yun1, LI Wen-hui2, ZHANG Shi-kui2, XI Wan-peng1,3   

  1. 1College of Horticulture and Landscape Architecture, Southwest University, Chongqing 400716
    2Luntai National Germplasm Garden of Fruit Trees, Xinjiang Academy of Agricultural Sciences, Luntai 841600, Xinjiang
    3Key Laboratory of Horticulture Science for Southern Mountainous Regions, Ministry of Education, Chongqing 400715
  • Received:2016-04-06 Online:2016-10-16 Published:2016-10-16

摘要: 【目的】明确新疆杏果实可溶性糖和有机酸的组成与含量特征,揭示果实发育过程中糖、酸动态变化规律。【方法】以5个新疆杏品种不同发育阶段的果皮和果肉为试验材料,使用高效液相色谱法(high performance liquid chromatograph,HPLC)检测各样品中可溶性糖和有机酸,对比分析果实发育过程中其组成与含量的变化情况。【结果】从新疆杏果实中共检测到3种可溶性糖(蔗糖、葡萄糖和果糖)。其中,蔗糖和葡萄糖为主要糖。果实成熟时,果皮中两种主要糖分别占总糖含量的60.7%—79.1%和13.5%—34.7%,果肉中占总糖含量的65.5%—82.4%和8.2%—25.9%,果皮、果肉中果糖的含量相对较低,仅占总糖含量的4.6%—10.6%和6.5%—10.7%。整个果实发育过程中,3种可溶性糖和总糖的含量均明显增加,各种糖的比例也发生明显变化。葡萄糖占总糖的比例不断减少,果皮中葡萄糖占总糖比例从79.4%降至13.5%,果肉中从74.1%降至8.2%;而蔗糖的比例不断增加,果皮中从11.0%增加到79.1%,果肉中从11.0%增加到82.4%,成为成熟果实中最主要的糖。从新疆杏果实中共检测到6种有机酸,包括苹果酸、奎宁酸、柠檬酸、酒石酸、草酸和富马酸。成熟果实中苹果酸、奎宁酸和柠檬酸是最主要的有机酸,占总酸含量的94.6%—98.3%。果实发育过程中,苹果酸和草酸呈下降趋势,柠檬酸、奎宁酸和富马酸呈上升趋势,酒石酸无明显变化规律。果实发育前期(幼果期至膨大期),总酸的含量明显增加,而在果实成熟过程中(转色期至完熟期)迅速下降。整个果实发育过程中,尽管苹果酸占主导地位,但各品种在有机酸的积累模式上有明显差异,依据其变化特点可分为2种模式:由苹果酸和奎宁酸或苹果酸向苹果酸、奎宁酸和柠檬酸3种主要有机酸共积累。果实成熟时,3种共积累酸的比例在品种间差异较大:‘库尔勒托拥’(KE)、‘阿克牙勒克’(AK)和‘克孜佳娜丽’(KZ)中,柠檬酸>苹果酸>奎宁酸;‘索格佳娜丽’(SG)中,奎宁酸>苹果酸>柠檬酸;‘苏联2号’(SL)中苹果酸、奎宁酸和柠檬酸的比例相当。果皮和果肉在可溶性糖、有机酸的组成、含量和积累模式上均无明显差异。【结论】新疆杏果实发育过程中,可溶性糖和有机酸积累呈现明显的变化规律,糖的积累模式由葡萄糖积累型向蔗糖积累型转变,有机酸由苹果酸和奎宁酸积累型或苹果酸积累型向苹果酸、奎宁酸和柠檬酸3种酸共积累的模式转变,糖、酸积累模式的转变在新疆杏果实甜度和酸度以及风味品质决定中都具有十分重要的作用。

关键词: 杏, 糖, 有机酸, 高效液相色谱, 果实发育, 果实成熟

Abstract: 【Objective】The aim of this study was to characterize the content and composition of soluble sugars and organic acids in Xinjiang apricot fruit and to reveal the change rule.【Method】In this study, the soluble sugars and organic acids in peels and pulps of five Xinjiang apricot cultivars were determined by high performance liquid chromatography (HPLC) during fruit development and ripening. 【Results】 Three sugars were identified from Xinjiang apricot fruit, including sucrose, glucose and fructose. Sucrose and glucose are the predominant soluble sugars in Xinjiang apricot fruit. At the full-ripe stage, the ratio of sucrose to total sugar was  60.7%-79.1% in peels and 65.5%-82.4% in pulps, whereas glucose occupied 13.5%-34.7% of total sugar in peels and 8.2%-25.9% in pulps, respectively. Fructose only made up 4.6%-10.6% and 6.5%-10.7% of total sugar in peels and pulps respectively. Three individual sugars identified and total sugar increased significantly throughout the whole development period. The ratio of glucose to total sugar decreased from 79.4% to 13.5% in peels and 74.1% to 8.2% in pulps, respectively. Conversely, the ratio of sucrose to total sugar increased from 11.0% to 79.1% in peels and 11.0% to 82.4% in pulps. A total of six organic acids, including malic acid, quinic acid, citric acid, tartaric acid, oxalic acid and fumaric acid, were identified from Xinjiang apricot. Malic acid, quinic acid and citric acid were the dominant organic acids in ripe fruit, occupying 94.6%-98.3% of total organic acid. During fruit development and ripening, the contents of malic acid and oxalic acid decreased dramatically, while the contents of citric acid, quinic acid and fumaric acid increased significantly, no clearly consistent trend was observed for tartaric acid. The content of total acid in fruit increased during early development (from fruitlet to enlargement stage), but decreased rapidly during fruit ripening (from turning to full-ripe stage). Though malic acid predominated in fruit throughout the whole development period, different accumulation patterns for organic acids were observed in all cultivars studied. The patterns were divided into two types: malic acid and quinic acid dominated, malic acid and citric acid dominated, or only malic acid dominated during early development period, yet all types changed to malic acid, quinic acid and citric acid dominated during ripening. However, the ratio of malic acid, quinic acid or citric acid to total organic acid differed significantly in cultivars tested during fruit ripening. The ratio order in ‘Kuerletuoyong’ (KE), ‘Akeyaleke’ (AK) and ‘Kezijianali’ (KZ) was citric acid > malic acid > quinic acid, the ratio in ‘Suogejianali’ (SG) was quinic acid > malic acid > citric acid, the ratio in ‘Sulian No. 2’ (SL) was that all three organic acids appeared to be largely equal. No significant differences were found in soluble sugars and organic acid content, composition or accumulation pattern between peels and pulps. 【Conclusion】Xinjiang apricot presented an obvious chemical changing trend of soluble sugars and organic acids accumulation during fruit development and ripening. The sugar accumulation pattern changed from glucose dominated to sucrose dominated, while the organic acids accumulation pattern changed from two or one of malic acid, quinic acid and citric acid to the accumulation of the three organic acids all together. Thus, this pattern may play an important role in sweetness, acidity and flavor determination for Xinjiang apricot fruit.

Key words: apricot, sugars, organic acids, HPLC, fruit development, fruit ripening