中国农业科学 ›› 2021, Vol. 54 ›› Issue (6): 1229-1242.doi: 10.3864/j.issn.0578-1752.2021.06.013

• 园艺 • 上一篇    下一篇

蜜柚果实不同空间部位植酸及矿质营养有效性的分布特征

宋彪1,2,3(),徐凯悦2,3,王晓华2,3,郭九信2,3,吴良泉2,3,苏达1,3()   

  1. 1福建农林大学农学院/作物遗传育种与综合利用教育部重点实验室,福州 350002
    2福建农林大学资源与环境学院,福州 350002
    3福建农林大学国际镁营养研究所,福州 350002
  • 收稿日期:2020-06-17 接受日期:2020-09-24 出版日期:2021-03-16 发布日期:2021-03-25
  • 通讯作者: 苏达
  • 作者简介:宋彪,E-mail:761546511@qq.com
  • 基金资助:
    国家重点研发计划(2016YFD0200400);国际镁营养研究所开放基金(IMI2018-12)

Spatial Distribution of Phytic Acid and Minerals’ Availability in Pomelo Fruit

Biao SONG1,2,3(),KaiYue XU2,3,XiaoHua WANG2,3,JiuXin GUO2,3,LiangQuan WU2,3,Da SU1,3()   

  1. 1Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops/College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou 350002
    2College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002
    3International Magnesium Institute, Fujian Agriculture and Forestry University, Fuzhou 350002
  • Received:2020-06-17 Accepted:2020-09-24 Online:2021-03-16 Published:2021-03-25
  • Contact: Da SU

摘要:

【目的】明确植酸(PA)、矿质元素含量及其有效性在蜜柚果实中的空间分布特征,为蜜柚矿质营养的生物强化以及果实综合营养评价提供理论参考。【方法】以平和蜜柚产区5个代表性蜜柚品种(白肉蜜柚、黄金蜜柚、红肉蜜柚、三红蜜柚、红棉蜜柚)为供试材料,将成熟期蜜柚果实从外到内细分为黄皮层、白皮层、囊衣和果肉,分别利用铁沉淀法、ICP-MS(Inductively coupled plasma mass spectrometry)、PA与矿质元素的摩尔比,分析蜜柚果实不同空间区位的PA、矿质营养的含量及其有效性;并在此基础上利用三元模型模拟锌在人体肠道内的有效吸收。【结果】蜜柚果实中,磷组分(磷、无机磷)以果肉中含量最高,但PA含量最低。PA含量从外到内总体表现为持续降低的趋势(黄皮层>白皮层>囊衣>果肉)。果肉中植酸磷(PAP)含量仅占总磷的4%,而果皮为30%。此外,果肉中PA表现出显著的基因型差异。不同蜜柚品种果肉中PA含量以红肉蜜柚最高,三红蜜柚和白肉蜜柚最低,最大相差2.6倍。而果肉中磷和无机磷在不同蜜柚品种之间差异不显著。从矿质元素的分布角度看,果皮(黄皮层、白皮层和囊衣)中钙(Ca)的含量较高,果肉中磷的含量较高,而铁(Fe)在果皮不同部位均显著高于果肉,且以在黄皮层和果肉中变异最大。受蜜柚果实不同部位PA和矿质元素含量的共同影响,黄皮层中的[PA]/[Mg]和[PA]/[Fe]最高,白皮层中[PA]/[Zn]和[PA]/[Mn]最高,而果肉中[PA]/[Ca]最高。此外,果肉中矿质元素的有效性也表现出显著的基因型差异。黄金蜜柚的[PA]/[Fe]是红棉蜜柚的将近6倍。红棉蜜柚的[PA]/[Zn]是白肉蜜柚和三红蜜柚的3.6倍。5个供试蜜柚品种中,三红蜜柚和白肉蜜柚属低PA、高矿质元素有效性品种。【结论】蜜柚果实的PA、矿质元素及其有效性在不同蜜柚品种之间,以及果实不同空间部位均存在显著差异。果肉中磷主要以无机磷的形态存在,而非PA。推测果肉的低PA背景对矿质元素的抑制效应相对有限。而果皮中(黄皮层、白皮层)PA含量相对较高,在果皮深加工过程中需注意其矿质元素的有效发挥。

关键词: 蜜柚, 植酸, 果实营养, 矿质元素有效性, 品质

Abstract:

【Objective】This study was aimed to elucidate the spatial distribution of phytic acid (PA), mineral concentration and their availabilities in pomelo fruits, and these findings could provide theoretical bases for biofortification of mineral nutrition and comprehensive nutritional evaluation of pomelo fruit. 【Method】Five representative pomelo cultivars (white-fleshed pomelo, golden-pomelo, red-fleshed pomelo, three-red pomelo, and red-albedo pomelo) grown in Pinghe County, Fujian Province, were used in the present study. At the ripening stage, the representative fruits from each cultivar were selected and divided the whole fruit into four spatial parts, i.e. flavedo, albedo, segment membrane and juice sac. The PA, mineral concentration and their availabilities were analyzed by iron precipitation spectrometry, inductively coupled plasma mass spectrometry (ICP-MS) and molar ratio of phytic acid to minerals in different spatial locations of pomelo fruit. In addition, Zn bioavailability was also evaluated by the ternary model, a mathematical model of zinc absorption in human intestine. 【Result】The concentration of phosphorus (total phosphorus) and inorganic phosphorus was highest in juice sac, but the concentration of PA was the lowest in juice sac. The PA concentration decreased persistently from the outer (flavedo) to the inner (pulp), i.e. flavedo > albedo > segment membrane > juice sac. The concentration of phytate-phosphorus in juice sac was only 4% of total phosphorus, while that in peel was 30%. In addition, the significant cultivar differences of PA were recorded in juice sac. The concentration of PA in juice sac of different pomelo cultivars was the highest in red-fleshed pomelo, while which was the lowest in three-red pomelo and white-fleshed pomelo, with 2.6-fold difference. However, non-significant difference was found in phosphorus and inorganic phosphorus among different pomelo cultivars. From the perspective of mineral distribution in pomelo, the higher concentration of calcium (Ca) was recorded in peel (flavedo, albedo, and segment membrane), while the higher concentration of phosphorus was found in juice sac. Iron (Fe) in peel was significantly higher than that in juice sac, and the variation was the largest in flavedo and juice sac. Influenced by both PA and minerals in different spatial location of pomelo fruit, [PA]/[Mg] and [PA]/[Fe] was the highest in flavedo, [PA]/[Zn] and [PA]/[Mn] was the highest in albedo, whereas [PA]/[Ca] was the highest in the juice sac. There were also significant cultivar differences in the mineral availability in juice sac. The [PA]/[Fe] of golden-pomelo was nearly six times higher than that of red-albedo pomelo. The [PA]/[Zn] of red-albedo pomelo was 3.6 times higher than that of white-fleshed pomelo and three-red pomelo. Generally, among the five pomelo cultivars, three-red pomelo and white-fleshed pomelo had the relatively low PA while high mineral availabilities. 【Conclusion】Significant cultivar and spatial positional differences existed in PA, minerals and their availabilities in pomelo fruits. Phosphorus in the pomelo juice sac mainly existed in the form of inorganic phosphorus, rather than PA. The results suggested that the inhibitory effect of PA on mineral availability was relatively small and limited in the juice sac. However, the concentration of PA in peel (flavedo, albedo) was relatively higher. Therefore, it is necessary to pay attention to the minerals availabilities during pomelo peel related deep food processing.

Key words: pomelo, phytic acid, fruit nutrition, mineral availability, quality