Laboratory for the Improvement of Plants and Valorization of Agroressources, National School of Engineering of Sfax (ENIS), University of Sfax, Sfax 3038, Tunisia; Université de Tunis El Manar, Faculté des Sciences de Tunis, Campus Universitaire, 2092 Tunis, Tunisia.
LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal.
Food Chem. 2022 Mar 30;373(Pt A):131416. doi: 10.1016/j.foodchem.2021.131416. Epub 2021 Oct 20.
This work studies the extraction and purification of a novel arabinogalactan from pistachio external hull. It was extracted with a simple method from pistachio hull which is considered as unexploited waste. Based on the results of sugar analysis by GC-FID, glycosidic linkage by GC-MS, NMR spectroscopy, and molecular weight by Size Exclusion Chromatography, pistachio hull water soluble polysaccharides (PHWSP) were identified as a type II arabinogalactan (AG), with characteristic terminally linked α-Araf, (α1 → 5)-Araf, (α1 → 3,5)-Araf, terminally linked β-Galp, (β1 → 6)-Galp, and (β1 → 3,6)-Galp. DEPT-135, HSQC, HMBC and COSY NMR data suggested the presence of (β1 → 3)-Galp mainly branched at O-6 with (β1 → 6)-Galp chains, α-Araf chains, and terminally linked α-Araf. These AG from pistachio external hulls showed in vitro stimulatory activity for B cells, suggesting their possible use as an immunological stimulant in nutraceutical and biomedical applications.
本研究从被认为未开发的废物——开心果外壳中，用简单的方法提取并纯化一种新型阿拉伯半乳聚糖。通过 GC-FID 进行糖分析、GC-MS 进行糖苷键分析、NMR 光谱分析和尺寸排阻色谱法进行分子量分析，确定开心果壳水溶性多糖（PHWSP）为 II 型阿拉伯半乳聚糖（AG），具有特征性末端连接的α-Araf、（α1→5）-Araf、（α1→3,5）-Araf、末端连接的β-Galp、（β1→6）-Galp 和（β1→3,6）-Galp。DEPT-135、HSQC、HMBC 和 COSY NMR 数据表明，（β1→3）-Galp 主要以（β1→6）-Galp 链、α-Araf 链和末端连接的α-Araf 支链存在于 O-6 位。这些来自开心果外壳的 AG 体外刺激 B 细胞活性，提示它们可能作为免疫刺激剂用于营养保健品和生物医学应用。
