反相高效液相色谱法测定西番莲中的有机酸

本研究旨在表征西番莲果皮多糖锌（WPEP-Zn）的结构并确定其益生元作用。采用傅里叶变换红外色谱、X射线衍射、扫描电镜、刚果红实验和热重分析对WPEP-Zn进行结构表征。将WPEP-Zn作碳源，研究其对植物乳杆菌（Lactobacillus plantarum）、德氏乳杆菌保加利亚亚种（Lactobacillus delbrueckii（subsp.）bulgaricus）、短乳杆菌（Lactobacillus brevis）和嗜热链球菌（Streptococcus thermophilus）的益生元作用。结果表明，WPEP-Zn的总糖含量和糖醛酸含量分别为23.26%和50.46%，锌含量为10.64 mg/g。与西番莲果皮多糖（WPEP）相比，WPEP-Zn仍具有三螺旋结构，且结晶度降低、红外吸收峰发生变化、形貌结构改变、热稳定性增强。WPEP-Zn促进上述4种益生菌生长的最佳质量浓度分别为3%、2%、2%、2%，对植物乳杆菌、德氏乳杆菌保加利亚亚种和短乳杆菌的益生元效果低于WPEP，对嗜热链球菌的益生元效果高于WPEP，结果表明WPEP-Zn具有益生元作用。WPEP-Zn的研究为新型多糖补锌剂的开发以及西番莲资源的高效利用提供了依据。

Dietary fibre and antioxidant compounds in passion fruit (Passiflora edulis f. flavicarpa) peel and depectinised peel waste

This study aimed to characterize the structure of Passiflora edulis Sims peel polysaccharide-zinc (WPEP-Zn) and its prebiotic effects. The structural characteristics of WPEP-Zn were determined using Fourier transform infrared spectrometer, X-ray diffractometer, scanning electron microscope, Congo red test, and thermogravimetric analyzer. The WPEP-Zn was used as carbon source to study its prebiotic effects on Lactobacillus plantarum, Lactobacillus delbrueckii (subsp.) bulgaricus, Lactobacillus brevis, and Streptococcus thermophilus. The results showed that WPEP-Zn had sugar and uronic acid content of 23.26% and 50.46%, respectively, whereas the zinc content was 10.64 mg/g. It had a triple helix structure compared with the Passiflora edulis Sims peel polysaccharide (WPEP). Its relative crystallinity decreased, the infrared absorption peak changed, the morphological structure altered, and the thermal stability enhanced. The optimal concentrations of WPEP-Zn used to promote the growth of the four bacteria strains were 3%, 2%, 2%, and 2%, respectively. The prebiotic effects of WPEP-Zn on L. plantarum, L. delbrueckii (subsp.) bulgaricus, and L. brevis were lower than WPEP, but its prebiotic effect on S. thermophilus was higher than the WPEP. The findings revealed the prebiotic effect of WPEP-Zn. The study on WPEP-Zn provided a basis for developing new polysaccharide-zinc supplements and the effective utilization of passion fruit resources.