Farag Mohamed A, Rasheed Dalia M, Kamal Islam M
Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Cairo, 11562, Egypt.
Pharmacognosy Department, Faculty of Pharmacy, October 6 University, Central Axis, Part 1/1, Sixth of October, Egypt.
Food Res Int. 2015 Dec;78:327-335. doi: 10.1016/j.foodres.2015.09.024. Epub 2015 Sep 25.
Hibiscus sabdariffa (roselle) is a plant of considerable commercial importance worldwide as functional food due to its organic acids, mucilage, anthocyanins, macro and micro-nutrients content. Although Hibiscus flowers are emerging as very competitive targets for phytochemical studies, very little is known about their volatile composition and or aroma, such knowledge can be suspected to be relevant for understanding its olfactory and taste properties. To provide insight into Hibiscus flower aroma composition and for its future use in food and or pharmaceutical industry, volatile constituents from 2 cultivars grown in Egypt, viz. Aswan and Sudan-1 were profiled using solid-phase microextraction (SPME) coupled to GCMS. A total of 104 volatiles were identified with sugar and fatty acid derived volatiles amounting for the major volatile classes. To reveal for cultivar effect on volatile composition in an untargeted manner, multivariate data analysis was applied. Orthogonal projection to latent structures-discriminant analysis (OPLS-DA) revealed for 1-octen-3-ol versus furfural/acetic acid enrichment in Aswan and Sudan-1 cvs., respectively. Primary metabolites contributing to roselle taste and nutritional value viz. sugars and organic acids were profiled using GC-MS after silylation. The impact of probiotic bacteria on roselle infusion aroma profile was further assessed and revealed for the increase in furfural production with Lactobacillus plantarum inoculation and without affecting its anthocyanin content. This study provides the most complete map for volatiles, sugars and organic acids distribution in two Hibiscus flower cultivars and its fermented product.
玫瑰茄是一种在全球具有重要商业价值的植物，因其含有有机酸、黏液质、花青素、大量和微量营养素，可作为功能性食品。尽管玫瑰茄花正成为植物化学研究中极具竞争力的目标，但人们对其挥发性成分和香气知之甚少，而这些知识可能与理解其嗅觉和味觉特性相关。为深入了解玫瑰茄花的香气成分及其在食品和制药行业的未来应用，对埃及种植的两个品种（阿斯旺和苏丹 -1）的玫瑰茄花挥发性成分进行了分析，采用固相微萃取（SPME）结合气相色谱 - 质谱联用（GCMS）技术。共鉴定出104种挥发性成分，其中糖和脂肪酸衍生的挥发性成分占主要挥发性类别。为以非靶向方式揭示品种对挥发性成分的影响，应用了多变量数据分析。正交投影到潜在结构判别分析（OPLS - DA）分别揭示了阿斯旺品种中1 - 辛烯 - 3 - 醇的富集以及苏丹 -1品种中糠醛/乙酸的富集。对构成玫瑰茄味道和营养价值的主要代谢产物（即糖和有机酸）进行了硅烷化处理后，使用GC - MS进行分析。进一步评估了益生菌对玫瑰茄浸液香气特征的影响，结果表明接种植物乳杆菌会增加糠醛的产生，且不影响其花青素含量。本研究提供了两个玫瑰茄花品种及其发酵产品中挥发性成分、糖和有机酸分布的最完整图谱。
