Potential of some autochthonous wild plants of Burundi for vegetable oil and valuable compounds production

Abstract Twelve species of indigenous plants have been studied in order to valorize some natural resources of Burundi (Eastern Africa) to investigate possibilities of vegetable oil production. Physicochemical properties and oil contents were determined from seeds harvested through five ecogeographic zones. From oilcake extracts, total sugars contents, proteins (TPrC), polyphenolic (TPhC), and flavonoids were quantified using spectrophotometry. Furthermore, antioxidant activity of oilcake extracts was assessed by 2, 2-diphenyl-b-picrylhydrazyl (DPPH) radical-scavenging and ferric reducing antioxidant power (FRAP) assays. All oil contents obtained were found to be quite similar to those of common oleaginous seeds. The two highest were found in Parinari curatellifolia (61.44 ± 4.81% Dry Matter) and Myrianthus arboreus (48.26 ± 5.96% DM). More than half of the species have shown TPrC ranging from 10 to 24% dry matter of oilcake (DM). Brachystegia longifolia was revealed exceptionally stronger antioxidant potential: effectiveness antiradical of 163.06 ± 26.29 mL/μg.min (DPPH assay) and reducing power of 2618.21 ± 161.22 GAE/100 g DM (FRAP assay). TPhC were positively correlated (p

摘要 为开发东非布隆迪的部分自然资源、探究植物油生产的可行路径，本研究对12种本土植物展开了系统性研究。从五个生态地理区域采集的种子样本中，测定了其理化特性与含油率。采用分光光度法对油饼提取物中的总糖、蛋白质（TPrC）、总多酚（TPhC）及黄酮类物质进行了定量分析。此外，通过2,2-二苯基-1-苦基肼（2,2-diphenyl-b-picrylhydrazyl, DPPH）自由基清除实验与铁还原抗氧化能力（ferric reducing antioxidant power, FRAP）实验，评估了油饼提取物的抗氧化活性。所有测得的含油率均与常见油料种子的含油率较为接近。含油率最高的两种植物为Parinari curatellifolia（61.44±4.81% 干物质占比）与Myrianthus arboreus（48.26±5.96% 干物质）。超过半数的受试物种，其油饼中的蛋白质含量介于干物质的10%至24%之间。长叶短盖豆（Brachystegia longifolia）展现出格外突出的抗氧化潜力：其DPPH实验测得的自由基清除效能为163.06±26.29 mL/μg·min，FRAP实验测得的还原能力为2618.21±161.22 GAE/100 g 干物质。总多酚含量呈正相关（p