Shemnsa Ashenafi, Adane Wondimeneh Dubale, Tessema Merid, Tesfaye Endale, Tesfaye Gizaw
Department of Chemistry, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
Department of Chemistry, Gambella University, P.O. Box 126, Gambella, Ethiopia.
J Anal Methods Chem. 2024 Jan 5;2024:8981995. doi: 10.1155/2024/8981995. eCollection 2024.
In this study, for the first time, the levels of thirteen micro- and macromineral nutrients in the leaves, seeds, and supportive soil of () were simultaneously determined using microwave plasma atomic emission spectroscopy (MP-AES). The samples were collected during the arid season, in 2019 from the three main growing areas in southern Ethiopia (Chano Mile Kebele, Nechisar Kebele, and Konso Special Woreda). A novel digestion method for leaf and seed samples was developed using an optimized acid mixture (2.5 : 0.75 : 0.5 of HNO, HClO, and HO) at 240°C for 2 hrs and 30 min, resulting in clear and colorless solutions. The method makes the digestion process more efficient by minimizing the reagent volume, reducing digestion temperature and time, and simplifying the overall procedure. The efficiency of the optimized procedure was validated by spiking experiments, and the percentage recovery ranged between 94 and 110%. Under optimized experimental conditions, higher concentrations of essential minerals (K, Na, Ca, and Mg) were observed in the plant leaf and seed samples from the three areas. In addition, significant amounts of trace elements (Fe, Mn, Zn, and Cu) were also found. Importantly, no traces of the toxic elements (Cd and Pb) were detected in any of the analyzed samples, suggesting that the leaves and seeds of are valuable sources of both micro- and macromineral nutrients and are safe from toxic metals. From a dietary perspective, the seed contains almost comparable concentrations of minerals as the leaves. As a result, the seeds of can serve as an alternative source of minerals and play a role in overcoming the current global food crisis, particularly in the dry season. Analysis of variance at a 95% confidence level revealed significant differences in the levels of all mineral nutrients between the three sample means except K, Ca, Co, and Cu. Generally, the developed method includes an innovative digestion procedure that minimizes reagent consumption, operates at lower temperatures, and requires shorter digestion times, thereby optimizing resource utilization and maintaining analytical accuracy. Notably, the absence of toxic elements in the MP-AES procedure highlights the safety and reliability of leaves and seeds as valuable, contamination-free sources of essential nutrients.
在本研究中,首次使用微波等离子体原子发射光谱法(MP-AES)同时测定了()叶片、种子及支撑土壤中13种微量和常量矿物质营养素的含量。样本于2019年干旱季节从埃塞俄比亚南部三个主要种植区(查诺·米莱村、内奇萨尔村和孔索特别行政区)采集。开发了一种针对叶片和种子样本的新型消解方法,使用优化的酸混合物(硝酸、高氯酸和过氧化氢的比例为2.5∶0.75∶0.5),在240°C下消解2小时30分钟,得到澄清无色的溶液。该方法通过减少试剂用量、降低消解温度和时间以及简化整个流程,使消解过程更高效。通过加标实验验证了优化程序的效率,回收率在94%至110%之间。在优化的实验条件下,在来自这三个地区的植物叶片和种子样本中观察到较高浓度的必需矿物质(钾、钠、钙和镁)。此外,还发现了大量的微量元素(铁、锰、锌和铜)。重要的是,在任何分析样本中均未检测到有毒元素(镉和铅)的痕迹,这表明()的叶片和种子是微量和常量矿物质营养素的宝贵来源,且无有毒金属污染。从饮食角度来看,种子所含矿物质浓度与叶片几乎相当。因此,()的种子可作为矿物质的替代来源,在克服当前全球粮食危机方面发挥作用,尤其是在旱季。在95%置信水平下的方差分析显示,除钾、钙、钴和铜外,三个样本均值之间所有矿物质营养素水平存在显著差异。总体而言,所开发的方法包括一种创新的消解程序,可最大限度地减少试剂消耗,在较低温度下操作,且消解时间较短,从而优化资源利用并保持分析准确性。值得注意的是,MP-AES程序中未检测到有毒元素,突出了()叶片和种子作为必需营养素的宝贵、无污染来源的安全性和可靠性。