Department of Chemistry, College of Science, Bahir Dar University, Bahir Dar, Ethiopia.
Department of Chemistry, College of Natural Science, Debre Tabor University, Debre Tabor, Ethiopia.
PLoS One. 2022 Aug 2;17(8):e0272010. doi: 10.1371/journal.pone.0272010. eCollection 2022.
Teff [Eragrostis tef (Zuccagni) Trotter] is a small-sized cereal grain and an indigenous crop in Ethiopia. The Amhara region is one of the major teff producers regions in the country. However, information on the phenolic content of the region's teff varieties is limited. Seventy-two teff samples were collected from three administrative zones (West Gojjam zone, Awi zone, and East Gojjam zone) of the Amhara region of Ethiopia. The samples' total polyphenol and flavonoid contents were determined using colorimetric methods. The total flavonoid contents expressed as catechin equivalent, CE (i.e., under alkaline conditions) and quercetin equivalent, Q.E (i.e., under the methanolic solution of AlCl3) were found to be in the range of 7.66 ± 0.60-57.36 ± 3.87 mg C.E and 15.45 ± 0.15-113.12 ± 3.09 mg Q.E per 100 g of teff samples, respectively. The corresponding total polyphenol content (TPC), described as gallic acid equivalent (G.A.E.), was in the range of 46.21 ± 1.20-133.32 ± 5.44 mg G.A.E. The results showed that the mean TPC value of the teff samples from the West Gojjam zone was enriched with polyphenol than samples from the Awi zone and East Gojjam. Furthermore, it was noted that the mean TPC and TFC values did not vary significantly between samples of the East Gojjam and Awi zone (p > 0.05). In contrast, a significant difference in mean TPC and TFC-Q.E were noted between the sampling zone of East Gojjam and West Gojjam and between West Gojjam and Awi zones (p < 0.05). These significant variations in TPC and TFC might be due to observable variations in the agroecological zones and the genetic-make-up of the samples. Person correlation indicated a significant positive correlation matrix between the three variables (p = 0.01). The teff samples were trying to be classified based on their geographical origin using hierarchical cluster analysis (HCA) and biplots. Accordingly, the variance explained by component 1 (PC1) is 67.2%, and the variance explained by component 2 (PC2) is 20.0%.
埃塞俄比亚的苔麸（Eragrostis tef （Zuccagni）Trotter）是一种小型谷物，也是当地的一种作物。该国的阿姆哈拉地区是苔麸的主要生产地区之一。然而，关于该地区苔麸品种的酚类含量的信息有限。本研究从埃塞俄比亚阿姆哈拉地区的三个行政区（西戈贾姆区、阿维区和东戈贾姆区）收集了 72 个苔麸样本。使用比色法测定了样品的总多酚和类黄酮含量。以表儿茶素当量（CE，即在碱性条件下）和槲皮素当量（Q.E，即在甲醇溶液中的 AlCl3 条件下）表示的总类黄酮含量范围分别为 7.66 ± 0.60-57.36 ± 3.87 mg CE 和 15.45 ± 0.15-113.12 ± 3.09 mg Q.E/100 g 苔麸样品。相应的总多酚含量（TPC），以没食子酸当量（G.A.E.）表示，范围为 46.21 ± 1.20-133.32 ± 5.44 mg G.A.E。结果表明，西戈贾姆区苔麸样品的平均 TPC 值比阿维区和东戈贾姆区的样品富含多酚。此外，还注意到东戈贾姆区和阿维区的样品之间的平均 TPC 和 TFC 值没有显著差异（p > 0.05）。相比之下，东戈贾姆区和西戈贾姆区以及西戈贾姆区和阿维区之间的 TPC 和 TFC-Q.E 的平均值有显著差异（p < 0.05）。TPC 和 TFC 的这些显著变化可能是由于观察到的农业生态区和样品的遗传组成的变化。Person 相关性表明三个变量之间存在显著的正相关矩阵（p = 0.01）。使用层次聚类分析（HCA）和双变量图尝试根据地理来源对苔麸样品进行分类。因此，第一成分（PC1）解释的方差为 67.2%，第二成分（PC2）解释的方差为 20.0%。
