FATTY ACIDS PROFILE, TOTAL PHENOLIC CONTENT, TOTAL FLAVONOIDS CONTENT AND ANTIOXIDANT ACTIVITY OF SESAME SEED (SESAMUM INDICUM L.) VARIETIES FROM SELECTED AREAS OF ETHIOPIA

<strong>Abstract</strong>: Sesame seed (Sesamum indicum L.) which are family herbs have potential to grow in Ethiopia. Despite this fact there are only few data in Ethiopia on the phytochemicals (phenolic content, flavonoids content, and antioxidant activities) and concentration of fatty acids. There are some data for fatty acids profile of sesame seed varieties. In this study two different varieties of sesame seeds collected from north Gondar zone (Metema woreda, West Armachiho woreda) and East Wollega zone (Amuru woreda) were investigated. Sesame seeds extracted using pure methanol (100%) and aqueous methanol (80%) with ultrasound assisted apparatus to determine total flavonoids, total phenolic and antioxidant activity by UV-vis spectroscopy and fatty acids profile was analyzed using GC-MS, methanol and chloroform with shaker extraction for 36 h. Then extracted lipids were derivatization with H2SO4 in methanol with n-hexane. Standard methods were used and then Identification of individual FAs by comparison of their mass spectra with the internal reference mass spectra library (NIST-11). The results of sesame seed among two varieties samples mean total flavonoids content, total phenolic content and IC50 values could have high antioxidant activity of DPPH free radical scavenging content ranged from (2.13±0.03 to 4.99±0.03 mg CE/g), (2.95±0.04 to 6.96±0.03 mg GAE/g) and (8.23±3.59 to 16.5 ± 0.92 µg AAE/mg) respectively. The maximum total flavonoids and total phenolic were obtained by 80% methanol extract. These results showed that there was a significant difference at (p &lt; 0.05) between the sesame seeds varieties were determined. Metema white sesame seed has a high content of total flavonoids, total phenolic and antioxidant activity than other sesame seed varieties. The present study provided that sesame seeds varieties were analyzed by GC-MS and nine FAs identified for each samples. The results showed that the major fatty acid present in sesame seeds varieties are linoleic acid (C18:2) (42.49 to 44.31 %), oleic acid (C18:1) (37.19 to 38.95 %), palmitic acid (C16:0) (9.345 to 11.186 %) and stearic acid (C18:0) (5.78 to 6.523 %) were presented in sesame seed varieties samples. The individual and the total concentrations of FAs of sesame seeds in Metema white sesame seed was higher than other sesame seed varieties whole West Armachiho black sesame seed was lower than that of other sesame seed Varieties.