Sorghum ( Sorghum bicolor ) Grain Antioxidant Scavenging Activity on Stored Finger Millet ( Eleusine coracana ) Derived Yeast Under Laboratory Conditions

There is increased interest in the study and application of finger millet derived yeast (FM), especially in bioethanol industry. Several studies have shown the vitality of this yeast, but its preservation has been a challenge hindering its wider application. Natural antioxidant sources such as sorghum are promising non-toxic preservatives with strong radical scavenging activity. However, it is unknown whether its antioxidants have no side effects on FM, or can extend its shelf life. This study aimed at analysing sorghum grain extracts (SEs) antioxidant activity in terms of their antioxidant content and activity to preserve these yeasts, in small or large quantities for laboratory or industrial applications. Acombination of in vitro and in vivo methods were used to determine the antioxidant potential of SEs, and high performance liquid chromatography for compound characterization. The highest total phenolic content was recorded in K71S2814 (76.25) and lowest in KARI MATIMA1 (43.57) in mgGAE /100gdm, and that of total flavonoid content was reported in GBK006801 (37.31), and lowest in K15 OCHUTI (10.14) in mgCE /100gdm. The highest radical scavenging activity (IC 50 ) was reported in GBK006801 (25.82ug/ml), and lowest in GBK032096 (86.01ug/ml), GBK006801 (25.82), ( Severe≥5density ) and K71S2814 (44.11), ( Severe≥5density ) had higher in vitro and in vivo antioxidant activity than ASCORBIC ACID (46.25) ( moderate survival ≤2.5density ). Epigallocatechin gallate (0.002939-0.035139%), and epicatechin gallate (0.007525-0.251397%) very powerful antioxidants than ascorbic acid were isolated. Based on the study, it is concluded that sorghum is non-toxic, with antioxidants that can significantly extend FM shelf life.