[01] Akwasi Acheampong, Department of Chemistry, College of Science, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. [02] Mercy Badu, Department of Chemistry, College of Science, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. [03] Andrew Yirenkyi Agyemang, Department of Chemistry, College of Science, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.

Fruits and vegetables are known to have free radical scavenging abilities due to the antioxidants in them and this gives them the ability to prevent diseases and sicknesses. This study was carried out to investigate the total phenolic content and free radical scavenging abilities of some selected vegetables and to determine their minimum inhibitory concentration (IC₅₀). These vegetables include Solanum torvum, Xanthosoma colocasia, and Allium ascalonicum Linn. The total antioxidant capacity (TAC), total phenol content (TPC), ferric reducing antioxidant power (FRAP) and the DPPH scavenging assays of the methanolic extracts of samples were determined. The results for the total antioxidant capacity of the measured concentration (0.1-0.3 mg/mL) were 0.146 ± 0.00004, 0.102 ± 0.00006, and 0.085±0.00003 mg AAE/g respectively for Solanum torvum, Allium ascalonicum Linn and Xanthosoma colocasia. Total phenolic content values were 0.180±0.00015, 0.124±0.00008, and 0.102±0.00003 mg TAE/g for Solanum torvum, Allium ascalonicum Linn and Xanthosoma colocasia respectively. There was a perfect correlation between total antioxidant capacity (TAC) and total phenolic content (TPC) of the extracts with r² =1 and p<0.001. Solanum torvum exhibited the highest ferric reducing antioxidant power with values ranging from 0.013919 to 0.1464 mg GAE/DW for the concentration range of 0.1–3 mg/mL. Solanum torvum, Allium ascalonicum and Xanthosoma colocasia had IC₅₀ values of 1.0676, 1.5978, and 1.6753 mg GAE/DW respectively. Percentage scavenging ability were 78.60, 63.41 and 58.95 respectively for Solanum torvum, Allium ascalonicum L., and Xanthosoma colocasia at 3 mg/mL concentration. The results indicate that all the vegetables exhibit antioxidant capacities and Solanum torvum is a significant source of antioxidants.

Minimum Inhibitory Concentration (IC₅₀), Antioxidant Activity, Scavenging Ability, Total Phenolic Content

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