| Summary: | This study was done in order to determine the presence of antioxidant and the level of
antioxidant activity of garlic (Allium sativum) and shallot (Allium cepa). Garlic and shallot
have been the most common ingredients in the preparation of Malaysian cuisines and it has
been long-held belief that these two Allium species posses many medicinal properties
including the antioxidants properties. Samples of A. sativum and A. cepa used in this study
were collected from the markets around Kuantan area, Pahang, Malaysia. Total phenolic
content (TPC) assay and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay were included as the
main methods. The TPC assay was conducted to examine the presence and concentration of
phenolics as this compound possesses antioxidant characteristics while the activity of primary
antioxidants were determined using the DPPH assay. The TPC results indicated that the
concentrations of total phenolics were higher in A. cepa (53.43±1.72 mg/L) as compared to A.
sativum (37.60 ± 2.31 mg/L). Furthermore, the DPPH results showed that among the two
Allium species, A. sativum expressed higher antioxidant activity than A. cepa. The percentage
of scavenging activity for A. sativum reached up to 53.11 ± 3.04% while the highest
percentage for A. cepa was 36.05 ± 3.04%. Overall, there was poor correlation between the
total phenolics contents and the antioxidant activity by DPPH radical scavenger showing that
the antioxidant activity of both Allium species extracts is not solely due to the phenolics
compounds. Apart from that, Ferrous ion cgelating activity assay was conducted in order to
determine the ion chelating effect of the sample. Derived from the findings of the assay
shows that A.cepa shows as higher ion chelating effect compared the to A. sativum, 45.00 ±
1.73% and 43.29 ± 3.89 % respectively. However, in order to strengthen the validity of the
current results and to further assess the potential of Allium species as natural antioxidant
sources, ferric reducing antioxidant power (FRAP) assay can be conducted for future work.
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