The aim of this study was to determine the antioxidant capacity of some phytochemicals by using an H2O2 scavenging assay. Betaine, Allantoin and Nicotinamide were put to the test. Even though hydrogen peroxide (H2O2) is not intrinsically reactive, it can be transformed into the extremely reactive and harmful hydroxyl radical (HO), which is then able to interact with nucleotides in deoxyribose nucleic acid and in that way trigger breakage of the strand resulting in carcinogenesis, mutagenesis, etc. Antioxidants aid in the protection of cells from the harmful effects of reactive oxygen species that are known to induce oxidative stress. Excessive production of these reactive oxygen species in the human body is associated with many chronic degenerative diseases such as diabetes, neurodegenerative disease, cancer, etc. The effective way to minimize levels of oxidative stress is the ability to scavenge these reactive oxygen species (ROS). Also, phytochemicals are able to act as antioxidants, and in that way play a vital role in the prevention of disease caused by oxidative stress. The ability of a compound to scavenge H2O2 is a good predictor of its potential antioxidant function. The hydrogen peroxide (H2O2) scavenging assay was determined using the Ruch et al., 1989 method, and a UV-VIS spectrophotometer. In conclusion, our samples had marvellous H2O2 scavenging activity and possessed good antioxidant capability, and were compared with the ascorbic acid (vitamin c) as standard natural antioxidant/ as reference antioxidant. The samples were also able to scavenge H2O2 in a concentration-dependent way, according to our results