The present work was designed to investigate the presence of bioactive chemicals in the reaction mixtures (RMs) of peels of Valencia, Mandarin, and African navel oranges, through GC-MS and FT-IR studies. Limonene, a unique compound, is present in the RMs of the three orange peels. Moreover, hexadecanoic acid 2-hydroxy-1-(hydroxymethyl) ethyl ester was identified in the RMs of all the three-orange peels. The RM of Mandarin orange exhibited potent cytotoxic effect against MCF-7 ATCC human breast cancer cells (HBC). All the three RMs exhibited moderate antibacterial activity against the human pathogenic bacteria Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 12228), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (ATCC 700603), Salmonella choleraesis (ATCC 10708), Pseudomonas aeruginosa (ATCC 27853), and Proteus mirabilis (ATCC 299).