Figure 1: GC-MS total ion chromatography (TIC) of citrus essential oils in different experimental condition. I: lemon, II: orange. (A) control sample, stock storage well in the dark and dry environment, (B) after 2hr sunlight treatment sample, (C) H2O added (5:1, EO: H2O) and exposed to sunlight 2hr sample. Blue number: original identified compound before treatment; red number: new appeared compound after treatment; green number: disappeared compound after treatment.