Comparative Study on Yields, Chemical Compositions, Antioxidant and Antimicrobial Activities of Cumin (Cuminum cyminum L.) Seed Essential Oils from Different Geographic Origins

The current study aimed to investigate the essential oil yields, chemical compositions, antioxidant and antimicrobial activities of cumin (Cuminum cyminum L.) seeds collected from India (Mehsana province and Banaskantha district of Gujarat), Morocco (Tinghir province), Iran (Khorasan province), Syria (Homs province), Turkey (Ankara province), Pakistan (Kalat province), Iraq (Basra province) and Afghanistan (Helmand and Balkh provinces). No previous studies were found for cumin seed essential oils from Afghanistan and Iraq so this could be considered as the first report. The essential oil yields were ranging between 1.16 % and 1.98 %. According to the chemical compositions, two chemotypes were identified as p-mentha-1,4,-dien- 7-al, and cumin aldehyde. Cumin aldehyde was dominant in Indian-originated seeds (39.3-46.5 %) and p-mentha-1,4,-dien-7-al was the major component (42.1-58.8 %) of the rest. All essential oils performed moderate antioxidant properties (IC50 values of 23.3-32.4 mu g/mL for DPPH and 65-73 % inhibition for beta-carotene/ linoleic acid tests) and high antimicrobial activities. Correlation analysis demonstrated that amount of cumin aldehyde had a strong negative relation with DPPH activity and had a positive relationship with beta-carotene/linoleic acid assay inhibitions. The amount of cumin aldehyde also correlated positively with disk diffusion- based antimicrobial susceptibilities and had variable correlations with broth microdilution tests. The sum of two other major aldehydes (p-mentha-1,4-dien-7-al and p-mentha-1,3-dien-7-al) were found to have no statistically significant correlation with biological activities.