Ginger, Cumin Antioxidant Activity Studied

CAIRO, EgyptSpices do more than add flavor to food. Theyve long been prized for their numerous natural health benefits. Two spicesginger and cuminwere the focus of a recent study published in the Journal of Agricultural and Food Chemistry.

Ginger is believed to ease a range of ailments, including digestion problems, inflammation, arthritis, migraines and congestion, and is said to stimulate circulation and perhaps reduce cholesterol absorption. Cumin also is believed to play a role in digestive health, is thought to ease cold symptoms and may have anti-carcinogenic properties.

For this study, researchers evaluated the chemical and antioxidant activity of ginger (Zingiber officinale) and cumin (Cuminum cyminum). Cumin was found to have the highest yield for volatile oil ( 2.52 ± 0.11%), while the fresh ginger showed the lowest yield (0.31 ± 0.08%). In an analysis of the volatile oils of fresh and dried ginger, camphene, p-cineole, -terpineol, zingiberene and pentadecanoic acid were revealed to be major components. Major components in the volatile oil of cumin were cuminal, -terpinene and pinocarveol.

The highest yield of nonvolatile extracts came from the methanol extract of cumin (4.08 ± 0.17% w/w), while the n-hexane extract of fresh ginger showed the lowest yield (0.52 ± 0.03% w/w). Maximum total phenolic contents were observed in the methanol extract of fresh ginger (95.2 mg/g dry extract) followed by the hexane extract of fresh ginger (87.5 mg/g dry extract). The hexane extract of cumin showed the lowest total phenolic content (10.6 mg/g dry extract). The DPPH method showed the highest antioxidant activity for cumin essential oil (85.44 ± 0.50%), followed by dried ginger essential oil (83.87 ± 0.50%) and fresh ginger essential oil (83.03 ± 0.54%). The FRAP of essential oils showed almost comparative results with DPPH.

Cumin essential oil was found to be most effective in reducing Fe3+ ions, followed by dried and fresh ginger. The researchers concluded that ginger and cumin are viable sources of natural antioxidants for use in foods.