Abstract

Kumquat, known as the little jewel of the citrus family, is a fruit of the plant Citrus japonica Thunb. or Fortunella japonica Swingle. Kumquat is widely grown for its fruit, but such parts of the plant as leaves and bark are left as waste without being utilized. Therefore, we aimed to determine the chemical composition of essential oils from kumquat fruit and leaves (main species and 6 mutants) grown at the Mersin Alata Horticultural Research Institute.
The fruits and leaves of Citrus fortunella trees were collected and their essential oils were obtained by hydrodistillation. Gas chromatography-mass spectrometry (GC-MS) was performed to analyze the components of the essential oils.
Among the essential oil components determined by GC-MS analysis, limonene (69.9–94.4%) was detected at the highest levels in the fruit essential oil, while the leaf essential oil was rich in elemol (13.2–14.8%), ß-eudesmol (9.3–11.0%), α-guaiol (8.5–10.8%), spathulenol (8.1–10.5%), and alismol (6.5–7.9%). Our results showed that essential oil can be produced as a by-product from the leaves and fruits of C. fortunella trees.
Kumquat fruit and leaf essential oils contain large amounts of chemical components with potential biological activity, both major and minor. Therefore, they can be used as an herbal resource in different industrial fields such as medicine, perfumery, and cosmetics.

Keywords

Kumquat, Citrus fortunella, essential oils, limonene, elemol, ß-eudesmol, α-guainol, spathulenol, alismol

FUNDING

The authors thank İnönü University, Turkey for financial suppor t (BAPB – Grant No. TYL-2018-1108).

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