nomilin

Nomilin is a natural chemical compound belonging to the limonoid family, a group of oxygenated tetranortriterpenoids found in citrus fruits. It occurs mainly in the seeds and peels of Citrus species, and is particularly associated with bitter varieties such as bitter orange. Nomilin contributes to the characteristic bitterness of some citrus by-products and can be present in juice and essential oil fractions.

Chemically, nomilin is an irregular triterpenoid with the limonoid skeleton. Like other limonoids, it is derived from the citrus biosynthetic pathway and can be isolated from plant material using organic solvent extraction and chromatographic methods.

Biological activity: In laboratory studies, nomilin has shown a range of activities, including antimicrobial and antiviral effects, anti-inflammatory activity, and cytotoxic effects against certain cancer cell lines. It has also been reported to act as an insect antifeedant. However, results are preliminary; most evidence comes from in vitro experiments or animal models, and there is no clinical evidence of therapeutic benefit.

Applications and safety: Nomilin is primarily of interest as part of the broader class of citrus limonoids and as a component of citrus by-product extracts used in functional foods or nutraceutical research. High concentrations may impart bitterness and the safety of concentrated nomilin preparations has not been established for human use.

See also: Limonoids; Citrus essential oils; Limonin.