Botany: Lime is an evergreen tree of the genus Citrus (family Rutaceae) with stiff sharp spines. It grows up to about 4.5 m high. The leaves are medium sized, ovate, bluntly pointed, at tips, rounded to cuneate at base. Flowers are large and fragrant. Fruits are small, oval to round, with a thin rind. If they ripen on the tree, the fruits are golden-brown to slightly orange colour, but normally the fruits are collected when they are green and are more tasty and juicy. Slices are very fragrant with a sour taste, as they contain up to 6% citric acid. While all other citrus trees are subtropical crops, the lime tree is a real tropical tree, native to southern Asia (Malaysia and India). Today it is cultivated mainly in Southeast Asia, south Florida, Central America (Mexico) and the West Indies (e.g. Cuba).
The parts used are the fresh peel of the green unripe fruit, or the whole crushed fruit.
History and/or folklore: The rind of immature fruit, beaten into a pulp, may be applied to the eyelids to cure sore eyes. The juice was used as an antiseptic by the Creoles of the Antilles. Arexa (Waimiri Atroari), a drink made from fruits, is recognised as a cold cure. The Wayapi Indians of French Guiana rub the mashed leaves on the forehead for headaches.
Lime (as with other citric fruits) is an antiscorbutic. ‘Limey’, an old slang nickname for the British, originally referring to their sailors, is believed to derive from the practice of the Royal Navy and Merchant Navy of supplying lime juice to British sailors to prevent scurvy.
Biochemistry: Distilled lime oil contains large amount of terpene hydrocarbons (e.g. δ-limonene), oxygenated compounds (citral, terpineol, cineol, and linalool), and germacrene B (and important fragrance component with a sweet, wood-spicy, geranium like note).
Expressed (cold-pressed) lime oils contain similar constituents as the distilled oil, but also anthranilates and substituted coumarins (such as limettin and bergapten).
Citrus aurantifolia essential oil – Lime oil
Lime oil is obtained by cold expression (expressed lime oil) of fresh peel of the green unripe fruit, or steam distillation of the whole crushed fruit, or juice of the crushed fruit (distilled lime oil). Centrifuged lime oil is obtained by centrifuging the pulp and the mixture of the fruit in high speed centrifuge thus separating the oil from the pulp.
Lime oil acts like lemon and other citrus oils. It has antiscorbutic activity and it is a refrigerant. Lime juice is a traditional source of vitamin C but limes are used more as a flavouring than medicinally.
Citrus aurantifolia essential oil
Rich in essential fatty acids, lime oil gives emollient and protective properties to skin care products. The aroma enhances and enlivens the mood, energizes and can help relieve fatigue and stimulate mental activity and memory. Lime oil is extensively used in food flavouring.
The expressed oil is used as fragrance components and fixatives (coumarins). It is used in creams, lotions, soaps, detergents, perfumes and massage oils at a maximum level of 1.5 %.
Lime oil has a mosquito repellent effect that lasts up to 5 hours; it also has insecticidal activity against mosquitoes, cockroaches and houseflies.
Do not use lime oil on the skin in direct sunlight; however, if essential oil of lime is distilled rather than expressed, then it does not have a phototoxic effect.