Family Rutaceae
Dayap
Citrus aurantifolia (Christm.) Swingle
LIME

Other scientific names   Common names 
C. acida  Bilolo (Tag.) 
C. acidissima Dalaya (Ibn.) 
C. bergamia Dalayap (Ilk., Pamp., P. Bis.) 
C. excelsa Dulugot (Neg.) 
C. javanica  Gorong-gorong (Ilk.) 
C. lima  Gugulo (If.) 
C. limetta  Lime (Engl.) 
C. notissima  Limon (Span.) 
Limonia acidissima  Muyong (Bon.) 
Limonia aurantifolia  Sua (Bik.) 
Limonia spinosum   

Botany
Small tree or shrub, 2-4 meters high, smooth throughout, branching with slender, solitary, sharp spines 1 cm or less. Leaves are oblong-ovate to elliptic-ovate, 4-6 cm long. Petioles are 1-1.5 cm long. Racemes are short, bearing few flowers, white and fragrant. Petals are 4, oblong, 10-12 mm long. The fruit is almost spherical, 3-5 cm in diameter, yellow, thin-skinned, 10-celled or more.

Distribution
Planted throughout the Philippines in settled areas.

Constituents and properties
Pulp: citric acid, 4.24%; protein, 0.94%; sugar, 0.5%.
Juice: citric acid, 7.67%; vitamin C.
Juice is regarded as antiseptic, tonic, antiscorbutic, astringent, diuretic.
Root bark is febrifuge.

Parts utilized
Fruit, roots, bark, rind.

Uses
Folkloric
Nausea and fainting: Squeeze rind near nostril for irritant inhalation.
Decoction of roots used for dysentery; root-bark as febrifuge.
Crushed leaves applied to forehead for headaches.
Leaf decoction for eyewash and to bathe a feverish patient.
Mouthwash and gargle for sore throat and thrush.
Externally, fresh juice is used to clean wounds; roasted, for chronic sores.
Juice used for irritation and swelling of mosquito bites.
Poultice of leaves applied to ulcer wounds.
Poultice of leaves for skin diseases or on the abdomen after childbirth.
In southwest Nigeria, roots, bark, stem, twigs, leaves and fruit used in treatment of malaria.
Others
Flavor: Use juice and grated rind. A pleasant ade.
Substitute for true lemon.
Good source of vitamin C.
As fumigant, steaming brew of leaves under the blanket.
Lime oil is extracted by steam distillation of the fruit rinds; used for colds, sore throats, bronchitis, asthma. Also for arthritis, obesity, cellulite and as tonic and astringent.

Studies
Essential oils / Antifungal:
Study on essential oils of three varieties of C. aurantifolia showed the plant to be very rich in monoterpenes, with limonene its major compound. The three extracts showed fungicidal inhibiting action to Phaeoramularia angolensis and presents an alternative to chemical fungicides used for Citrus fruit crops.
Antiproliferative / Anti-cancer:
Study of in vitro effects of several concentrations of lime juice (CLJ) showed significant inhibition of proliferation of human breast carcinoma cell line and assumes that protein components of the CLJ extract may have anti-proliferative effects on tumor cell lines.
Antimicrobial: Study investigating the antibacterial effects of two plants extracts showed Citrus aurantifolia showing promising borad spectrum antibacterial effects on human pathogens.
Antiaflatoxigenic: The essential oils of we medicinal plants were studied for its inhibition ofthe toxigenic fungus Aspergillus parasiticus.Citrus aurantifolia was found to inhibit both A. parasiticus and aflatoxin production. The study suggests some medicinal plants may be potential candidates for protection of food and feeds from toxigenic fungus growth and subsequent AF contamination.
Antiproliferative / Colon Cancer Prevention: Study of the lime volatile oil of CA yielded 22 compounds, D-limonene, D-dihydrocarvone among the major componds. The oil showed 78% inhibition of human colon cancer cells, DNA fragmentation and apoptosis induction, results that suggested potential antiproliferative benefits in colon cancer prevention.

Availability
Commercial cultivation. 
Extracts, essential oils and supplements in the cybermarket.



Additional Sources and Suggested Readings
(1)
Essential oils of Citrus aurantifolia from Cameroon and their antifungal activity against Phaeoramularia angolensis / P. M. Jazet Dongmo et al / African Journal of Agricultural Research Vol. 4 (4), pp. 354-358 April, 2009
(2)
Effects of concentrated extract on the spontaneous proliferation of MDA-MB-453 and RPMI-8866 tumor cell lines / Phytomedicine, Volume 9, Issue 5, Pages 475-477 /
(3)
In vitro Antimicrobial Activity of Crude Extracts of C. aurantifolia and Tithonia diversifolia on Clinical Bacterial Isolates / S. S. Taiwo et al / International Journ of Tropical Med 2(4):113-117,2007
(4)
Chemical composition and antiaflatoxigenic activity of Carum carvi L., Thymus vulgaris and Citrus aurantifolia essential oils / Food Control / Vol 20, Issue 11, November 2009, Pages 1018-1024 / doi:10.1016/j.foodcont.2008.12.007
(5)
Apoptosis-mediated proliferation inhibition of human colon cancer cells by volatile principles of Citrus aurantifolia / Food Chemistry
Volume 114, Issue 4, 15 June 2009, Pages 1351-1358 / doi:10.1016/j.foodchem.2008.11.033