Luffa is a genus of tropical and subtropical vines in the Cucurbitaceae family. It grows as a flowering annual vine. In everyday non-technical usage, the luffa, also spelled loofah, usually means the fruit of the two species L. aegyptiaca and L. acutangula. Genus name was derived from the product “Loofah” used as bathing sponges, scrubber pads, doormats, pillows, mattresses, cleaning utensils. The plant name "Luffa" was introduced to Western botany nomenclature by the botanist Johann Vesling, who visited Egypt in the late 1620s and described the plant under cultivation with artificial irrigation in Egypt. In 1706 the botanist Joseph Pitton de Tournefort introduced the formal botany genus name "Luffa". In establishing the Luffa genus, Tournefort identified just one member species and called it "Luffa arabum". His 1706 article includes detailed drawings of this species (which is now called Luffa aegyptiaca). Origin of ridge gourd is not known. Smooth gourd may be a native of South Asia or Africa or Australia. The Luffa has essentially Old World origin in subtropical Asian region including particularly India. The origin of the Luffa (loofah) sponge is unknown as to where exactly it came from, but most scientists believe it originated in Asia or Africa and actual cultivation first started in India. Indo-Burma is reported to be the centre of diversity for sponge gourd. The young fruit is eaten as a vegetable and is commonly grown for that purpose in tropical Asia. Unlike the young fruit, the fully ripened fruit is strongly fibrous and inedible, and is used to make scrubbing bath sponges. The young shoots, flowers and leaves can be cooked, and the mature seeds can be roasted for consumption. An edible oil can be extracted from the seeds. The resulting oil meal can be fed to rabbits and catfish, or used as a fertilizer. Smooth luffa (Luffa aegyptiaca) produces pretty yellow flowers which are both showy and conspicuous, about 5-7.6 cm across with five petals. The fruits are green, up to 61 cm long and 7.6 cm in diameter; they are cylindrical and smooth, and shaped like a club, slighter wider on one end. Small fruits look like okra or little cucumbers. On older fruits, the outer skin eventually dries and turns brown and papery. Ridged loofah (Luffa acutangula), or "vine okra", is a similar species which has light yellow/white flowers and produces gourds that are ridged with ten angles. Vine okra is harder to peel for the sponge. The fruit section of L. aegyptiaca may be allowed to mature and used as a bath or kitchen sponge after being processed to remove everything except the network of xylem fibers. If the loofah is allowed to fully ripen and then dried on the vine, the flesh disappears leaving only the fibrous skeleton and seeds, which can be easily shaken out. In this review article origin, distribution, taxonomy, botanical description, genetic diversity, and breeding of Luffa spp. are discussed.
