The botanical name Euphorbia derives from the Greek Euphorbus, physician of king Juba II of Numibia (52-50 BC - 23 AD),
The state is rich in floral diversity as 1911 wild species belonging to 780 genera and 154 families are found here (Singh and Pandey, 1980, 1983, 1998; Katewa et al., 2004). The commonly used herbal medicines used by tribals of Rajasthan belongs to the families Euphorbiaceae, Fabaceae, Asteraceae, Apiiaceae, Cucurbitaceae, Acantheceae, Papaveraceae, Capparidaceae and Solanaceae (Sharma and Vyas, 1985; Shetty and Singh,1987; Joshi, 1991, 1994; Sharma, 2002; Parveen et al., 2007). The distribution of family Euphorbiaceae in Rajasthan is given in Fig 1.4. The family contains a large variety of phytotoxins, mainly diterpene esters, alkaloids, glycosides, and ricin-type toxins (Evans 1986a, 1986b), and their presence make it ethnobotanically and pharmacognostically important family. The botanical name Euphorbia derives from the Greek Euphorbus, physician of king Juba II of Numibia (52-50 BC - 23 AD), who might have used a certain plant in allusion to his swollen belly, possibly Euphorbia resinifera. In 1753, Carolus Linnaeus, the great taxonomist, assigned the name Euphorbia, to the entire genus. Euphorbiaceae is the name given to one of the largest families in the plant world, sometimes known as spurges. The Euphorbiaceae plants are mostly monoecious herbs, shrubs, and trees, sometimes succulent and cactus-like. Euphorbiaceae is one of the largest families of plant world, with about 300 genera and 7,500 species that are further characterized by the frequent occurrence of milky sap. This family occurs mainly in the tropics, with the majority of the species in the Indo-Malayan region and tropical America. However, Euphorbia also has many species in non-tropical areas such as the Mediterranean, the Middle East, South Africa, and southern USA (Radcliffe, 1986; Chellaiah et al., 2006). A number of plants of the Spurge family are of considerable economic importance and many are grown as ornamental plants. The plants are annual or perennial herbs, woody shrubs, or trees with a caustic, poisonous milky sap (latex). The roots are fine or thick and fleshy or tuberous. Many species are more or less succulent, thorny, or unarmed. The main stem and mostly the side arms of the succulent species are thick and fleshy, 15-91 cm tall. The deciduous leaves are opposite, alternate or in whorls. In succulent species, the leaves are mostly small and short-lived. The stipules are mostly small, partly transformed into spines or glands, or missing. Euphorbia is one of the largest genera of Euphorbiaceae, with approximately 2,000 species and having many potential plants. The variation within this genus is surprising; from low-growing garden weeds called as spurges, to giant cactus-like succulents. With the changing pattern of life style, most of the diseases are becoming life style diseases. Bursting of population, illegal and wrong practices of medicine, environmental pollution and various other causes have led the pathogens to acquire resistance. Phytochemical data provide much useful information concerning the presences of several groups of secondary metabolites (Mahlberg et al., 1988). Many members of the genus Euphorbia contain a poisonous milky-latex sap (Hegnauer, 1966a, 1989). Latex is a complex mixture of diterpenes, triterpenes, enzymes, amino acids, and other components. Several plants produce cis-polyisoprene (natural rubber) which has also been isolated from many Euphorbia spp. (Rizk, 1987). During the present course of study, investigations were carried out with the following objectives: • Ethnobotanical studies of Euphorbia spp. found in Rajasthan. • Phytochemical studies of E.hirta, E.tirucalli, E.thymifolia and E.pulcherrima: § Quantitative Phytochemical studies. § Qualitative Phytochemical studies. • Antimicrobial studies E.hirta, E.tirucalli, E.thymifolia and E.pulcherrima: § Antibacterial studies of some species. § Antifungal studies of some species.