Jatropha is a genus of approximately 175 succulent plants, shrubs and trees (some are deciduous, like Jatropha curcas), from the family Euphorbiaceae. The generic name is derived from the Greek words ἰατρός (iatros), meaning "physician," and τροφή (trophe), meaning "nutrition," hence the common name physic nut. Mature plants produce separate male and female flowers. As with many members of the family Euphorbiaceae, Jatropha contains compounds that are highly toxic.

Goldman Sachs recently cited Jatropha curcas as one of the best candidates for future biodiesel production. It is resistant to drought and pests, and produces seeds containing 27-40% oil, averaging 34.4%. The remaining press cake of jatropha seeds after oil extraction could also be considered for energy production. However, despite its abundance and use as an oil and reclamation plant, none of the Jatropha species have been properly domesticated and, as a result, its productivity is variable, and the long-term impact of its large-scale use on soil quality and the environment is unknown.

Jatropha curcas, also known as physic nut, piñoncillo and Habb-El-Melúk, is used to produce the non-edible Jatropha oil, for making candles and soap, and as a feedstock for producing biodiesel. Prior to pressing, the seed can be shelled with the Universal Nut Sheller which reduces the arduous task of removing the seeds from the shell by hand. Once the seeds have been pressed, the remaining cake can be used as feed in digesters and gasifiers to produce biogas for cooking and in engines, or be used for fertilizing, and sometimes even as animal fodder. The whole seed (with oil) can also be used in digesters to produce biogas. Large plantings and nurseries have been undertaken in India by many research institutions, and by women's self-help groups who use a system of microcredit to ease poverty among semi-literate Indian women./p>

See also:
http://en.wikipedia.org/wiki/Jatropha
http://en.wikipedia.org/wiki/Jatropha_oil

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