This study aims to elevate the physiological biochemical composition of Jatropha curcas L. via irrigation by the nutrient rich treated sewage water or sewage water + sludge. At the same time it might be considered as a stepping stone for the solution of the huge amount of sewage water that lost daily at the Drinking and Sewage Water Treatment Station in Al-Gabal Al-Asfar, Cairo, Egypt. Jatropha curcas is one of the best candidates of biodiesel production since its seeds contain oil which is practically participating in biodiesel production. Seed cake of Jatropha curcas (a waste by-product produced after oil extraction) contains considerable percentages of cellulose, hemicellulose and starch. The results indicated that, irrigation by sewage water and sewage water + sludge have been successfully increased the levels of photosynthetic pigments: chlorophyll (a), chlorophyll (b) and carotenoids and antioxidant enzymes: super oxide dismutase (SOD), catalase (CAT), poly phenol oxidase (PPO) and peroxidase (POX) in leaves. The estimated fractions of carbohydrates (total soluble sugars, polysaccharides, cellulose and hemicellulose), total soluble protein, total free amino acids, proline and lignin in addition to total phenols have been increased in leaves and seed cakes under irrigation by either sewage water or sewage water + sludge.
Key words: Jatropha curcas, Seed cake, Sewage water, Sewage sludge.