REVIEW ON PHORBOL ESTER DEGRADATION OF JATROPHA SEED CAKE FOR ITS USE AS ANIMAL FEED

Abstract

Jatropha curcas is an oil-seed plant with good adaptability to grow in unfavourable conditions like infertile soil with scanty rainfall. It had been exploited for the extraction of oil for bio-diesel. The compressed seed cake, after the oil extraction, is a rich source of protein with certain toxic and anti-nutritional factors. The major toxins in the seed cake are phorbol esters and trypsin inhibitors that lead to various health problems if ingested. Even though the application of the various extracts carries a lot of beneficial advantages, yet the toxicity in oil and the compressed cake does not allow the by-products and the oil to be used elsewhere. Various physicochemical and biological methods have been described for the detoxification of Jatropha seed cake and oil of which the chemical extraction with methanol and ethanol have shown promising results in reducing the toxin contents by 97-100% while UV-irradiation reduced the phorbol esters completely. Submerged fermentation by Bacillus sp. achieved complete detoxification of phorbol esters within a week. A new strain was found to degrade the phorbol esters to phorbol, myristic acid and acetic acid within 12 h of incubation in submerged fermentation process. The detoxified products, in future, can be used as animal feed and food supplement to help utilize the by-products as a healthy diet.