Executive Summary : | Objective: Scale-up process for isolation of ricinoleic acid from castor oil; Scale-up process for biotransformation of ricinoleic acid to (+)-g-decalactone using bioreactor; Cost-economics study of the scale-up processes Summary: Castor (Ricinus communis), a non-edible oil-seed and India produced ca. 85% of World’s castor oil. This oil contains ricinoleic acid (80%) as a major compound. The motivation behind R&D on castor oil originated after Honorable Prime Minister of India emphasized its value addition in CSIR society meeting two years back. (+)-?-Decalactone, an important food-flavor with GRAS status is obtained from ricinoleic acid through microbial biotransformation. (+)-?-Decalactone can generates a variety of food-flavors viz., stone fruit flavors (peach, plum, apricot, cherry, etc), berry flavors (strawberry, raspberry, blackberry, etc) and tropical fruits flavors (mango, guava,
pineapple, etc), when used in different concentrations (ppm). As it is produced through biotransformation, therefore, it is classified as natural. In literature, 31% of ?-decalactone conversion has been reported in about 10 days (240 h) of fermentation. ?-Decalactone produced through biotransformation costs USD300 (Rs 20,000/ kg), whereas chemical synthesis route costs USD150 (Rs 10,000/ kg) (Braga, World J Microbiol Biotechnol, 2016, 32, 269). In chemical synthesis route is produced 50:50 enantiomeric ratio of (+)-?-decalactone as well as (-)-?- decalactone, but only (+)-?-decalactone having important flavour characteristics. Recently, some major companies like Cadbury, Symrise, Johnson & Johnson, etc have introduced some decalactone based food-flavor products. Presently, we have developed a process using a new Candida strain (non-pathogenic, safe) for significantly enhancing (more than two fold) the yield of (+)-?-decalactone from ricinoleic acid. Present process comprised of two steps; I) An economical process for the enrichment of ricinoleic acid (94-97%) from castor oil through solvent-solvent partition, II) This enriched ricinoleic acid is bio-transformed into (+)-?-decalactone using new isolated Candida strain. More than 70% of purified (+)-?-decalactone is obtained from ricinoleic acid in 60-80 h of inoculation. Chiral-GC-FID analysis revealed that it possessed 99% of enantiomerically pure food-flavor important (+)-?-decalactone. In-vivo study of this Candia strain for 7 days found that the animals did not exhibit any symptoms of toxicity in observational parameters and also homogenates from the organs collected did not yield any colonies in the media upon incubation, thus concluding the fact that the present strain was not pathogenic in nature. On the basis of these laboratory studies, we propose scale-up (1.0 kg of castor oil) production of (+)-?- decalactone from ricinoleic acid using bioreactor. Cost-economics evaluation of bench scale study will be carried out for commercial application On the basis of these laboratory studies; we propose scale-up (1.0 kg of castor oil) production of (+)-?-decalactone from ricinoleic acid using bioreactor. |