The Effect of Corn Cob Size as a Substrate and Fermentation Time on Carotenoid Production by Neurospora sitophila

Chemical Engineering Department, Engineering Faculty, Sebelas Maret University, Surakarta, Indonesia 57126

^* Corresponding author: aidaramadhani@staff.uns.ac.id

Abstract

Natural pigments are recommended to reduce the use of synthetic pigments, one of which is the primary color yellow. Carotenoids are natural yellow to red pigments that are produced naturally by plants and microorganisms. Fermentation of carotenoids by the microorganism Neurospora sitophila is one solution to the challenges of plant based pigment which compete with the needs of food, land, and dependence on weather and seasons. Corn cobs are one of the cellulotic wastes that can be used as a carbon source. This research aims to examine the effect of corn cob size (60, 20, 8 mesh) and fermentation time (3, 6, 9 days) on the carotenoid pigments produced. The spectrophotometer analysis show that fermentation increase the initial carotenoids concentration in corn cobs. The smaller the substrate and the longer fermentation time, the greater the concentration of carotenoids produced. The highest concentration was obtained on 60 mesh substrate with 9 days fermentation at 31.79 ppm. FTIR analysis shows the presence of carotenoid pigments by the C=C and C-H, and the O-H functional group which represent zeaxanthin, astaxanthin and neurosporaxanthin compounds. Based on SEM test results, the average particle size of corn cob powder was 50 μm with porosity of 67.93%.