Pola produksi pigmen monascus oleh monascus sp. KJR 2 pada media biji durian varietas petruk melalui fermentasi padat

Angkak (red yeast rice) is rice fermented by Monascus sp. Monascus sp. KJR 2 is an isolate from red yeast rice in Kertajaya area. Based on previous study, it is known that KJR 2 is a potential isolate to produce pigments. Traditionally, Monascus sp. is grown on rice or bread through solid state fermentation. There is no research has been made so far to utilize durian seeds as substrate for pigment production. Petruk durian is kind of tropical fruit that developed in Indonesia. Chemical composition of Petruk durian seeds are 33.68% of starch, 4.13% of protein, 1.00% of fat, 1.62% of minerals, and 84.06% of moisture in dry basis. Secondary metabolite production such as pigment is correlated with cell growth. Some research showed a different result in Monascus sp. pigment production model on different media and strain. Therefore, a model of Monascus sp. KJR 2 pigments production on Petruk durian seeds are investigated in this study. A sorted Petruk durian seeds were boiled in Ca(OH)2, washed, and peeled-off the skin. Durian seeds were cut into cubes (±1 cm3), sterilized, and inoculated with Monascus sp. KJR 2 starter culture. It was incubated for 16 days with sampling on 4th, 6th, 8th, 10th, 12th, 14th, and 16th days and was analyzed for the ethanol-soluble pigments, water-soluble pigments, and Total Mould. This study was conducted with four (4) replications and regression analysis was used to determine the correlation between fermentation time and Monascus sp. KJR 2 pigments production. Growth of Monascus sp. KJR 2 increased up to 4th day (6,4592 log cfu/g), stationary phase occurred at 6th day (6,3532 log cfu/g) up to 12th day (6,7213 log cfu/g), and death phase begin at 14th day (6,5944 log cfu/g). Production of ethanol-soluble red and yellow pigments increased up to 10th day (1,032 AU/g and 0,866 AU/g), whereas production of orange pigments up to 12th day (0,573 AU/g). Production of water-soluble yellow, orange, and red pigments increased up to 14th day with yields at 6,458 AU/g, 3,781 AU/g, and 3,265 AU/g. A model of ethanol-soluble and water-soluble pigment production of Monascus sp. KJR 2 which growth on Petruk durian seeds is similar to cubic curve type