Research Abstract
Most of the synthetic dyes found to be hazardous to human health therefore; we need to develop alternative source of natural food colorants. The current study aimed to study different factors affecting on pigment production by Monascus purpureus. The optimal growth and pigment production factors were carbon and nitrogen source (Corn starch & yeast extract), medium pH 6 after fermentation time 12 days under shaking (150 rpm) at 30 ± 1 °C. The impact of testing different amino acids, metal ions and vitamins addition to the medium was explored by applying (100 μg/l) for each of them on the medium. The addition of Tryptophan was effective and enhanced both growth and production (3.9 g/l dry mass and 2.376 A500), Manganese improve growth and production with 4.6 g/l dry mass and 1.997 A500 and the addition of ascorbic acid also increase the production (4 g/l dry mass and 2.652 A500). The isolate seems to be tolerated the salinity stress until 2% for growth and production then production decrease until it stops completely at 6% NaCl. Maximum optical density values of red yeast pigment recorded at wavelength 500nm followed by 460nm. Red pigment shows various optical density values in different solutions (salicylic acid; citric acid and ascorbic acid. Testing different factors affecting on production is an efficient approach for the production of pigment through microbial fermentation by Monascus purpureus and could be utilized in industrial application.
