Breeding For The High-yield Red Pigment Strains Of Monascus By The Mutagenesis Of Physics And Chemistry And The Study For Liquid-fermentation

Monascus has been used in food fermentation for thousands years in china, The Physiologically active substance that Monascus produced had been researched widely, Monascus red pigment is a natural excellent substance. It is playing more and more important poles in modern food industry. There are two main ways for the production of monascus red pigment, one is solid fermentation, the other is liquid fermentation. Liquid fermentation is the main trend in the production of Monascus red pigment.This dissertation main includes the following contents:1. Seperating and choosing high-yield red pigment Monascus from red rice with three kinds of way in Seperating technique. The method of directly separating from the red rice is easy to master and widly used by farmer, but Its seperating result is not ideal. The method of serperating from collecting spore is difficult to master,though Its serperating result is excellent. The method of separating from spore is easy to master and its result is also excellent. so it is choosed as the separating method.2.Through the method of separating from spore,six strains of Monascus which include SZ1, SZ2, SZ3, SZ4, SZ5, SZ6,is separated from the red rice. Comparied their red value, SZ4 was choosed as the original strain. Its red value is 10.8u/mL.3. Breeding for the High-yield red pigment Strains of Monascus by the Mutagenesis of UV and LiCI as SZ4 was the original strain, Five strains was found.That is SZ401, SZ402, SZ403, SZ404, SZ405. Comparied their red valueSZ401 was choosed as the product Monascus strain.Its red value is 20. 2u/mL.4. Effect of different culture medium on yield of mononscus was studied by single factor test and orthogonal experiments. The results showed that the best culture medium for SZ401 were as follows: rice powder 9%, NaN0₃ 0. 2%, KH₂P0₄ 0. 1%, MgS0₄ 0. 2%. In this condition, the red value of SZ401 is improved to 57. 0u/mL.5. The culture conditions for producing monascus pigment by Monascus SZ401 were studied. The optimum cultivating conditions were: fermentation period 3d, temperature 32℃, seeding volume 5 %(v/v), filled volume 70mL/500mL flask, rotated speed 24r/min, initial pH3. 8. In this condition, the red value of SZ401 is improved to 84.0u/mL.