RESUMEN
Pullulan is a linear glucosic polysaccharide produced by the polymorphic fungus Aureobasidium Pullulans, which has long been applied for various applications in medical and food industry due to its security, stability and low adhesive ability.At present, the two problems in restricting pullulan industrial production are the low polysaccharide production and melanin secreted which is hard to erase completely, giving the following process some problem.As a starting point, this review article collects and analyzes the progress on the breeding of pullulan high-yield strain without melanin in recent years, in order to find more efficient strains breeding methods, laying a foundation for further breeding of pullulan high-yield strain without melanin.
RESUMEN
A highly phytase-producing strain B.licheniformis LL8 was obtained by several mutagenesis of UV with B.licheniformis as starting strain.The new strain produced about two folds of phytase activity as compared with the starting strain. The production performance of the strain was stable. The cultivation conditions were optimized by single factor and orthogonal experiment. When the mutant B.licheniformis LL8 was cultivated at 55℃, initial pH 7.5 with the inoculation size of 10% for 30h in WBE medUm, the phytase activity was up to 2268.4U/mL.
RESUMEN
The results of isolation,screening and identification of Bacillus subtilis strains which produced fibronolysion were reported in this paper.20 Bacillus subtilis strains were screened from different withered straw samples.Among them,FM-S1,FM-S2,FM-S6,FM-S8 and FM-S11 produce fibronolysin with higher activity.According to morphological,physiological and biochemical characters,the screened strains were confirmed to be Bacillus subtilis. For FM-S2,the production of fibronolysin type in solid fermentation was considered to be synchronous with growth.