Effect of pellet size and stimulating factor on the glucosamine production using Aspergillus sp. BCRC 31742.

The higher GlcN production using a wild-type fungi, Aspergillus sp. BCRC 31742 cultivated under submerged fermentation was investigated. Several fermentation aspects were studied, such as pellet size, working volume, agitation rate and stimulating factor. Culture cultivation with conditions, such as pellet diameter of 2.15mm, 50mL working volume (250mL T-flask), incubation at 30 degrees C, 200rpm and pH 7.0 for 5days yielded highest biomass concentration which was 33.82g/L, with a GlcN concentration of 7.05g/L. Methanol was found to give the best stimulatory effect in terms of GlcN concentration as compared to glutamic acid, cycloheximide and ethanol. Addition of methanol (1.5%v/v) into fermentation medium could increase GlcN content from 0.21 (control) to 0.26g/gdw cells and led to maximum GlcN concentration of 7.48g/L obtained.

Determination and kinetics of producing glucosamine using fungi.

This work used three fungi, Rhizopus oligosorus BCRC 31996, Monascus pilosus BCRC31527, and Aspergillus sp. BCRC31742, to produce glucosamine by using submerged fermentation and flask cultures. The reaction of glucosamine with 1-naphthyl isothiocyanate as derivatizing agent was carried out in pyridine at 50 degrees C for 1 h. The derivative was accurately analyzed and quantified by using high performance liquid chromatography. The relative standard deviation of glucosamine determined between experimental and real values were less than 2%. The kinetic and strategy of producing glucosamine in a flask culture was investigated to achieve an optimum yield of glucosamine under different conditions including three kinds of fungi, medium, and pH values. The descending ability of producing glucosamine for the three fungi was Aspergillus sp. BCRC31742 > Monascus pilosus BCRC31527 > Rhizopus oligosorus BCRC 31996 under the conditions studied. The experimental result shows that the glucosamine concentration had an optimum value and was 3430 mg/L by using Aspergillus sp. BCRC31742 culture in glucose and peptone (GP) medium, the yield of which was the best amount using wild-type microorganisms in the past. The generation culture of fungi and the pH control played important roles in enhancing the yield of glucosamine. The specific growth rate of the microorganism and the biomass, content, yield, and productivity of glucosamine were calculated as well.

Scale-up of upstream and downstream operations for the production of glucosamine using microbial fermentation.

Glucosamine is used to treat osteoarthritis or as a nutritional supplement. The synthesis, isolation, and purification of glucosamine play a crucial role in its industrial application. This work presents the production of glucosamine from microbial fermentation, and discusses the production problems at both the upstream and downstream operations when the fermentation process is scaled up. The cost evaluation of process design was used to analyze the feasibility of using microbial fermentation for the production of glucosamine. The calculated result shows that the cost of the production of glucosamine should be designed to be approximately between US$200 and 300/kg for the project to be viable.