Effect of support materials on antibiotic MSW2000 production by immobilized Streptomyces violatus

Abstract

The production of an antibiotic by free and immobilized cells of Streptomyces violatus through entrapment or adsorption on different materials was investigated. S. violatus entrapped in Ca-alginate beads gave low antibiotic activity compared to the free cell or adsorbed cell, while the adsorption of S. violatus on sponge cubes yielded the highest antibiotic concentration after 4 days of incubation in static cultures. A starch concentration of 10 g/L was optimum for the production of the antibiotic by adsorbed cells. The weight and size of the sponge cubes used for immobilization influenced production of the antibiotic and the optimum weight and size of the sponge were 0.8 g and 1.0 cm(3), respectively, yielding a maximum antibiotic production of 280 mg/ml. Maximum antibiotic production was obtained at an initial pH value of 7.5 and in an inoculum size of 3 ml (spore suspension) per 50 ml. The production of the antibiotic in a fixed-bed bioreactor reached a maximum value after 2 days of incubation at a circulation rate of 30 ml/h. The immobilized cells in the bioreactor were reused seven successive times over a period of 14 days.

Production, Purification, and Characterization of Bioactive Metabolites Produced From Rare Actinobacteria Pseudonocardia Alni

“…Thus, standing condition is more suitable for antibiotic production. These results were in agreement with El-Naggar et al [23] who reported the highest production of antimicrobial substances by S. violates occurred after four days of incubation period under static conditions. Miyoshi et al [24] who observed an increase in agitation led to the loss of antibiotic production, but a high level of production obtained at static condition.…”

“…The effect of pH is ionizing the nutrients to facilitate uptake by microorganisms and to stimulate production pathways of antibiotics. Many researchers documented that the pH value of antibiotic production medium has different influences to guide the production toward positive or negative directions depending on the microorganism categories; in other words, any microorganism such as Streptomyces aburaviensis, Streptomyces violates, and Pseudonocardia needs optimal pH for highest antibiotic production, which had the maximum antibiotic yield at pH of 9, 7.5, and 7, respectively [5,6,[17][18][19][20][21][22][23].…”

“…Many researchers reported that most of the actinobacterial species have the ability to produce maximum level of antibiotic productions at 30°C because these microorganisms were having an optimal growth at the same temperature similar to Streptomyces, S. violates, and also these organisms appeared to have poor growth and low level of antibiotic production at higher or lower optimum temperatures [5,23].…”

Optimization of Culture Conditions for Production of Bioactive Metabolites by <i>Streptomyces</i> spp. Isolated from Soil

“…Optimal production has been achieved by cultivating organisms in media containing slowly utilized nutrient sources [22] [23]. Starch has been found to be the best carbon source for antibiotic production by several researchers [24] [25].…”

Optimization Production Conditions of Antibacterial Metabolite From Streptomyces Sp.

“…The cultural factor optimization plays a remarkable role in the productivity and economics of the essential process [13][14][15][16][17][18][19]. Hence, our study was aimed to the isolation of Streptomyces sp.…”