Study of The Fermentation Conditions of the Bacillus Cereus Strain ARY73 to Produce Polyhydroxyalkanoate from Glucose

Abstract

Polyhydroxyalkanoates (PHAs) have gained much attention as biodegradable polymers, many efforts are being made to minimize the cost of PHAs by finding cheap carbon source depending on the type of microorganism and fermentation conditions. The aims of this study were to evaluate the effects of different glucose concentrations and other important conditions on the PHA production by Bacillus cereus isolated from soil. Polyhydroxyalkanoates PHAs accumulated by soil microorganisms were examined by screening the isolated bacteria using Sudan B Black and Nile Blue staining process. A Gram positive strain was identified using the 16s rRNA gene, deposited in the NCBI GenBank sequence database. Different growth conditions (favorite glucose concentrations 1-8 % (w/v), temperatures and pH) were tested and the growth parameters (sugar consumption, cell counting and Cell Dry Weight CDW) were studied. The extracted polymers were analyzed and characterized using an FTIR spectrophotometer followed by a GC-MS analysis. The pure bacterial strain isolated from soil was deposited in the NCBI GenBank database B. cereus strain ARY73, which showed significant black colored granules (or dark blue) using Sudan B Black stain, it also showed positive to Nile blue A as a high indicator stain for PHA accumulation. B. cereus ARY73 showed high production of PHA using (w/v): 2% glucose and 1% nitrogen source at 35 °C and pH7 yields 79% per Cell Dry Weight and 96 h of incubation. The extracted polymers were analyzed and characterized using an FTIR spectrophotometer confirming the PHA structure. The FTIR spectrophotometer, followed by a GC-MS analysis indicated the Scl-co-mcl PHA structure. This research demonstrates that the isolated strain B. cereus ARY73 was a good candidate for PHA production with a better quality for use in biomedical and other applications. The use of biopolymer in soil, enhanced the accumulation of the microorganisms (such as bacteria) capable of degrading biopolymer or biodegradation by-products yields by other species which were isolated in this study and demonstrated their efficiency in producing biopolymers.

Production and optimization of bioplastic (Polyhydroxybutyrate) from Bacillus cereus strain SH-02 using response surface methodology

“…Bacillus cereus SH-02 (OM992297) produced the maximum PHB amount at 35 °C. This result correlates with the results of Yasin [22] who obtained the highest PHA production using 2% glucose and 1% nitrogen source at 35 °C and pH 7 from Bacillus cereus ARY73. Glucose and peptone were found to be the best carbon and nitrogen source for maximum PHB production.…”

Production of Polyhydroxyalkanoate by Bacillus thuringiensis Isolated from Agricultural Soils of Cascas-Peru

“…On the other hand, it was found that the SP7-1 strain accumulated 19% of PHA in dry weight of the cell biomass. This result last is found in the range reported by Baikar and coauthors [37] between 14-23% of three isolated cultures of from a biogas plant; however, have been found in other studies high values of up to 79% with other species of Bacillus cereus [38]. In addition, there have been reported Bacillus thuringiensis strains that can accumulate up to 58.5 % in glucose (20 g/L) due to nitrogen deficiency [39].…”

Spatiotemporal based response for methylene blue removal using surface modified calcium carbonate microspheres coated with Bacillus sp.

“…On the other hand, ref. 38 showed that higher growth and maximum PHA production was detected in the glucose medium 40 g L −1 . Our results show that glucose contribution was the least of the three tested factors as seen from the factorial design.…”