Development of a novel solid-state fermentation strategy for the production of poly-3-hydroxybutyrate using polyurethane foams by Bacillus sphaericus NII 0838 (original) (raw)
Related papers
BMC Microbiology, 2022
Background: Polyhydroxybutyrate (PHB) is a biopolymer formed by some microbes in response to excess carbon sources or essential nutrient depletion. PHBs are entirely biodegradable into CO 2 and H 2 O under aerobic and anaerobic conditions. It has several applications in various fields such as medicine, pharmacy, agriculture, and food packaging due to its biocompatibility and nontoxicity nature. Result: In the present study, PHB-producing bacterium was isolated from the Dirout channel at Assiut Governorate. This isolate was characterized phenotypically and genetically as Bacillus cereus SH-02 (OM992297). According to oneway ANOVA test, the maximum PHB content was observed after 72 h of incubation at 35 °C using glucose and peptone as carbon and nitrogen source. Response surface methodology (RSM) was used to study the interactive effects of glucose concentration, peptone concentration, and pH on PHB production. This result proved that all variables have a significant effect on PHB production either independently or in the interaction with each other. The optimized medium conditions with the constraint to maximize PHB content and concentration were 22.315 g/L glucose, and 15.625 g/L peptone at pH 7.048. The maximum PHB content and concentration were 3100.799 mg/L and 28.799% which was close to the actual value (3051 mg/l and 28.7%). The polymer was identified as PHB using FTIR, NMR, and mass spectrometry. FT-IR analysis showed a strong band at 1724 cm − 1 which attributed to the ester group's carbonyl while NMR analysis has different peaks at 169.15, 67.6, 40.77, and 19.75 ppm that were corresponding to carbonyl, methine, methylene, and methyl resonance. Mass spectroscopy exhibited molecular weight for methyl 3-hydroxybutyric acid. Conclusion: PHB-producing strain was identified as Bacillus cereus SH-02 (OM992297). Under optimum conditions from RSM analysis, the maximum PHB content and concentration of this strain can reach (3100.799 mg/L and 28.799%); respectively. FTIR, NMR, and Mass spectrometry were used to confirm the polymer as PHB. Our results demonstrated that optimization using RSM is one of the strategies used for reducing the production cost. RSM can determine the optimal factors to produce the polymer in a better way and in a larger quantity without consuming time.
Media engineering for production of poly-β-hydroxybutyrate by Bacillus firmus NII 0830
This study evaluates biodiesel industry generated crude glycerol as sole carbon source for the production of poly-βhydroxybutyrate (PHB) using Bacillus firmus NII 0830. Pretreatment of crude glycerol from biodiesel industry was tried using strong acids. Biomass yield and PHB accumulation by B. firmus NII 0830 in submerged fermentation was compared using crude as well as pretreated glycerol as sole carbon source. It was observed that crude glycerol from biodiesel industry, without any pretreatment, can be used for PHB production. The organism when grown in mineral salt media containing crude glycerol as carbon source gave a maximum yield of biomass (3 g/l) and PHB (53% of cell dry wt). Response surface methodology (RSM) showed that presence of nitrogen and phosphate in fermentation media favored biomass production but reduced PHB production. Optimized crude glycerol media for maximum PHB accumulation contains ammonium sulphate (4 g/l) and K 2 HPO 4 (0.8 g/l).
Microbial polyhydroxybutyrate production by using cheap raw materials as substrates
Indian Journal of Pharmaceutical and Biological Research
Bioplastic, Polyhydroxybutyrate (PHB) is well known for it’s environmental friendliness and complete decomposition into water and carbon dioxide by microorganisms. The main drawback of PHB commercialization is it’s high production cost which is 10 times higher than that of synthetic plastic. So, the present research work mainly focussed on the fermentative production of PHB by Bacillus amyloliquifaciens and Nocardiopsis potens using low cost raw materials like Molasses, wheat bran, rice bran, ragi bran, jambul seed powder, orange peel and whey as substrates. Bacillus amyloliquifaciens and Nocardiopsis potens gives maximum PHB 16.5 µg/ ml and 26.8 µg/ ml respectively in the medium containing molasses and wheat bran as a substrates. Further the functional groups of extracted PHB were confirmed by Fourier transform infrared spectroscopy.
Optimization of Poly-B-Hydroxybutyrate Production from Bacillus species
2011
The amount of plastic waste increases every year and exact time for its degradation is unknown. Out of a total of 300 isolated strains one strain was selected for PHB production in different conditions like carbon source, nitrogen source and incubation temperature and time. When PHB production conditions were optimized with different carbon and nitrogen sources, the highest PHB production was observed with raffinose and peptone. Regarding incubation time and temperature and pH, optimum PHB production conditions were 72h, 30°C and 7.0, respectively. The isolate was characterised biochemically as Bacillus species. The present study provide the useful data about the optimized conditions for PHB production by Bacillus species that can be utilized for industrial production of PHB, a fast emerging alternative of non biodegradable plastics.
Annals of Microbiology, 2013
A newly isolated poly(3-hydroxybutyrate) [P(3HB)] producing strain, ST1C, was identified as Bacillus aryabhattai based on its morphological, biochemical and molecular characteristics. It synthesized and accumulated relatively high amounts of P(3HB). The aim of this work was to establish if it could convert an inexpensive liquid waste product from the production of biodiesel, biodiesel liquid waste (BLW), to P(3HB). Using a mineral salt medium (MSM) containing 2.0 % (v/v) glycerol present in the BLW and both normal batch and a draw and fill culture method, B. aryabhattai ST1C produced a maximum P(3HB) content and biomass concentration of 72.31 % dry cell weight (DCW) and 7.24 g/L, respectively, over a 24 h cultivation period in the draw and fill cultivation method. From 24 h to the end of cultivation at 72 h both the P(3HB) content and the biomass concentrations continuously reduced. Concentrations of glycerol in the BLW in this MSM above 3.0 % (v/v) or from pure glycerol (PG) or with an added NaCl concentration of greater than 3.0 % significantly reduced both the maximum P(3HB) content and the biomass concentrations.
Brazilian Archives of Biology and Technology, 2009
The aim of this work was to study the production of polyhydroxybutyrate (PHB) using agro-industrial residues as the carbon source. Seven substrates, viz., wheat bran, potato starch, sesame oil cake, groundnut oil cake, cassava powder, jackfruit seed powder and corn flour were hydrolyzed using commercial enzymes and the hydrolyzates assessed for selecting the best substrate for PHB production. Jackfruit seed powder gave the maximum production of PHB under submerged fermentation using Bacillus sphaericus (19%) at the initial pH of 7.5.
Biomacromolecules, 2009
P(3HB), is one of the most well studied polyhydroxyalkanoates. It is biodegradable, biocompatible, exhibits thermoplastic properties and can be produced from renewable carbon sources. The commercial exploitation of P(3HB) has been mainly held back by its high production costs. Hence, a lot of research is required to optimize P(3HB) fermentation conditions. In this study we have focused on the effects of impeller speed and pH on P(3HB) production in Bacillus cereus SPV. Four different impeller speeds, 50, 125, 250, and 500 rpm, were used. The highest amount of P(3HB) accumulation was achieved using 125 rpm impeller speed (34% dcw) and this was attributed to optimal cell growth rate. Also, pH-stat fermentations were carried out at pH 3.0, 6.8, and 10. This study confirmed that lack of P(3HB) degradation during unbuffered Bacillus fermentations is due to the low pH conditions. This observation is crucial for the industrial exploitation of the genus Bacillus for the production of P(3HB).
Microbial Biotechnology
Poly-(3-hydroxybutyrate) [P(3HB)] is a polyester synthesized as a carbon and energy reserve material by a wide number of bacteria. This polymer is characterized by its thermo-plastic properties similar to plastics derived from petrochemical industry, such as polyethylene and polypropylene. Furthermore, P(3HB) is an inert, biocompatible and biodegradable material which has been proposed for several uses in medical and biomedical areas. Currently, only few bacterial species such as Cupriavidus necator, Azohydromonas lata and recombinant Escherichia coli have been successfully used for P(3HB) production at industrial level. Nevertheless, in recent years, several fermentation strategies using other microbial models such as Azotobacter vinelandii, A. chroococcum, as well as some methane-utilizing species, have been developed in order to improve the P(3HB) production and also its mean molecular weight.
Poly-β-hydroxybutyrate (PHB) is the intracellular lipid reserve accumulated by many bacteria. The most potent terrestrial bacterium Bacillus cereus SE-1 showed more PHB accumulating cells (22.1 and 40% after 48 and 72 h) than that of the marine Bacillus sp. CS-605 (5 and 33% after 48 and 72 h). Both the isolates harbored phbB gene and the characteristics C=O peak was observed in the extracted PHB by Fourier transformed infrared spectroscopy analysis. Maltose was found to be the most suitable carbon source for the accumulation of PHB in B. cereus SE-1. The extracted PHB sample from B. cereus SE-1 was blended with a thermoplastic starch (TS) and an increased thermoplasticity and decreased crystallinity were observed after blending in comparison to the standard PHB. The melting temperature (T m ), melting enthalpy (ΔHf), and crystallinity (X c ) of the blended PHB sample were found to be 109.4°C, 64.58 J/g, and 44.23%, respectively.