Synthesis and characterization of polyhydroxyalkanoates from soil bacterium Bacillus sp. PhNs9

Abstract

Background: Synthetic plastic pollution has increased tremendously over the past few decades. Supplanting synthetic plastics with a biodegradable alternative could save the biosphere from the drastic effects of plastic pollution. Polyhydroxyalkanoates (PHA) have been identified with the potential to become a feasible option.Results: A bacterial strain isolated from pavement soil was investigated for its PHA production ability. The isolated strain was found to be non-virulent, and susceptible to various antibiotics, especially cefalexin, tetracycline, chloramphenicol, norfloxacin and ofloxacin. The carbohydrate utilization profile revealed that isolated bacteria can utilize different carbohydrates with a variable rate of consumption. The 16S rRNA identification revealed that the strain was related to the Bacillus genus. The produced PHA was predicted to be polyhydroxybutyrate as suggested by differential scanning calorimetry and NMR, Fourier transform infrared and Raman spectroscopies. Moreover, the hydrophobic nature of the PHA produced was confirmed by contact angle measurement. The growth, production and substrate utilization kinetics revealed the specific growth rate of Bacillus sp. PhNs9 was 0.07 h −1 , specific biomass productivity was 0.06 g L −1 h −1 and specific PHA productivity was 0.05 g L −1 h −1 . The yield of PHA from biomass was found to be 0.67 g per gram of biomass.Conclusions: The yield of PHA from the isolated strain was found to be higher than that of most earlier reports. Hence the findings of this study could catalyze the progress to completely move away from the use of synthetic plastics and replace them with an economical and sustainable solution.

Ecotoxicological Impact of Bioplastics Biodegradation: A Comprehensive Review

“…Brdlík et al ( 2021) observed a 16% weight loss in PLA under composting conditions over 60 days [27]. This aligns with the findings of Karamanlioglu et al (2017), who reported a 20% weight reduction in PLA over 20 months in soil [28]. Notably, controlled composting with bacterial treatment resulted in the complete degradation of PLA within 60 days as indicated in (Figure 2) [29].…”

Synthesis and Biodegradation Test of a New Polyether Polyurethane Foam Produced from PEG 400, L-Lysine Ethyl Ester Diisocyanate (L-LDI) and Bis-hydroxymethyl Furan (BHMF)

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In Focus: Application of resilient environmental technologies for waste utilization and resource recovery

“…Simple and efficient production techniques of bioplastics will help to move away from the use of synthetic plastics and assist in reducing plastic pollution in the environment. The second article by Patil et al 5 investigates the synthesis and characterization of PHAs from soil bacterium Bacillus sp. PhNs9.…”