Bioconversion of agro-industrial effluents for polyhydroxyalkanoates production using Bacillus subtilis RS1
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The effectiveness of inexpensive agro-industrial wastes such as sugarcane molasses, paper mill effluent, and dairy effluent for the production of polyhydroxyalkanoates (PHAs) using Bacillus subtilis RS1 was assessed in this study. Laboratory-scale fermentations were carried out with both raw and pre-treated agro-industrial effluents, and maximum PHAs yield was observed in pre-treated effluents. Experimental variables such as pH, inoculum dose, and incubation time were further optimized to maximize PHAs yield, and the optimal conditions were identified as incubation time 48 h; pH 7; and inoculum dose 10% v/v. PHAs yield in pre-treated sugarcane molasses increased to 70.5% under optimal conditions. Fourier transform infrared spectroscopy and gas chromatography–mass spectrometric analysis revealed that the extracted polymer was composed of penta- and hexadecanoic acid methyl esters, a copolymer of PHAs. Results indicated that the pre-treated sugarcane molasses could be used as an inexpensive substrate for the production of PHAs.
KeywordsAgro-industrial effluents Bacillus subtilis RS1 Fermentation Hexadecanoic acid Polyhydroxyalkanoates
This paper was supported by research funds of Chonbuk National University in 2017. The author (SKK) is grateful to the Head and faculties of Department of Environmental Sciences, PSG College of Arts and Science, Coimbatore, Tamil Nadu, India for their valuable support.
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Conflict of interest
The authors declare that they do not have any conflict of interest.
- Desouky SES, Abdel-Rahman MA, Azab MS, Esmael ME (2017) Batch and fed-batch production of polyhydroxyalkanoates from sugarcane molasses by Bacillus flexusAzu-A2. J Innov Pharm Biol Sci 4:55–66Google Scholar
- Gholamveisi N, Azar SM, Moravej R (2018) Bacillus thuringiensis strain NG, a novel isolated strain for production of various polyhydroxyalkanoates. Biol J Microorg 6:13–20Google Scholar
- Khadeejah ONN, Shittu KO, Kabiru AY (2016) Production and characterization of polyhydroxyalkanoate (PHA) using mango seed kernel as an alternative to glucose. Br Biotechnol J 13:1–11Google Scholar
- Khiyami MA, Al-Fadual SM, Bahklia AH (2011) Polyhydroxyalkanoates production via Bacillus plastic composite support (PCS) biofilm and date palm syrup. J Med Plants Res 5:3312–3320Google Scholar
- Kourmentza C, Koutra E, Venetsaneas N, Kornaros M (2017) Integrated biorefinery approach for the valorization of olive mill waste streams towards sustainable biofuels and bio-based products. Microbial Appl 1:211–238Google Scholar
- Law JH, Slepecky RA (1961) Assay of poly-β-hydroxybutyric acid. J Bacteriol 82:33–36Google Scholar
- Munir S, Iqbal S, Jamil N (2015) Polyhydroxyalkanoates (PHA) production using paper mill wastewater as carbon source in comparison with glucose. J Pure Appl Microbiol 9:453–460Google Scholar
- Nehra K, Jaglan A, Shaheen A, Yadav J, Lathwal P (2015) Manpret, production of poly-β-hydroxybutyrate (PHB) by bacteria isolated from rhizospheric soils. Int J Microbial Resour Technol 2:38–48Google Scholar
- Rathika R, Soumiyamithran Saraswathi U, Manonmani S, Kamala Kannan S, Shanthi K (2018) Optimization of polyhydroxyalkanote (PHA) synthesis from Bacillus subtilis RS1. Asian J Microbiol Biotechnol Environ Sci 20:165–171Google Scholar
- Shamala TR, Divyashree MS, Davis R, Kumari KL, Vijayendra SV, Raj B (2009) Production and characterization of bacterial polyhydroxyalkanoate copolymers and evaluation of their blends by Fourier transform infrared spectroscopy and scanning electron microscopy. Indian J Microbiol 49:251–258CrossRefGoogle Scholar