Tufail Saiqa, Munir Sajida, Jamil Nazia
Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore, Pakistan.
Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore, Pakistan.
Braz J Microbiol. 2017 Oct-Dec;48(4):629-636. doi: 10.1016/j.bjm.2017.02.008. Epub 2017 May 29.
Polyhydroxyalkanoates (PHA) are efficient, renewable and environment friendly polymeric esters. These polymers are synthesized by a variety of microbes under stress conditions. This study was carried out to check the suitability of waste frying oil in comparison to other oils for economical bioplastic production. Six bacterial strains were isolated and identified as Bacillus cereus (KF270349), Klebsiella pneumoniae (KF270350), Bacillus subtilis (KF270351), Brevibacterium halotolerance (KF270352), Pseudomonas aeruginosa (KF270353), and Stenotrophomonas rhizoposid (KF270354) by ribotyping. All strains were PHA producers so were selected for PHA synthesis using four different carbon sources, i.e., waste frying oil, canola oil, diesel and glucose. Extraction of PHA was carried out using sodium hypochlorite method and maximum amount was detected after 72h in all cases. P. aeruginosa led to maximum PHA production after 72h at 37°C and 100rpm using waste frying oil that was 53.2% PHA in comparison with glucose 37.8% and cooking oil 34.4%. B. cereus produced 40% PHA using glucose as carbon source which was high when compared against other strains. A significantly lesser amount of PHA was recorded with diesel as a carbon source for all strains. Sharp Infrared peaks around 1740-1750cm were present in Fourier Transform Infrared spectra that correspond to exact position for PHA. The use of waste oils and production of poly-3hydroxybutyrate-co-3hydroxyvalerate (3HB-co-3HV) by strains used in this study is a good aspect to consider for future prospects as this type of polymer has better properties as compared to PHBs.
聚羟基脂肪酸酯(PHA)是高效、可再生且环境友好的聚酯。这些聚合物由多种微生物在应激条件下合成。本研究旨在检验与其他油相比,废煎炸油用于经济的生物塑料生产的适用性。通过核糖体分型法分离并鉴定出6株细菌菌株,分别为蜡样芽孢杆菌(KF270349)、肺炎克雷伯菌(KF270350)、枯草芽孢杆菌(KF270351)、耐盐短杆菌(KF270352)、铜绿假单胞菌(KF270353)和根际嗜麦芽窄食单胞菌(KF270354)。所有菌株均为PHA生产者,因此选用四种不同碳源,即废煎炸油、菜籽油、柴油和葡萄糖进行PHA合成。采用次氯酸钠法提取PHA,所有情况下均在72小时后检测到最大量。在37°C和100rpm条件下,使用废煎炸油时,铜绿假单胞菌在72小时后导致PHA产量最高,为53.2%,相比之下,葡萄糖为37.8%,食用油为34.4%。蜡样芽孢杆菌以葡萄糖作为碳源时产生40%的PHA,与其他菌株相比这一比例较高。以柴油作为所有菌株的碳源时,记录到的PHA量显著较少。傅里叶变换红外光谱中在1740 - 1750cm附近出现尖锐的红外峰,对应于PHA的精确位置。本研究中所用菌株利用废油生产聚-3-羟基丁酸酯-共-3-羟基戊酸酯(3HB-co-3HV)是未来前景中值得考虑 的一个良好方面,因为这种类型的聚合物与PHB相比具有更好的性能。