Budiman Pretty Mori, Wu Ta Yeong, Ramanan Ramakrishnan Nagasundara, Md Jahim Jamaliah
Chemical Engineering Discipline, School of Engineering, Monash University, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor Darul Ehsan, Malaysia.
Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor Darul Ehsan, Malaysia.
Environ Sci Pollut Res Int. 2017 Jul;24(19):15870-15881. doi: 10.1007/s11356-017-8807-x. Epub 2017 Apr 13.
One-time ultrasonication pre-treatment of Rhodobacter sphaeroides was evaluated for improving biohydrogen production via photofermentation. Batch experiments were performed by varying ultrasonication amplitude (15, 30, and 45%) and duration (5, 10, and 15 min) using combined effluents from palm oil as well as pulp and paper mill as a single substrate. Experimental data showed that ultrasonication at amplitude 30% for 10 min (256.33 J/mL) achieved the highest biohydrogen yield of 9.982 mL H/mL with 5.125% of light efficiency. A maximum COD removal of 44.7% was also obtained. However, when higher ultrasonication energy inputs (>256.33 J/mL) were transmitted to the cells, biohydrogen production did not improve further. In fact, 20.6% decrease of biohydrogen yield (as compared to the highest biohydrogen yield) was observed using the most intense ultrasonicated inoculum (472.59 J/mL). Field emission scanning electron microscope images revealed the occurrence of cell damages and biomass losses if ultrasonication at 472.59 J/mL was used. The present results suggested that moderate ultrasonication pre-treatment was an effective technique to improve biohydrogen production performances of R. sphaeroides.
对球形红细菌进行一次性超声预处理，以评估其对通过光发酵提高生物制氢的效果。使用棕榈油以及纸浆和造纸厂的混合废水作为单一底物，通过改变超声振幅（15%、30%和45%）和持续时间（5分钟、10分钟和15分钟）进行分批实验。实验数据表明，在30%振幅下超声处理10分钟（256.33焦/毫升）时，生物制氢产率最高，为9.982毫升氢气/毫升，光效率为5.125%。同时，化学需氧量（COD）的最大去除率也达到了44.7%。然而，当向细胞传递更高的超声能量输入（>256.33焦/毫升）时，生物制氢并没有进一步提高。事实上，使用强度最大的超声处理接种物（472.59焦/毫升）时，生物制氢产率下降了20.6%（与最高生物制氢产率相比）。场发射扫描电子显微镜图像显示，如果使用472.59焦/毫升的超声处理，会出现细胞损伤和生物质损失。目前的结果表明，适度的超声预处理是提高球形红细菌生物制氢性能的有效技术。
