Production and Characterization of Bioplastic from Halophilic Bacterium Pseudomonas alcaliphila BK-AG13

• Main Author: Alfitro Sianmayo Detant, Archie
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/32281
• Institution: Institut Teknologi Bandung

Several studies have reported that some halophilic bacteria are able to produce bioplastics in the form of polyester compound, such as polyhydroxyalkanoate (PHA) that can be used as a raw material for the production of plastics utensils. In the present study, halophilic bacteria Pseudomonas alcaliphila BK-AG13 and Pseudomonas stutzeri BK-AB12 was screened to examine their potential in producing bioplastics. The screening process was carried out by growing both bacteria on solid agar medium containing nile red. The positive results was showed by Pseudomonas alcaliphila BK-AG13 as indicated by the appearance of orange luminescence colonies under UV irradiation at 312 nm suggesting that bioplastics were produced by this bacterium. Further bioplastics production was carried out by growing Pseudomonas alcaliphila BK-AG13 in the mineral salt medium (MSM) containing 9% (w/v) NaCl and 1% (w/v) maltose as the carbon source and shaking incubated at 37 oC with the aeration rate of 150 rpm. Bioplastics were harvested by lysing the bacterial cell using mixture solvent of CHCl3 and NaOCl with the ratio 1:1, and precipitated with CH3OH. The structure of isolated bioplastics was characterized by Fourier Transform Infrared (FTIR) and the resulted spectrum exhibited high similarity to that of the PHA standard. The FTIR spectrum of bioplastics has the absorption peaks at 3447 cm-1, 2924 cm-1 and 1724 cm-1 that corresponds to the respective vibrations of O–H, CH2 and CH3 from the alkane group, and C?O. Thermal analysis using Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) revealed that the resulted PHA by Pseudomonas alcaliphila BK–AG13 has decomposition and melting temperature at 273 °C and 177,2 °C respectively.