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We investigated the use of bacterial cells isolated from paddy crab for the extraction of oil from Jatropha seed kernels in aqueous media while simultaneously preserving the protein structures of this protein-rich endosperm. A bacterial strain—which was marked as MB4 and identified by means of 16S rDNA sequencing and physiological characterization as either Bacillus pumilus or Bacillus altitudinis—enhanced the extraction yield of Jatropha oil. The incubation of an MB4 starter culture with preheated kernel slurry in aqueous media with the initial pH of 5.5 at 37 °C for 6 h liberated 73% w/w of the Jatropha oil. Since MB4 produces xylanases, it is suggested that strain MB4 facilitates oil liberation via degradation of hemicelluloses which form the oil-containing cell wall structure of the kernel. After MB4 assisted oil extraction, SDS-PAGE analysis showed that the majority of Jatropha proteins were preserved in the solid phase of the extraction residues. The advantages offered by this process are: protein in the residue can be further processed for other applications, no purified enzyme preparation is needed, and the resulting oil can be used for biodiesel production.

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Global consumption of polyethylene terephthalate (PET) increases each year, resulting in considerable buildup of plastic waste in the environment. A whole cell biocatalyst (WBC) with LC-cutinase bound to its outer membrane had been constructed to hydrolyze PET (optimum temperature 55°C). The aim of this study was to improve WBC viability at 55°C by inserting Ef-TU gene from sugarcane into WCB cells, with the hope of improving its hydrolytic activity. Escherichia coli BL21(DE3) was co-transformed with two plasmids, the first contained Lpp-OmpA-LC-cutinase fused gene and the second contained Ef-TU gene. Cells transformed with only the first plasmid were used as control. The cells were grown at 37°C and 55°C and viability was analyzed by total plate count. LC-cutinase activity was measured using pNPB as substrate and its capability to hydrolyze PET was observed by scanning electron microscopy. The presence of Ef-TU improved WCB viability at 55°C after 90 minutes incubation and LC-cutinase activity remained stable after 72 hours incubation at 55°C. LC-cutinase activity of WCB with Ef-TU was consistently higher than without EF-TU. Scanning electron micrograph of PET sheets incubated with WBC cultures with Ef-TU showed larger pockets than without EF-TU.