Enhancing Jatropha oil extraction yield from the kernels assisted by a xylan-degrading bacterium to preserve protein structure

Abstract

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.

Rapid detoxification of Jatropha curcas cake by fermentation with a combination of three microbial strains and characterization of their metabolic profiles

“…Jatropha curcas L. is widely cultivated in semi‐tropical and tropical regions for its bioenergy use. Under the pressures of energy shortage, environmental pollution and agricultural sustainability, Jatropha biodiesel, a clean and renewable new energy source (Marasabessy et al, 2011), has become increasingly important and has been extensively cultivated around the world (Juan et al, 2011; Ndimba et al, 2013). Jatropha curcas L. cake (JCC) is a by‐product of the biodiesel industry and is attracting growing ecological concern because of its large quantity of production and improper application, i.e., direct combustion or discarded as agricultural wastes, leading to environmental pollution (Langrand et al, 2015; Pimentel et al, 2012).…”

Optimisation of solid liquid extraction of jatropha oil using petroleum ether

“…Unlike its competitors, aqueous enzymatic extraction is eco‐friendly, does not require extensive energy for solvent separation and has less fire/explosion risks. Several researchers have exploited various enzymes to extract jatropha oil . Enzymatic extraction has also been combined with ultrasound and three‐phase partitioning to enhance oil recovery.…”