Bacillus subtilis HB1310 from Thin-Shelled Walnut and its Use for Lipid Production

Biodiesel processing from microbial lipids using cheap plant feedstock has gained attention. Endophytic bacteria from oleaginous plants are possibly capable of accumulating lipids. However, few studies have been reported of endophytic bacteria isolation and their lipid production using plant extracts.

Liming Xia from Zhejiang University, and a team of researchers isolated a new endophyte Bacillus subtilis HB1310 from the thin-shelled walnut. This strain effectively accumulated lipids using cotton stalk extract as substrate. Batch fermentation was conducted in a bioreactor with optimum conditions and obtained a maximum lipid productivity of 2.3 g/L, lipid content of 39.8% (w/w), and cell dry weight (CDW) of 5.7 g/L, after 48 h. The fatty acid profile of the produced lipids indicates that this strain may be suitable for biodiesel production.

The results showed that the new endophytic bacterium is capable of producing high amounts of lipid rapidly using cotton stalk extract. It products are also suitable for biodiesel production.