[Study on lipid production by reusing herb residues of Songling Xuemaikang Capsules]

Songling Xuemaikang Capsules is a Chinese patent medicine mainly made of the Chineses medicine Puerariae Lobatae Radix and leaves of Pinus massoniana. During its production, a large amount of herb extraction residues would be treated as wastes, resulting in resource wasting and serious environmental pollution. In order to solve this problem, we took the hydrolysates of Puerariae Lobatae Radix, P. massoniana leaves, and whole herb residues of Songling Xuemaikang Capsules as the fermentation substrate to explore the ability of Rhodosporidium toruloides to produce microbial lipid. The results showed that the R. toruloides could produce lipid with use of the residues from Songling Xuemaikang Capsules, and the lipid contents reached 33.6%. The lipid products had similar fatty acid composition profiles to those of vegetable oils. Herb residues were converted into fermentation substrates in this study, and were recycled into the production of high value-added compounds to realize the transformation of the wastes, laying the foundation for the sustainable utilization of herb residues.