Optimization of crude rotenone oil extraction from birbira plant (Milletia ferruginea) seed by Soxhlet and maceration methods

The extraction of active compounds from plant materials is one of the most critical processes in the commercial development of natural products for pharmaceutical, herbicide or pesticide production. The focus of this study was extraction of crude rotenone oil (CRO) from Birbira plant (Milletia ferruginea) seed. The extraction was done using maceration anda Soxhlet extractor using organic solvents, such as ethanol, hexane, and chloroform. For the efficient extraction of crude rotenone oil from Birbira plant seed the effect of parameters, such as extraction method, solvent type, extraction time and size of crushed Birbira seed were investigated. Based on the experimental results obtained Soxhlet extraction method was more efficient (41.6% CRO yield) compared to the maceration extraction method (25.1 % CRO yield). The extraction results for both Soxhlet and maceration methods indicated that chloroform is more efficient compared to ethanol and hexane solvents. On the other hand, the effects of crashed seed size and extraction time on the % CRO yield were also investigated. The results showed that medium size (0.1–0.35 mm) for both Soxhlet and maceration extraction was the optimum size leading to the highest % CRO yield compared to fine and coarse ground seed size. The highest % CRO yield was obtained during 4 to 5 h of Soxhlet extraction and 25 to 30 h of maceration extraction method. Therefore, the Soxhlet extraction method is the fastest and efficient method for the extraction of CRO from plant materials. The characterization of Birbira seed powder and CRO was done with FTIR and Rheology test equipment. The FTIR result revealed that CRO is composed of aliphatic, olefin, polyphenol and alcohol functional groups, in which polyphenol functional groups are the most essential flavonoid components available in crude rotenone oil.