PURIFICATION OF AZADIRACHTIN VIA SILICA GEL COLUMN CHROMATOGRAPHY

Abstract

Separation efficiency for purifying azadirachtin from the mixture of neem limonoids was investigated by silica gel column chromatography in this study. The reliability of this method was confirmed by using limonoid powders A and B with initial azadirachtin purities of 18% and 7%, respectively. The silica gel chromatography employed in this study was capable of increasing the azadirachtin purity up to 4-fold with an azadirachtin recovery of approximately 50%. Powders with an azadirachtin content of approximately 50% and 28% were produced from limonoid powders A and B, respectively. Meanwhile, low separation efficiency was produced when starting material contained 50% azadirachtin. Therefore, this method is effective in increasing azadirachtin purity using starting materials with azadirachtin content below 20%.

Keywords:

• azadirachtin
• column chromatography
• limonoids
• neem
• separation efficiency
• silica gel

ABBREVIATION:

• EtOAc
• ethyl acetate

ACKNOWLEDGMENTS

This work was supported by a project (NSC 98-2221-E-011-046-MY3) from the National Science Council of Taiwan.

Notes

^a Mean ± SD, data replication at least in duplicate.

^b Ratio of silica gel to sample of 50.

^c Ratio of silica gel to sample of 100.