Chemical constituents and biological activities of bark and flowers of Cassia alata / Syed Abdul Illah Alyahya Syed Abd Kadir

Cassia alata L. (Gelanggang besar), commonly known as “seven golden candlesticks” is a shrub belonging to the family Leguminosae. Medicinal values of all plant parts have been reported. C. alata is a well-known remedy for ringworm and other related parasitical skin diseases such as purities, eczema, itching and scabies. A chemical study was done on the constituents of the dried barks and flowers of C. alata. The crude extracts were obtained by soaking the plant parts in dichloromethane followed by methanol. Isolation work was carried out using extensive chromatographic procedures. Torachrysone and three anthraquinones, known as chrysophanol, physcion, and emodin, along with mixture of sterols were isolated from the barks. Meanwhile, aloe-emodin, and rhein were isolated from flowers. Structures of all compounds were established based on spectral studies using ultraviolet-visible spectroscopy, infrared spectroscopy, one and two dimensional nuclear magnetic resonance spectra, and mass spectrospcopy. In addition structure of torachrysone was also confirmed through crystallographic studies. The various plant parts that are leaf, bark, flower, and pod were also screened for potential biological activities. Bioassays conducted were antioxidant, radical scavenging (DDPH), total phenolic content (TPC), antimicrobial, and antimalaria assay.