ANTILIPASE ACTIVITY AND CHEMICAL CONSTITUENTS OFSolanum aculeatissimum Jacq. FRUITS

Abstract

The nineteen Thai medicinal plants were investigated for anti-lipase activity. These plants were extracted with methanol and DI water. The methanolic and aqueous crude extracts of these plants were evaluated on anti-lipase activity. It was found that the methanolic extract of fruits of Solanum aculeatissimum showed the strongest inhibition of lipase activity. Thus, methanolic crude extract of S. aculeatissimum fruits were extracted by liquid-liquid extraction to obtain hexane, ethyl acetate, n-butanol and aqueous crude extracts. The hexane and n-butanol crude extracts of S. aculeatissimum fruits showed strong lipase inhibitory activity at a concentration of 25 mg/mL with percent inhibition as 81.88 ± 0.98% and 80.74 ± 1.39%, respectively. The ethyl acetate crude extract of S. aculeatissimum fruits showed moderate lipase inhibitory activity at a concentration of 25 mg/mL with percent inhibition as 60.41 ± 7.36%. Aqueous crude extract showed weak activity at a concentration of 25 mg/mL with percent inhibition as 22.12 ± 1.29%. The hexane and n-butanol crude extracts were further isolated to obtain six compounds. The hexane crude extract was isolated to give a mixture of fatty acids (compound 209) and steroidal mixture (compound 210). The n-butanol crude extract was isolated to give a mixture of steroidal glycosides (compound 211), solasodine (compound 212), solasonine (compound 213) and alpha-solanine (compound 214). Compounds 209 - 212 showed weak lipase inhibitory activity with IC50 values of 523.30 ± 0.91, 675.58 ± 1.29, 565.06 ± 1.27 µg/mL and 404.26 ± 1.39 µM, respectively. Compounds 213 and 214 exhibited moderate lipase inhibitory activity with IC50 values of 198.75 ± 0.96 and 223.43 ± 0.16 µM, respectively. Orlistat showed lipase inhibitory activity with IC50 value of 0.27 ± 0.07 µM. Compounds 209 - 214 exhibited in ranging of weak to moderate lipase inhibitory activity whereas hexane and n-butanol crude extracts showed strong lipase inhibitory. These results suggested that the chemical constituents of S. aculeatissimum fruits should be further investigated for the active components responsible for anti-lipase activity.