Tulipalin A (α-methylene-γ-butyrolactone) (2-Methylenebutyrolactone) which has some phytotoxicity is a natural compound extracted from Tulipa gesneriana.

Tulipalin A 引起的植物毒性表现为长期的过敏性接触性皮炎，这一点在暴露于百合及其栽培品种的花卉工作者中有文献记载[1]。THP-1细胞对Tulipalin A的处理显示出强大的鲁棒性，因为只有五种蛋白质发生了变化。相比之下，Jurkat T 细胞内66种蛋白质的数量增加，而6种蛋白质的数量减少[2]。

The influence of TUPA on cell viability was measured using the MTT assay. Cells were seeded in flat bottom 96-well plates at a density of 4 x 10^5 cells/ml. Afterward, Jurkat cells were exposed to TUPA in concentrations ranging from 10 to 82 μM. THP-1 cells (4 x 10^5 cells / ml) were exposed to concentrations ranging from 20 to 163 μM. After incubation for 72 h under humidified conditions (5 % CO2, 37 °C), 10 μl of MTT (5 mg/ml) per well were added and cells were further incubated for 3 h. Subsequently, 200 μl DMSO was added for cell lysis and formazan solubilization following incubation of the plates for 15 min while shaking. Afterward, absorbance was recorded at 550 nm and 620 nm using a microplate reader. In each plate, cells remained either untreated (negative control) or were exposed to Etoposide (2.5 μM) as a positive control. Using linear regression of the cell viability as a function of the compound concentrations, the concentrations leading to viability decreases of 10 % and 50 %, respectively, were calculated [2].