Lupeol a Potential Growth Regulator: In vitro Physiochemical Response of Physalis peruviana Shoot Tip Culture

Abstract

In vitro techniques for the propagation of plants have emerged as a pivotal tool in facilitating the rapid multiplication of cultivars possessing desirable traits, as well as the generation of robust and pathogen-free plants. Lupeol, a plant triterpenoid has gained attention for its pharmacological properties, yet its impact on plant physiology remains a subject of growing fascination. An in vitro study was conducted to assess the impact of lupeol as a growth regulator on Physalis peruviana (cape gooseberry). The application of lupeol resulted in a substantial enhancement of the morphological characteristics observed in plants cultivated under varying concentrations (1 µM, 5 µM, and 10 µM). Lupeol increased shoot length by 44%, 56%, and 83% and root length by 46%, 100%, and 135% at 1µM, 5µM, and 10 µM, respectively. Fresh and dry weights also enhanced in the presence of lupeol compared to control groups. An alteration in the phytochemical composition of plants accounted for the varying physiological responses. The phenolic and flavonoid content increased with increasing concentration of lupeol. The free radical scavenging activity enhanced when lupeol was applied as compared to positive controls. The total antioxidant response increased by 4.1% at 1 µM, 8.9% at 5 µM, and 54% at 10 µM in shoots and in roots decreased by 1% at 1µM, enhanced by 21% and 50% at 5µM and 10 µM of lupeol. Improvement in total reducing power was observed at different concentrations of lupeol. However, significant variation in antioxidant enzyme activity (SOD and POD) was recorded compared to control. This study shows the significance of lupeol as a promising growth regulator and as a protective agent against oxidative damage in plants.