Solasodine

This study aimed for stepwise enhancement of bioactive compound production in ethnomedicinal plant Solanum nigrum through novel approaches of micropropagation, hairy root induction, and treatment of hairy roots with various physical conditions. Polyamines were first-time used for in vitro shoot multiplication of S. nigrum, where highest shoot numbers (55.70 ± 0.64) were observed in Murashige and Skoog's (MS) medium with 0.2 mg/L thiadiazuron + 20 mg/L spermine, whereas maximum root numbers (34.20 ± 0.80) were observed in ½MS medium with 0.5 mg/L indole-3-acetic acid. Pioneer studies of cytogenetical fidelity assessment through inter simple sequence repeat (ISSR) and start codon targeted (SCoT) markers, and chromosome analysis approved genetic uniformity in regenerated plants. Cent percent hairy roots were induced from in vitro S. nigrum leaves (25-30 roots/explant) using Agrobacterium rhizogenes (A4 strain). PCR of transgenes confirmed the transformed nature and absence of bacterial contamination in hairy roots. HPLC studies indicated greater secondary metabolites in hairy roots than in vivo and in vitro plants. Hairy root culture with different culture vessels revealed overall better biomass gain in tightly sealed vessels. However, hairy root cultures treated with red light showed highest biomass accumulation in fresh (2380.13 ± 16.83 mg) and dry (174.66 ± 4.68 mg) weight with maximum solasodine (3.25 ± 0.04 mg/g) and diosgenin (1.03 ± 0.02 mg/g) contents, whereas optimal production of caffeic (3.51 ± 0.05 mg/g), coumaric (2.53 ± 0.06 mg/g), ellagic (0.18 ± 0.02 mg/g), and ferulic (2.17 ± 0.03 mg/g) acid production was found in blue light. These reproducible protocols can be utilized in future bioreactor-mediated mass-culture of hairy roots for commercial-level secondary metabolite production from S. nigrum.

As interest in plant-derived compounds and their application in the pharmaceutical and functional food industries has increased, the rapid detection of chemical toxicity has become increasingly important for developing safe products. High-content screening (HCS) can quantify cellular and organelle morphological changes through image analysis; however, most HCS studies on apoptosis, a key toxicological event, have focused on the expression of apoptosis-related genes or proteins. In this study, we aimed to verify whether apoptosis can be detected solely based on cellular morphological changes. Chang cells were treated with staurosporine (STS), a well-known apoptosis inducer, and the morphological changes in the cells were quantified using HCS assays. The correlation between these HCS morphological descriptors and apoptosis rates measured using flow cytometry was determined. Chang cells were also treated with several plant-derived alkaloids known to induce apoptosis, and the same process was performed. The correlation coefficients, which were used to evaluate the correlation between HCS descriptors and apoptosis rates after STS treatment, ranged from 0.64 to 0.98, with 13 descriptors showing significant correlations. In contrast, the highest correlation coefficients between HCS descriptors and apoptosis rates after treatment with 1 of the 12 alkaloids investigated were determined to be 0.75 (at 10 μg/ml) and 0.49 (at 100 μg/ml). The apoptosis-related morphological changes induced by STS and alkaloids were observed using confocal microscopy. The present study demonstrates that HCS assays can detect apoptosis solely based on cellular morphological changes, providing a potential tool for rapid toxicity screening in early product development.