Moringa oleifera Leaf Extract Enhanced Growth, Yield, and Silybin Content While Mitigating Salt-Induced Adverse Effects on the Growth of Silybum marianum

Abstract

Silybin A and B are two major hepatoprotective flavonolignans produced predominantly in Silybum marianum fruits. Similar to other plant secondary metabolites, silybin production is enhanced by biotic or abiotic stresses under the expanse of plant growth and yield. In this study, a novel strategy for enhancing silybin production was investigated by applying a natural plant growth enhancer, moringa leaf extract (MLE), to the S. marianum plants cultivated under salinity abiotic stress. The experiment was conducted using a split-plot design with salinity as the main factor and MLE concentrations as the sub-factor. The individual and combined effects of salinity and MLE on the growth, yield, and silybin content of S. marianum were recorded. The MLE at concentrations of 5 g/L or 10 g/L was applied as foliar spray to S. marianum plants, which were irrigated with either tap water or saline (2000 ppm or 4000 ppm). Our results revealed that 10 g/L MLE effectively enhances the growth, yield, and silybin (A + B) content in S. marianum plants not exposed to salinity stress. On the other hand, for plants that were exposed to 4000 ppm salinity, the application of MLE was able to alleviate the salinity-induced adverse effects on some of the plant growth parameters but did not significantly increase their silybin (A + B) compositions. The current study also indicated that the increase in silybin contents was accompanied by the upregulation of the chalcone synthase 1 and 3 genes, which have been implicated in the synthesis of silybin.

Salicylic Acid Foliar Spray Enhanced Silybum marianum Growth and Yield, as Well as Its Chemical Constituents and Chalcone Synthase Gene Activity

“…[20]. Three CHS genes, namely CHS 1, CHS 2, and CHS 3, have been identified and their expressions were associated with the accumulation of silymarin in S. marianum [21,22]. Salicylic acid, as a plant elicitor, has been shown in multiple studies to elevate the activity of the CHS enzyme, which is involved in flavonoid production [13,23,24].…”

Understanding the physiological and molecular mechanism of salinity stress tolerance in plants

“…Salinity stress enhances the production of ROS that impairs protein and DNA, carbohydrates metabolism, chlorophylls, mitochondria and lipid. Salinity stress exhibits detrimental effects on root activities, which diminishes water and nutrient uptake and accumulation, which may change many physiological traits (Yap et al, 2021;Yue et al, 2022). Previous studies reported that salinity increases the accumulation of toxic ions and ROS production and reduces leaf water potential and relative water contents (Arif et al, 2020;Sarwar et al, 2021).…”

Exogenous Application of Aloe vera Leaf Extract Improves Silybin Content in Silybum marianum L. by Up-Regulating Chalcone Synthase Gene

“…Plant leaf samples were taken 270 days from 10 harvested plants and dried for 48 h at 60 • C. Quantification of nitrogen (N), phosphorus (P), and potassium (K) was performed as previously described [25].…”

“…Four S. marianum plants that were 270 days old had the pigments (chlorophyll a (Chl-a), chlorophyll b (Chl-b), and carotenoid) extracted with 80% acetone from the third bottom fresh leaf [25].…”

“…Three biological replicates of each treatment group's air-dried fruit samples were analyzed by Waters 2690 Alliance HPLC system's (USA) with a Waters 996 photodiode array detector to measure the silybin (A + B) level [25]. Preparations of known concentrations of silybin (A + B) standards and S. marianum methanolic fruit extracts from various treatment groups were performed according to the method described in [25].…”