Effects of Sorbitol Osmotic Stress on Biochemical Attributes and Induction of Secondary Metabolites in Rosmarinus officinalis Callus Culture

This research aimed to evaluate the effects of sorbitol-induced osmotic stress on some biochemical properties and secondary phytometabolite production in Rosemary callus cultures.The primary (protein, free amino acids, proline and carbohydrates) and secondary metabolites profiles of callus tissues were measured to evaluate the various metabolic changes in response to the sorbitol levels (30, 60, 90, and 120 g L -1 ) under the influence of thidiazuron (TDZ).The findings highlighted dosedependent increases in osmoprotective solutes, such as proline and carbohydrates, and specific changes in the protein and amino acid profiles under moderate stress.Conditional GC-MS analysis indicated that potent biosynthetic activations of precursor fatty acids/methyl fatty acid esters, silane derivatives, and terpenoids accompanied the higher levels of sorbitol.Both pathways displayed type-specific metabolic reprogramming in response to osmotic pressure.Co-modulation of sorbitol in conjunction with TDZ exhibited a potent boosting effect on the callus growth and further stimulated the production of bioactive compounds.Thus, our findings validated osmotic stress as a feasible in vitro tool for altering primary and secondary metabolism, providing a regulated pathway for increasing the quantity and variety of bioactive natural products from medicinal plants used as herbal medicaments.