Balanites (Balanites aegyptiaca L.), also known as desert palm or heglig, is a critically endangered plant and an endemic agroforestry species in Egypt. It is a member of the Balanitaceae family. Balanites aegyptiaca is a species with a wide range of applications in different countries, including medicinal, charcoal, pesticides, and forage, and in vitro callus production is critical for many applications in both basic and industrial research on this species. Plant tissue culture has numerous advantages for the potential synthesis of bioactive plant metabolites.

Culturing leaves on full strength Murashige and Skoog (MS) medium supplemented with 2.50 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) resulted in a green compact callus. Callus cultures were grown on MS media with various concentrations of 2, 4-D (1.00, 1.50, 2.00, 2.50, and 3.00 mg/L), as well as the cytokinins 6-benzylaminopurine (BAP) and Kinetin (6-furfurylaminopurine) (Kin) at 0.5 mg/L. The maximum fresh weight of callus was obtained using MS medium containing 2.5 mg/L 2,4-D plus 0.5 mg/L BAP, as well as the highest percentage of increase in fresh weight, which was 300 %.

Salicylic acid and chitosan were used as elicitors for secondary metabolites accumulation in callus culture. Chitosan (40 mg/L) increased quercetin 2.6 folds and kaempferol 8.5 folds rise after 45 days of culture. However salicylic acid enhanced the maximum accumulation of total phenols in (0.2 mg/L). The dramatic decrease in accumulation of coumarin may give rise to the consuming of such precursor in flavonoids biosynthetic pathways. Chitosan as an elicitor enhanced the biosynthesis of fucose sugar in (40 and 80 mg/L) and this may have antioxidant and anticancer properties.

The usefulness of salicylic acid and chitosan as elicitors for increasing in vitro production of secondary metabolites in plants is demonstrated in this work. These findings could point to the important role of plant callus culture which would play a potential role in the future of the phytopharmaceutical sector.