In Vitro Regeneration of Exacum wightianum Arn. (Gentianaceae)- An Endemic Medicinal Plant From The Nilgiris, Western Ghats.

Exacum wightianum Arn. (Gentianaceae) is an endemic medicinal plant from the Nilgiri hills, Western Ghats, Tamil Nadu. Indirect regeneration of E. wightianum was obtained through organogenesis in callus culture. Axial bud explants were found to be best suited for callus induction on MS medium supplemented with BA + NAA (2.0+0.03 mg/L). Multiple shoots originated from callus obtained from the axial buds. were multiplied by subculture on the same medium. Maximum shoot regeneration was obtained on MS medium supplemented with BA with NAA (2.0+0.5 mg/L), and up to 25shoots was observed within 2 weeks.

Evaluation of certain flavonoids of medicinal importance in the wild and micropropagated plants of the endangered medicinal species, Exacum bicolor Roxb.

An efficient micropropagation protocol was developed for the endangered medicinal plant species, Exacum bicolor Roxb. (Gentianaceae) using nodal segments by producing axillary shoots. Quantitative estimation of active compounds of medicinal properties such as luteolin and chlorogenic acid (flavonoids) was made in in vitro regenerated plantlets and compared to that of the wild intact plant by HPLC analysis. The results of the study revealed that the luteolin content was determined to be significantly higher in the wild plant tissues than the plantlets regenerated. However, this trend was reverse for the content of chlorogenic acid.