Effect of light intensity on chemical composition of Asiatic pennywort ( Centella asiatica L. Urban).

摘要

Centella asiatica L. Urban is a herbaceous plant which is rich in medicinal substances (asiaticoside and madecassoside) and important nutritionals (fiber, protein, calcium and beta-carotene). Asiaticoside, madecassoside and nutritional contents were studied in the leaves of three accessions of C. asiatica, namely 'Nakhon Si Thammarat', 'Ubon Ratchathani' and 'Rayong' grown under the black shade cloth at 0, 50 and 80% shading. The 'Ubon Ratchathani' accession had the highest asiaticoside, protein and calcium content (3.65% (w/w), 18.86 and 1.78 g/100 g dry weight respectively), while the 'Rayong' accession had the highest madecassoside, fiber and beta-carotene content (3.81% (w/w), 11.91 and 18.56 g/100 g dry weight respectively) among the accessions tested. Light intensity affected chemicals and nutritional contents in all accessions. Higher light intensity (0% shading) corresponded to increased asiaticoside and madecassoside contents, but it did not affect fiber content whereas protein, calcium and beta-carotene were decreased. The results from this experiment suggested that light intensity and accessions of C. asiatica affected asiaticoside, madecassoside, protein, calcium and beta-carotene contents.