Physical characteristics, nutrient contents and triterpene compounds of ratoon crops of Centella asiatica at three different stages of maturity

The physical characteristics, nutrient contents and triterpene compounds of Centella asiatica var. Nyonya were investigated at three different stages of maturity: 50, 60 and 70 days after ratooning. Physical characteristics of C. asiatica at each stage of maturity showed no statistical differences (p 0.05) in whole plant length, leaf width, root length and culm length. Moisture content was slightly higher (92%) when harvested at 50 days after ratooning, but the value decreased significantly to 88-89% when harvested at 60 and 70 days. The leaf colour intensity (C* values) was low in young plants but increased significantly as plants grew older. There was significant change in total soluble solids as the maturity period increased. The highest levels of chlorophyll and titratable acidity, and lower level of pH were observed at 60 days of harvest, while ascorbic acid content decreased significantly with advance in maturity. The plant contained significant amount of Na, K, Mg, Fe, Zn, P and Ca. With advance in maturity, the K and Ca levels increased significantly. Different levels of triterpene compounds were observed at different maturity stages. The content of asiatic acid was not significantly different at all stages of maturity. However, the levels of madecassic acid, asiaticoside and madecassoside were significantly different with advance in maturity. These compounds were higher when harvested at 60 days and decreased significantly thereafter. Thus, for the ratoon crop, it is recommended to harvest the plant at 60 days after ratooning since most of the bioactive compounds were observed to be highest at this stage of maturity.