Abstract:
Coctus speciouses (Koen.) Sm belongs to the family coctacea and is
commonly known as “thebu” in Sinhala. The plant has been found to
possess many pharmacological properties such as antibacterial, antifungal,
anticholineesterase, antioxidant, estrogenic and anti-diabetic. Many
investigations have been reported for chemical and pharmacological
properties of the rhizome of the plants but very limited studies are available
on the leaves of this plant. Therefore, this study was aimed to evaluate
toxicity, analyse proximate composition and determine antioxidant capacity
of the leaves.
Brine Shrimp Lethality Assay was carried out for aqueous extract of the
leaves to determine any cytotoxicy effects and possible pharmacological
effects of the leaves. Cytotoxicy was expressed in Lethality concentration
and the results showed the LC50 of 3170 µgmL-1
for the aqueous extract of
leaves. Standard procedures were followed to determine proximate
composition and the results showed the presence of 67.9% of moisture,
11.9% of total ash, 9.7% of crude fibre, 3.7% of protein, 2.2% of lipid and
4.4% of carbohydrates in the leaves. Antioxidant capacity was determined
using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay and Ferric reducing
activity power (FRAP) assay, and ascorbic acid was used as the standard.
IC50 values obtained in DPPH assay were 730 µg mL-1 and 40 µg mL-1
whereas FRAP values were 23.3 mmol dm-3
and 880.5 mmol dm-3 for the
leaves extract and ascorbic acid respectively. With this study it can be
indicated that leaves extracts can be further evaluated for possible
pharmacological activities, and that no significant calorific value and no
high antioxidant power are associated with the leaves.
