Pharmacological Screening of Four Medicinally Important Plants: Curcuma zedoaria, Nymphoides indica, Drynaria quercifolia and Rhynchostylis retusa

Abstract

In this study, four species of medicinally important plants namely Curcuma zedoaria (Zingiberaceae), Nymphoides indica (Menyanthaceae), Drynaria quercifolia (Polypodiaceae) and Rhynchostylis retusa (Orchidaceae), having traditional claims for the treatment of various diseases were investigated for their pharmacological properties. All of the plant extracts were evaluated for antimicrobial activity by using disk diffusion method and agar well dilution method. Among the plant extracts, only Nymphoides indica crude extract and its Ethyl acetate fraction showed promising antimicrobial activity against a number of bacterial and fungi strains, which are known to be common pathogens to human. The highest zone diameter was 15 mm against Streptococcus pyogens and Staphylococcus saprophyticus at a dose of 800 μg for the crude extract of Nymphoides indica whereas the ethyl acetate fraction of Nymphoides indica showed highest inhibition zone diameter of 10 mm on Bacillus cereus at a dose of 200 μg. The VLC fractions of Curcuma zedoaria was investigated for analgesic activity by using acetic acid induced writhing method. All the fractions except fraction 3 (ethyl acetate) showed significant reduction (p<0.05, and p<0.01) of writhing method induced by acetic acid at a dose of 200 mg/kg. Among all the fractions, fraction 2 (DCM) showed highest percentage inhibition of 45.52% reduction in writhing at a dose of 200 mg/kg., which was greater than the inhibition shown by the reference drug Diclofenac (39.74% at a dose of 10 mg/kg). The VLC fractions of Nymphoides indica was investigated for anti-inflammatory activity by using Carrageenan induced paw edema method. Fraction 3 (ethyl acetate) of the plant showed better activity than the reference drug Indomethacin (10 mg/kg) at a dose of 400 mg/kg.