Assessment of antimicrobial and antioxidant activities of <i>Dendrocnide sinuata </i>(Blume) Chew leaves–A medicinal plant used by ethnic communities of North East India

17-21 Traditional medicine plays an important role in the primary health care in India. Dendrocnide sinuata (Blume) Chew has been used as medicine for curing diseases by different tribal communities of North East India. An ethno-medicinal study was done among few tribal communities of this region through questionnaires in consultations with the tribal practitioners and has resulted in the documentation of various uses of the plant for curing diverse form of ailments. Further, in vitro study was carried out to investigate its antimicrobial and antioxidant properties from the leaf extract of the plant. The methanol and aqueous extracts of leaves were tested for their antimicrobial activity against three Gram-positive bacteria, three Gram-negative bacteria, one yeast species using Agar diffusion method and for their antioxidant activity using scavenging activity of DPPH (1,1-diphenyl-2-picrylhydrozyl) radical method. Antimicrobial activity was observed against Gram-negative bacteria only. The highest antimicrobial activity was exhibited by the 75 and 100% methanolic extracts but no extract showed any antifungal activity against Candida albicans used in the study. The methanolic leaf extracts of 75 µg/ml and 100µg/ml concentrations also exhibited high free radical scavenging activity. The phytochemical screening demonstrated the presence of different types of compounds like terpenoids, tannins, flavonoids and others, which could be responsible for the antimicrobial and antioxidant activities. </smarttagtype