Plant material and the preparation of extract The stems of Dendrobium moniliforme were collected from Daman of Makawanpur district in central Nepal. The plant was identified by Dr. Keshav Raj Rajbhandari. A voucher specimen of this plant is deposited in the Tribhuvan University Central Herbarium (TUCH) (voucher number – M02). The collected stems were air-dried and powdered. A Soxhlet extraction was used to prepare plant extracts with solvents of increasing polarity: hexane, chloroform, acetone, ethanol and methanol in the ratio of 1:10 (w/v)[ 32]. The solvents were then evaporated at room temperature to obtain dry extract and the extract was stored at 4 °C.