Mentha oil futures prices weakened by Rs 5.40 to Rs 1,121 per kg today, as speculators booked profits amid fall in spot market demand.
Increased arrivals at spot market from the producing belts of Uttar Pradesh also influenced trading sentiments.
At the Multi Commodity Exchange counter, mentha oil for delivery in October fell by Rs 5.40, or 0.48 per cent, to Rs 121.80 per kg, with a business turnover of just one lot.
Similarly, the oil for delivery in November traded lower by Rs 1.90, or 0.17 per cent, to Rs 1,145.00 per kg, clocking a trade volume of just one lot.
Market analysts said profit taking by speculators, driven by fall in demand at spot markets, mainly led to a decline in mentha futures prices.
They said reduced offtake from pharmaceutical units was another weakening factor for the oil.