Studies on biotransformation of arbutin by 4-hydroxy phenol in hairy root of Polygonum multiflorum Biotransformation of 4-Hydroxybenzen Derivatives by Hairy Root Cultures of Polygonum multiflorum Thunb. Effects of Fungal Elicitors on Cell Growth and Artemisinin Accumulation in Hairy Root Cultures of Artemisia annua Effect of temperature on growth and artemisinin biosynthesis in hairy root cultures of Artemisia annua Study on Hairy-Root Cultures of Fagopyrum cymosum