Four chemical compounds,such as diosmin(Ⅰ),5,8,4′-trihydroxy-6,7-dimethoxyflavone(Ⅱ),5,7,3′-trihydroxy-4′-methoxyflavone(Ⅲ),octacosanoic acid(Ⅳ),are isolated from draff of above-ground part of Mentha haplocalyx Briq.after extracting volatile oil by silica gel and sephadex LH-20 column chromatography methods,and the structures of these compounds are elucidated by 1H-NMR,13C-NMR and ESI-MS.The compounds of Ⅰ,Ⅱand Ⅲ are firstly isolated from draff of M.haplocalyx.
Contents of total flavonoids in above-ground part of Stenoloma chusanum(L.) Ching collected from different production regions were analyzed.The results showed that total flavonoid content in above-ground part of S.chusanum collected from Qiubei of Yunnan Province was the highest,reached to 127.461 mg·g-1,and could keep the high content after transplanted to Nanjing of Jiangsu Province.The total flavonoid content in leaf blade was obviously higher than that in leaf stalk.It is suggested that S.chusanum from Qiubei is an excellent resources and the leaf blade of S.chusanum should be used mainly.