龙胆
根含裂环烯醚萜甙类苦味成份:龙胆苦甙(gentiopicroside),当药苦甙(swertiamarin),当药甙(sweroside),苦龙胆酯甙(amarogentin),痕量苦当药酯甙(amaroswerin);苦甙总含量可高达7.33%,而龙胆苦甙含量可达6.34%。生物碱:龙胆碱即秦艽碱甲(gentianine0.05%,龙胆黄碱(gentioflavine)。
条叶龙胆
根含裂环烯醚萜甙类苦味成份:龙胆苦甙,当药苦甙,当药甙,苦龙胆酯甙,痕量苦当药酯甙;苦甙总含量可达4.35%,而龙胆苦甙含量为4.15%。
三花龙胆
根含裂环烯酸萜类成份:龙胆苦甙,当药苦甙,当药甙,痕量苦当药酯甙;苦甙总含量为3.95%,而龙胆苦甙含量为3.66%。还含三花龙胆甙(TCMLIBifloroside)。
滇龙胆
根含裂环烯醚萜甙类苦味成份:龙服苦甙,当药苦甙,当药甙,痕量苦龙胆酯甙,痕量苦当药酯甙;苦甙总含量5.10%,龙胆苦甙含量5.01%。地上部分含龙胆碱,秦艽碱乙(gentianidine),秦艽碱丙(gentianal),β-谷甾醇(β-sitosterol)。