| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Frangula purshiana | Plant | -- | -- | * | |
| Aloe vera | Leaf | -- | -- | Mary, N. Y., Christensen, B. V., Beal, J. L. 1956. A Paper Chromatographic Study of Aloe, Aloin and Cascara sagrada. J. Amer. Pharm. Ass. Sci. Ed., 45: 229-232. | |
| Aloe vera | Juice | -- | -- | Waller, G. R., Mangiafico, S., Ritchey, C. R. 1978. A Chemical Investigation of Aloe barbadensis. Proc. Okla. Acad. Sci. 58: 69-. | |
| Bryonia alba | Root | -- | -- | * | |
| Rumex hymenosepalus | Plant | -- | 12000.0 | CRC Handbook of Medicinal Herbs and/or CRC Handbook of Proximate Analyses | |
| Tabebuia heptaphylla | Bark | -- | -- | * | |
| Ruscus aculeatus | Plant | -- | -- | Lawrence Review of Natural Products, Sep-91. | |
| Frangula purshiana | Bark | -- | -- | * | |
| Ruscus aculeatus | Root | -- | -- | * | |
| Rhamnus cathartica | Stem Bark | -- | 10.0 | * | |
| Frangula purshiana | Tissue Culture | -- | -- | * | |
| Polygonum multiflorum | Root | -- | -- | * |