A review finds that renewable plant parts can share important chemicals with destructively harvested roots, bark and heartwood in five species.
The review examines published evidence for phytochemical similarities between traditionally harvested plant parts and renewable aerial tissues in Myrica esculenta, Pelargonium sidoides, Warburgia salutaris, Litsea chinensis and Aegle marmelos. The studies reported shared compounds and compound groups, including gallic acid, salicylic acid, warburganal, polygodial, flavonoids and other phenolic substances.
The authors describe plant-part substitution as a possible conservation measure for slow-growing medicinal species. They stress that alternatives must be assessed species by species using chemical analyses and further pharmacological and toxicological studies, rather than assumed to be equivalent because they come from the same plant.
What the plant parts share
The review reports that renewable aerial parts of the five plants can contain chemical profiles comparable to those of traditionally used roots, bark or heartwood, although the amount of particular compounds varies among species. In Myrica esculenta, small branches were reported to match stem bark in total flavonoid and phenolic content. Leaves and stems of Pelargonium sidoides and Aegle marmelos were reported to contain gallic acid, salicylic acid and other bioactive acids at levels equivalent to those found in underground parts. The reviewed evidence also includes shared alkaloids, glycosides, tannins and phenolic compounds, with comparisons supported by methods such as HPTLC, HPLC and LC-MS/MS.
Evidence and remaining tests
This is a review of published phytochemical evidence for five representative medicinal plants, not a new clinical or field experiment. Similar chemical profiles do not by themselves establish equal therapeutic effects or safety. The authors note that metabolite levels can differ with plant organ, age, growth stage, season, genotype and environmental conditions. They call for broader comparisons and rigorous laboratory, animal and toxicological studies before substitutions are widely implemented, along with standardized harvesting and quality-control measures.
