Abstract
Herbal medicines and botanicals have long been used as sole or additional medical
aids worldwide. Currently, billions of dollars are spent on botanicals and related
products, but minimal regulation exists regarding their purity, integrity, and efficacy.
Cases of adulteration and contamination have led to severe illness and even death
in some cases. Identifying the plant material in botanicals and phytomedicines using
organoleptic means or through microscopic observation of plant parts is not trivial,
and plants are often misidentified. Recently, DNA-based methods have been applied
to these products because DNA is not changed by growth conditions unlike the chemical
constituents of many active pharmaceutical agents. In recent years, DNA barcoding
methods, which are used to identify species diversity in the Tree of Life, have been
also applied to botanicals and plant-derived dietary supplements. In this review,
we recount the history of DNA-based methods for identification of botanicals and discuss
some of the difficulties in defining a specific bar code or codes to use. In addition,
we describe how next generation sequencing technologies have enabled new techniques
that can be applied to identifying these products with greater authority and resolution.
Lastly, we present case histories where dietary supplements, decoctions, and other
products have been shown to contain materials other than the main ingredient stipulated
on the label. We conclude that there is a fundamental need for greater quality control
in this industry, which if not self-imposed, that may result from legislation.
Key words
molecular markers - botany - barcoding - authentication - botanicals
