On the Complexity of Simples, Pharmacognosy, and Actaea Racemosa W
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University of Richmond UR Scholarship Repository Biology Faculty Publications Biology 2017 On the Complexity of Simples, Pharmacognosy, and Actaea Racemosa W. John Hayden University of Richmond, [email protected] Follow this and additional works at: https://scholarship.richmond.edu/biology-faculty-publications Part of the Plant Sciences Commons Recommended Citation Hayden, W. John. “On the Complexity of Simples, Pharmacognosy, and Actaea Racemosa.” Sempervirens Summer/Fall 2017: 6-7. This Article is brought to you for free and open access by the Biology at UR Scholarship Repository. It has been accepted for inclusion in Biology Faculty Publications by an authorized administrator of UR Scholarship Repository. For more information, please contact [email protected]. 6 Sempervirens, Summer/Fall 2017 ON the CompleXIty of SImples Pharmacognosy and Actaea racemosa Article and illustrations by W. John Hayden, Botany Chair. harmacognosy, a discipline at Pthe intersection of botany and medicine, deals with knowledge about medicines derived from plants (Youngken 1950). A central goal of pharmacognosy is the accurate and consistent taxonomic identification of medicinal plants and medicinal plant products. Unlike drugstore pill bottles, medicinal plants in nature do not come with labels. One aspect of pharmacognosy, then, is the identification of whole plants Figures 1 and 2. Root and rhizome of Actaea racemosa as seen in cross section. Dark- found in nature. Much as in field gray regions represent first-formed (primary) xylem, light gray represents later-formed (secondary) xylem. Figure 1. Root; central diamond-shaped area of primary xylem; the botany and plant systematics, this Maltese cross–like pattern develops as secondary xylem is added to the root. Figure 2. aspect of pharmacognosy involves Rhizome; xylem in the form of radially elongate patches of cells; primary xylem is inner- learning to recognize species by most. Figures 1 and 2 redrawn by W. John Hayden from Wintermute (1905). overall appearance (gestalt), or by dichotomous keys, or both. nosy also strives to provide means passes a staggering array of forms. Seldom, however, do entire plants for identifying isolated and dried It is disparity of form that allows possess desirable medical properties. plant organs, whether intact, sliced, allergists to identify pollen grains Rather, depending on the species, diced, or powdered. Identification caught floating in air or investiga- useful compounds tend to be con- of simples is, thus, a particularly tors to identify fragments of leaves centrated in just one or a few plant challenging aspect of pharmacog- or stems found at crime scenes. organs. In the case of Actaea race- nosy, which by necessity adopts the Pharmacognosy similarly exploits mosa (Black Cohosh), the Virginia tools and techniques of comparative this fundamental disparity of plant Native Plant Society’s 2017 Wildflow- microscopic plant anatomy. This ar- form. The whole point, of course, er of the Year, medicinal properties ticle explores anatomical aspects of is to guarantee correct identity of are concentrated in the roots and Black Cohosh used in pharmacog- natural medicine ingredients and to rhizomes (see sidebar). For other me- nosy to aid in identification of this guard against adulteration. dicinal plants, leaves, flowers, fruits, significant medicinal plant. Much A noteworthy aspect of the roots or seeds are prized. of the information discussed here and rhizomes of Actaea racemosa is Typically, once a medicinal was developed in the late 19th and that their internal tissues are yellow, plant is found, only the organs with early 20th centuries, but remains a somewhat unusual feature that medicinal properties are harvested, relevant today. certainly helps in identification when and these crude bits of plant matter Before delving into the details confronting an apothecary’s simple. are known as simples. Simples of Black Cohosh’s microscopic But other plants in the Buttercup are usually dried for storage and structure, it is worth noting that the Family (Ranunculaceae) and the subsequently may be shredded or diversity of plant form (sometimes closely related Barberry Family pulverized. Obviously, it is just as referred to as disparity) is pervasive (Berberidaceae) have similar yellow important to be confident of the at all levels of biological organiza- pigments in their roots and rhizomes. identity of one’s stockpile of sim- tion. From whole plant architecture Consequently, additional anatomical ples as it is to know their sources in to the microscopic bumps on pollen details of each organ are required to the field. Consequently, pharmacog- grains, the plant kingdom encom- assure correct identification. Sempervirens, Summer/Fall 2017 7 ROOTS vidual vascular bundles, resulting Roots of vascular plants always in elongate radial strands of xylem Black Cohosh have a central core of water-conduct- tissue (Figure 2). In contrast, most ing xylem tissue, flanked by patches dicots produce secondary xylem in in the Wild: of sugar-transporting phloem. The the form of concentric rings—the pattern of xylem and phloem, as same pattern seen in growth rings on Let It Be! viewed in root cross sections, may tree stumps. take the form of a simple narrow In summary, yellow roots with a lack Cohosh is in demand ellipse, a triangle, a diamond, or a Maltese cross pattern of xylem and Bas a medicinal plant be- polygon of five or more sides. Most yellow rhizomes with multiple, radi- cause it produces a number of often, young roots of Black Cohosh ally elongate, patches of xylem will confirm unknown samples as Black biologically active compounds. have a central diamond-shaped patch of xylem cells, but many other Cohosh. Now, imagine the documen- In addition to antioxidant caf- plants also have essentially the same tation of anatomical details such as feic acids, multiple steroidlike pattern. The pharmacognocist must these for all plants with important triterpenes, and a number of then turn to older roots. In Actaea, medicinal properties, and you have a different alkaloids and amines, additional (secondary) xylem cells glimpse of the discipline of pharma- are present. In short, there are form along the sides, but not the cognosy. Knowing one’s simples is no many different molecules that tips, of the young root’s initial, simple matter! v interact with the nervous sys- diamond-shaped, patch of xylem, re- tem and hormonal regulation. sulting in a distinctive Maltese cross WORKS CITED In fact, so many biologically pattern in older roots (Figure 1); Wintermute, R.C. 1905. A treatise active compounds are present this is unique to Actaea. In contrast, on Macrotys. Drug Treatise No. that scientific deciphering of most dicot roots add secondary xy- XIII, issued by Lloyd Brothers, lem in a pattern that quickly assumes their collective modes of action Cincinnati. a circular outline. The distinction is a complex and ongoing en- Youngken, H.W. 1950. Textbook of between older roots of Actaea and pharmacognosy. The Blakiston Co., deavor. Nevertheless, Black Co- just about everything else is clear-cut. hosh remains a popular herbal Philadelphia. medicine, widely available in STEMS. health food stores as a dietary Unlike roots, xylem and phloem tissue in stems of flowering plants supplement. While the Virgin- form distinct clusters called vascular ia Native Plant Society takes bundles, usually with xylem cells no position on the efficacy of occupying the inner portion of the Black Cohosh in treating any bundle and phloem present in the of the several conditions for outer portion. In young stems of which it has been and contin- eudicots these vascular bundles are ues to be promoted, VNPS disposed in a ring near the stem Sempervirens (ISSN 1085-9632) is the quar ter ly newsletter of the Virginia Native is vigorously opposed to the surface. Sections of young rhizomes Plant Society, Blandy Experimental Farm, collection of Black Cohosh, or (horizontal basal stems) of Actaea 400 Blandy Farm Lane, Unit 2, Boyce, Va. racemosa reveal a notably large 22620, 540-837-1600, [email protected]. Nan- any other wild plant, from the cy Vehrs, President; Nancy Sorrells, Editor; wild for medicinal purposes. number of vascular bundles, a salient Karen York, Office Manager. Original Black Cohosh is amenable to detail, but not definitive for iden- material in Sempervirens may be reprinted tification. However, the pattern of if credit is given to the Virginia Native cultivation; therefore, demand accumulating additional (secondary) Plant Society, to Sempervirens, and to the for herbal Black Cohosh should author of the material, if named. Readers xylem cells marks Actaea rhizomes are invited to send letters, news items, and be met without depletion of its as unique among medicinal plants. queries for consideration. E-mail items to native populations. v Via secondary growth, over time, Nancy Sorrells at [email protected]. Next submission deadline: Oct. 30, 2017 new xylem cells are added to indi-.