Introduction to the Fundamentals of Traditional Chinese Medicinal Materials

An Overview of Traditional Chinese Medicinal Herbs: Definitions, Origins, Processing Methods, and Common Classification Systems

Traditional Chinese medicinal materials (TCM materials) form the essential material foundation of Traditional Chinese Medicine (TCM). Guided by TCM theory, they serve preventive, health-promoting, or supportive regulatory functions. Sourced from nature, they fall broadly into three categories: plant-based, animal-based, and mineral-based substances. Plant-derived materials constitute the largest group—for example, *Panax ginseng*, *Astragalus membranaceus*, *Angelica sinensis*, and *Lonicera japonica*. Animal-derived materials include Ejiao (donkey-hide gelatin), Lu Rong (deer antler velvet), and Dihuanglong (earthworm). Mineral-based materials include gypsum, cinnabar, and mirabilite. Importantly, all TCM materials must comply with national pharmaceutical standards and undergo standardized harvesting, regional processing, and rigorous quality control before clinical use. TCM materials are not used in their raw, unprocessed state; instead, they undergo specialized processing techniques known as “pao zhi” (processing or preparation). This is a distinctive TCM processing methodology encompassing cleaning, cutting, stir-frying, honey-frying, steaming, calcining, and other methods. These processes serve multiple purposes: removing impurities, facilitating storage and formulation, modifying pharmacological properties, reducing toxicity, enhancing therapeutic efficacy, or directing the action of the herb toward specific zang-fu organs or meridians. For instance, raw *Rehmannia glutinosa* is cold and cooling, excelling at clearing heat and cooling the blood; after steaming, it becomes prepared *Rehmannia* (*Shu Di Huang*), which turns sweet and warm and primarily nourishes yin and enriches the blood. Such empirically refined processing wisdom reflects TCM’s holistic principles of adapting treatment to time, place, and individual constitution. Based on therapeutic function and clinical application, TCM materials are commonly classified into categories such as exterior-releasing herbs, heat-clearing herbs, tonifying herbs, blood-activating and stasis-resolving herbs, qi-regulating herbs, and phlegm-resolving, cough-suppressing, and asthma-relieving herbs. Further classification according to the “four natures” (cold, hot, warm, cool) and “five flavors” (pungent, sweet, sour, bitter, salty) helps clarify their functional tendencies and compatibility logic. For example, Ephedra (*Ma Huang*), warm in nature and pungent in flavor, effectively disperses wind-cold; Coptis (*Huang Lian*), cold in nature and bitter in flavor, primarily clears fire from the heart and stomach. This systematic conceptual framework underpins clinical herb selection and formula design in TCM. It must be emphasized that the use of TCM materials must be grounded in TCM pattern differentiation and treatment—never applied simplistically without regard to individual constitution, pathomechanism, or environmental context. Contemporary scientific research continues to investigate the chemical constituents, pharmacological activities, and mechanisms of action of TCM materials, fostering integration between traditional knowledge and modern science. The public should approach TCM materials with scientific awareness, respect for tradition, and rational understanding—avoiding self-prescription or uncritical acceptance of exaggerated claims. With a long and rich history, TCM materials represent not only a vital component of China’s outstanding traditional culture but also a valuable resource worthy of deeper understanding and judicious application within today’s health care systems.