Historical Development of Pharmacognosy

1.1 Historical Development of Pharmacognosy

1.1.1 Pharmacognosy in Ancient Times (Before the Nineteenth Century)

The medicines originated in Egypt and India. Medicines were recorded both in papyrus of Egypt about 1,500 bc and later in Ajur veda of India. In papyrus, crocus, dried ox-bile juice, castor oil, and so on were mentioned. In about 77 ad, Dioscorides, a Greek doctor, kept a record of about 600 kinds of crude drugs in his compiled book De Materia Medica, a book that had played an important role in pharmacolog and botany by the fi fteenth century. Ancient Rome also promoted it development. The Historia, written by Pliny (23–79 ad ), gave a brief account of nearly 1,000 species of plants, most of which could be used for medicines. Wild herbs were used to treat illnesses in the Soviet Union before the eleventh century.

From ancient times to the middle of the nineteenth century, pharmacology had been in its traditional stage for all countries in the world. At that time, knowledge about medicines came mainly from senses and practical experiences, and the major contents for any medicinal book were mostly about medical effectiveness and partly about its name, origin, morphology, and identifying sensory characteristics. Due to underdeveloped science, people could hardly know all the details about medicines.

Besides, it was hard for people to reach an agreement on them due to differences in location and personal experiences.

1.1.2 Pharmacognosy in Early Modern Times (1815–1930)

It was at the beginning of the nineteenth century that pharmacognosy came into its real being. In 1815, C.A. Seydler, a German who used the word “pharmakognosie” in his book named Analecta Pharmacognostica , was referred to as the father of pharmacognosy. Pharmakognosie etymologically means knowledge about crude drugs. In 1825, Martius, a German scholar, set up “pharmakognosie” as a subject to study in college, and then a new discipline named pharmakognosie emerged in natural science. According to Martius, pharmacognosy, as a part of merchandizing, was a study to research drug base taken from nature to test its purity and to check impurities or adulterants. From then on, German scholars published works, named pharmakognosie, on plant and animal drugs successively. In 1880, Gendō Oi, a Japanese scholar, translated pharmakognosie as pharmacognosy. Japanese early study of pharmacy was based on quoting and researching Chinese herbs.

In 1806, Serturner, a German, clarified the cell to be the basic unit of plant structure, and then microscopes were used to research the internal structure of crude drugs. In 1857, Schleiden published a book named Grundriss der Pharmakognosie des Pflanzenreiches (foundation of pharmacognosy of plants), in which he gave a detailed description of microstructure of a great many plant crude drugs. Later, Berg in 1865 and Vogl in 1887 published anatomical atlas of crude drugs successively, which furthered the development of identifying crude drugs by the use of microscopes, and then this method became the most important one to identify crude drugs.

Meanwhile, the qualitative and quantitative methods of chemistry were used in crude drug identification. Fluorescence analysis and chromatography were used in sequence in the latter half of the nineteenth century and in the beginning of the twentieth century, both of which enriched the research field of pharmacognosy and promoted a greater development than the early method of identifying crude drugs by shape and smell.

All in all, the reason why pharmacognosy has become an independent subject is closely related to the development of international traffic and trade at that time. In the first half of the nineteenth century, the rapid progress in international trade gave rise to an increase in variety of medicines and resulted in enlarging scope of raw materials and medium products. Crude drugs were sold after being broken down or crushed into powder. In order to hunt for profits, some merchants took advantage of the difficulty in identifying powder and usually mixed drugs at low prices with those at high prices, and even taking fake products as fine products.

Therefore, the problem of identifying the authenticity and quality of crude drugs arose. With advancement in bioscience and widespread application of microscope, pharmacognosy made great progress in the middle of the nineteenth century and finally became an independent subject. The early work of pharmacognosy was establishing quality standards for crude drugs in business.

1.1.3 Pharmacognosy in Modern Times (1930 to the Late 1990s)

Since the 1930s, development of biology and chemistry enriched methods and ways of studying goods pharmacognosy. The development of the bioassay of intensity of drug action (biological potency) advanced the study of active ingredients of crude drugs and strengthened quality evaluation of them. Chemical and physical methods, such as colorimetry, spectrophotometry, and fluorescence analysis, were all applied to identi fi cation of crude drugs gradually. When pharmacognosy developed in lines of morphology and chemistry, many new disciplines emerged.

For example, with accumulation of chemical composition of plants in type and number, a new subdiscipline-plant chemotaxonomy, came into being through exploration of chemical composition of plants and their genetic relationship. The new discipline not only had taxonomy signi fi cance but also pushed for new sources of crude medicines.

1.1.4 Period of Natural Pharmacognosy (At the End of the Nineteenth Century to the Early Twenty-First Century)

Going through the fi rst three stages of development, pharmacognosy became an established applied discipline with advanced technology and theory. In 1970s and 1980s, many universities canceled the “pharmacognosy” course from their curriculum.

However, at the end of this century, with humans “returning to nature” and uprising of modern life science, pharmacognosy has presented a strong vitality and broad prospects. Progresses in separation of the chemical composition, structure determination, and quantitative technology made ¹H NMR, ¹³CNMR, DNA fingerprint identi fi cation, etc. possible to be used in the identi fication of crude drugs thus promoting its standardization and normalization.

Through constant exploration, a batch of new developing points was made sure. In 1995, Huang Luqi fi rst mentioned the concept of molecular pharmacognosy in his paper Prospect of Application of Molecular Biology Technology to Pharmacognosy . This paper aroused a strong resonance in the circle. People with similar interests took whatever means to put forward their ideas and encouraged him to further the exploration and systematize the theory. Based on the encouragement he received, he worked with great effort for many years and published Molecular Pharmacognosy in Peking University Medical Press in June 2000. This book made the original pharmacognosy give rise to the birth of a new branch - molecular pharmacognosy.