**1. Introduction**

God created plants for the use of mankind and ordered man to make use of these herbs and trees for food and for medicine as reflected in His words recorded in the Holy Bible in the books of *Genesis* and *Revelation*. The book of *Genesis* Chapter 1 verse 29 reported and God said "Behold, I have given you every herb bearing seed, which is upon the face of all the earth, and every tree, in which is the fruit of a tree yielding seed; to you it shall be for meat." The book

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of *Revelation* Chapter 22 verse 1 also declared "And he showed me a pure river of water of life, clear as crystal, proceeding out of the throne of God and of the Lamb." Also, in *Revelation* Chapter 22 verse 2, it was written "In the midst of the street of it, and on either side of the river, was there the tree of life, which bare twelve manner of fruits, and yielded her fruit every month: and the leaves of the tree were for the healing of the nation" [1].

did not begin with food but was born out of the medicinal literature of China, Egypt, India, and Mesopotamia [4]. It was observed by botanical historian, Alan Morton, that agriculture was the occupation of the poor and uneducated, while medicine was the profession of the socially influential shamans, priests, magicians, physicians, and apothecians who were more

Phytochemicals—God's Endowment of Curative Power in Plants

http://dx.doi.org/10.5772/intechopen.77423

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Lists of different plants and herb concoctions for pharmaceutical purposes were dated back to 481 BC–221 BC in ancient China. Over the centuries, the written knowledge of herbal pharmaceuticals was contributed to by many Chinese writers [5]. The study of medicinal plants was not being neglected, and a full synthesis of ancient Greek pharmacology was compiled in *De Materia Medica* c. 60 AD by Pedanius Dioscorides (c. 40–90 AD) who was a Greek physician with the Roman army [6]. The lives of the European middle ages were based on agriculture in the fifteenth and sixteenth centuries until when printing came into limelight which did not publish dissertations on agriculture but rather preferred the lists of medicinal plants with descriptions of their attributes and inherent power (efficacy). Records had it in most ancient history that *Herbal* which was the first series of books written on plants indicated botany to form a part of medicine [3]. People who contributed to *Herbal* were mostly university gardens' curators [7], and compilations of classic texts in *Herbal* were mostly derived from *De Materia* 

The need for accurate and detailed plant descriptions meant that some herbals were more botanical than medicinal. Herbals made contributions to botany by initiating the science of plant description, classification, and botanical illustrations. Botany and medicine were the same up to the seventeenth century, but those books that emphasized medicinal aspects omitted the plant lore and eventually became the modern pharmacopeias; those that omitted medicine became more botanical which evolved into the modern plant description compilations called *Floras* and are often backed by specimens deposited in a herbarium (a collection of dried plants that verified the plant descriptions given in the *Floras*). The transition from *Herbal*

Medicinal plants are gaining popularity in usage due to a large number of people in search of health remedies with little or no side effect which is the problem of most chemically synthesized drugs. Considerable attention is presently given to the use of eco-friendly and biofriendly products from plant origin for the prevention and cure of human and animal health challenges (diseases) [9, 10]. This problem of side effects of most chemically based drugs has spurred the Western world to looking into natural products that are safe, effective, and affordable. It has been documented that 80% of the world's population has a strong belief in traditional medicine, especially drugs from plant origin for their primary health care [9, 10]. Medicinal plants, for example, neem leaves and stem bark (*Azadirachta indica*), pawpaw leaves (*Carica papaya*), mango leaves and stem bark (*Mangifera indica*), and Cinchona bark have been

likely to put their knowledge in record for posterity [3].

*1.1.2. The relevance of botany in medicine*

**1.2. Separation of botany from medicine**

*1.2.1. Relevance of medicinal plants*

to *Floras* marked the final separation of botany from medicine [8].

*Medica*.

From the work of creation, God made light on the first day followed by water on the second day and afterward created plants on the third day in the categories of grass, herb yielding seed, and tree yielding fruit, whose seed was in itself, that is, seed enclosed in fruit. This order was a divine one which no one can fathom as God is all-knowing and His understanding is unsearchable. God knew what the requirements for the growth of all these plants would be, and He ordered their creation after those requirements were met so that they could survive.

He created man lastly on the sixth day after all other things (creatures) had been made so that man could have dominion over them. He ordered man to use the herbs and tree bearing fruits for meat, that is, food, and for treating their illnesses as He understood the frailty of man. He knew all the requirements that man needed to survive and made provisions for them.

God created plants to serve man and put into these plants certain powers that are capable of healing and which in the modern times are now known as "phytochemicals." These phytochemicals are of different types according to their specificity in curing various diseases. Many individual plants were endowed with varieties of these chemical constituents, and the synergistic effects of these constituents also termed secondary metabolites endow on them their curative abilities. The healing properties of most plants are becoming more recognizable and preferable as most are associated with little or no side effect which is a common problem with the administration of most synthetic drugs (orthodox medicines) and the realization of the fact that many natural remedies carry their cures along with them [2]. Never are we reminded of Wordsworth's outburst: "The world is too much with us; late and soon, getting and spending, we lay waste our powers. Little we see in nature that is ours" [2].

#### **1.1. Objectives of the study**


### *1.1.1. The history of botany in relation to medicine*

Botanical science in a pure sense is the study of plants, and botany is the applied science which has in its interest the study of human use of plants. The studies that are mostly obvious in applied botany are agriculture, forestry, horticulture, pharmacognosy, weed science, economic botany, plant pathology, and ethnobotany that fall outside of modern botany courses [3].

The knowledge of plants especially in uses for food and medicine increased during the Neolithic Revolution. Protobotany which was the first prescientific written record of plants did not begin with food but was born out of the medicinal literature of China, Egypt, India, and Mesopotamia [4]. It was observed by botanical historian, Alan Morton, that agriculture was the occupation of the poor and uneducated, while medicine was the profession of the socially influential shamans, priests, magicians, physicians, and apothecians who were more likely to put their knowledge in record for posterity [3].
