Economic Botany



Economic Botany

The land and waters of the earth sustain a vast assemblage of plants upon which all other living forms are directly or indirectly dependent. These autotrophs have the remarkable property of capturing the inexhaustible energy of the sun to synthesise organic compounds which are vital for the existence of all life on earth. Organic deposits, such as coal, lignite, peat and petroleum are evidence of the photosynthetic activity of plants in the geological past. In addition, plants stabilise soil, conserve moisture and preserve an equable climate. After violent disturbances of the earth such as volcanic eruptions and upheaval of mountains, plants cover the denuded ground with a carpet which protects the surface from being washed away.

Before man domesticated animals and learned how to cultivate plants, he was unable to form settlements because his entire time was occupied with wandering in search of food. Presumably, prehistoric man lived on berries, succulent herbage and wild game which he could catch by primitive methods. These people lived in small groups and had a fierce struggle for existence against the carnivorous animals of that time and the vagaries of nature. Undoubtedly, their life was a hard one — a life in which only the hardiest could survive.

During the earliest and longest period of human history often called the Palaeolithic or ‘Old Stone Age’, which began one and three quarter million years ago, the concept of farming and domestic animals as such did not exist. The people of this Age were able to use fire and chipped pieces of hard stones (flint) into rough implements (such as crude hand axes and scrapers), which were used to remove flesh from animal hides.

During this period, the population was restricted to Africa, with a density of probably only 0.00425 persons per square kilometre and a total population of about 125 000 only. At present, there are 16.4 persons per square kilometre of the earth’s total land surface.

Presumably, agriculture began in the Mesolithic or ‘Middle Stone Age’ (12 000 -6000 BC) when man lived by the spear, the bow and the fishing net.This shift from a food gatherer to a food producer is assumed to develop independently at different times in different parts of the world. The Neolithic or ‘New Stone Age’ began about 6000 BC when ground and polished stone tools became the rule, and agriculture continued to develop.

 

Wood and its Uses

The need to satisfy thirst is even stronger than hunger. Prehistoric man quenched his thirst with water, from springs, streams and pools, and it continues to be the prime thirst quencher. With the domestication of animals, the man began to share with their young some of the milk that the female produced. Man’s earliest ‘beverage’ was probably the juice squeezed from fruits, but the civilized man found a vast array of refreshing and stimulating beverages for his enjoyment.  Unfermented or fresh juices (soft drinks), of course, contain no alcohol. Fruits most commonly used for preparing beverages are sweet orange, mandarin, sour lime, lemon, grapefruit, apple, mango, etc. Orange squash is the most popular of all. Fresh or bottled fruit juices are not only appreciated as an alternative to water in hot weather, but also contain useful amounts of vitamins, and contribute some calories through their sugar content. Present day soft drinks are, essentially, synthetic fruit juices compounded of sugar, fruit acids and other flavourings.  Although most adults drink one to two litres of water a day, much of this is in the form of coffee, tea, fruit juices, beer, wines, spirits or other liquids. In general, these are appreciated more for their taste and zest than for their nutritional value. Fruit juices are, of course, useful for their vitamins and potassium content. Coffee and tea by themselves have no nutritive value but may be a vehicle for large intakes of sugar, milk or lemon. The alcohol in beer, wines and spirits can serve as a source of energy.

Alcoholic Beverages  

Alcoholic beverages are mainly depressants that lower the activity of the brain. They are classified into two main groups, the fermented ones in which alcohol is formed by the fermentation of sugar and the distilled ones obtained by successive distillation of fermented liquors.  

The fermented beverages can be further classified into two groups according to the type of plant materials from which they are derived. If they are produced from fermented fruit juices (for example, juices of grapes, apple, pear, black currants, cherry, etc.) they are called ‘wines’, whereas if they are obtained from fermented cereals they are called ‘beers’. Wines and beers are among the oldest and most cherished of the man’s fermented beverages.

Spices, Condiments and Other Flavourings

Before turning our attention to spices, it would seem pertinent to know what they are and how they differ from condiments. In fact, it is difficult to draw a distinction between the two. Broadly speaking, spices are aromatic vegetable products of tropical origin that are used, in a pulverised state, primarily for seasoning or garnishing foods and beverages.They are characterised by pungency, strong odour and sweet or bitter taste. Included in this category are hard or hardened parts of plants, such as pepper, cinnamon, cloves, cardamom, ginger, turmeric, nutmeg and mace, allspice and vanilla. In ancient times, they were valued as basic components of incense, embalming preservatives, ointments, perfumes, antidotes against poison, cosmetics and medicines, and were little used in food. It was only in the first century AD that spices found their way into the kitchen.

The story of spices, condiments and other flavouring materials is one of the most romantic and fascinating chapters in the history of vegetable products as they are connected with many important events in man’s history, including geographical discovery, economic warfare, annexation of territories and all the vices of theft, envy and hatred of which man is capable. Historically, spices have been responsible for the rise and fall of empires and the great sea voyages to explore the distant corners of the globe. The search for spices by early European explorers led to the discovery of new continents and waterways.The westward voyages of Christopher Columbus were primarily intended to reach the ‘Spice Island’ of the Far East, but he failed in his basic objective. However, it resulted in the discovery of America. Although Columbus and his men did not find groves of nutmeg and cloves and jungles of pepper and cinnamon in the New World, they discovered some valuable and entirely new species, such as allspice and red pepper.

Medicinal Plants

The history of medicinal plants is intimately connected with the history of botany. Primitive man, in constant terror of diseases, lived at the mercy of nature. From the earliest times, tribal priests and medicine men (witch doctors) used various plants, minerals and animal organs, usually in association with strange rituals and incantation, to drive out the evil spirits which they believed to be the cause of the disease. Astonishingly, these magical rites seemed to help. In some primitive tribes, a victim of disease was half-buried in soil for several days to exorcise the malevolent spirits that had possessed him. Among the extremes of treatments was the chipping of holes in the skull to release the tormenting evil spirits. This theory of demoniacal possession lasted many centuries and exists even today in areas where people still live in primitive societies.

Records of early civilisation in all parts of the world reveal that a considerable number of drugs used in modern medicine were in use even in the ancient times. The use of plants for curing various human ailments figured in ancient manuscripts, such asThe Bible,The Rig-Vedas,The Iliad and The Odyssey and the History of Herodotus. Over 6000 years ago, the ancient Chinese were using drug plants. The Egyptians, Babylonians, Sumerians, Greeks and Romans, all developed their respective characteristic Materia Medica. On the other side of the world, the Aztecs, Mayans and Incas had all developed primitive medicine. Some of the ancient Egyptian textbooks ‘papyri’ (such as the Edwin Smith Papyrus and the Ebers Papyrus), written in early 1600 BC, indicate that the Egyptians had an amazingly complex Materia Medica. Apart from the names of many medicinal plants then known, the papyri also included several hundred recipes or prescriptions for various diseases.The Edwin Smith Papyrus (about 1750 BC) is now one of the prized collections of the New York Academy of Medicine.

In India, the ayurvedic system of medicine has been in use for over 3000 years. Charaka and Susruta, two of the earliest Indian authors had sufficient knowledge of the properties of the Indian medicinal plants. Their medical works the Charaka Samhita and the Susruta Samhita are esteemed even today as treasures of literature on indigenous medicine.