Organic substances in the soil go through oxidative decomposition depending on factors such as temperature, air, humidity, and pH balance. This is a slow burning (oxidation) event of organic substances. However, oxidative decay is hindered if one of the aforementioned factors is lacking. Then, a slow decay of organic materials in soil called humification takes place.

Humification occurs in an open system in contact with air. For example, early chemical processes start with leaves changing color in autumn. The break down and partial ingestion of leaves by soil organisms follows. During this time, water soluble carbohydrates and proteins leave the leaf tissue. What remains behind are plant structures like cellulose and lignin, which are not broken down yet. Since leaf shapes are not completely deformed, species identification can still be possible at this stage. In the decay step, however, the cellulose and lignin are decomposed by various fungi species and converted to humus.

Humic substances and their properties

Humic substances are intermediate products that occur as the result of organic materials going through a series of chemical reactions. These intermediate products are humic acid, fulvic acid, and humate. Their molecular weights are around 1.000-10.000 gr/mol, 10.000-100.000 gr/mol, and 100.000-10.000.000 gr/mol, respectively. Humic acids contain weak aliphatic (carbon chains) and aromatic (carbon rings) organic acids that are soluble in water when it has a base medium but insoluble under acidic conditions.

Fulvic acids with smaller size molecular structures can reach plant roots, branches, and leaves easily because they are soluble in water under all pH conditions (acidic, neutral, and basic). Thus, trace elements such as iron, zinc, copper, manganese, and boron can be easily transported to plant tissues via fulvic acid.

Humates, however, are insoluble in water. Only the portion of a humate called ulmic acid can dissolve in alcohol.

Major functions have been assigned to humic matter in the nutrient and carbon cycle, as they are inseparable members of the ecosystem. Plants capture significantly more nutrients from humic matter than from clay minerals. Even though they can be depleted from soil by certain agricultural practices in less than 50 years, they can still remain in natural soils, outside human activity, for hundreds or even thousands of years without being degraded. This very long presence in soil enables them to continue their functions longer. According to radiocarbon dating, humates can last approximately 1140 years; and humic acid and fulvic acid last for 1235 and 870 years, respectively, in natural soils.

Positively charged nutritious elements (cations) remain in the soil by binding to negatively charged (anions) in humic matter. Because this bond is weak, useful elements for the plant can easily be exchanged with another cation, becoming free and getting absorbed by the plant. On the other side, cations such as iron, copper, zinc, magnesium, manganese, and calcium, which are hazardous to plants when taken excessively, are held in the soil, bound to humic matter and thus not causing toxicity.

Another significant feature of humic and fulvic acid is their ability to form water bridges. Water bridges facilitate the movement of nutrient ions towards roots via soil solutions.

Aside from agriculture, humic matter, with its aforementioned properties, serve humankind in the industrial, environmental, and biomedical fields.

Industrial and environmental applications

Humic matter is utilized in the staining of leather works, as wood lining paint (natural blue color), as well as water based stripping material for furniture stains. Humic matter is also used in the production of durable, resistant papers in the paper industry, to provide mechanical strength to processed ceramics, and as an additive. It is also applied as a coloring, hardening, and plasticizing agent in plastic fabrication.

Humic and fulvic acids gain significance regarding their ability to form water soluble substances with many metal compounds containing radioactive elements in their structure.

In environmental chemistry, the main role of the humic matter is to remove toxic substances, human sourced organic chemical matter, and other pollutants from water. Calcium humate, obtained from humic matter, can bind and remove nickel, iron, cadmium, and copper in addition to radioactive elements produced at nuclear power plants from water.

Humus based filters are designed to treat sewage water and mud waste. Oils, stains, poisonous phenolic substances, and pesticides are removed from sewage via these materials. In poultry, humic substances are employed to absorb and eliminate the odor of waste gases.

Biomedical applications

Drugs for the treatment of human and animal diseases are developed from humic matter. These can be used for the treatment of viral and bacterial illnesses, in the prevention of blood clots, to cure infections, and to remedy estrogen deficiencies. Clinical studies have shown that common viral diseases of children’s respiratory tracks can be treated with fulvic acid supplements. A lot of medical research has shown that humic matter, especially fulvic acids, have the ability to provide protection against cancer causing viruses. In a study, laboratory mice were given ethanol to trigger gastritis and it was determined that humic acids supplied to mice led to a significant reduction in the harm gastritis caused. The fact that humic acids can form compounds with heavy metals, such as cadmium, enables the excretion of heavy metals from organisms.

In our universe there is no place for waste. Once every particle completes its task, it is returned in a different fashion to be assigned another job. Humification is a good example to this reassignment as a complex recycling event in the soil. It is amazing to observe everything being generated from one thing and everything converted into one thing so easily and in such a crafty, balanced, and organized fashion. In fact, the power and wisdom behind the conversion of the remains of millions of different organisms into a few similar substances to be employed in different tasks are no less amazing.

Imagine: I have just been cooked, and I am now waiting on a dish. Oh, what’s that? A metal thing with four prongs has just stuck itself into my chest, and it threw me into a shaking room with a gate moving up and down. There are, in this room, 32 flat and occluding rocks, some of which are sharp, while some are like millstones, all being lined up in a U-shape row. The frontal rocks have divided me into large pieces by squeezing and cutting. My pieces are pushed backwards by a soft shovel underneath. The rear rocks have made me almost like a paste, thoroughly mashing my pieces. Meanwhile, many taps on the right and left sides and in bottom of the room began flushing water upon me, and the carbohydrates within me have began dissolving by the pityalin enzyme (alpha amilaz) in this water. The flushing water contains substances such as lyzozym and antichore to eliminate any probable microbes within me.

I was fully softened and turned into something almost like gruel, when suddenly I was impelled by the actions of that soft shovel to an extremely tight tube inside of which movements continuously push me downward. A gate opened while I was being brought down and, as I was hoping to enter into a more spacious room and be saved from the compressive movements, I suddenly flopped into a well containing a light-colored liquid. I have come to know, while I was expecting to have some refreshment, that the liquid I flopped into was an acid capable of eroding marble (pH=0,8). I cried ‘Oh My God!’, but it was too late. This acid began to break my proteins down. The pepsinogen which was simultaneously being secreted by some cells over the walls of this large room and which were ineffective within an acid-free environment, became instantly activated by this acid and began to thoroughly break me up. Most of my proteins were broken. While I was wondering and asking ‘how come the liquid I flopped into is capable of eroding the marble but not capable of breaking up this well?’, I have come to notice that walls of the well were coated with a thin layer of mucous substance (membrane) which is unbreakable by acids.

I said ‘Oh My God! As long as you do not permit, these acids, which can erod marble, are not capable of damaging a soft tissue!’. Together with other foodstuff, I have been both blended and broken in this well-like room for about an hour. Later, the outer walls have again squeezed us, and we have been ejected yet again, this time into a new tube at an opposite direction to the one we were just pushed out of, by a sudden loosening and opening of a valve. This tube (called duodenum in Latin) has a length of about 15-18 cm and, appears as if lined up side by side. Here too, we felt wretched and were faced by a basic secretion (sodium bicarbonate) being ejaculated from a tap. This liquid was inactivating (neutralizing) the acids mixed with us, i.e., preventing them from damaging the unprotected walls of the tube which we were in.

Here again the amylaz, lipaz, trypsin, kymotrypsin and carbocsypolypeptidas attacked me, all of which break up, in a respective order, carbohydrates, fats and proteins of my ingredients, along with a lot many other enzymes, and they broke me up to my smallest constituents. Meanwhile, I started pondering the reasons why these enzymes, which are making mincemeat of me, are not damaging the tap (pancreas), which are composed of the same proteins, fats and carbohydrates that they come from. Then, I have come to realize that these enzymes could not become activated in pancreas tissue, since it does not have any activating factors, but they gained shredder features only after we arrived in the tube we are in, and only with the help of such factors which are being secreted from the intestinal walls.

After having been fully shredded within this narrow tube, a green liquid (bile), was poured on us as we were approaching its end. This detergent-like liquid was particularly responsible for shredding the fats in my ingredients. I understood, after all of this, that I was passing through a very excellent factory. As I and my fellow meatballs proceeded inside this narrow tube of approximately three meters long, no part of us remained un-shredded, except the cellulose fibers of plants such as parsley and onion which accompanied us. They continued their journey until arriving at a very thick and short tube. I have found out that their sap have been absorbed and their leftovers, after being amassed for some time, have been thrown into a cesspool called a toilet.

In the meantime, we have noticed that the walls of this tube are plicate and protuberant. These walls are apparently the places where our particles penetrate into another realm through two different ways. We understood that, via rather thin capillary channels situated inside these protuberances, we were being transferred into narrower tubes which contained two different (red and white) types of liquids (blood and lymph vessels). Now, there isn’t ‘me’ anymore, instead, there is only an ‘us’ which is composed of very smaller particles. While glucoses, the simplest forms of carbohydrates and aminoacids, the simplest forms of proteins are being transferred into the red liquid, our fat acid siblings are transferred into the white liquid of lymph vessels. Our glucose and aminoacid siblings have been carried by the red liquid to a factory called a liver. They are being returned to the red liquid after having passed through certain processes and being equipped with some useful characteristics here. But, the fats (lymphs) of the white liquid are, for some reason or another, being separately transferred into the red liquid, bypassing this factory. I learned the reason later: if the fat acids came to the liver together with glucoses and aminoacids, they would spoil this factory and kill its workers.

Finally, the red liquid carried us to tiny cell chambers numbering almost 100 trillion. Each of our tiny particles were sent to separate cells. Here, water, carbondioxide and energy were being produced by primarily coupling of our sibling glucose with oxygen. I learned that energy was needed for the functioning of these cells. Our fat siblings were also being utilized (consumed) for producing energy if glucoses were found insufficient for that purpose. Our amino acid siblings were being utilized (consumed) in the production of sound (strong) proteins and glucoses, and of energy in cases of the unavailability of fat sources for use in the cells’ structures. Excessive amounts of fat and glucose were being stored in these tiny cells. That is to say, I, who was a meatball at the beginning, was converted into water, carbondioxide and energy at the end of this painstaking journey. I was promoted (exalted) to the degree of humanness and rewarded a great deal of honor, as some parts of me became constituent of and some other parts of me assumed responsibility in vital cell functions of the human body.

After all these disintegrations and absorptions, some parts of us took their share in the structure of the body, while some others which were used in energy production including me were converted into a choky and dirty gaseous state called carbondioxide. We have been thrown back into the red liquid again since we would perhaps choke the cells we are within should our density increase very much. We have been brought to a marvellous and sponge-like factory named a lung, and composed of millions of vesicles, by being placed onto a molecule called hemoglobin, which is being pushed by a big pump. We have replaced the oxygen of the fresh air arriving to the lung vesicles. Now is the time for bidding farewell the human body. I thanked God, for I regained my freedom as a carbondioxide passing through and escaping from very dark and narrow places.

However, I was placed upon the leaf of a green plant after aimlessly roaming in the air for some time. After being filtered through the little windows (stoma) over the leaf, I was brought inside by the chlorophyll factory marvelously functioning inside these cells. Here, they forced me to unite with the water brought by tubules from the soil. Upon telling them that I cannot afford to do that, they instantly changed my true nature with solar rays and turned met into a chemical energy depot. I was no more a simple carbon atom; thus, I found a place for myself within an energy-emiting glucose molecule. I was in a position suitably convertible to starch, protein or fats in accordance with the true nature and genetic program of the plant I was within. Something incredible happened while I was swinging around on a green clover leaf. The leaf I was in has been eaten by a cow with real pleasure.

A new chapter has now opened inside the cow’s body. I was assigned with certain duties within the muscle proteins of my new host after having passed through a number of chemical processes. And I really enjoyed them. I was feeling myself more as an animal protein than a simple grass. By leaving the grass for a cow’s body, I was promoted (exalted) one more degree on the way to becoming manifestations of the divine attributes of God.

This blessed animal in whom I was assigned has been sacrificed during a Muslim feast of sacrifice, its meat ground into a meat grinder, and I have been served to you once again as a meatball.

Ali Uguz is a teacher of biology. He lives in Turkey.

And surely in the cattle (feeding on the pastures of the revived earth) there is a lesson for you: We give you from that which is within their bodies, (marvelously distinguished from) between the waste and blood, milk that is pure and palatable to those who drink. (Nahl 16:66)

Ruminants, probably the most abundant of the herbivores such as cattle, sheep and goats, are foregut fermenters with a four-chambered stomach (rumen, reticulum, omasum and abomasum) and are an essential component of utilizing marginal land in the world in a sustainable way.

In the verse above from the Qur’an, the Creator and the Sustainer of the universe draws our attention to many of the benefits we get from domestic animals. While the main message of the verse is easily understandable to the general reader, it also contains some concise hints, even descriptions about the physiological details of milk production in ruminants that would be fully understood and explained by science only centuries after the Qur’an was revealed. The purpose of this article is to explain this process in a general sense and milk production in some detail.

Mammals are generally categorized according to the dietary habits into three classes-flesh-eating (carnivore), plant-eating (herbivore) and both flesh and plant-eating (omnivore). In a sense, humans (omnivores) and carnivores depend on herbivores for their nutrition. Generally speaking, all humans and animals in the world have directly or indirectly benefited from the plants. The ability of herbivores to utilize plants as their main energy source is dependent on symbiotic microorganisms which live at various sites within their gastrointestinal tract. The animal provides the microorganisms with food and habitat for growth and the microorganisms provide the animal with fermentation acids and microbial protein.

Herbivores are divided into two types, those with post-gastric (hindgut) fermentation and those with pre-gastric (foregut) fermentation. Fermentation is a chemical process during which microorganisms obtain energy from organic products. Ruminants, probably the most abundant of the herbivores such as cattle, sheep and goats, are foregut fermenters with a four-chambered stomach (rumen, reticulum, omasum and abomasum) and are an essential component of utilizing marginal land in the world in a sustainable way. Rumen and reticulum contain millions of microorganisms, which form about 3 to 10 percent of rumen fluid.

A major reason why human beings keep ruminants is their ability to convert food which humans find inedible-or at least unpalatable-to food (meat, milk) which humans can eat. They play an important role in the livelihood of farmers throughout the world, providing sustenance such as milk and meat, manure for crop production, cash income from sales of their products and a safety net of capital assets to face risks and misfortune in harsh environments. Currently, humans obtain about fifty percent of the meat and most of the milk they consume from ruminants. Scientists who have conducted studied on ruminants have developed cow breeds, which have higher milk and meat production than traditional cow breeds, and thus supplied an important development to meet the nutritional requirements of humans.

Pre-gastric fermentation provides three important nutritional advantages to the host animal.

First, cellulose and other plant polysaccharides are brought into solution and become available as energy sources. Cellulose is the most abundant natural carbohydrate polymer in nature, but mammals do not produce enzymes that can degrade it. Ruminant animals utilize cellulose via a symbiotic relationship with ruminal cellulolytic microorganisms. During ruminal fermentation, microorganisms ferment the carbohydrates to produce energy, gases (methane and carbon dioxide), heat, and volatile fatty acids (VFA) in the rumen. Effective digestion of plants requires a means of dealing with cellulose, the most important structural material of plants, which is extremely insoluble and remarkably resistant to a chemical attack. Cellulose digesting enzymes that are called cellulases and produced by microorganisms are also present in the intestinal tract of several invertebrates that feed on wood and similar plant products. Rumen harbors the different functional groups of the microbial population, which is responsible for about seventy percent of total digestion in ruminants, and the ability to digest cellulose has been ascribed to a large number of bacterial, fungal and protozoal species isolated from the rumen.

The energy content of plants is low, and the herbivore must consume a large quantity in order to satisfy its energy requirements. Therefore, herbivores spend a lot of time eating; eight or more hours per day may be spent eating.

Secondly, the rumen microorganisms can utilize non-protein nitrogen for growth, converting it into microbial protein which becomes available to the host. Proteins provide the amino acids needed for maintenance of vital functions, reproduction, growth and lactation. Non-ruminant animals need pre-formed amino acids in their diets, but ruminants can utilize many other nitrogen sources because of their rare ability to synthesize amino acids and protein from non-protein nitrogen sources via a symbiotic relationship with ruminal microflora.

Ruminants possess a rumeno-hepatic nitrogen circulation mechanism, which does not exist in non-ruminant animals, in order to save nitrogen. By this mechanism, ruminants can be fed non-protein nitrogen sources such as urea and nitrate when nutrients are in short supply to obtain high quality milk protein. Feed proteins are degraded by microorganisms in the rumen via amino acids into ammonia. Ammonia is used by bacteria to build their proteins and any excess of it is absorbed through the rumen wall into the blood and then converted to urea in the liver. When a diet is low in nitrogen, large amounts of urea (which is normally excreted in the urine) return to the rumen where it can be used by the microbes. In non-ruminants, urea is always entirely lost in the urine. If ammonia levels in the rumen are too low there will be a nitrogen shortage for bacteria and feed digestibility will be reduced. Too much ammonia in the rumen leads to wastage, ammonia toxicity, and in extreme cases, death of the animal.

Thirdly, vitamin synthesis by the microbial population makes the ruminant animal virtually independent of dietary sources of all vitamins, except for vitamins A and D.

However, rumen fermentation also brings some disadvantages. First of all, rumen metabolism causes environmental pollution. Methane is produced as a natural consequence of the anaerobic fermentation; it is a potent greenhouse gas. Dairy farming is the largest agricultural source of methane, one of the greenhouse gases. Furthermore, the major environmental concern associated with the animal industry is ammonia volatilization, which increases atmospheric acid deposition because of the impact of nitrogen-rich excreta on the environment. Therefore, worldwide, scientific research projects have been carried out to find sustainable strategies for reducing emissions of the greenhouse gas methane and ammonia volatilization from domestic ruminants to the environment.

In conclusion, the symbiotic relationship between ruminants and ruminal microorganisms plays an important role in the recycling of nutrients between humans and plants. This relationship also contributes to human life by converting low quality nutrients (grass and hay) to high quality food (meat and milk). Humans will benefit more from ruminants as scientific knowledge about relationships between ruminants and rumen microorganisms advances.

Zubeyir Altuntas has a PhD in Molecular Medicine. He is a research associate in Immunology Department of The Cleveland Clinic.

* How do we leave traces of ourselves everywhere we touch with hardly visible fingerprints?

* Methods used for fingerprint identification…

* The signature we always carry with us: Our fingerprints…

A little girl in the US was kidnapped in 1993. Finding an opportune moment to escape, the child fled to a nearby neighborhood. Based on the girl’s statement, the police arrested a suspect, who told them about the other perpetrators and the car used for the abduction.

Realizing that there was missing evidence, the defendants asked for evidence of the child’s fingerprints from the car, as she had testified that she was in the automobile for hours. Strangely enough, despite scanning the entire vehicle, the detectives only found the fingerprints of the defendants. The joy of the latter made the child and her parents afraid that they would be unable to prove her presence in the car.

Leaving the rest of the story to the end, we will now focus on the fingerprint screening process, which sheds light on the frustration of the criminal detectives who were unable to find the child’s fingerprints in the car.

Innately found in the DNA structure of each and every individual, fingerprints are actually formed in the early embryonic stage with the infinite knowledge and might of the Creator. No two fingerprints have ever been found to be identical in every detail, despite billions of comparisons. This miracle alludes to the omnipotence and omniscience of God. Fingerprints are never exactly alike, but unique for each individual, except identical twins. To achieve this requires the infinite knowledge of the One Who distinguishes the fingerprints of all the living and dead, as well as those who are to be born. The fingerprints of identical twins are identical because the same egg has been inseminated by the same sperm and has then split into two, and thus the two babies have exactly the same DNA structure.

As is well-known, fingerprint identification stands head and shoulders above all other human identification procedures as the most reliable means of identifying individuals worldwide. The Qur’an speaks of the revival of every human being in all their particularities down to their fingertips, thus drawing our attention to the uniqueness and distinctive features of the fingertips of each and every individual. Only if one perceives the Qur’an as being the Word of God can they avoid the great difficulty inherent in attempting to explain how the Qur’an is able to refer to this issue; at the time of the revelation, 14 centuries ago, this matter was not known, rather, it only became known in modern times:

Does the human think that We will never assemble his bones (to resurrect him)? Yes indeed, We are able to make complete his very fingertips. (Qiyamah 75:3-4)

Fingerprints are friction whirl formations on the skin of the fingertips that are perpendicular, circular, oval, or made up of patterns parallel to each other. To make impressions of the fingerprints, the fingertips are pressed first on an ink pad, and then on a card; the ink impressions on the card retain the shape of the whirls. The fingerprints collected from items of evidence from a crime are matched (or not) with the suspect’s fingerprints. The fingerprint database archived in this way is the most reliable way to conduct criminal record checks when needed.

But how are the impressions of the fingerprints retained on the objects that have been touched? Fingerprints are deposited by the natural secretions of the eccrine glands which are present in the skin of the fingertips. When we touch an object, natural sweat secretions are discharged from the glands at the fingertips and these secretions remain on the surface in the shape of the whirls.

Fingerprints of children

How is it, then, that the fingerprint impressions of the child in the story could not be found at the crime scene? 99% of the secretion produced from the glands is water. The remaining 1% is of fatty acids, ethers, amino acids, and salts. It has been found, in contrast to the fingerprints of adults, which include long carbon chains linked by ethers, that the fingerprints of children have mostly non-etherized, short chains of fatty acids. These short chains of fatty acids on the fingertips of children are volatile. Thus, the fingerprints of children evaporate in 24 hours, while those of adults remain for longer periods. For this reason, fingerprint detection should be done as soon as possible in crime scenes in which children are involved.

We normally cannot see the impression left by the whirls. Criminal detectives, however, use electronic, chemical, and physical processing techniques that permit the visualization of invisible or hidden latent print residue from natural secretions of the eccrine glands on the fingertips. They then take the photographs of the impression to compare with fingerprint impressions of suspects and those on the database.

Amazingly enough, something as simple as sweat-which we mistakenly think is composed of pure water-can be used to solve serious issues as needed, because our fingerprints, which are hardly visible, leave clear signs of our presence everywhere we touch. It is not difficult to understand, then, that nothing has been created to vanish for ever; just as we leave our fingerprints everywhere, at every moment we also leave our own images in different forms of action in the minds of others and they are recorded on the heavenly plates. By the way, if you think that the suspects in the child abduction case were able to get away with it, you are wrong! Though her fingerprints could not be found in the car, the relief of the suspects did not last long. A small fiber from her clothing was found in the car, thus proving them to be guilty.

Because of their biochemical importance, the nucleic acids receive much more attention than the others. DNA was first isolated in 1869 by F. Miescher from cell nuclei. Nearly 80 years of research have been carried out to identify the major building block units and the basic structure of nucleic acids. DNA molecules from different cells and viruses vary in ratio of the four major types of nucleotide monomers, in their nucleotide sequence, and in their molecular weight. Four major bases (adenine, guanine, thiamine, and cytosine) are found in all DNA. The DNA isolated from different organisms and viruses normally has two strands in complementary double-helical arrangement, and it is the basic compound of genetic material (chromosomes). In its double-helical structure it has a 20 A (1 A=10-8 cm) diameter width and the nucleotides are repeated in every 3.4 A.

This polymeric molecule, DNA, is the chemical basis of heredity and is organized into genes, the fundamental units of genetic information. It was first demonstrated in 1944 in a series of experiments that genetic determination of the character (type) of the capsule of a specific pneumococcus could be transmitted to another of a distinctly different capsular type by introducing purified DNA from the former coccus into the latter. This agent (later shown to be DNA) was called ‘transforming factor’. Subsequently ,this type of genetic manipulation has become commonplace. Similar experiments have recently been performed utilizing yeast, cultured mammalian cells, and insects and rodents as recipients, and cloned DNA as the donor of genetic information.

DNA has the ability to replicate itself. It is this property that holds the genetic material in the same type and number sequence during the cell divisions. In prokaryotic cells, which contain only a single chromosome, essentially all the DNA is present as a single double-helical, two-stranded macromolecule exceeding 2 x 10- 9 in molecular weight. In eukaryotic cells, which contain either several or many chromosomes, there ate either several or many DNA molecules. 

The double-stranded structure of DNA can he melted in solution by increasing the temperature or decreasing the salt concentration. The denaturation of DNA is used to analyze its structure. Not only do the two stacks of bases pull apart but the bases themselves unstack while still connected in the polymer by phosphodiester backbone.

Careful examination of the model reveals a major groove and a minor groove winding along the molecule parallel to the phosphodiester backbone. In these grooves,proteins can interact specifically with exposed atoms of the nucleotides (usually H bonds) and thereby recognize and hind to specific nucleotide sequences without disrupting the base pairing of the double-helical DNA molecule. As easily seen, regulatory proteins can control the expression of specific genes via such interactions.

The genetic information stored in the nucleotide sequences of DNA serves two purposes. It is the source of information for the synthesis of all proteins of the cell and organism, and it provides the information inherited. Both these functions require that the DNA molecule serve as template – in the first case for the transcription of the information into RNA and in the second ease for the replication of the information into daughter DNA molecules.

DNA is likely to survive for millions of years in some conditions. Amber can provide some of the right conditions to preserve DNA. The most reliable report of DNA to date from amber is that of termite-like sequences from around 30 million year-old Dominican amber. The earlier recovery of DNA from a 20 million year-old magnolia leaf, near Moscow, was more remarkable because the leaf was preserved in a sequence of easily split soft clays and silts, interbedded with layers of volcanic ash.

Recent developments in genetics are providing very powerful new techniques for the analysis of DNA from remains of ancient organisms. The young field of ancient DNA research is less than a decade old but is growing exponentially. In spite of some serious technical difficulties, the study of ancient DNA promises to become a revolutionary research tool in archaeology; anthropology and molecular biology.The earliest report of retrieval of informative DNA sequences from extinct animals – in this case from the desiccated skin of a quagga, a member of the horse family which became extinct more than one hundred years ago – was that by A. Wilson and his colleagues in 1984. Shortly after this, DNA was isolated by S. Pbo from the skin of a pre-dynastic Egyptian mummy; it was shown by DNA hybridization that a small amount of recognizable human DNA was left in the ancient tissue. In 1988, the first report of an amplified ancient DNA sequence was made by S. Pbo and colleagues who retrieved it from a 7,000 year-old skull found in a peat bog.

It seems likely that studies of this kind will become even more popular in the near future. With the ancient DNA sequence studies, one of the most controversial problems in biology – evolution – will possibly be enlightened. No there is a drive to gather genetic information from indigenous groups to increase our understanding of human origins, history and migrations. Ancient DNA studies will play a very important role by providing a direct source of objective evidence on past populations, and perhaps the only reliable insight into the genetic characteristics of vanished peoples.

American Indians applied its leaves as a poultice to heal wounds, and brewed a cough mixture from its roots. Now its seeds are claimed to have medicinal uses ranging from relieving pre-menstrual syndrome to management of multiple sclerosis, alcoholism and atopic eczema.

The seeds contain approximately 15% protein, 24% oil and 43% cellulose and lignin. The fatty acids in the oil are thought to be important to health because the oil contains 65-85% linoleic acid (LA) and 7-15% gamma linoleic acid (GLA): LA is an essential fatty acid for the body which it cannot make but which it converts to GLA. GLA is one of the components of cells and a precursor of prostaglandins which regulate many body functions. However, the LA GLA conversion step may be blocked by a range of factors including excessive levels of blood cholesterol, a high proportion of certain fatty acids in the diet, ageing, alcohol intake and diabetes.

Supplementing the diet with evening primrose oil (EPO) by-passes the conversion step, thus providing for the presence of GLA in the body. A recent World Health Organisation report suggested that 3% of the total calorific intake of adults should be in the form of essential fatty acids, this figure rising to 5-6% for children and pregnant and lactating women. GLA can be provided by several other sources as well, e.g. borage oil and blackcurrant oil, both of which contain a higher concentration of GLA than EPO but not as much LA.

The quality and composition of EPO used in commercial manufacturing is currently the subject of much research and monitoring work. In the UK research is concentrated on obtaining GLA from other sources e.g. by fermentation from the fungus mucor javanicus.

A concentrated oil from evening primrose, borage and blackcurrant seeds, is now undergoing clinical trials and may be used in second generation oil products of the future. EPO is already used in a variety of beauty and hygiene products, including cosmetic and skin care products, shampoos and soaps.

Trials have been curried out to investigate claims of the effectiveness of EPO in treating many diseases and conditions, including multiple sclerosis, cardiovascular disease, asthma, atopic eczema, cancer, obesity and premenstrual syndrome. So far the results have been variable but some genuine clinical effects have been seen.

Millions of dollars have been and are being spent on developing new methods of extracting useful natural products for the benefit of mankind. We are now seeing a widespread desire to return to natural resources to cure various ailments. Let us hope that, before mankind destroy their environment, they will come to realize the importance of nature’s medicine-cabinet, and give thanks where it is due. Without that giving of thanks, mankind will not practise the humility and compassion necessary if our common resources are to be preserved both for ourselves and for future generations.