Alkaloids are organic chemical compounds found in a variety of animals, plants, and fungi. 

These chemicals contain carbon, hydrogen, and nitrogen, and may also contain oxygen and sulfur, and rarely, elements like chlorine and phosphorus. Researchers have identified thousands of alkaloids that occur in nature, and there may be many more. 

Here, we will briefly discuss the chemistry of these complex chemical compounds and review common products that contain alkaloids, including products you may be using today. 

Where Did Alkaloids Come From?

Alkaloids occur in nature. It is uncertain why plants and animals evolved to contain alkaloids, but there are theories. Alkaloids may be waste products produced from a buildup of chemicals the organism cannot use or excrete. Another theory posits that alkaloids are a natural evolutionary reaction to pressures or threats in the environment, and they give the organism some kind of defense. 

For example, kratom alkaloids may have evolved to protect the Mitragyna speciosa tree from insects like ants, termites, and fungi that are common in humid jungle environments. In animals like the poison dart frog (Phyllobates terribilis), alkaloids may have evolved to discourage predators from eating them. Alkaloids may have developed in fungi to insulate fungal cells from a variety of microscopic threats and animal predation. 

When Did Human Beings Learn About Alkaloids?

Alkaloids were not identified until the advent of science, but human beings have been using them for a long time. Those who practice traditional or folk medicine have been exploiting the unique properties of alkaloids for thousands of years. 

Ancient Egyptian, Chinese, and Sumerian physicians may not have been able to identify phytochemicals, but they knew how to take advantage of the compounds in plants like hemp, (Cannabis sativa), opium poppies (Papaver somniferum), the blue lotus flower (Nymphaea caerulea), and others. They used alkaloid-rich plant and animal materials to treat many different complaints. Evidence suggests that these substances were used in a variety of medicines for exhaustion, toothaches, headaches, back pain, nightmares, nervousness, inability to concentrate, and other afflictions. 

Are There Different Kinds Of Alkaloids?

Alkaloids fall into several main groups based on their characteristics, and most are members of the indole and isoquinoline groups. Other groups include tropane, harmala, steroidal, piperidine, and more, which contain far fewer members but are just as important. 

Indole Alkaloids

This major group of chemicals shares structural similarities common to indoles, an organic compound. Indoles can be found in serotonin, a neurotransmitter, and tryptophan, an amino acid. Indole alkaloids are common in plants like kratom, kava kava, St. John’s Wort, passionflower, and others.

Isoquinoline Alkaloids

This major group of alkaloids is similar to indoles in some ways. They are structural isomers of quinoline, which means they contain the same elements and the same number of atoms in their makeup as quinoline, but the bonds between the atoms are different. They are common in plants like poppies, magnolia trees, plants in the barberry family, and others. 

Tropane Alkaloids

Tropane alkaloids are based upon tropane, a chemical composed of carbon, hydrogen, and nitrogen atoms. These alkaloids can be found in deadly nightshade, coca, mandrake, and other plants. Tropane alkaloids are enormously important and have given us powerful drugs, including cocaine, scopolamine, and atropine. 

Harmala Alkaloids

These alkaloids are common in wild rue (Peganum harmala), coffee beans, passionflower, and tobacco leaves. Plants that contain this alkaloid can be found in ayahuasca, a psychoactive drink sometimes used in South American shamanistic rituals. It does not seem to be psychoactive alone but may facilitate the activity of other psychoactive compounds, making them more effective. These alkaloids may affect our brain’s reward system by stimulating higher serotonin levels and enhancing dopamine. 

Steroidal Alkaloids

Steroidal alkaloids are similar in structure to sterols, with the addition of nitrogen. Steroidal alkaloids include batrachotoxins found in poison dart frogs, bufotoxins found in the skin of some toads, and the leaves of the common boxwood tree (Buxus sempervirens). Solanum alkaloids, a form of steroidal alkaloid, are toxic and can be found in the green parts of tomatoes and potatoes, where they may serve as an organic pesticide.

Piperidine Alkaloids

These compounds can be found in many plants. Piperine, an alkaloid, gives black pepper its bite. Other piperidine alkaloids include lobeline, found in Lobelia species and some other plants, and solenopsin, an alkaloid found in fire ant venom. 

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Why Are Alkaloids Important Today?

Alkaloids are important for many reasons. They are used in pesticide production to protect our food, and their therapeutic value is impossible to deny. Alkaloids have been used to create many effective and powerful medicines like morphine and lidocaine.

Morphine

Morphine is a powerful alkaloid that can be extracted from the opium poppy. This alkaloid was isolated in the early 1800s and was used extensively in the Civil War. It has a long history of use in pain relief and gave rise to more powerful drugs like heroin. While they can be dangerously addictive, these medicines are effective painkillers and have saved many lives. Modern versions of this alkaloid include synthetic forms of opioids. 

Lidocaine 

This powerful local anesthetic makes dentist visits painless and can be used for minor surgeries. Lidocaine was developed from novocaine, which in turn was developed as a replacement for cocaine, which contains tropane or pyrrolidine alkaloids.

What Consumer Products Contain Alkaloids? 

Many consumer products wouldn’t be the same without alkaloids. Here are just a few things that contain them. 

Coffee – Coffee contains caffeine, theobromine, theophylline, trigonelline, and other alkaloids. These chemicals, especially caffeine, may increase your metabolism, put more oxygen in your bloodstream, and provide a temporary boost of energy. 

Ephedrine Medications – Some decongestant medications contain ephedrine, an alkaloid. This compound can open airways and increase your heart rate and blood pressure. This can increase your metabolism, increase the level of oxygen and nutrients in your blood, and may even help break down fat. Ephedrine may help clear the head and improve concentration. 

Organic Pesticides – Anabasine, an alkaloid, can be found in some organic pesticides that contain tobacco powder. These products were widely used before the invention of safer alternatives.

Tea – The alkaloids in tea depend on what kind of tea it is. Most traditional teas, like black and green varieties, have caffeine, theobromine, theophylline, and other alkaloids. These compounds may provide energy. Theophylline can be useful in treating respiratory conditions such as asthma, by working as a bronchodilator. 

Kratom – Kratom contains a medley of alkaloids with numerous qualities. It has a high concentration of mitragynine and associated alkaloids like 7-hydroxymitragynine, speciogynine, and more. These alkaloids have a variety of beneficial properties that may boost the metabolism and improve mood, depending on the product.

Hot Sauces – Peppery hot sauces are rich with piperine and capsaicin, spicy alkaloids. Capsaicin may help clear the sinuses and boost metabolism, which can aid with weight management. It is approved by the FDA as a pain reliever.

Alkaloids can also be found in potatoes, tomatoes, cinnamon, ginger, and many other foods, herbs, and spices. 

Why You Should Care 

Knowing about the power of alkaloids is important If you are a consumer who is interested in taking a more active role in your healthcare. This knowledge can save you money, and it may help you identify products that could improve your lifestyle. It can also make you an informed voter when topics of botanical supplements are discussed, which can be important if you’d like to protect your access to these natural compounds.