Botanicals now represent an important source of raw materials for the food industry, as well as for the cosmetic and pharmaceutical ones because of their nutritive, aromatic and therapeutic properties. Although many medical systems have been based on the use of plants, scientists are still involved in research that aims to discover new active constituents of herbs. However, a few classification charts have already been issued and they take as criteria either the phytopharmaceutic elements or their medical effect.
There are several categories of active constituents, among which the most important are:
Alkaloids are nitrogen based substances that can be found in coffee (caffeine) and cocoa (theobromine) beans, tea (theophylline), opium poppy (morphine) or nightshade (nicotine). They have a wide range of therapeutic effects such as analgesic, sedative and stimulating. For instance, because of its emollient, sedative and antitussive properties, the poppy is a soothing remedy for coughs and sore throats, case in which it comes in the form of lozenges, but poppy syrup is also sold in drug stores. However, herbs containing alkaloids as active constituents can have also a psychotropic, narcotic and hallucinogenic effect. This is why the cultivation of some alkaloid containing plants is legally regulated in many countries.
Flavonoids are to be found especially abundant in fruit: apple (quercetin), citrus species (rutin), grapes (epicatechin), berries (anthocyanins and proanthocyanidins), and walnuts (myricetin). Another flavonoid source is represented by green vegetables (hesperidin) and onion (kaempferol). This family of active constituents of herbs has a high hypoallergenic effect and is also known to have beneficial influence upon tumors, inhibiting their growth. Their antioxidant activity is useful with hearth conditions and cholesterol.
Poliphenols have a stimulating effect upon the immune system. They can be extracted from fruit like strawberries, apricots and cherries (coumarin), apples, peanuts, oranges and pineapples (ferulic acid), but also from other types of plants such as manuka flower (scopoletin), coneflower (chicoric acid), lavender and cinnamon (coumarin). They also have anti-inflammatory properties and can have a lowering effect upon blood pressure. Coumarin administration is forbidden in combination with anti-coagulants as it stimulates the blood flow through the veins and reduces capillary permeability. Scopoletin also has hormonal indication, stimulating the release of serotonin, able to reduce anxiety levels.
Anthraquinones and saponins
Anthraquinones and saponins are glycosides. The active constituent that can be extracted from plants like Indian aster, Japanese knotweed, senna and aloe (emodin) belong to the first category and has proved to be helpful in diabetes type 2 treatment. The same phyto-element, when extracted from rhubarb, is used to slow the evolution of pancreatic cancer. It is also known for its laxative and stomach soothing effect. Saponins are available in most vegetables and help with cholesterol absorption. This, combined with their antioxidant activity improves the state of the circulatory system and reduces the risk for heart diseases.