What are the best ways to use medicinal plants?

Herbal teas: infusion, decoction, maceration

Harking back to the remedies of our grandmothers, the herbal tea is undoubtedly the best-known way of benefiting from plants, notably in their dried form (1). The principle is simple: the plants are immersed in water in order to extract the water-soluble compounds. But this somewhat generic definition actually encompasses various preparations which differ according to how they are extracted.

Infusion: for delicate plants

A popular choice whether for refreshment or a therapeutic drink, an infusion consists of pouring simmering water on a plant (at a temperature of around 80-90°C). The water should not be boiling so as to avoid damaging the most sensitive compounds. Infusion is a particularly suitable method for the delicate parts of a plant, such as the flowers and leaves, as well as for aromatic plants rich in volatile compounds from which we get essential oils.

How long it should be left to infuse depends on the part of the plant used. Allow 5 minutes for flowers, or aromatics prone to bitterness. For an infusion of leaves (such as moringa, which helps maintain normal blood sugar levels) you can allow up to 10 minutes (2-3).

For maximum extraction and preservation of the active principles, it’s important to cover the cup while it’s infusing and to press the plant well once infused.

Decoction: for the tougher parts

For the stronger, more fibrous parts of a plant – such as the seeds, roots and bark – decoction is the preferred method. This intense extraction process differs from infusion in that it starts off cold.

The plant is sometimes crushed beforehand so that its compounds dissolve better. It is then plunged into cold water which is gently brought to the boil, and after boiling for several minutes, it is taken off the heat. The mixture is then covered and left to continue infusing before being filtered (pressing the grounds well) and drunk.

The boiling and infusing times vary depending on the plant and the part used. For example, in the case of a decoction of nettle root (which supports prostate health in particular), the recommended boiling time is usually 1 minute followed by 10 minutes’ resting time (4).

Cold maceration: for mucilaginous plants

When they come into contact with water, plants rich in mucilage release a viscous substance with soothing, emollient or laxative properties (5). Examples include marshmallow root, mallow flower and flax seeds or psyllium seeds (6-8).

To give the mucilage time to swell in the fluid, it’s important to soak the plants in cold water for a period of 10 hours. This is called cold maceration or cold soak. It’s also suitable for plants that contain heat-labile compounds (those broken down by heat).

Unlike alcohol, water does not have good preservation properties. So in order to prevent the spread of bacteria, make sure the mixture is not macerated for too long, and that it is drunk within 24 hours.

Mother-Tincture

Used in the production of homeopathic remedies, mother-tinctures are the result of macerating fresh plants in strong alcohol, ideally titrated between 60°C et 90°C, for anywhere from a few days to several weeks. Calendula, arnica and harpagophytum, good for digestion, are among the best-known (9-10).

They are difficult to make yourself as they require a high degree of precision and attention to detail. It’s important to know the plant’s moisture content in order to establish the correct plant-alcohol ratio. In the French Pharmacopoeia, an alcoholic tincture comprises 10 parts alcohol to 1 part plant (dry weight).

Highly-concentrated, a mother-tincture is normally either administered in drops, used topically, or taken orally, diluted in a large glass of water. Due to its alcohol content, it is not recommended for pregnant women or nursing mothers, or for those suffering from liver problems or a sensitive stomach.

Plant extracts

Plant extracts are very similar to mother-tinctures, although the solvent used is not alcohol-based. The active substances are usually extracted by macerating the plants in water or glycerine which produces a liquid extract.

This liquid extract can then be converted into a soft or dry extract, by eliminating all or part of the solvent. This is achieved either through lyophilisation (freeze-drying then sublimation) or spray-drying (in which it undergoes rapid evaporation by passing a current of hot air over it).

Dry plant extracts are used, amongst others, in the production of dietary supplements, in capsule, or less often, tablet form.

Their primary attraction lies in the process of standardisation which ensures a consistently high minimum content of active principles in each capsule. The concentration thus remains the same across each pot, and even each batch: in this respect, it’s the best galenic form in terms of stability and efficacy. This kind of titrated extract makes up the majority of SuperSmart’s medicinal plant supplements.

For example, Bacopa monnieri leaves, which help maintain cognitive function, owe their nootropic properties to their bacoside content (11). So by taking a supplement with a high dose of these specific saponins, you maximise the chances of obtaining optimal benefit from their expected effects.

Plant powders

Easy to sprinkle onto a smoothie or a salad dressing, plant powders have become popular in recent years. In the pharmaceutical industry, they are also used in the manufacture of tinctures, capsules and tablets.

With a generally very small particle size, these powders are obtained from plants that are dried, pulverised and then sieved. This format is particularly suitable for woody plants that are hard to infuse as well as those with a high mineral content.

One of the best-known is spirulina in flakes, which not only promotes energy and vitality, but is incredibly nutrient-rich: it contains plant proteins, magnesium, vitamins A, B, E, K... (12)

Another plant in powder form that can be diluted in a hot drink, for example, is maca, which supports sexual health and fertility. (13-14).

Powders are, however, less stable than whole plants (with a significant risk of oxidation). Some of their active principles may also be lost when they’re crushed.

Compresses, poultices and lotions

Medicinal plants can also work through the skin when used in the form of poultices, compresses or lotions.

In the case of a poultice , the plant is applied directly to the skin, having first been softened in hot water or crushed to a paste. It needs to be left to sit for around 20 minutes, and renewed, if necessary, after a few hours.

While green clay poultices are popular for their purifying and decongestant properties, especially for the joints, ginger poultices, which support good respiratory health, are particularly good for helping to get rid of mucus (15-16).

Based on the same principle, a compress is basically a clean cloth soaked in a plant infusion or decoction.

Lotions combine heavily-diluted plant preparations: infusions, decoctions, mother-tincture dilutions… When massaged into the body, they are a gentle way of relaxing muscle tensions or soothing irritated or redness-prone skin – particularly lotions based on German camomile or witch hazel (17-18). In the form of an eye wash, a cornflower formulation provides genuine relief from the effects of excessive screen time.

Other ways of using medicinal plants

There are so many ways of using medicinal plants that it’s difficult to produce an exhaustive list.

Suffice to say you can also find them in the form of:

• essential oils(aromatherapy) and hydrosols or hydrolats (hydrosol therapy) (19);
• glycerine-macerated flower buds (gemmotherapy) (20);
• medicinal wines or spirits for their appetite-stimulating and digestive properties;
• inhalations for decongesting the airways;
• aromatic baths for relaxing the muscles;
• sitz baths for easing rectal circulatory disorders;
• mouthwashes for treating oral health problems (21);
• gargles for soothing sore throats.