The discipline of pharmacy is familiar with a number of ways of harnessing the healing power of plants. One of the classic methods is extraction, which involves the dissolution of certain medicinally active components of a plant. A number of techniques are available for carrying out such an extraction, for instance using alcohol, water or oil; after all, a freshly brewed cup of coffee is nothing more than an extraction of roasted and ground coffee beans in water with subsequent filtration.

Extraction techniques are also used to manufacture WALA medicines and cosmetics, most prominently the procedure developed by Dr. Rudolf Hauschka for fresh plants using water, the result of which remains stable without the addition of ethanol (see also the report on the plant laboratory in viaWALA 02). It is also possible to use essences, which are aqueous-alcohol based extracts, and oil extracts, in which the active ingredients of dried plants are passed to the extract medium of oil.

Fragrant greeting from Persia
Today the WALA oil laboratory is heavy with a pleasant fragrance. It rises from cotton sacks that hold a valuable material: dried buds of sumptuous Damask roses. They originate from WALA’s Persian trade partner, which cultivates these certified organic roses in the mountains at an elevation of more than 2000 metres. Paul Pietrzyk and his colleague Daniel Stahovic use the rose buds to obtain an oil extract that will later form the basis for Dr.Hauschka Rose Body Oil. “First we crush the rose buds,” explains Paul Pietrzyk as he quickly disinfects the cleaned stainless steel containers one last time before exactly weighing and adding the rose buds. The buds are followed by peanut oil, which has likewise been precisely weighed. After stirring once quickly to prevent the sensitive oil from being exposed to too much oxygen, the lid is added and the container sealed.

In the rhythm of nature…
In the lid of the container are mounted a large spiral and a stirrer that extends down into the oil-rosebud mixture. Daniel Stahovic connects external hoses to allow water at 37 degrees Celsius to flow through the spiral and maintain the oil extract exactly at body temperature. Every morning and evening, the pneumatic stirrer gently churns the rosebud mixture, over the course of seven days.

This extraction procedure has certain similarities to the rhythmic manufacturing process developed by Rudolf Hauschka for aqueous plant extracts and has been included in the book of German Homoeopathic Pharmacopoeia. Alternating between steeping and stirring of the oil at body temperature is designed to mimic the polarities of rest and movement to which the plant is exposed in nature and helps better extract the herbal substances.

…body temperature has proven effective
And this procedure in fact works very well: a recent study at the University of Hamburg1 shows that extraction at body temperature is more effective than a method in which the active substances are extracted for only 4 hours but at a higher temperature of 60 to 70 degrees Celsius. The concentration of a group of active ingredients contained in arnica – the sesquiterpenlactones – was found to be higher than in the extract from the hot procedure; the same is true of the essential oils of chamomile and the carotinoids of calendula.

Only clear oil leaves our oil laboratory
After seven days, Pietrzyk and Stahovic filter the mixture through cotton cloths and a fine filter. During this procedure, Paul Pietrzyk constantly monitors the appearance of the final rosebud extract. “Only clear oil leaves our laboratory,” explains Susanne Geisel, group head of WALA oil production. Samples are also submitted to the in-house analysis laboratory, which conducts a range of tests before the oil can be approved.

The storage room contains additional sacks of dried medicinal herbs destined for extraction and use in a variety of WALA medicines and Dr.Hauschka skin care products. Nettle and birch leaves await processing for WALA Birken Rheumaöl (Rheumatic Birch Oil), while blackthorn blossoms undergo seven days of extraction for Dr.Hauschka Blackthorn Body Oil and a WALA dispersion bath oil used with the Junge bath instrument. “We process some 30 different medicinal herbs here,” reports Susanne Geisel. This means working in the oil laboratory is never boring. Every plant after all is highly unique, in terms of processing as well as fragrance.