INDUSTRIAL CHEMICALS, COSMETICS AND PHARMACEUTICALS

As previously described, a number of native bushfoods, Victorian kelps, and plants used for essential oil production are also used or have potential for use in industrial, cosmetic and pharmaceutical applications.

Other species include:

a) Backhousia spp. - now being tested for plantation production;¹⁹⁵

b) common sneezeweed or `old man weed' (Centipeda cunninghamii), widespread in Victoria and is a potential medicine;¹⁹⁶

c) Duboisia spp. - used as a source of alkaloid extracts;¹⁹⁷

d) black wattle (Acacia mearnsii), widespread in Victoria and used elsewhere to produce high-quality tannin extracts; and

e) two species identified as containing chemicals with anti-viral activity - Dianella longifolia (flax lily)and Pterocaulon sphacelatum (a daisy)¹⁹⁸

The anti-viral properties of the last two named species were identified as a result of screening of plants known to be used by Aboriginal people for medicinal purposes.¹⁹⁹ Traditional Aboriginal culture used a multitude of herbal medicines, of which some knowledge survives. Dr Beth Gott records a dozen different plant groupings found in Victoria that are known for their medicinal use.²⁰⁰ In the early 1840s barilla, a plant ash rich in sodium and potassium, was produced on French Island (it had previously been produced in New South Wales). It was produced by cutting mangroves, dragging them above the high-water mark, burning stockpiles of stems and then bagging the resultant ash for sale. Some 30,000 kilograms of barilla was produced but the operation could not compete with chemically produced sodium and potassium.²⁰¹

The development of pharmaceutical drugs is a highly competitive sector that requires a huge investment ($400-$500 million) and about 10 years of research and development to develop a new drug (but it can be very lucrative). Many pharmaceutical drugs are derived from natural products, including 10 of the top 25 drugs currently in use.²⁰²

Systematic screening of the Australian flora for constituents useful for medicinal drugs was initiated in the early 1940s by the CSIRO and continued up until the mid-1970s, when it was scaled down.²⁰³ The CSIRO and its collaborators screened many thousands of plants, particularly for alkaloids but also for stock poisons and anti-tumour constituents. A number of potential anti-cancer agents were identified during this program. Screening of plants (a process known as `bioprospecting') continues, within Victoria notably by AMRAD Discovery Technologies Pty Ltd (established in 1993). It is one of only two companies undertaking this work in Australia (the other is in Queensland). However, two factors that discourage research into medical applications of native-plant extracts were identified by the CSIRO. One is the technical - screening tests have not always identified the activity of plant extracts that more elaborate (and costly) tests have shown to have anti-tumour or other medical benefits. The second factor was "the realisation that commercial benefits of [CSIRO's] collaborative screening activity were unlikely to be retained in Australia under the conditions then pertaining".²⁰⁴

The Committee inspected AMRAD's Burnley laboratories and spoke to key staff. The company collects plants, fungi and micro-organisms from around Australia and South-east Asia and screens them for compounds for use in pharmaceuticals. Trained botanists are contracted to collect specimens, targeting species not previously sampled. Endangered species and ethnobotanical knowledge are not targeted. The company has a very high-tech and impressive operation and conducts millions of assays each year, utilising a highly sophisticated system incorporating robotics and bar-coded tracking. The company operates through licensing arrangements, working in collaboration with large overseas companies - it provides raw material for a fee and then gains royalties through intellectual property rights if products are successfully developed.

In addition to conventional pharmaceutical uses, the growing popularity of herbal medicines could lead to an increasing demand for treatments based on traditional uses of native plants. In the United States increasing demand has been reported as sufficient to pose a threat to natural ecosystems.²⁰⁵

Duboisia

Duboisia is one of the few native Australian plants that has obtained mainstream agricultural product status. The export-oriented industry is based principally on the corkwood (Duboisia myoporoides). The primary product of the plant is alkaloid extracts, which are used for a number of medical purposes, including as a muscle relaxant and as a depressant. The gross value to Australia of the industry in 1991-92 was $3,755,000.²⁰⁶

The plant occurs naturally in New South Wales and Queensland, with current production from plants grown in southern Queensland. (Plants are also grown in India and Pakistan.) It has an interesting history of development - its medicinal properties were first recorded by a Brisbane physician in the 1880s, with production of hyoscine (the isolated alkaloid) commencing in 1940 - to meet war-time requirements. Further research into related species in the 1950s led to the high-yielding strains that provide the basis of the current Queensland plantations.²⁰⁷ The key trade product was patented by a major overseas drug company (Boehringer Ingelheim), in the 1950s. This led to a loss of control of value-added potential but ensured a stable market for the Australian-grown leaf. The extracted alkaloids are estimated to be worth $10-30 million and the formulated product $100-$300 million.²⁰⁸

Black Wattle

Black wattle (Acacia mearnsii) is considered "one of the world's highest yielding sources of condensed tannins".²⁰⁹ The wattle extract is primarily used as a tanning agent in leather manufacture. Indeed it is "recognised worldwide as a tannin extract of superior quality which has an important role in global markets".²¹⁰ Tannin extract is a concentrate produced through a process of shredding and leaching the bark.

The wattle tannin extract has an array of other current and potential uses. The tannins obtained from the bark are water-soluble phenolic compounds and such compounds have traditionally been used (and continue to be used) for converting animal skins into leather - hence the name tannin.²¹¹ But they are also used for an array of other uses including wood bonding adhesives (a use developed in the 1940s by CSIRO),²¹² as a treatment for preventing the corrosion of metals²¹³ and as a conditioning agent for drilling muds.

Black wattle is endemic to south-eastern Australia and is found throughout Victoria in a range of elevations and soils. Its distribution has been significantly reduced since European settlement, primarily because the once-extensive stands were stripped of bark and were not replaced. Tanning was one of Australia's first manufacturing industries, but there was indiscriminate harvesting - with a Board of Inquiry appointed in Victoria in 1878. Plantations were established (including at the You Yangs in 1887), but these were unsuccessful for a range of reasons, with the result that the supply of mature trees for bark became unavailable. Since the turn of the century tannin has been sought from overseas supplies - from black wattle plantations established in South Africa and other species from South America.²¹⁴

Black wattle is still grown in plantations in South Africa (the largest supplier), as well as Zimbabwe, Kenya, Tanzania, Brazil and, since the 1950s, in China (assisted by CSIRO scientists). Black wattle tannin extract currently used in Australia for commercial applications is imported from overseas.

Black wattles are also used for minor timber products - firewood and craftwork, and for conservation works - growing readily on disturbed sites.

Sector Strengths and Challenges

Victoria has a diversity of plant species that provide a large resource of chemicals to be explored for useful chemicals.²¹⁵ Current research is developing an inventory of chemicals in these plants and investigating the potential (particularly for pharmaceutical use) of many of these chemicals.

Challenges facing these sectors include that:

a) much of the relevant research is focussed on individual chemicals in isolation while the value of a plant extract may depend on the combination of chemicals which occur together naturally in the plant²¹⁶ - only limited research is being done on the biological activity of total plant extracts;²¹⁷

b) there appears to be difficulty in retaining commercial benefits of pharmaceutical research within Australia; and

c) where native species are lost (for instance, as a result of changes to land use and competition from weeds) potentially useful chemicals and combinations of chemicals in them may also be lost. ²¹⁸

Wild harvesting of plants for herbal treatments could exacerbate this problem.