Planting some new ideas

Press, 29 March 1980, Page 16

Planting some new ideas

By

JEROME BURNE,

“Sunday Times,” London

Dr Norman Bissett, of the Department of Pharmacy at Chelsea College, University of London, is to announce officially next month a search for a needle in a haystack. The haystack is the Herbarium at Kew Gardens, which contains more than five million plant specimens. The needle is the estimated 0.4 per cent of them that may have a medicinalor commercial ■use. Concern over- both the limits to mineral resources and the side-effects of modern drugs has led to renewed interest in the possible use of plants as raw material for industry and for healing. Seven years ago a project at Harvard uncovered 5000 plants of possible medical interest from an examination of two and a half million specimens.

Dr Bissett says: “We hope to have a better success rate than the Harvard study, as we shall be looking for industrial and agricultural uses as well.” His project will involve 10 graduate students over five, years and wil cost about SI.SM. The attempt to raise the money will be launched .on April 4. The possible value of just one discovery for large scale medicinal or agricultural use can be judged from the case of the rosy periwinkle, from Madagascar, -which helped to raise the recovery rate from Hodgkin’s disease from 19 per cent to 80 per cent. Its key ingredient is vincristine, and in 1976 sales of vincristine were worth more than 524 M., Other exciting possibilities are already emerging. The euphorbia, otherwise known as the gopher plant, found in south-west-ern America, has hydro-

carbon sap almost identical to crude oil. Another candidate for research is jojoba,- which . produces beans containing , oil identical to sperm whale oil.' Similarly guayle, a hardy desert shrub, that pro-, duces rubber. At present, fewer • than 30 plants supply 95 per cent of the world’s ca•lories, but research could change this. The buffalo gourd, for instance, is a hardy plant that thrives in semi-arid areas and its seeds are 35 per cent protein. The tawi bean, similar to soya bean, is also very hardy and can be made into cooking oil. The pods of the carob tree contain more sugar than beets or cane.

Bissett’s researchers will be looking for and storing on a computer the uses to which the plants in the Herbarium are put in various parts of the world. If,

for example, a plant has similar uses in different parts of the world, then it is reasonable to suppose; there is some ' chemical basis for this.

. The plant collection at Kew is the world’s largest. “I suppose you could say that it was one of the fruits of the empire,” says its director, Peter Green. “One hundred years ago

there was obviously great interest in plants and their uses. They were sent to us for cataloguing by missionaries and district officers, and we’d mount our own expeditions. We have Darwin’s collection here, for example. “But -with the replacement of plant products

with synthetics around the turn of the century, interest dropped off and bot*any took a back' , seat to the more dramatic fields like DNA. research. That is beginning to change.” ; But while. Bissett’s pro-' ject will be concentrating on the herbarium, there is another part of Kew where, in a sense, the process of selection has al-

ready been done. This is the museum of economic botany, which has a collection of plants that may be useful to man.

:■ The museum is presided over by the charming and acerbic . Miss Angel. “When I heard about Dr Bissett’s - project at the herbarium I was a - little

surprised, to put it mildly,” she said. “I mean,, we have the lot here, gums, spices, medicinal plants, dyes, fibres, oils, poisons —. over a million specimens of stuff that ,has been used somewhere .or that someone thought might be useful. “Of course, it’s not as much used as we’d ..like it to be. In fact, it hasn’t been . catalogued ■■ since 1867. and . the stuff just keeps piling, up: AU. we can do is to note it and store : it. Put oh & computer, it, could be reaUy valu-. able.”

...' She .added: ’‘Every time 'we hear of. an. expedition. going up . the . Amazon to look . for . some medical herbs, we look at each other. Wh’ve probably had the stuff they’re looking for for the last 120 years.” It seems very likely. Research on. euphorbia, the hydrocarbon plant. for example, is now bn the. verge of Yet in Miss Angel’s mahogany, glass-fronted cabinets there are several bottles of euphorbia oil. still clear and yellow. “Those probably' date from about 1874,” she says airily.