Please see the attached file.
Thanks in advance,
1. Burke and Will died of beri-beri, a vitamin B deficiency.
2. Nardoo flour is made from finely grinding the spores of the Marsilea fern. Unless the capsule surrounding the spore is broken down none of the nutritional source found in the food can be digested. White flour must likewise be made by a milling process that removes the outer casing of wheat. In addition nardoo contains thiaminase (an enzyme that breaks down thiamine also known as vitamin B1). Soaking the nardoo in water leaches out this enzyme that if consumed will lead to beri-beri.
3. The aboriginals had learned over thousands of years how best to ...
Several paragraphs with web references examining the vitamin deficiency that afflicted the explorers Burke and Will upon consuming Nardoo flour that was harmless to the natives.