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Biomedical subjects

N W Pirie

Publications and source records attributed to N W Pirie.

At least 19 recordsLinked to original sources
PubMed1994

Some factors controlling carotene destruction by chloroplasts in vitro.

Loss of beta carotene from moist leaf protein stored with a preservative, is closely simulated by the destruction of beta carotene by acetone extracted chloroplasts (stroma) suspended in acetone containing 30% water. During this exposure, stroma lose destructive ability, but it is restored by mercaptoacetate and other reducing agents. Stroma can therefore be used repeatedly. This catalytic process is activated by removing intrinsic inhibitors, predominantly calcium, by extraction at pHs less than 4, or by alum. The objective is to find inhibitors which would be acceptable in a food. That restricts choice. Citrate, tartarate and phosphate are among the more attractive possibilities.

Alum Compounds↗
PubMed1985

Fact and assumption in studies on the origins of life.

Proteins and nucleic acids organise metabolic systems very efficiently. Original forms of life may have depended on less efficient mechanisms which have been superseded in the course of evolutionary selection. Discussion and experiment on the origins of life should therefore not depend on the assumption that substances and mechanisms, now seemingly essential, were essential initially. Instead we should consider what might happen in a few million years on moist mineral surfaces, smeared with bituminous material, and exposed to UV light in a reducing atmosphere in the absence of predators. What little evidence can be gathered from differences in composition and metabolic behaviour between ancient and recently evolved species suggests that the trend in biochemical evolution is towards simplification.

Animals↗
PubMed1980

Space victualling.

Explore the source record for details and available documents.

Carbon Dioxide↗
PubMed1976

Food protein sources.

Work on food, planned by the U.M. (Use and Management) Section of the U.K. committe, was limited to sources of protein because we agreed that more problems calling for research were likely to arise in getting adequate supplies of protein than of other types of food. Deer meat can be produced on land too rough and exposed for sheep; parts of the work on their metabolism and food requirements necessitated building a mobile laboratory. The manner in which the nutritive value of maize is affected by changes in the ratios in which the component proteins are present, stimulated similar studies on barley and groundnut. There is good quality protein in coconuts and leaves but its use in human food is restricted by the presence of fibre. Methods for separating protein from fibre and other deleterious components were improved. In cooperation with scientists in India and Nigeria, the potential yield of protein-deficient foods. e.g. cassava, were 'ennobled' by growing micro-organisms on them with the addition of a cheap source of nitrogen.

Animals↗
PubMed1975

The yields of extracted protein and of residual fiber from potato haulm taken as a by-product.

In July the yield of protein extractable from potato haulm could be 600 kg/ha and the beginning of September it is 200 kg/ha. The yield of fiber containing 1 to 2% N is less affected by maturity. The annual waste of extractable protein, suitable for feeding nonruminants, is about 60,000 tons. The contribution that some small changes in conventional potato husbandry might make to minimizing this waste is discussed.

Animal Feed↗