Nitrogen cycle feedstocks

The fact that menthol is produced from both renewable and fossil feedstocks allows for an interesting study in sustainability. In order to produce the same crop year after year, it is necessary to use fertilisers to replenish the nitrogen and minerals which the plant takes from the soil. Secondary metabolites such as menthol and essential oils occur at a level of, at most, only a few per cent of the dry weight of the herb. Therefore, in order to produce an economic return, it is necessary to use efficient, mechanical methods of cultivation and harvesting. A full life cycle analysis of menthol production reveals that production from cultivation of mint plants consumes more fossil fuel, produces more carbon dioxide effluent and has more environmental impact than either of the leading synthetic routes. 

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