When it comes to weaning the world's motorists off their addiction to fossil fuel, few would have bet on finding part of the solution in the pungent depths of elephant droppings and a Swiss compost heap.  a biochemical cocktail based on enzymes and micro-organisms found in elephant faeces and in rotting vegetable matter has the potential to revolutionise biofuel production by making it possible to mass-produce eco-friendly gasoline for the first time without relying on food crops, say the scientists.  a Dutch technology giant, DSM, has signed deals to introduce its new fermenting technique in test plants across Europe and the US, meaning ethanol, which currently makes up 4 per cent of all petrol in Britain, derived from crop waste and wood chips, could be available at the pump by 2015.  Research shows the new technology, along with other second generation or "2G" biofuels, could produce up to 90 billion litres of bio-ethanol in Europe by 2020 and displace more than 60 per cent of conventional petrol use as well as reducing reliance on crops such as maize, which has been blamed for fuelling the global fo