3. Results
3.1. A comparison of the fuel characteristics between fossil-derived diesel and saturated alcohols
Having recently demonstrated the in vitro production of a broad range of fatty alcohols based on the activities of CAR and AHR enzymes (Akhtar et al., 2013), we surveyed the literature and compared the fuel characteristics of fossil-derived diesel and saturated fatty alcohols ranging in chain length from 2 to 12 carbons. Several fuel parameters relevant to diesel engines were considered, such as cetane number, viscosity and lubricity (Table 1). Short-chain alcohols such as ethanol and butanol were found to have poor lubricity and high combustibility which would increase engine wear and stress. On the other hand, longer alcohols (>10 carbon atoms long) exhibited high freezing points and extremely low vapour pressures which would render them ineffective in cold weather conditions. In between these two extremes, 1-octanol displayed an energy content, lubricity and viscosity similar to that of petroleum-derived diesel. We concluded that 1-octanol could potentially serve as a suitable fuel target.