Chapter 8 - Photosynthetic hydrogen production bacteria breeding technologies

Abstract

Hydrogen is considered to be the most ideal alternative energy of fossil fuels. Photosynthetic bacteria can produce hydrogen under light and anaerobic conditions. Photosynthetic hydrogen production bacteria not only affect the energy consumption, hydrogen-producing activity, hydrogen-producing rate, and other factors of the biological hydrogen production system directly, they also restrict the industrial development of hydrogen production by photosynthetic organisms. Breeding highly efficient photosynthetic hydrogen production bacteria has become the main problem in photosynthetic hydrogen production technology. Hydrogen production by mixed photosynthetic bacteria is a coordinated metabolic action among multiple species. Compared with hydrogen production by pure bacteria, mixed bacteria have more advantages in the substrate use rate and hydrogen production efficiency. Many elements such as the temperature, inoculation ratio, illumination, and pH value can significantly affect the growth of photosynthetic bacteria and photosynthetic hydrogen production. Photosynthetic hydrogen production bacteria can use small molecules such as acetic acid, butyric acid, and lactic acid as the carbon source and hydrogen-producing matrix. Nutrients including the carbon source, nitrogen source, and their concentrations can greatly affect the growth and H2 production of photosynthetic bacteria. The continuous culture system and device of the photosynthetic microorganisms is an important guarantee for an effective photosynthetic H2 production.