Method for Indirect Quantification of CH(4) Production via H(2)O Production Using Hydrogenotrophic Methanogens

Hydrogenotrophic methanogens are an intriguing group of microorganisms from the domain Archaea. Methanogens exhibit extraordinary ecological, biochemical, and physiological characteristics and possess a huge biotechnological potential. Yet, the only possibility to assess the methane (CH(4)) production potential of hydrogenotrophic methanogens is to apply gas chromatographic quantification of CH(4). In order to be able to effectively screen pure cultures of hydrogenotrophic methanogens regarding their CH(4) production potential we developed a novel method for indirect quantification of the volumetric CH(4) production rate by measuring the volumetric water production rate. This method was established in serum bottles for cultivation of methanogens in closed batch cultivation mode. Water production was estimated by determining the difference in mass increase in a quasi-isobaric setting. This novel CH(4) quantification method is an accurate and precise analytical technique, which can be used to rapidly screen pure cultures of methanogens regarding their volumetric CH(4) evolution rate. It is a cost effective alternative determining CH(4) production of methanogens over CH(4) quantification by using gas chromatography, especially if applied as a high throughput quantification method. Eventually, the method can be universally applied for quantification of CH(4) production from psychrophilic, thermophilic and hyperthermophilic hydrogenotrophic methanogens.