Effect of CH4/O2 ratio on fatty acid profile and polyhydroxybutyrate content in a heterotrophic–methanotrophic consortium
2015
Karthikeyan, Obulisamy P. | Chidambarampadmavathy, Karthigeyan | Nadarajan, Saravanan | Lee, Patrick K.H. | Heimann, Kirsten
Understanding the role of heterotrophic–methanotrophic (H–Meth) communities is important for improvement of methane (CH4) oxidation capacities (MOC) particularly in conjunction with bio-product development in industrial bio-filters. Initially, a H–Meth consortium was established and enriched from marine sediments and characterized by next generation sequencing of the 16s rDNA gene. The enriched consortium was subjected to 10–50% CH4 (i.e., 0.20–1.6 CH4/O2 ratios) to study the effects on MOCs, biomass growth, fatty acid profiles and biopolymer (e.g. polyhydroxybutyrate; PHB) content. Methylocystis, Methylophaga and Pseudoxanthomonas dominated the H–Meth consortium. Culture enrichment of the H–Meth consortium resulted in 15–20-folds higher MOC compared to seed sediments. Increasing CH4 concentration (and decreased O2 levels) yielded higher MOCs, but did not improve total fatty acid contents. PHB contents varied between 2.5% and 8.5% independently of CH4/O2 ratios. The results suggest that H–Meth consortia could potentially be used in industrial bio-filters for production of biopolymer/biofuel precursors from CH4.
显示更多 [+] 显示较少 [-]