Dissertation

Development of Soy Formulate and Bioprocessing for Biological Ammonia Production via Hyperammonia Bacteria Fermentation

Bello, Ibrahim Adebayo

2023

Overview

Ammonia production, a critical industrial process, is currently dominated by the energy-intensive and environmentally detrimental Haber-Bosch method. To address this issue, a biological alternative harnessing rumen Hyper Ammonia-Producing Bacteria (HAB) is explored. The study focuses on developing a soy-based formulate for biological ammonia production via the HAB fermentation route. Firstly, a sustainable protein extraction method was developed and modeled using NH4OH, a recoverable and reusable solvent. The highest protein yield of 65.66% with minimal denaturation was obtained with 0.5% NH4OH concentration, 12 h extraction time, and a 1:10 (w/v) solvent ratio at 52.5 °C. Analysis of the empirical kinetic models for soybean protein extraction revealed that the So & MacDonald's model provided the best fit for the data, emphasizing NH4OH's viability as a sustainable solvent for plant protein extraction. The study further harnesses the potential of rumen HAB as a viable option to convert protein to ammonia. To establish a bioprocess option for ammonia production, the study investigated the influence of process parameters, such as alkalinity, pH, inoculum size, and substrate concentration, on microbial growth and biological ammonia production. Findings reveal that maintaining alkalinity stabilizes the media's pH during fermentation, with optimal conditions achieved at pH 7, a fermentation duration of 72 h, a 10% inoculum size, and a 10% substrate concentration. Significant media components, including K2HPO4, KH2PO4, Na2SO4, and soymeal protein isolate (SMPI), were identified through a one-factor-at-a-time (OFAT) design. A central composite design (CCD) using response surface methodology (RSM) further refined these components. The results showed that with the combination of the media formulation developed –K2HPO4 (490 mg/L), KH2PO4 (490 mg/L), Na2SO4 (64 mg/L), NaCl (100 mg/L), CaCl2.2H2O (640 mg/L), Na2CO3 (4.0 g/L), yeast extract (0.5 g/L), and SMPI (10%)– the observed ammonia yield was approximately 80 % higher than in previous studies, highlighting the potential of biological ammonia production as a sustainable and efficient alternative to the conventional Haber process. This notable increase emphasizes the uniqueness of this biological approach and also suggests the possibility of reviewing ammonia production methodologies. The results not only contribute to the expanding knowledge base but also offer valuable insights for optimizing biological ammonia production on an industrial scale. The implications of these findings may extend beyond the laboratory, providing an insight towards the development of environmentally friendly and economically viable processes in the area of ammonia production.

• Publisher: ProQuest Dissertations & Theses
• Subject: Agricultural engineering / Bioengineering / Food Science / Microbiology
• ISBN: 9798381430707