The production of edible microbial biomass in bioreactors is an attractive alternative to agriculture, which is a major consumer of fresh water, an emitter of greenhouse gases, and a cause of eutrophication. This study examines microbial food production by gas fermentation of two endotoxin-free Gram-positive H₂-oxidizing autotrophic bacterial strains, Nocardioides nitrophenolicus KGS-27 and Rhodococcus opacus DSM 43205. The supply of the gaseous substrates H₂ and O₂ by in situ water electrolysis was investigated as an alternative to providing them from an external source. N. nitrophenolicus KGS-27 produced ≤9.9 ± 2.0 mg of biomass L^–1 h^–1 and was not affected by in situ water electrolysis, which potentially produces growth-inhibiting reactive oxygen species. With R. opacus DSM 43205, in turn, electrolysis slowed growth considerably and resulted in a volumetric productivity of 2.6 ± 0.8 mg of biomass L^–1 h^–1, which was a quarter of what was obtained with the gases supplied externally. The macromolecular compositions of biomasses produced by the two cultivation modes using the two bacterial strains were rather similar containing approximately 33–37% protein, 28–56% carbohydrates, and 4–5% fatty acids of the cell dry weight. Relatively high protein concentrations and balanced amino acid profiles, comparable to those of casein and soy protein, were achieved with both strains.

中文翻译：

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通过革兰氏阳性H ₂氧化细菌的气体发酵生产食品用无内毒素微生物。

生物反应器中可食用微生物生物量的生产是农业的一种有吸引力的替代方法，农业是淡水的主要消耗者，温室气体的排放者和富营养化的原因。本研究探讨微生物食品生产通过气体发酵2无内毒素的革兰氏阳性ħ ₂ -oxidizing自养细菌菌株，类诺卡氏nitrophenolicus KGS-27和球菌红球菌DSM 43205.的气态底物的供给ħ ₂和O ₂通过原位对水电解进行了研究，以替代从外部来源提供水电解的方法。N. nitrophenolicus KGS-27产生≤9.9±2.0 mg的生物量L ^–1h ^–1且不受原位水电解的影响，原位水电解有可能产生抑制生长的活性氧。反过来，用不透明芽孢杆菌DSM 43205，电解可显着减缓生长，并导致2.6±0.8 mg生物量L ^–1 h ^–1的容积生产率，这是从外部供应的气体获得的四分之一。通过两种培养模式使用两种细菌菌株生产的生物质的大分子组成相当相似，包含约33–37％的蛋白质，28–56％的碳水化合物和4–5％的细胞干重脂肪酸。两种菌株均获得了与酪蛋白和大豆蛋白相当的相对较高的蛋白浓度和平衡的氨基酸谱。