The disclosure provides methods to improve the economics of the gas fermentation process. A fermentation process is integrated with an industrial or syngas process and an reverse water gas shift process. An intermittent supply of reverse water gas shift process feedstock from the reverse water gas shift process is provided to the bioreactor for fermentation. The reverse water gas shift process feedstock may supplement or partially displace the C1 feedstock from the industrial or syngas process. Whether the reverse water gas shift process feedstock supplements or displaces the C1 feedstock may be based upon a function of the cost per unit of the C1 feedstock, the cost per unit of the reverse water gas shift process feedstock, and the value per unit of the fermentation product, or may depend upon the target gas ratio of the feedstock to the gas fermentation process.

The disclosure provides methods to improve the economics of the gas fermentation process. A fermentation process is integrated with an industrial or syngas process and an reverse water gas shift process. An intermittent supply of reverse water gas shift process feedstock from the reverse water gas shift process is provided to the bioreactor for fermentation. The reverse water gas shift process feedstock may supplement or partially displace the C1 feedstock from the industrial or syngas process. Whether the reverse water gas shift process feedstock supplements or displaces the C1 feedstock may be based upon a function of the cost per unit of the C1 feedstock, the cost per unit of the reverse water gas shift process feedstock, and the value per unit of the fermentation product, or may depend upon the target gas ratio of the feedstock to the gas fermentation process.

An integrated process and system for the production of at least one gas fermentation product from a gaseous stream has been developed. The disclosure provides improved carbon utilization through both the recycle of a bioreactor tail gas via various different flow schemes and the employment of a CO.sub.2 to CO conversion system such as a reverse water gas shift unit. Recycling of the bioreactor tail gas and employment of a CO.sub.2 to CO conversion process provides for favourable H.sub.2:CO molar ratios of the feed to the gas fermentation bioreactor(s) for enhanced production of fermentation products. Bypass embodiments provide for optimal sizing of the reverse water gas shift unit to minimize cost.

An integrated process and system for the production of at least one gas fermentation product from a gaseous stream has been developed. The disclosure provides improved carbon utilization through both the recycle of a bioreactor tail gas via various different flow schemes and the employment of a CO.sub.2 to CO conversion system such as a reverse water gas shift unit. Recycling of the bioreactor tail gas and employment of a CO.sub.2 to CO conversion process provides for favourable H.sub.2:CO molar ratios of the feed to the gas fermentation bioreactor(s) for enhanced production of fermentation products. Bypass embodiments provide for optimal sizing of the reverse water gas shift unit to minimize cost.

Supplemented mixotrophic method. A mixotrophic fermentation method is disclosed including providing a naturally acetogenic organism; providing a fermentation medium comprising a carbon source and a supplemented non-sugar reductant; and culturing the organism in the fermentation medium, where both the carbon source and the non-sugar reductant are metabolized and a fermentation broth is formed, which contains at least one carbon-containing bioproduct.

The invention is directed to a process for producing one or more fermentation product in a multi-stage process including an inoculation reactor and at least one bioreactor. The inoculation reactor is fed a C1-containing gaseous substrate containing a reduced amount of hydrogen. The hydrogen is reduced to increase the proportion of CO in the C1-containing gaseous substrate being provided to the inoculation reactor. The inoculation reactor ferments the CO-rich C1-containing gaseous substrate and produces an inoculum, which is fed to at least one bioreactor. The bioreactor receives the C1-containing gaseous substrate, which may or may not contain reduced amounts of hydrogen, to produce one or more fermentation product. By providing a CO-rich C1-containing gaseous substrate to the inoculation reactor, both the inoculation reactor and the subsequent bioreactor(s), are able to have increased stability and product selectivity.

The invention is directed to a process for producing one or more fermentation product in a multi-stage process including an inoculation reactor and at least one bioreactor. The inoculation reactor is fed a C1-containing gaseous substrate containing a reduced amount of hydrogen. The hydrogen is reduced to increase the proportion of CO in the C1-containing gaseous substrate being provided to the inoculation reactor. The inoculation reactor ferments the CO-rich C1-containing gaseous substrate and produces an inoculum, which is fed to at least one bioreactor. The bioreactor receives the C1-containing gaseous substrate, which may or may not contain reduced amounts of hydrogen, to produce one or more fermentation product. By providing a CO-rich C1-containing gaseous substrate to the inoculation reactor, both the inoculation reactor and the subsequent bioreactor(s), are able to have increased stability and product selectivity.

A method for producing a fermentate including the steps of obtaining a fruit or vegetable extract, treating the extract with a hydrolytic enzyme, mixing the extract with a fermenting microorganism, water, and a growth media to produce a liquid composition; and incubating the liquid composition at a controlled temperature and a controlled pH to produce a fermentate. A method for killing or inhibiting the growth of a contaminating microorganism on or within a food product, and a food product including a fermentate having a cellular mass component from a fermenting microorganism, a fermented fruit or vegetable extract and a hydrolytic enzyme are disclosed. A fermentate produced by any one of the methods described is contemplated. The fermentate may be a concentrated liquid or a dry powder and has the ability to inhibit the growth of a contaminating microorganism by 100% when diluted to less than 5% (w/v).

A method for producing a fermentate including the steps of obtaining a fruit or vegetable extract, treating the extract with a hydrolytic enzyme, mixing the extract with a fermenting microorganism, water, and a growth media to produce a liquid composition; and incubating the liquid composition at a controlled temperature and a controlled pH to produce a fermentate. A method for killing or inhibiting the growth of a contaminating microorganism on or within a food product, and a food product including a fermentate having a cellular mass component from a fermenting microorganism, a fermented fruit or vegetable extract and a hydrolytic enzyme are disclosed. A fermentate produced by any one of the methods described is contemplated. The fermentate may be a concentrated liquid or a dry powder and has the ability to inhibit the growth of a contaminating microorganism by 100% when diluted to less than 5% (w/v).

The disclosure provides for the integration of a CO-consuming process, such as a gas fermentation process, with a CO.sub.2 to CO conversion system. The disclosure is capable of utilizing a CO.sub.2-comprising gaseous substrate generated by an industrial process and provides for one or more removal modules to remove at least one constituent from a CO.sub.2-comprising gaseous substrate prior to passage of the gaseous substrate to a CO.sub.2 to CO conversion system. The disclosure may further comprise one or more pressure modules, one or more CO.sub.2 concentration modules, one or more O.sub.2 separation modules, and/or a water electrolysis module. Carbon conversion efficiency is increased by recycling CO.sub.2 produced by a CO-consuming process to the CO.sub.2 to CO conversion process.