NOVELTY - Converting feed gas containing carbon monoxide or mixture of carbon dioxide and hydrogen to liquid product, comprises: (a) passing feed gas to gas contacting side of hydrophilic membrane; (b) retaining anaerobic microorganism in bio-pores and producing liquid product by contacting the feed gas with microorganisms; (c) passing fermentation liquid to liquid contacting side of hydration layer; (d) withdrawing liquid product from microorganisms by contacting the product with fermentation liquid; (e) recovering fermentation liquid containing liquid product; and (f) separating product.    USE - The method is useful for converting feed gas containing carbon monoxide or mixture of carbon dioxide and hydrogen to liquid product that is 1-6C alcohol, preferably ethanol (all claimed).    ADVANTAGE - The method: utilizes syngas (100%) thus it is simple, stable, economical and highly efficient; overcomes limitations of other fermentation methods and fermentor configurations; keeps microorganisms well confined and prevents catastrophic loss, thus leading to enhanced production of ethanol and eliminating gas transfer resistance and wetting of membrane pores; eliminates biological contaminants from liquid effluent thus removing need for filtering and/or recycling; and operates in smaller working volume.    DETAILED DESCRIPTION - Converting a feed gas containing at least one of carbon monoxide or a mixture of carbon dioxide and hydrogen to a liquid product under anaerobic conditions comprises: (a) passing the feed gas to a gas contacting side of an asymmetric hydrophilic membrane that defines a biolayer comprising many bio-pores open to the gas contacting side and having diameters of at least 1 mu m and that defines a hydration layer comprising a material that has a permeability less than permeability of the biolayer that controls the flow of liquid to and from the biolayer; (b) retaining an anaerobic microorganism in the bio-pores and producing the liquid product by contacting the feed gas with microorganisms; (c) passing a fermentation liquid to a liquid contacting side of the hydration layer to permeate a portion of the fermentation liquid from the liquid contacting side into bio-pores and into contact with the microorganisms; (d) withdrawing the liquid product from microorganisms by contacting the product with fermentation liquid, so that the liquid product flows with the fermentation liquid from the bio-pores to the liquid contacting surface, where the feed gas and liquid product are in co-directional flow; (e) recovering the fermentation liquid containing liquid product from liquid contacting side; and (f) separating the liquid product from fermentation liquid. An INDEPENDENT CLAIM is also included for converting the feed gas to a liquid product comprising 1-6C alcohol under anaerobic conditions, comprising: passing the feed gas to a gas distribution chamber; distributing the feed gas the outer surface of many hollow fiber membranes disposed in the gas distribution chamber with each fiber defining a biolayer; step (b) as above per se; passing the fermentation liquid into the lumens of the fibers; step (d) as above per se; recovering the fermentation liquid from the lumens of the fibers; step (f) as above per se; having an inner skin for permeating fermentation liquid to polymer layer and permeating liquid products from the polymer layer to the fermentation liquid; and a liquid recovery conduit in fluid communication with the second lumen ends of the hollow fiber membranes to recover fermentation liquid containing liquid product.