Patent ID: 8497091

Claim:
A method of producing a compound originating from a polysaccharide-based biomass comprising: at least one of a saccharification step that produces a sugar solution containing 1) a monosaccharide and an oligosaccharide or 2) a monosaccharide or 3) an oligosaccharide from a product obtainable by hydrolyzing the polysaccharide-based biomass; a fermentation step that ferments the sugar solution containing the monosaccharide and oligosaccharide or 2) a monosaccharide or 3) an oligosaccharide originating from the polysaccharide-based biomass; and a treatment that removes a fermentation inhibitor with the use of a separation membrane having pores having an average pore radius as measured by a positron annihilation lifetime spectroscopy, of from 0.8 nm to 4.00 nm having a glucose removal rate and an isopropyl alcohol removal rate which simultaneously satisfy the following relationships (I) and (II) when a 500 parts per million (ppm) aqueous glucose solution at pH 6.5 at 25° C. and a 500 ppm aqueous isopropyl alcohol solution at pH 6.5 at 25° C. are respectively permeated through the membrane at an operation pressure of 0.5 MegaPascals (MPa), 1) prior to the saccharification step and in the step prior to the fermentation step or 2) prior to the saccharification step or 3) in the step prior to the fermentation step: Glucose removal rate≧80% (I) Glucose removal rate−Isopropyl alcohol removal rate≧20% (II).