Introduction

This patent identifies two Saccharomyces cerevisiae yeast strains capable of improving ethanol yields from starchy materials through one-step Consolidated Bioprocessing (CBP).

Technical features

This patent describes two Saccharomyces cerevisiae yeast strains that can efficiently produce ethanol from starchy feedstocks, such as corn, triticale and sorghum, as well as from agricultural by-products such as bran, potato and/or rice waste. These recombinant strains produce a selected mixture of glucoamylase and alpha-amylase enzymes capable of hydrolysing starch from different sources very effectively: 100 g/L of raw starch produce up to 50g/L of ethyl alcohol. Currently, the biological fermentation process requires large quantities of commercial amylolytic enzymes, which are a significant portion of production costs. Since these yeast strains within a CBP process reduce the amount of commercial enzymes that need to be added, overall production costs are significantly lowered. The technology has been validated in 100ml laboratory fermentation bottles and in 1 and 3 litre fermenters.

Possible Applications

• Bioethanol production from starch (corn, triticale, sorghum);
• Glucose syrup production from corn, triticale, sorghum and other agricultural waste (rice, potato).

Advantages

• Greater ethanol yield;
• Cost reduction (requires less enzymes);
• Ideal for agricultural waste reuse (circular economy).