Biotech Updates

Researchers Screen Fungal Isolates for Enzymes for Saccharification of Rice Straws

October 11, 2017
http://www.sciencedirect.com/science/article/pii/S0961953417300685!

Rice is one of the main agricultural products of Vietnam. Rice straw is a significant by-product, which, when used in a biorefinery, would contribute to the bio-based transformation of Vietnam.

To find novel efficient enzyme mixtures for the hydrolysis of rice straw and other agricultural residues, Vietnamese researchers led by George E.Anasontzis from Chalmers University of Technology in Sweden screened 1,100 new fungal isolates for their CMCase activity. The samples were collected from soil and decaying plant tissues around Vietnam.

The team selected 36 strains and evaluated them for their cellulases, xylanases, and accessory enzymes' activities. Most of these isolates belonged to the genera Aspergillus and Trichoderma. The team also identified promising isolates, such as A. brunneoviolaceus FEC 156, A. niger FEC 130 and FEC 705, and A. tubingensis FEC 98, FEC 110 and FEC 644. The produced enzyme mixtures of these selected strains released a huge fraction of the sugar content of alkali-treated rice straw.

The team found that the black Aspergilli are efficient in saccharification. Strains with low amounts of cellulases and xylanases but has enzyme mixtures with high saccharification efficiencies indicating a synergistic effect, were also identified.