(452d) High Value Products Derived From Biological Pretreatment

Biological pretreatment for breaking down lignin and hemicellulose has been identified as one of the research priorities as an alternative to thermochemical pretreatment processes of lignocellulosic biomass. In destruction of biomass, microorganisms have the ability to liberate compounds that could be recovered as co-products. This study depicts the biological pretreatment process in combination with mild thermochemical treatment to hydrolyze wheat straw, releasing high value products as well as fermentable sugars. Phanerochaete chrysosporium was used to pretreat the straw for up to three weeks at 37oC. Tween 80, lactic acid, and H2O2 were used in the sugar production analysis, and 0.1 % Tween 80 treated straw showed the best yield. It is also important to note that after mild acid hydrolysis (0.2% H2SO4) the total sugar recovery was also stable in the sample supplemented with Tween 80. To enhance hydrolysis, samples were subjected to mild acid treatment at 121oC/20 min. A total sugar content of approximately 18 g/L was detected in the first week sample, where the control gave approximately 6 g/L. However, the enzymatic hydrolysis gave no significant change in sugar level compared to the control. Therefore, the experiment suggests that the mild acid treatment may be a useful method when combined with biological pretreatment to extract the hydrolysable sugars. Decaying of biomass was observed by scanning electron microscopy (SEM). Fourier Transform Infrared (FTIR) spectroscopy showed a distinct absorbance at 1500?1800 cm-1, indicating the deposition of C=O stretching compounds, 1497?1530 cm-1 the aromatic skeletal, and 1383?1360 cm-1 for aromatic methoxy stretching. The result was further verified by fast pyrolysis GC/MS. The analysis of each individual peak after pyrolysis GC/MS was done and showed a clear increasing trend (approximately 3%) in the concentration of venylguaicyl and syringol, with the biomass incubation time was noted. This indicates that during biological pretreatment, lignin monomers such as venylguaicyl and syringol units can be extracted in high amounts after a mild thermal treatment, which can be further used as fuel compounds. Interestingly, a compound which can be used for the development of anticancer compounds was discovered among the new compounds after biological pretreatment process and is currently under characterization. Overall, this approach of biomass processing is a new way to utilize the biomass, not only for obtaining fermentable sugars, but also for the extraction of valuable bioproducts.