Screening of bacterial and fungal strains for cellulase and xylanase production using distillers' dried grains with solubles (DDGS) as the main feedstock

Iram, Attia
Çekmecelioğlu, Deniz
Demirci, Ali
Bioenergy is one of the most promising solutions for the environmental problems of using non-renewable energy resources. Bioethanol is a form of bioenergy produced from food crops, such as corn, wheat, and sugarcane. Distillers' dried grains with solubles (DDGS) is the by-product of corn and wheat ethanol production in the dry mill process and has a high nutritional profile. The undigested carbohydrate components in DDGS and proteins can be utilized as the feedstock to produce microbial cellulases and xylanases as the value-added products. Currently, several bacterial and fungal strains are used to produce such enzymes by using expensive feedstocks for commercial preparations. In this study, several bacterial and fungal strains have been evaluated to explore the potential of hydrolyzed DDGS as the main feedstock for these hydrolytic enzymes production. Maximum cellulase production of 0.592 IU/ml was observed for Aspergillus niger (NRRL 1956) on the eighteenth day and stable high production of xylanase of 34.8 IU/ml was obtained for Aspergillus niger (NRRL 567) on day twelfth during shake-flask fermentation. Hydrolytic enzyme production by Bacillus subtilis (NRRL NSR352, DSM 17766, and NF1) was relatively lower (0-0.261 IU/ml for cellulase and 1.2-5.2 IU/ml for xylanase) than the fungal enzyme production. In conclusion, this study demonstrated that hydrolyzed DDGS can be an alternative economical substrate for A. niger strains to produce cellulase and xylanase, respectively. The next phases of the study should further optimize the production of cellulase and xylanase in terms of growth parameters and medium components by using bench-top bioreactors.


Investigating the performances of photovoltaic modules/systems for Central Anatolia using a thermal modeling approach
Tunçel, Bilge; Akınoğlu, Bülent Gültekin; Department of Physics (2019)
Effective use and performance enhancement of the renewable energy systems are becoming increasingly important as climate change is widely recognized as one of the most crucial problems for the Earth. Turkey, a country within the solar belt, has an abundance of solar energy potential. Economical, environmental and physical investigations are needed to ensure effective utilization of this potential. In this thesis, using the meteorological parameters of the Central Anatolia and parameters of photovoltaic (PV)...
Investigation of natural gas hydrate potential of the South Caspian Sea
Mustafayeva, Zhala; Parlaktuna, Mahmut; Department of Petroleum and Natural Gas Engineering (2018)
Considering the improved technology, increase in demand on energy and limited conventional hydrocarbon resources make researchers look for new clean energy alternatives. Existence of large amount of gas hydrates in continental margins and permafrost regions shows that methane in gas hydrates may be the next clean energy supply of the world. The energy potential of gas hydrates has been encouraged researhers from all around the world to understand conditions for occurrence of gas hydrate and estimate the amo...
Investigation of alkaline pretreatment parameters on amulti-product basis for the co-production of glucose and hemicellulose based films from corn cobs
Toraman, Hilal Ezgi; Bakır Bölükbaşı, Ufuk; Özkan, Necati; Department of Chemical Engineering (2012)
There is an increasing trend in the world for using renewable sources of fuels and chemicals due to the continuous depletion of fossil fuel reserves besides the environmental issues related with the exploitation of these resources. Lignocellulosic biomass is seen as the most promising candidate to be used instead of fossil sources because of its availability, relatively low price and less competition with food and feed crops. In this study, corn cobs, a lignocellulosic agricultural waste, were subjected to ...
Investigation of Turkish lignites and biomass at high heating rates by using wire mesh apparatus
Baghirzade, Mammadbaghir; Kazanç Özerinç, Feyza; Department of Micro and Nanotechnology (2018)
Coal continues to play a significant role in energy production over the world. However, its limited procurement and enormous side effects on global warming, make governments and organizations turn towards renewable energy resources like biomass which is CO2 neutral. Prior to utilization of fuels in power plants, it is important to investigate fuel behavior at high temperatures and high heating rates, i.e., close to heating rates in industrial applications. This understanding enables engineers to design appr...
Estimation of specific flow duration curves using basin characteristics of rivers in Eastern Blacksea Basin
Yılmaz, Deniz; Şorman, Ali Ünal; Department of Civil Engineering (2011)
New and renewable energy resources are important in view of reduction of greenhouse gasses causing climate change and in eliminating of dependence on foreign sources in energy respects. Within this context, hydraulic energy is evaluated as one of the prior energy resources that should be utilized. Turkey has 26 basins and Eastern Black Sea Basin is one of the most feasible basins with a lot of small hydroelectric power plants. In the other hand, there is not enough number of discharge gauging stations in th...
Citation Formats
A. Iram, D. Çekmecelioğlu, and A. Demirci, “Screening of bacterial and fungal strains for cellulase and xylanase production using distillers’ dried grains with solubles (DDGS) as the main feedstock,” BIOMASS CONVERSION AND BIOREFINERY, vol. 11, no. 5, pp. 1955–1964, 2021, Accessed: 00, 2021. [Online]. Available: