From induction to secretion: a complicated route for cellulase production in Trichoderma reesei

The imposition of ethanol derived from biomass for blending in gasoline would make countries less dependent on current petroleum sources, which would save foreign exchange reserves, improve rural economies and provide job opportunities in a clean and safe environment. The key drivers for successful commercial ethanol production are cheap raw materials, economic pretreatment technologies, in-house cellulase production with high and efficient titers, high ethanol fermentation rates, downstream recovery of ethanol and maximum by-products utilization. Furthermore, recent developments in engineering of biomass for increased biomass, down-regulation of lignin synthesis, improved cellulase titers and re-engineering of cellulases, and process integration of the steps involved have increased the possibility of cheap bioethanol production that competes with the price of petroleum. Recently, many companies have come forward globally for bioethanol production on a large scale. It is very clear now that bioethanol will be available at the price of fossil fuels by 2010. This article intends to provide insight and perspectives on the important recent developments in bioethanol research, the commercialization status of bioethanol production, the step-wise cost incurred in the process involved, and the possible innovations that can be utilized to reduce the cost of ethanol production.

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Environmental and economic potential of rice husk use in An Giang province, Vietnam

Journal of Vietnamese Environment ◽

10.13141/jve.vol8.no3.pp206-211 ◽

2017 ◽

Vol 8 (3) ◽

pp. 206-211

Author(s):

Thi Mai Thao Pham

Keyword(s):

Power Generation ◽

Rice Husk ◽

Life Cycle Analysis ◽

Large Scale ◽

Fossil Fuels ◽

Small Scale ◽

Emission Mitigation ◽

Mitigation Potential ◽

Direct Combustion ◽

The Cost

To evaluate CO2 emission mitigation potential and cost effectiveness of rice husk utilization, Life Cycle Analysis was conducted for 9 scenarios. The results showed that, gasification is the most efficient CO2 mitigation. From cost analysis, the cost mitigation can be achieved by replacing the current fossil fuels in cooking scenarios. Among the power generation scenarios, it was found that 30MW combustion and 5MW gasification power generations were the most economically-efficient scenarios. The briquette combustion power generation appeared less cost-competitive than direct combustion, whilst the large-scale gasification scenarios and the pyrolysis scenarios give the increase in cost from the baseline. From the viewpoints of both CO2 and cost, it was indicated that the win-win scenarios can be the rice husk use for cooking, for large-scale combustion power generation, and for small-scale gasification. Để đánh giá tiềm năng giảm thiểu phát thải CO2 và hiệu quả chi phí của việc sử dụng trấu, phương pháp đánh giá vòng đời sản phẩm đã được thực hiện cho 9 kịch bản. Kết quả cho thấy, khí hóa trấu để sản xuất điện có tiềm năng giảm phát sinh khí CO2 nhiều nhất. Kết quả phân tích chi phí cho thấy việc giảm thiểu chi phí có thể đạt được khi thay thế sử dụng nhiên liệu hóa thạch trong kịch bản dùng trấu cho nấu ăn. Giữa các kịch bản về sản xuất điện, hiệu quả kinh tế cao nhất trong trường hợp đốt trực tiếp trấu để sản xuất điện ở quy mô công xuất lớn (30MW) và khí hóa ở quy mô trung bình (5MW). Trường hợp dùng củi trấu không mang lại hiệu quả kinh tế so với dùng trực tiếp trấu để phát điện. Hai trường hợp dùng trấu để sản xuất dầu sinh học và khí hóa gas công suất lớn (30MW) cho thấy chi phí tăng cao so với điều kiện biên. Kịch bản cho kết quả khả thi về hiệu quả kinh tế và giảm phát thải CO2 là dùng trấu để nấu ăn, đốt trực tiếp để phát điện công suất lớn và khí hóa công suất trung bình.

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Genetic improvement of Trichoderma reesei for large scale cellulase production

Enzyme and Microbial Technology ◽

10.1016/0141-0229(88)90012-9 ◽

1988 ◽

Vol 10 (6) ◽

pp. 341-346 ◽

Cited By ~ 161

Author(s):

Henri Durand ◽

Marc Clanet ◽

Gérard Tiraby

Keyword(s):

Trichoderma Reesei ◽

Genetic Improvement ◽

Large Scale ◽

Cellulase Production

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Preliminary Cost Estimates for Massive Hydrogen Production Using SI Process

Fourth International Topical Meeting on High Temperature Reactor Technology, Volume 2 ◽

10.1115/htr2008-58142 ◽

2008 ◽

Cited By ~ 2

Author(s):

K. J. Yang ◽

K. Y. Lee ◽

T. H. Lee

Keyword(s):

Hydrogen Production ◽

Large Scale ◽

Fossil Fuels ◽

Production Costs ◽

Scale Production ◽

Cost Estimates ◽

Production Of Hydrogen ◽

Major Factors ◽

The Cost ◽

Hydrogen Systems

As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GT-MHR and PBMR are estimated in the necessary input data on a Korean specific basis. G4-ECONS was appropriately modified to calculate the cost for hydrogen production of SI process with VHTR as a thermal energy source rather than the LUEC. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if CO2 capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of CO2. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed.

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Duckweed (Lemna minor) is a novel natural inducer of cellulase production in Trichoderma reesei

10.7287/peerj.preprints.26529 ◽

2018 ◽

Author(s):

Chen Li ◽

Jun Feng ◽

Xue Bai ◽

Shulin Chen ◽

Dongyuan Zhang ◽

...

Keyword(s):

Trichoderma Reesei ◽

Fermentation Process ◽

Lemna Minor ◽

Biomass Accumulation ◽

Cellulase Production ◽

Enzyme Hydrolysis ◽

Hydrolysis Rate ◽

Shake Flasks ◽

The Cost ◽

Rut C30

An inducer is crucial for cellulase production. In this study, duckweed was used as an inducer of cellulase production by Trichoderma reesei RUT C30. In a reaction induced by 50 g l-1 duckweed in shake flasks, the filter-paper activity (FPA) reached 6.5 FPU ml-1, a value comparable to that induced by avicel. The enzyme-hydrolysis rate induced by steam-exploded corn stalks was 54.2%, representing a 28% improvement over that induced by avicel. The duckweed starch was hydrolyzed to glucose, which was subsequently used for biomass accumulation during the fermentation process. Furthermore, to optimize control of the fermentation process, a combined substrate of avicel and duckweed was used to induce cellulase production by T. reesei RUT C30. The cellulase production and hydrolysis rates for the combined substrate, compared with avicel alone, were 39.6% and 36.7% higher, respectively. The results of this study suggest that duckweed is a good inducer of cellulase production in T. reesei, and it might aid in decreasing the cost of lignocellulosic-material hydrolysis.

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The Generation of Pollution-Free Electrical Power From Solar Energy

Journal of Engineering for Power ◽

10.1115/1.3445661 ◽

1972 ◽

Vol 94 (2) ◽

pp. 78-82 ◽

Cited By ~ 2

Author(s):

W. R. Cherry

Keyword(s):

Solar Energy ◽

Large Scale ◽

Fossil Fuels ◽

Electrical Power ◽

Terrestrial Plants ◽

Solar Arrays ◽

Social Ecological ◽

Productive Land ◽

The Cost ◽

Power Shortages

Projections of the U. S. electrical power demands over the next 30 years indicate that the U. S. could be in grave danger from power shortages, undesirable effluence, and thermal pollution. A pollution free method of converting solar energy directly into electrical power using photovoltaics on the ground shows that sunlight falling on about 1 percent of the land area of the 48 states could provide the total electrical power requirements of the U. S. in the year 1990. By utilizing and further developing some NASA technology, a new source of electrical power will become available. Such a development is attractive from conservation, social, ecological, economic, and political standpoints. While the cost of producing solar arrays by today’s methods prohibits their use for large scale terrestrial plants, the paper suggests how the cost may become acceptable, especially as conventional fuels become scarcer and more expensive. Some of the desirable reasons for developing methods to convert solar energy to electrical power are: to conserve our fossil fuels for more sophisticated uses than just burning, to reduce atmospheric pollution by 20 percent, to convert low productive land areas into high productive land areas, to make the U. S. less dependent upon foreign sources of energy, and to learn to utilize our most abundant inexhaustable natural resource.

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Duckweed (Lemna minor) is a novel natural inducer of cellulase production in Trichoderma reesei

10.7287/peerj.preprints.26529v1 ◽

2018 ◽

Author(s):

Chen Li ◽

Jun Feng ◽

Xue Bai ◽

Shulin Chen ◽

Dongyuan Zhang ◽

...

Keyword(s):

Trichoderma Reesei ◽

Fermentation Process ◽

Lemna Minor ◽

Biomass Accumulation ◽

Cellulase Production ◽

Enzyme Hydrolysis ◽

Hydrolysis Rate ◽

Shake Flasks ◽

The Cost ◽

Rut C30

An inducer is crucial for cellulase production. In this study, duckweed was used as an inducer of cellulase production by Trichoderma reesei RUT C30. In a reaction induced by 50 g l-1 duckweed in shake flasks, the filter-paper activity (FPA) reached 6.5 FPU ml-1, a value comparable to that induced by avicel. The enzyme-hydrolysis rate induced by steam-exploded corn stalks was 54.2%, representing a 28% improvement over that induced by avicel. The duckweed starch was hydrolyzed to glucose, which was subsequently used for biomass accumulation during the fermentation process. Furthermore, to optimize control of the fermentation process, a combined substrate of avicel and duckweed was used to induce cellulase production by T. reesei RUT C30. The cellulase production and hydrolysis rates for the combined substrate, compared with avicel alone, were 39.6% and 36.7% higher, respectively. The results of this study suggest that duckweed is a good inducer of cellulase production in T. reesei, and it might aid in decreasing the cost of lignocellulosic-material hydrolysis.

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Mini-Review Teknologi Carbon Capture and Utilization (CCU) Berbasis Kombinasi Proses Kimia dan Bioproses

EKUILIBRIUM Journal of Chemical Engineering ◽

10.20961/equilibrium.v4i2.47908 ◽

2021 ◽

Vol 4 (2) ◽

Author(s):

Anisa Azzahra Isya ◽

Kezia Rhesa Arman ◽

Joko Wintoko

Keyword(s):

Carbon Capture ◽

Large Scale ◽

Fossil Fuels ◽

Raw Material ◽

Stable Form ◽

Absorption Process ◽

Chemical Absorption ◽

Carbon Capture And Utilization ◽

Energy Needs ◽

The Cost

Currently, energy needs still rely on fossil fuels. On the other hand, CO2 emissions resulting from burning fossil fuels continue to increase and contribute as a greenhouse gas in the atmosphere. Global warming is a threat to the future of life. One of the countermeasures is by developing Carbon, Capture, and Utilization (CCU) technology based on a chemical absorption process to capture CO2 gas from combustion. The captured CO2 is then stored in a stable form so it will not be released into the atmosphere or used as raw material for the chemical industry. The main obstacle to implementing CCU technology on a large scale is the cost involved. Meanwhile, the revenue generated is relatively low. In CCU technology based on this chemical absorption process, chemicals as absorbents need to be regenerated and the CO2 is separated for storage or use. However, this regeneration requires a relatively high cost. Several studies have attempted to perform this regeneration with micro-algae-based bioprocesses. Micro-algae can take energy from sunlight which is abundant in tropical areas such as Indonesia. In addition, several types of micro algae have the potential to be used as food and other utilizations. This review will discuss the results of recent research on suitable chemicals for the absorption of CO2 from flue gas, its regeneration method using micro-algae, usable micro-algae species, and the potential for micro-algae utilization.

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Energy After COVID

Current History ◽

10.1525/curh.2020.119.820.317 ◽

2020 ◽

Vol 119 (820) ◽

pp. 317-322

Author(s):

Michael T. Klare

Keyword(s):

Renewable Energy ◽

Electric Vehicles ◽

Fossil Fuels ◽

Fossil Fuel ◽

White Collar ◽

Peak Oil ◽

Business Travel ◽

Reduce Energy Consumption ◽

The Cost ◽

Energy Companies

By transforming patterns of travel and work around the world, the COVID-19 pandemic is accelerating the transition to renewable energy and the decline of fossil fuels. Lockdowns brought car commuting and plane travel to a near halt, and the mass experiment in which white-collar employees have been working from home may permanently reduce energy consumption for business travel. Renewable energy and electric vehicles were already gaining market share before the pandemic. Under pressure from investors, major energy companies have started writing off fossil fuel reserves as stranded assets that are no longer worth the cost of extracting. These shifts may indicate that “peak oil demand” has arrived earlier than expected.

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