scholarly journals Genetic engineering, a hope for sustainable biofuel production: review

2014 ◽  
Vol 3 (2) ◽  
pp. 311-323 ◽  
Author(s):  
Sudip Paudel ◽  
Michael A Menze
Keyword(s):  
Genetic Engineering ◽  
Fossil Fuels ◽  
Genetically Modified Organisms ◽  
Lipid Production ◽  
Genetically Engineered ◽  
Raw Material ◽  
Biofuel Production ◽  
Wild Type ◽  
Environment Friendly ◽  
Genetically Engineered Organisms

The use of recently developed genetic engineering tools in combination with organisms that have the potential to produce precursors for the production of biodiesel, promises a sustainable and environment friendly energy source. Enhanced lipid production in wild type and/or genetically engineered organisms can offer sufficient raw material for industrial transesterification of plant-based triglycerides. Bio-diesel, produced with the help of genetically modified organisms, might be one of the best alternatives to fossil fuels and to mitigate various environmental hazards. DOI: http://dx.doi.org/10.3126/ije.v3i2.10644 International Journal of the Environment Vol.3(2) 2014: 311-323

scholarly journals The Use of Urea and Kelp Waste Extract is A Promising Strategy for Maximizing the Biomass Productivity and Lipid Content in Chlorella sorokiniana

Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 463 ◽  
Author(s):  
Ali Nawaz Kumbhar ◽  
Meilin He ◽  
Abdul Razzaque Rajper ◽  
Khalil Ahmed Memon ◽  
Muhammad Rizwan ◽  
...  
Keyword(s):  
Lipid Content ◽  
Fossil Fuels ◽  
Fossil Fuel ◽  
Lipid Production ◽  
Total Lipid Content ◽  
Biomass Productivity ◽  
Chlorella Sorokiniana ◽  
Biofuel Production ◽  
Promising Strategy ◽  
Waste Extract

The decline in fossil fuel reserves has forced researchers to seek out alternatives to fossil fuels. Microalgae are considered to be a promising feedstock for sustainable biofuel production. Previous studies have shown that urea is an important nitrogen source for cell growth and the lipid production of microalgae. The present study investigated the effect of different concentrations of urea combined with kelp waste extract on the biomass and lipid content of Chlorella sorokiniana. The results revealed that the highest cell density, 20.36 × 107 cells−1, and maximal dry biomass, 1.70 g/L, were achieved in the presence of 0.5 g/L of urea combined with 8% kelp waste extract. Similarly, the maximum chlorophyll a, b and beta carotenoid were 10.36 mg/L, 7.05, and 3.01 mg/L, respectively. The highest quantity of carbohydrate content, 290.51 µg/mL, was achieved in the presence of 0.2 g/L of urea and 8% kelp waste extract. The highest fluorescence intensity, 40.05 × 107 cells−1, and maximum total lipid content (30%) were achieved in the presence of 0.1 g/L of urea and 8% kelp waste extract. The current study suggests that the combination of urea and kelp waste extract is the best strategy to enhance the biomass and lipid content in Chlorella sorokiniana.

scholarly journals Biomass and lipid induction strategies in microalgae for biofuel production and other applications

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Hossein Alishah Aratboni ◽  
Nahid Rafiei ◽  
Raul Garcia-Granados ◽  
Abbas Alemzadeh ◽  
José Rubén Morones-Ramírez
Keyword(s):  
Lipid Content ◽  
Large Scale ◽  
Fossil Fuels ◽  
Low Cost ◽  
Lipid Production ◽  
Arable Land ◽  
Economic Cost ◽  
Biofuel Production ◽  
Scale Production ◽  
Microalgae Biomass

Abstract The use of fossil fuels has been strongly related to critical problems currently affecting society, such as: global warming, global greenhouse effects and pollution. These problems have affected the homeostasis of living organisms worldwide at an alarming rate. Due to this, it is imperative to look for alternatives to the use of fossil fuels and one of the relevant substitutes are biofuels. There are different types of biofuels (categories and generations) that have been previously explored, but recently, the use of microalgae has been strongly considered for the production of biofuels since they present a series of advantages over other biofuel production sources: (a) they don’t need arable land to grow and therefore do not compete with food crops (like biofuels produced from corn, sugar cane and other plants) and; (b) they exhibit rapid biomass production containing high oil contents, at least 15 to 20 times higher than land based oleaginous crops. Hence, these unicellular photosynthetic microorganisms have received great attention from researches to use them in the large-scale production of biofuels. However, one disadvantage of using microalgae is the high economic cost due to the low-yields of lipid content in the microalgae biomass. Thus, development of different methods to enhance microalgae biomass, as well as lipid content in the microalgae cells, would lead to the development of a sustainable low-cost process to produce biofuels. Within the last 10 years, many studies have reported different methods and strategies to induce lipid production to obtain higher lipid accumulation in the biomass of microalgae cells; however, there is not a comprehensive review in the literature that highlights, compares and discusses these strategies. Here, we review these strategies which include modulating light intensity in cultures, controlling and varying CO2 levels and temperature, inducing nutrient starvation in the culture, the implementation of stress by incorporating heavy metal or inducing a high salinity condition, and the use of metabolic and genetic engineering techniques coupled with nanotechnology.

scholarly journals Genetic engineering of microalgae lipid biosynthesis for sustainable biodiesel production

2021 ◽  
Vol 11 (3) ◽  
pp. 072-077
Author(s):  
Siti Zulaiha
Keyword(s):  
Genetic Engineering ◽  
Metabolic Pathways ◽  
Alternative Energy ◽  
Fossil Fuels ◽  
Lipid Production ◽  
High Growth ◽  
Lipid Biosynthesis ◽  
Production Costs ◽  
Biodiesel Production ◽  
Promising Alternative

Biofuel is one of the most promising alternative energy sources for reducing human reliance on fossil fuels. Microalgae has recently emerged as the most promising biofuel source. However, biofuels from microalgae are still not feasible to replace fossil fuels because of their high production costs, therefore, it is necessary to pick microalgae species with high growth rates and lipid content. Overexpression of lipid biosynthesis enzymes and inhibition of competitive metabolic pathways are two genetic engineering strategies that can be developed to assess microalgae lipid production. Malate and multienzyme enzymes (GPAT, LPAAT and DGAT) can be overexpressed in microalgae to boost lipid production. The strategy of blocking competitive metabolic pathways can be carried out through suppression of starch metabolism and lipid catabolism. The strategy of blocking competitive metabolic pathways has been carried out in several microalgae and is effective for enhancing lipid biosynthesis. Several mutations that block both the starch metabolic and lipid catabolic pathways can result in increased levels of microalgal lipid accumulation.

scholarly journals Efficient Production of l-Lactic Acid from Xylose by Pichia stipitis

2006 ◽  
Vol 73 (1) ◽  
pp. 117-123 ◽  
Author(s):  
Marja Ilmén ◽  
Kari Koivuranta ◽  
Laura Ruohonen ◽  
Pirkko Suominen ◽  
Merja Penttilä
Keyword(s):  
Lactate Production ◽  
Pichia Stipitis ◽  
Genetically Engineered ◽  
Lactobacillus Helveticus ◽  
Raw Material ◽  
Industrial Biotechnology ◽  
Efficient Production ◽  
Wild Type ◽  
Microbial Conversion ◽  
Wild Type Level

ABSTRACT Microbial conversion of renewable raw materials to useful products is an important objective in industrial biotechnology. Pichia stipitis, a yeast that naturally ferments xylose, was genetically engineered for l-(+)-lactate production. We constructed a P. stipitis strain that expressed the l-lactate dehydrogenase (LDH) from Lactobacillus helveticus under the control of the P. stipitis fermentative ADH1 promoter. Xylose, glucose, or a mixture of the two sugars was used as the carbon source for lactate production. The constructed P. stipitis strain produced a higher level of lactate and a higher yield on xylose than on glucose. Lactate accumulated as the main product in xylose-containing medium, with 58 g/liter lactate produced from 100 g/liter xylose. Relatively efficient lactate production also occurred on glucose medium, with 41 g/liter lactate produced from 94 g/liter glucose. In the presence of both sugars, xylose and glucose were consumed simultaneously and converted predominantly to lactate. Lactate was produced at the expense of ethanol, whose production decreased to ∼15 to 30% of the wild-type level on xylose-containing medium and to 70 to 80% of the wild-type level on glucose-containing medium. Thus, LDH competed efficiently with the ethanol pathway for pyruvate, even though the pathway from pyruvate to ethanol was intact. Our results show, for the first time, that lactate production from xylose by a yeast species is feasible and efficient. This is encouraging for further development of yeast-based bioprocesses to produce lactate from lignocellulosic raw material.

scholarly journals THE PROSPECTS, IMPACTS, AND RESEARCH CHALLENGES OF ENHANCED CELLULOSIC ETHANOL PRODUCTION: A REVIEW

2016 ◽  
Vol 36 (1) ◽  
pp. 267-275
Author(s):  
SL Ezeoha ◽  
CN Anyanwu ◽  
JN Nwakaire
Keyword(s):  
Ethanol Production ◽  
Cellulosic Ethanol ◽  
Fossil Fuels ◽  
Developing Economies ◽  
Cost Effective ◽  
Genetically Engineered ◽  
Biofuel Production ◽  
Production Processes ◽  
Research Challenges ◽  
Thermochemical Processes

The benefits and impacts of enhanced cellulosic ethanol (CE) production, the major features of existing production processes, and some current research challenges of major pretreatment processes are presented. The prospects of enhanced CE production, especially in developing economies like Nigeria are highlighted. We conclude that in order to reap the promising prospects and conquer the challenges and negative impacts of enhanced CE production, current researches for production of cellulosic ethanol must be focused on the development of processes that are capable of liberating and fermenting lignocellulose into bioethanol at faster rates, higher yields, and overall technical and economic efficiency. These researches should concentrate on the development of cheaper enzymes, genetically engineered microorganisms, and cost-effective thermochemical processes in order to accomplish the much-needed breakthrough in cellulosic biofuel production. Properly targeted innovative researches on cellulosic ethanol production processes are the sure route to effective reduction of global dependence on nonrenewable fossil fuels. The needed research breakthroughs will obviously be based on innovative integration of processes rather than on the improvement of the well-known individual processes of bioethanol production. http://dx.doi.org/10.4314/njt.v36i1.32

How to keep out what we don't want: an assessment of `Sozialverträglichkeit' under the Austrian Genetic Engineering Act

1997 ◽  
Vol 6 (4) ◽  
pp. 301-327 ◽  
Author(s):  
Franz Seifert ◽  
Helge Torgersen
Keyword(s):  
Decision Making ◽  
Genetic Engineering ◽  
Fundamental Problem ◽  
National Level ◽  
Predictive Ability ◽  
Complex Problem ◽  
Genetically Engineered ◽  
Risk Society ◽  
Decision Making Process ◽  
Genetically Engineered Organisms

National regulations for new science and engineering projects are often drawn up on foundations that refer to the current `state of the art'. However, this approach suffers from the fundamental problem, among others, that science progresses quickly, and models for the development of science have only limited predictive ability. Assessing the risk associated with a project therefore becomes a complex problem; and so non-scientific criteria can not be excluded from the decision-making process. An example of such non-technical criteria can be found in Austrian regulations on genetic engineering where: `products containing or consisting of genetically engineered organisms must not create any “ Soziale Unverträglichkeit” [social unsustainability], no `unbalanced burden on society or social groups' that is unacceptable for economic, social or moral reasons.' The aim of this paper is to investigate the implications of this provision. The paper begins with a discussion of the fundamental issues of regulating genetic engineering at a national level, then examines the evolution of the Austrian Genetic Engineering Act, and critically assesses the term ` Sozialverträglichkeit'. Having examined various mechanisms whereby non-scientific criteria can be included in the decision-making process, the paper argues that Sozialverträglichkeit can be interpreted as a constructive answer to the problems of a risk society.

scholarly journals Pengaruh pemberian variasi pH terhadap produksi trigliserida total dan komposisi asam lemak dari chlorella vulgaris air tawar

2019 ◽  
Vol 10 (2) ◽  
pp. 66-74
Author(s):  
Rahmadani Wulandari
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Chlorella Vulgaris ◽  
Culture Medium ◽  
Lipid Production ◽  
Raw Material ◽  
Biofuel Production ◽  
High Lipid ◽  
Culture Growth

Chlorella vulgaris is a microalgae that has high lipid content and potential as raw material for biofuel production. This study aims are to determine the effect of pH on growth, lipid production and fatty acid composition of C. vulgaris by using Growmore 32-10-10 fertilizer as a culture medium. Microalgae were cultured in medium Growmore 32-10-10 for 10 days. Afterward, pH of medium was varied into pH 5, 7, 8.2 and 9 and continued cultivate for 3 days. C. vulgaris cultured at pH 8.2 which is a control pH reached optimum growths. The GC-MS analysis for lipid productivity of C. vulgaris was 0.5020 g/L/day and 0.2902 g/L/day for microalgae grew at pH 8.2 and 9, respectively. Cultures at pH 8.2 and 9 produce methyl hexadecanoate, methyl 9-octadecanoate, methyl octadecanoate, methyl 9,12-octadecadienoate, methyl 9,11-octadecadienoate. Additional fatty acid methyl nonadecanoate was also found in C. vulgaris grew at pH 9. The low and high pH stress of C. vulgaris culture medium did not affect culture growth but altered lipid production and fatty acid composition. 

scholarly journals Advanced Metabolic Engineering Approaches and Renewable Energy to Improve Environmental Benefits of Algal Biofuels: LCA of Large-scale Biobutanol Production with Cyanobacteria Synechocystis PCC6803

2021 ◽  
Author(s):  
Daniela Villacreses-Freire ◽  
Franziska Ketzer ◽  
Christine Rösch
Keyword(s):  
Genetic Engineering ◽  
Large Scale ◽  
Genetically Engineered ◽  
Environmental Benefits ◽  
Biofuel Production ◽  
Scale Production ◽  
Renewable Electricity ◽  
Synechocystis Pcc6803 ◽  
Cell Factories ◽  
Green Cell

AbstractWith modern genetic engineering tools, microorganisms can become resilient green cell factories to produce sustainable biofuels directly. Compared to non-engineered algae and cyanobacteria, the photon conversion efficiency can be significantly increased. Furthermore, simplified harvesting processes are feasible since the novel microorganisms are excreting the biofuels or their precursors continuously and directly into the cultivation media. Along with higher productivity and direct product harvesting, it is expected that environmental benefits can be achieved, especially for climate protection. A life cycle assessment (LCA) for biobutanol production with the genetically engineered cyanobacteria Synechocystis PCC6803 is performed to test this hypothesis. A prospective and upscaled approach was applied to assess the environmental impacts at large-scale production (20 ha plant) for better comparability with conventional butanol production. The LCA results show that the engineering of microorganisms can improve the environmental impact, mainly due to the higher productivity compared to non-engineered cyanobacteria. However, the nevertheless high electricity demand required for the cultivation and harvesting process overcompensates this benefit. According to the scenario calculations, a more favourable climate gas balance can be achieved if renewable electricity is used. Then, greenhouse gas emissions are reduced to 3.1 kg CO2 eq/kg biobutanol, corresponding to 20% more than the fossil reference: (2.45 kg CO2 eq./kg 1-butanol). The results indicate the importance of genetic engineering and the energy transition towards renewable electricity supply to take full advantage of the environmental potential of microorganisms as future green cell factories for sustainable biofuel production. Besides, the necessity of developing different scenarios for perspective and upscaled LCA for a fairer comparison with mature reference technologies is demonstrated.

scholarly journals Pengaruh Pemberian Variasi pH Terhadap Produksi Trigliserida Total dan Komposisi Asam Lemak dari Chlorella Vulgaris Air Tawar

2019 ◽  
Vol 10 (2) ◽  
pp. 66-74
Author(s):  
Rahmadani Wulandari ◽  
Abdi Dharma ◽  
Syafrizayanti Syafrizayanti
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Chlorella Vulgaris ◽  
Culture Medium ◽  
Lipid Production ◽  
Raw Material ◽  
Biofuel Production ◽  
High Lipid ◽  
Culture Growth

Chlorella vulgaris is a microalgae that has high lipid content and potential as raw material for biofuel production. This study aims are to determine the effect of pH on growth, lipid production and fatty acid composition of C. vulgaris by using Growmore 32-10-10 fertilizer as a culture medium. Microalgae were cultured in medium Growmore 32-10-10 for 10 days. Afterward, pH of medium was varied into pH 5, 7, 8.2 and 9 and continued cultivate for 3 days. C. vulgaris cultured at pH 8.2 which is a control pH reached optimum growths. The GC-MS analysis for lipid productivity of C. vulgaris was 0.5020 g/L/day and 0.2902 g/L/day for microalgae grew at pH 8.2 and 9, respectively. Cultures at pH 8.2 and 9 produce methyl hexadecanoate, methyl 9-octadecanoate, methyl octadecanoate, methyl 9,12-octadecadienoate, methyl 9,11-octadecadienoate. Additional fatty acid methyl nonadecanoate was also found in C. vulgaris grew at pH 9. The low and high pH stress of C. vulgaris culture medium did not affect culture growth but altered lipid production and fatty acid composition.

scholarly journals THIRD GENERATION BIODIESEL: A POTENTIAL SUSTAINABLE ENERGY SOURCE FROM MICROALGAE

2020 ◽  
pp. 144-149
Author(s):  
Sheetal Gadhiya ◽  
Anjali Shukla ◽  
Nainesh Modi
Keyword(s):  
Fossil Fuels ◽  
Production Efficiency ◽  
Lipid Production ◽  
Biofuel Production ◽  
Net Energy ◽  
Third Generation ◽  
High Lipid ◽  
Realistic Option ◽  
Generation Biofuel ◽  
Net Energy Gain

Biofuel production from renewable sources is generally considered to be one of the most sustainable alternatives to fossil fuels, and a viable means of sustainability for the environment and the economy. Because of their rapid growth rate, CO2 fixation ability and high lipid production efficiency, microalgae are currently being promoted as an ideal third generation biofuel feedstock; they also do not compete with food or feed crops, and can be grown on non-arable soil. Biofuels can be generated in combination with flue gas CO2 mitigation, wastewater treatment and high value production. Seawater can be used to achieve microalgal farming employing microalgal organisms as the source. To be a realistic option, a biofuel must have few features such as net energy gain, eco-friendly, economically efficient and implementable in large volumes without affecting resources demand. In this study we present an overview of the use of microalgae for the production of biodiesel, including its cultivation, harvesting, and processing. Further it is suggested that biodiesel is an effective renewable substitute for petroleum diesel. KEYWORDS: Biodiesel, Biofuels, Carbon emission, Microalgae

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