Enhanced Biofuel Production from High-Concentration Bioethanol Wastewater by a Newly Isolated Heterotrophic Microalga, Chlorella vulgaris LAM-Q

Palm oil mill effluent (POME), a pollutant produced by the palm oil industry, was treated by the Vetiver system technology (VST). This technology was applied for the first time to treat POME in order to decrease biochemical oxygen demand (BOD) and chemical oxygen demand (COD). In this study, two different concentrations of POME (low and high) were treated with Vetiver plants for 2 weeks. The results showed that Vetiver was able to reduce the BOD up to 90% in low concentration POME and 60% in high concentration POME, while control sets (without plant) only was able to reduce 15% of BOD. The COD reduction was 94% in low concentration POME and 39% in high concentration POME, while control just shows reduction of 12%. Morphologically, maximum root and shoot lengths were 70 cm, the number of tillers and leaves was 344 and 86, and biomass production was 4.1 kg m−2. These results showed that VST was effective in reducing BOD and COD in POME. The treatment in low concentration was superior to the high concentration. Furthermore, biomass of plant can be considered as a promising raw material for biofuel production while high amount of biomass was generated in low concentration of POME.

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Microwave drying characteristics of microalgae (Chlorella vulgaris) for biofuel production

Clean Technologies and Environmental Policy ◽

10.1007/s10098-016-1169-0 ◽

2016 ◽

Vol 18 (8) ◽

pp. 2441-2451 ◽

Cited By ~ 18

Author(s):

Al Rey C. Villagracia ◽

Andres Philip Mayol ◽

Aristotle T. Ubando ◽

Jose Bienvenido Manuel M. Biona ◽

Nelson B. Arboleda ◽

...

Keyword(s):

Chlorella Vulgaris ◽

Biofuel Production ◽

Microwave Drying ◽

Drying Characteristics

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Effect of salt type and concentration on the growth and lipid content of Chlorella vulgaris in synthetic saline wastewater for biofuel production

Bioresource Technology ◽

10.1016/j.biortech.2017.06.081 ◽

2017 ◽

Vol 243 ◽

pp. 147-153 ◽

Cited By ~ 40

Author(s):

Jared Church ◽

Jae-Hoon Hwang ◽

Keug-Tae Kim ◽

Rebecca McLean ◽

You-Kwan Oh ◽

...

Keyword(s):

Chlorella Vulgaris ◽

Lipid Content ◽

Biofuel Production ◽

Saline Wastewater

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Optimizing Chlorella Vulgaris And Anabaena Variabilis Growth Conditions For Use As Biofuel Feedstock

Journal of the Asiatic Society of Bangladesh Science ◽

10.3329/jasbs.v42i2.46222 ◽

2016 ◽

Vol 42 (2) ◽

pp. 191-200

Author(s):

NJ Tarin ◽

NM Ali ◽

AS Chamon ◽

MN Mondol ◽

MM Rahman ◽

...

Keyword(s):

Light Intensity ◽

Chlorella Vulgaris ◽

Vitamin B1 ◽

Growth Conditions ◽

Anabaena Variabilis ◽

Biofuel Production ◽

Optimum Growth ◽

Biofuel Feedstock ◽

Isolation And Characterization ◽

Physical And Chemical

Isolation and characterization of Chlorella vulgaris (green alga) and Anabaena variabilis (cyanobacterium) were made from natural and artificial water bodies of Dhaka University and Khulna, Bangladesh from March through December 2014 using modified Chu-10D medium to determine their potential as feedstock for biofuel production. Optimum growth measured as total chlorophyll and optical density under varying physical and chemical environments was determined. The optimum growth for C. vulgaris was obtained at pH 6.5 under light intensity of 110 μE m-2 s-1 and one and a half times the concentration of the Chu-10D. Compared to this, the optimum growth for A. variabilis was obtained at 7.0 pH, 90 μE m-2 s-1 light intensity and normal Chu 10D. Both organisms were grown at 25o C temperature. Aeration of medium showed a significant positive growth for both the isolates. Supplementation of medium with vitamin B1, B6, B7 and B12 would yield higher biomass of C. vulgaris as biofuel feedstock. Vitamins were not required for growing A. variabilis. Asiat. Soc. Bangladesh, Sci. 42(2): 191-200, December 2016

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Analysis of the optimum pH and salinity conditions for the cultivation and biomass production of Chlorella vulgaris from cassava waste

International Journal of Science and Research Archive ◽

10.30574/ijsra.2021.4.1.0192 ◽

2021 ◽

Vol 4 (1) ◽

pp. 171-178

Author(s):

Uchenna Nwanodi Nwankwo ◽

Obioma Kenechukwu Agwa

Keyword(s):

Biomass Production ◽

Chlorella Vulgaris ◽

Alternative Energy ◽

Fossil Fuels ◽

Optimal Growth ◽

Biofuel Production ◽

Minimal Growth ◽

Transportation Fuels ◽

Optimum Ph ◽

Cassava Waste

Biofuel serves as an alternative energy to the common fossil fuels currently in use globally and are drawing increasing attention worldwide as substitutes for petroleum-derived transportation fuels to help address challenges associated with petroleum derived fuels. Third generation biofuels, also termed advanced biofuels, are produced from fast growing microalgae and are potential replacements for conventional fuels. The growth and biomass production of these microalgae is dependent on the conditions they are cultivated such as pH and Salinity. Cassava waste mixtures were cultivated on Chlorella vulgaris stock culture at different concentration ratio at ambient temperature, natural light and dark conditions at 670nm absorbance for 14 days. Optimum growth was obtained at 160:40 for cassava peel water to cassava waste water CP:CW. pH variations 6.0, 6.5, 7.0, 7.5, 8.0, 8.5 and 9.0 were checked to determine the optimum pH for the growth and biomass production of Chlorella vulgaris on the optimum cassava waste mixture concentration. It revealed that at pH 6.5, optimal growth and biomass production was achieved, minimal growth was observed at pH 8.0 while minimal biomass was produced at pH 9.0. Salinity variations of 5, 10, 15, 20, 25, 30, 35 and 40 mg/l were used to determine the growth response and biomass production of Chlorella vulgaris. It revealed that salinity variation at 10ppm will be necessary for highest growth on the cassava waste as well as in biomass production. The use of optimal pH and salinity can significantly increase biomass production thus enhancing biofuel production.

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Improvement of lab-scale production of microalgal carbohydrates for biofuel production

CT&F - Ciencia Tecnología y Futuro ◽

10.29047/01225383.209 ◽

2012 ◽

Vol 5 (1) ◽

pp. 103-116 ◽

Cited By ~ 1

Author(s):

Silvia-Juliana Jerez-Mogollón ◽

Laura-Viviana Rueda-Quiñonez ◽

Laura-Yulexi Alfonso-Velazco ◽

Andrés-Fernando Barajas-Solano ◽

Crisóstomo Barajas-Ferreira ◽

...

Keyword(s):

Chlorella Vulgaris ◽

Biomass Productivity ◽

Biofuel Production ◽

Scale Production ◽

Initial Concentration ◽

The Third ◽

Carbon Nitrogen Ratio ◽

Nitrogen Ratio ◽

Do So

This work studied the improvement of biomass and carbohydrate (glucose and xylose) lab–scale productivity in Chlorella vulgaris UTEX 1803 through the use of the carbon/nitrogen ratio. In order to do so, mixotrophic cultures were made by the modification of initial concentration of CH3COONa (5, 10 and 20 mM) and NaNO3 (0.97, 1.94 and 2.94 mM). All treatments were maintained at 23 ± 1ºC, with light/dark cycles of 12h : 12h for 5 days.It was found that in addition to the carbon/nitrogen ratio, time also influences the concentration of biomass and carbohydrates. The treatment containing 10 mM acetate: 1.94 mM nitrate, reached a concentration of 0.79 g/L of biomass, 76.9 μg/mL of xylose and 73.7 μg/mL of glucose in the fifth day. However, the treatmentcontaining 20 mM acetate: 0.97 mM nitrate produced 1.04 g/L of biomass, 78.9 μg/mL of xylose and 77.2 μg/mL of glucose in the third day, while in the same day the treatment containing 0 mM acetate: 2.94 mM nitrate, produced 0.55 g/L of biomass, 40.2 μg/mL of xylose and 31.3 μg/mL of glucose.The use of carbon/nitrogen ratios improved biomass productivity (from 0.55 to 1.04 g/L) as well as xylose (from 40.2 to 78.9 μg/mL) and glucose (from 31.3 to 77.2 μg/mL) concentration, representing an improvement of up to two times the production of both biomass and carbohydrates in only 3 days of culture.

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Combined resistance to oxidative stress and reduced antenna size enhance light-to-biomass conversion efficiency in Chlorella vulgaris cultures

Biotechnology for Biofuels ◽

10.1186/s13068-019-1566-9 ◽

2019 ◽

Vol 12 (1) ◽

Cited By ~ 11

Author(s):

Luca Dall’Osto ◽

Stefano Cazzaniga ◽

Zeno Guardini ◽

Simone Barera ◽

Manuel Benedetti ◽

...

Keyword(s):

Chlorella Vulgaris ◽

Fossil Fuels ◽

Biomass Conversion ◽

Carbon Assimilation ◽

Phenotypic Selection ◽

Biofuel Production ◽

Carbon Assimilation Rate ◽

Photon Conversion ◽

Pale Green ◽

Fast Growth Rate

Abstract Background Microalgae are efficient producers of lipid-rich biomass, making them a key component in developing a sustainable energy source, and an alternative to fossil fuels. Chlorella species are of special interest because of their fast growth rate in photobioreactors. However, biological constraints still cast a significant gap between the high cost of biofuel and cheap oil, thus hampering perspective of producing CO2-neutral biofuels. A key issue is the inefficient use of light caused by its uneven distribution in the culture that generates photoinhibition of the surface-exposed cells and darkening of the inner layers. Efficient biofuel production, thus, requires domestication, including traits which reduce optical density of cultures and enhance photoprotection. Results We applied two steps of mutagenesis and phenotypic selection to the microalga Chlorella vulgaris. First, a pale-green mutant (PG-14) was selected, with a 50% reduction of both chlorophyll content per cell and LHCII complement per PSII, with respect to WT. PG-14 showed a 30% increased photon conversion into biomass efficiency vs. WT. A second step of mutagenesis of PG-14, followed by selection for higher tolerance to Rose Bengal, led to the isolation of pale-green genotypes, exhibiting higher resistance to singlet oxygen (strains SOR). Growth in photobioreactors under high light conditions showed an enhanced biomass production of SOR strains with respect to PG-14. When compared to WT strain, biomass yield of the pale green + sor genotype was enhanced by 68%. Conclusions Domestication of microalgae like Chlorella vulgaris, by optimizing both light distribution and ROS resistance, yielded an enhanced carbon assimilation rate in photobioreactor.

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Isolation and characterization of Chlorella sp. mutants with enhanced thermo- and CO2 tolerances for CO2 sequestration and utilization of flue gases

Biotechnology for Biofuels ◽

10.1186/s13068-019-1590-9 ◽

2019 ◽

Vol 12 (1) ◽

Cited By ~ 4

Author(s):

Hsiang-Hui Chou ◽

Hsiang-Yen Su ◽

Xiang-Di Song ◽

Te-Jin Chow ◽

Chun-Yen Chen ◽

...

Keyword(s):

High Temperature ◽

Chlorella Vulgaris ◽

Flue Gas ◽

Biomass Productivity ◽

Wild Type ◽

High Concentration ◽

Industrial Plants ◽

Chlorella Sp ◽

Isolation And Characterization ◽

Gas Removal

Abstract Background The increasing emission of flue gas from industrial plants contributes to environmental pollution, global warming, and climate change. Microalgae have been considered excellent biological materials for flue gas removal, particularly CO2 mitigation. However, tolerance to high temperatures is also critical for outdoor microalgal mass cultivation. Therefore, flue gas- and thermo-tolerant mutants of Chlorella vulgaris ESP-31 were generated and characterized for their ability to grow under various conditions. Results In this study, we obtained two CO2- and thermo-tolerant mutants of Chlorella vulgaris ESP-31, namely, 283 and 359, with enhanced CO2 tolerance and thermo-tolerance by using N-methyl-N-nitro-N-nitrosoguanidine (NTG) mutagenesis followed by screening at high temperature and under high CO2 conditions with the w-zipper pouch selection method. The two mutants exhibited higher photosynthetic activity and biomass productivity than that of the ESP-31 wild type. More importantly, the mutants were able to grow at high temperature (40 °C) and a high concentration of simulated flue gas (25% CO2, 80–90 ppm SO2, 90–100 ppm NO) and showed higher carbohydrate and lipid contents than did the ESP-31 wild type. Conclusions The two thermo- and flue gas-tolerant mutants of Chlorella vulgaris ESP-31 were useful for CO2 mitigation from flue gas under heated conditions and for the production of carbohydrates and biodiesel directly using CO2 from flue gas.

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