Alkaline Pre-Treatment of Gelidium Latifolium and Caulerpa Racemosa for Bioethanol Production

With decades of studies on cellulose bioconversion, cellulases have been playing an important role in producing fermentable sugars from lignocellulosic biomass. Copious microorganisms that are able to degrade cellulose have been isolated and identified. The present study has been undertaken to isolate and screen the cellulase producing bacteria from soils of agrowaste field. Cellulase production has been qualitatively analyzed in carboxy methylcellulose (CMC) agar medium after congo red staining and NaCl treatment by interpretation with zones around the potent colonies. Out of the seven isolates, only two showed cellulase production. The morphogical and molecular characterization revealed its identity as Escherichia coli and Staphylococcus aureus. The potential of organisms for bioethanol production has been investigated using two substrates, namely, paper and leaves by subjecting with a pre-treatment process using acid hydrolysis to remove lignin which acts as physical barrier to cellulolytic enzymes. Ethanolic fermentation was done using Saccharomyces cerevisiae for 24-48 h and then the bioethanol produced was qualitatively proved by iodoform assay. These finding proves that ethanol can be made from the agricultural waste and the process is recommended as a means of generating wealth from waste.

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Enzymatic saccharification of agar waste from Gracilaria verrucosa and Gelidium latifolium for bioethanol production

Journal of Applied Phycology ◽

10.1007/s10811-017-1205-4 ◽

2017 ◽

Vol 29 (6) ◽

pp. 3201-3209 ◽

Cited By ~ 10

Author(s):

Maria Dyah Nur Meinita ◽

Bintang Marhaeni ◽

Yong-Ki Hong ◽

Gwi-Taek Jeong

Keyword(s):

Enzymatic Saccharification ◽

Gracilaria Verrucosa ◽

Bioethanol Production ◽

Gelidium Latifolium

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Comparison of Conventional and Novel Pre-treatment Methods for Bioethanol Production from Fruit and Vegetable Wastes

Chemical and Biochemical Engineering Quarterly ◽

10.15255/cabeq.2019.1738 ◽

2020 ◽

Vol 33 (4) ◽

pp. 471-483

Author(s):

Tugba Keskin

Keyword(s):

Saccharomyces Cerevisiae ◽

The Other ◽

Yeast Fermentation ◽

Bioethanol Production ◽

Fruit And Vegetable ◽

Bacterial Fermentation ◽

Waste Gas ◽

Clostridium Ljungdahlii ◽

Vegetable Wastes ◽

Pre Treatment

In this study, novel and conventional techniques for the production of bioethanol from fruit and vegetable wastes (FVWs) by yeast and bacterial fermentation were investigated experimentally. Different pretreatment techniques (acid, heat, acid/heat, and microwave) for yeast fermentation were compared. Maximum ethanol concentrations of 11.7 and 11.8 g L–1 were observed from acid/heat and microwave pretreatment, respectively, by using Saccharomyces cerevisiae. On the other hand, biochar production from FVWs and syngas fermentation from the waste gas of this process were integrated. From waste gas with 12 % CO content, 5.5 g L–1 and 2.5 g L–1 ethanol production was observed by using anaerobic mixed culture and Clostridium ljungdahlii, respectively. The overall results emphasize the potential of bioethanol production from FVWs by economically feasible and environmentally friendly methods.

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Study of wheat straw delignification in a rotary-pulsation apparatus

Acta periodica technologica ◽

10.2298/apt2051103s ◽

2020 ◽

pp. 103-110

Author(s):

Larysa Sablii ◽

Oleksandr Obodovych ◽

Vitalii Sydorenko ◽

Tamila Sheyko

Keyword(s):

Wheat Straw ◽

Production Technology ◽

Raw Materials ◽

Hydrolytic Enzymes ◽

Bioethanol Production ◽

Second Generation Bioethanol ◽

Pulsation Apparatus ◽

Rotary Pulsation Apparatus ◽

Solid Water ◽

Pre Treatment

This paper presents the results of studies of isolation lignin and hemicelluloses efficiency during the pre-treatment of wheat straw for hydrolysis in a rotary-pulsation apparatus. The pre-treatment of lignocellulosic raw materials for hydrolysis is a necessary step in the second-generation bioethanol production technology. The lignocellulose complex is destroyed during this process, and this allows hydrolytic enzymes access to the surface of cellulose fibers. The pre-treatment is the most energy-consuming stage in bioethanol production technology, since it usually occurs at high temperature and pressure for a significant time. One of the ways to improve the efficiency of this process is the use of energy-efficient equipment that allows intensifying heat and mass transfer. An example of such equipment is a rotary-pulsation apparatus, which are effective devices in stirring, homogenization, dispersion technologies, etc. The treatment of wheat straw in a rotary-pulsation apparatus was carried out under atmospheric pressure without external heat supply at solid/water ratios of 1:10 and 1:5 in the presence of alkali. It was determined that the treatment of the water dispersion of straw at ratio of 1:10 due to the energy dissipation during 70 minutes leads to the release of 42 % of lignin and 25.76 % of easily hydrolyzed polysaccharides. Changing the solid / water ratio from 1:10 to 1:5 leads to an increase in the yield of lignin and easily hydrolyzed polysaccharides to 58 and 33.38 %, respectively.

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Bioethanol Production from UK Seaweeds: Investigating Variable Pre-treatment and Enzyme Hydrolysis Parameters

BioEnergy Research ◽

10.1007/s12155-019-10054-1 ◽

2019 ◽

Vol 13 (1) ◽

pp. 271-285 ◽

Cited By ~ 4

Author(s):

Emily T. Kostas ◽

Daniel A. White ◽

David J. Cook

Keyword(s):

Large Scale ◽

Method Development ◽

Reaction Times ◽

Enzyme Hydrolysis ◽

Bioethanol Production ◽

Laminaria Digitata ◽

Treatment Conditions ◽

Water Based ◽

Ethanol Yields ◽

Pre Treatment

Abstract This study describes the method development for bioethanol production from three species of seaweed. Laminaria digitata, Ulva lactuca and for the first time Dilsea carnosa were used as representatives of brown, green and red species of seaweed, respectively. Acid thermo-chemical and entirely aqueous (water) based pre-treatments were evaluated, using a range of sulphuric acid concentrations (0.125–2.5 M) and solids loading contents (5–25 % [w/v]; biomass: reactant) and different reaction times (5–30 min), with the aim of maximising the release of glucose following enzyme hydrolysis. A pre-treatment step for each of the three seaweeds was required and pre-treatment conditions were found to be specific to each seaweed species. Dilsea carnosa and U. lactuca were more suited with an aqueous (water-based) pre-treatment (yielding 125.0 and 360.0 mg of glucose/g of pre-treated seaweed, respectively), yet interestingly non pre-treated D. carnosa yielded 106.4 g g−1 glucose. Laminaria digitata required a dilute acid thermo-chemical pre-treatment in order to liberate maximal glucose yields (218.9 mg glucose/g pre-treated seaweed). Fermentations with S. cerevisiae NCYC2592 of the generated hydrolysates gave ethanol yields of 5.4 g L−1, 7.8 g L−1 and 3.2 g L−1 from D. carnosa, U. lactuca and L. digitata, respectively. This study highlighted that entirely aqueous based pre-treatments are effective for seaweed biomass, yet bioethanol production alone may not make such bio-processes economically viable at large scale.

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Bioethanol Production from Indigenous Algae

International Journal of Environment ◽

10.3126/ije.v4i1.12182 ◽

2015 ◽

Vol 4 (1) ◽

pp. 112-120 ◽

Cited By ~ 2

Author(s):

Madhuka Roy ◽

Krishnendu Kundu ◽

V. R. Dahake

Keyword(s):

Fossil Fuel ◽

Anaerobic Fermentation ◽

Biofuel Production ◽

Bioethanol Production ◽

Short Period ◽

Treatment Stage ◽

Fuel Characterization ◽

Complex Carbohydrates ◽

Pre Treatment

Enhanced rate of fossil fuel extraction is likely to deplete limited natural resources over short period of time. So search for alternative fuel is only the way to overcome this problem of upcoming energy crisis. In this aspect biofuel is a sustainable option. Agricultural lands cannot be compromised for biofuel production due to the requirement of food for the increasing population. Certain species of algae can produce ethanol during anaerobic fermentation and thus serve as a direct source for bioethanol production. The high content of complex carbohydrates entrapped in the cell wall of the microalgae makes it essential to incorporate a pre-treatment stage to release and convert these complex carbohydrates into simple sugars prior to the fermentation process. There have been researches on production of bioethanol from a particular species of algae, but this work was an attempt to produce bioethanol from easily available indigenous algae. Acid hydrolysis was carried out as pre-treatment. Gas Chromatographic analysis showed that 5 days’ fermentation by baker’s yeast had yielded 93% pure bioethanol. The fuel characterization of the bioethanol with respect to gasoline showed comparable and quite satisfactory results for its use as an alternative fuel.DOI: http://dx.doi.org/10.3126/ije.v4i1.12182International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15, page: 112-120

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