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Advancement of fermentable sugars from fresh elephant ear plant weed for efficient bioethanol production

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Marlen Trejo at The University of Sydney
Marlen Trejo
Prakash Bhuyar at Maejo University
Prakash Bhuyar
Yuwalee Unpaprom at Maejo University
Yuwalee Unpaprom
Natthawud Dussadee at Maejo University
Natthawud Dussadee
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Abstract and Figures

Bioethanol is considered one of the most promising next-generation automotive fuels, as it is carbon neutral and can be produced from renewable resources, like lignocellulosic materials. The present research investigation aimed to utilize the elephant ear plant, a hazardous plant (weed) also considered an invasive species, as a font of non-edible lignocellulosic biomass for bioethanol production. The freshly collected elephant ear plant (leaves and stalk) was chopped into small pieces (1–2 cm) and then homogenized to a paste using a mechanical grinder. The sample pretreatment was done by flying ash for three different time durations (T1 = 0 min, T2 = 15 min, and T3 = 30 min) with 3 replications. All treatment samples were measured for total sugar and reducing sugar content. The concentration of reducing sugar archived was T1 = 0.771 ± 0.1 mg/mL, T2 = 0.907 ± 0.032 mg/mL, and T3 = 0.895 ± 0.039 mg/mL, respectively. The results revealed that the chemical composition was different among treatments. The hydrolysis was performed using cellulase enzymes at 35 °C for the hydrolysis process. The hydrolysate was inoculated with 1% of S. cerevisiae and maintained at room temperature without oxygen for 120 h. Bioethanol concentration was measured by using an ebulliometer. The efficient ethanol percentage was 1.052 ± 0.03 mg/mL achieved after the fermentation. Therefore, the elephant ear plant invasive weed could be an efficient feedstock plant for future bioethanol production.
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Vol.:(0123456789)
Environment, Development and Sustainability (2022) 24:7377–7387
https://doi.org/10.1007/s10668-021-01753-x
1 3
Advancement offermentable sugars fromfresh elephant ear
plant weed forefficient bioethanol production
MarlenTrejo1,2· PrakashBhuyar1,2· YuwaleeUnpaprom2,3· NatthawudDussadee1·
RameshprabuRamaraj1,2
Received: 8 July 2021 / Accepted: 9 August 2021 / Published online: 17 August 2021
© The Author(s), under exclusive licence to Springer Nature B.V. 2021
Abstract
Bioethanol is considered one of the most promising next-generation automotive fuels, as
it is carbon neutral and can be produced from renewable resources, like lignocellulosic
materials. The present research investigation aimed to utilize the elephant ear plant, a haz-
ardous plant (weed) also considered an invasive species, as a font of non-edible lignocel-
lulosic biomass for bioethanol production. The freshly collected elephant ear plant (leaves
and stalk) was chopped into small pieces (1–2cm) and then homogenized to a paste using
a mechanical grinder. The sample pretreatment was done by flying ash for three different
time durations (T1 = 0 min, T2 = 15 min, and T3 = 30 min) with 3 replications. All treat-
ment samples were measured for total sugar and reducing sugar content. The concentra-
tion of reducing sugar archived was T1 = 0.771 ± 0.1 mg/mL, T2 = 0.907 ± 0.032 mg/mL,
and T3 = 0.895 ± 0.039 mg/mL, respectively. The results revealed that the chemical com-
position was different among treatments. The hydrolysis was performed using cellulase
enzymes at 35°C for the hydrolysis process. The hydrolysate was inoculated with 1% of
S. cerevisiae and maintained at room temperature without oxygen for 120h. Bioethanol
concentration was measured by using an ebulliometer. The efficient ethanol percentage
was 1.052 ± 0.03mg/mL achieved after the fermentation. Therefore, the elephant ear plant
invasive weed could be an efficient feedstock plant for future bioethanol production.
Keywords Elephant ear plant· Total sugar· Reducing sugar· Hydrolysis· Fermentation
1 Introduction
Globally, derived fossil fuels are the primary energy source, especially in the transportation
sector (Bhuyar etal., 2021; Ramaraj etal., 2021a, b). Consequently, the greenhouse gases
released into the atmosphere have increased 1.4 per cent per year on average, according
* Rameshprabu Ramaraj
rameshprabu@mju.ac.th; rrameshprabu@gmail.com
1 School ofRenewable Energy, Maejo University, ChiangMai50290, Thailand
2 Sustainable Resources andSustainable Engineering Research Lab, Maejo University,
ChiangMai50290, Thailand
3 Program inBiotechnology, Faculty ofScience, Maejo University, ChiangMai50290, Thailand
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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Article
  • Apr 2021
Utilized and waste jasmine flower contains a high portion of organic carbohydrate and other organic acids, making it a suitable substrate for bioethanol production. This study was designed to estimate the prospective of waste jasmine flower biomass applied with chemical (alkaline) and thermal pretreatment applied on samples through bioethanol production effi-ciencies. Therefore, pretreatment and enzymatic hydrolysis are directed to disrupt the complex cell wall layer and improve the accessibility towards polysaccharide fraction. Also, applying response surface methodology tools during fermentative bioethanol production to study the interactive effects of different bioprocess variables for higher bioethanol yield in batch small and large scale model is discussed. The immobilized yeast between jasmine found that jasmine sugar utilization was 50%. The jasmine flower's ethanol production was 6.54 g/L and after distillation of jasmine was 31.40 g/L at pH 4.5. Results showed that this immobilized yeast method could be successfully used for bioethanol production from waste jasmine flower.
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Utilization of Aqueous Weeds for Biofuel Production: Current Status and Future Prospects
Chapter
  • Feb 2021
The energy crisis is one of the biggest issues encountered by today’s world. Rapid economic growth and population explosion have resulted in a substantial increase in energy (fuel) consumption, especially in the transportation sector. The currently available sources of energy (such as fossil fuels) are limited and are consumed at an alarming rate throughout the world. Such limited sources of energy are likely to get exhausted over time
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Comparative analysis of fresh and dry free-floating aquatic plant Pistia stratiotes via chemical pretreatment for second-generation (2G) bioethanol production
Article
  • Feb 2021
In the effort to manage global warming and fossil carbon emissions, many countries are suggesting brand-new policies to make their energy matrix much more renewable. The boost share of bioethanol as a transportation fuel becomes a short-term option since its production technology is fully grown and combined with gasoline. The 2nd generation ethanol still has involvement on the planet biofuels circumstance. In this study, water lettuce (Pistia stratiotes) fresh and dry biomass applied with alkalis (NaOH) and acid (H2SO4) were combined to pretreat the abundant free-floating aquatic plant water lettuce biomass. Naturally, the water lettuce accumulates food in the form of starch, suitable for bioethanol production. The results showed that the highest total sugar (11.350 ± 0.09 %), reducing sugar (4.773 ± 0.15 %), and ethanol (15. 385 g/L) were obtained after pretreatment of dried water lettuce with cellulase. Consequently, water lettuce was high feasible for sustainable bioethanol production.
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Bioethanol production from the comparison between optimization of sorghum stalk and sugarcane leaf for sugar production by chemical pretreatment and enzymatic degradation
Article
  • Oct 2020
  • FUEL
This work reports the comparison of optimized pretreatment models on total sugar (TS) production from sugarcane leaf (SL) with sorghum stalk (SS) utilization to decompose the lignocellulosic biomass into oligosaccharide (OS). The accumulation variables were examined in the pretreatment model, including pretreatment time (1–3 days), concentrations of sodium hydroxide (NaOH) from 1 to 2% (w/v), and heating temperatures from 30 to 40 °C. TS productions were optimized by using response surface methodology (RSM) on central composite design (CCD) models. These models indicated excellent determination coefficients (R²) ranged from 0.9820 to 0.9900 and are significant. Process optimization showed that the highest TS yield was achieved of 32.612 g/L and 38.977 g/L for NaOH pretreatment at condition (2)% (w/v) NaOH at the temperature of 40 °C for 3 days. After pretreatment, the biomass was degraded using a cellulase enzyme to form the fermentable sugar for ethanol production by Saccharomyces cerevisiae TISTR5020. The maximum bioethanol yield of 8.374 ± 1.813 g/L was achieved at 2 days of fermentation time when compared with bioethanol yield (5.234 ± 0.907 g/L) of 4 days fermentation time.
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