Selective Primary Oxidation of Lignin Streams from Butanol‐Pretreated Agricultural Waste Biomass

Agricultural waste biomass has already been transferred to bioethanol and used as energy related products, although many issues such as efficiency and productivity still to be overcome. In this study, the protein engineering was applied to generate enzymes with completely reversed coenzyme specificity and developed recombinant yeasts containing those engineered enzymes for construction of an efficient biomass-ethanol conversion system. Recombinant yeasts were constructed with the genes encoding a wild type xylose reductase (XR) and the protein engineered xylitol dehydrogenase (XDH) (with NADP) of Pichia stipitis. These recombinant yeasts were characterized based on the enzyme activity and fermentation ability of xylose to ethanol. The protein engineered enzymes were expressed significantly in Saccharomyces cerevisiae as judged by the enzyme activity in vitro. Ethanol fermentation was measured in batch culture under anaerobic conditions. The significant enhancement was found in Y-ARS strain, in which NADP+-dependent XDH was expressed; 85% decrease of unfavorable xylitol excretion with 26% increased ethanol production, when compared with the reference strain expressing the wild-type XDH. Keywords: Agricultural waste biomass; Protein engineering; Xylitol dehydrogenase; Xylose-fermentation; Eethanol production. © 2010 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v2i2.2882 J. Sci. Res. 2 (2), 351-361 (2010)

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Continuous Fixed-Bed Column Studies on Congo Red Dye Adsorption-Desorption Using Free and Immobilized Nelumbo nucifera Leaf Adsorbent

Polymers ◽

10.3390/polym14010054 ◽

2021 ◽

Vol 14 (1) ◽

pp. 54

Author(s):

Vairavel Parimelazhagan ◽

Gautham Jeppu ◽

Nakul Rampal

Keyword(s):

Congo Red ◽

Agricultural Waste ◽

Fixed Bed ◽

Dye Adsorption ◽

Nelumbo Nucifera ◽

Substantial Contribution ◽

Flow Mode ◽

Waste Biomass ◽

Column Studies ◽

Fixed Bed Column

The adsorption of Congo red (CR), an azo dye, from aqueous solution using free and immobilized agricultural waste biomass of Nelumbo nucifera (lotus) has been studied separately in a continuous fixed-bed column operation. The N. nucifera leaf powder adsorbent was immobilized in various polymeric matrices and the maximum decolorization efficiency (83.64%) of CR occurred using the polymeric matrix sodium silicate. The maximum efficacy (72.87%) of CR dye desorption was obtained using the solvent methanol. Reusability studies of free and immobilized adsorbents for the decolorization of CR dye were carried out separately in three runs in continuous mode. The % color removal and equilibrium dye uptake of the regenerated free and immobilized adsorbents decreased significantly after the first cycle. The decolorization efficiencies of CR dye adsorption were 53.66% and 43.33%; equilibrium dye uptakes were 1.179 mg g–1 and 0.783 mg g–1 in the third run of operation with free and immobilized adsorbent, respectively. The column experimental data fit very well to the Thomas and Yoon–Nelson models for the free and immobilized adsorbent with coefficients of correlation R2 ≥ 0.976 in various runs. The study concludes that free and immobilized N. nucifera can be efficiently used for the removal of CR from synthetic and industrial wastewater in a continuous flow mode. It makes a substantial contribution to the development of new biomass materials for monitoring and remediation of toxic dye-contaminated water resources.

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Microwave-Driven Biorefinery for Utilization of Food and Agricultural Waste Biomass

Waste Biorefinery ◽

10.1016/b978-0-444-63992-9.00013-6 ◽

2018 ◽

pp. 393-408 ◽

Cited By ~ 2

Author(s):

Shuntaro Tsubaki ◽

Jun-ichi Azuma ◽

Satoshi Fujii ◽

Rawel Singh ◽

Bhaskar Thallada ◽

...

Keyword(s):

Agricultural Waste ◽

Waste Biomass

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Corncob as a Substrate for the Cultivation of Lentinula Edodes

10.21203/rs.3.rs-241916/v1 ◽

2021 ◽

Author(s):

Hailong Yu ◽

Dan Zhang ◽

Lujun Zhang ◽

Qiaozhen Li ◽

Chunyan Song ◽

...

Keyword(s):

Lentinula Edodes ◽

Agronomic Traits ◽

Agricultural Waste ◽

Growth Yield ◽

Nutritional Composition ◽

Biological Efficiency ◽

Waste Biomass ◽

Chemical Profile ◽

Nutritional Profile ◽

Mycelia Growth

Abstract Corncob is a major agricultural waste in the world. The study aims to evaluate the effect of using corncob as a substrate for Lentinula edodes cultivation, so as to provide an economic and eco-friendly approach to transform waste biomass into high quality edible mushrooms (whose original substrate - wood - is becoming difficult to obtain these days). 6 formulas containing gradient proportions of corncob and a sawdust control were applied (100 cultivation bed-log per group), and substrate chemical profile were monitored. Effects of formula on mycelia growth, yield, biological efficiency, and agronomic traits and nutritional profile of mushrooms were investigated. The formula composing of 50% corncob, 28% sawdust, 20% wheat bran, and 2% gypsum showed the best performance with the fastest mycelia growth, better log browning, the highest yield (722.08 g/log) and summit biological efficiency (80.23%). The determined carbon/nitrogen in this substrate was 66.84. Yields in groups using 18 ~ 58% corncob were significantly improved comparing to the sawdust control, indicating a strong boosting effects of corncob. Agronomic traits of fruit bodies, such as pileus and stipe sizes, were not much affected by tested formulas. However, addition of corncob had an influence on nutritional composition of mushrooms, the polysaccharide content in mushrooms peaked (4.51g/100g) when the substrate contains 40% corncob. These results revealed an excellent potential of corncob when used as a main substrate ingredient for L. edodes cultivation.

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Synthesis and characterization of rice husk biochar via hydrothermal carbonization for wastewater treatment and biofuel production

Scientific Reports ◽

10.1038/s41598-020-75936-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Nazia Hossain ◽

Sabzoi Nizamuddin ◽

Gregory Griffin ◽

Periasamy Selvakannan ◽

Nabisab Mujawar Mubarak ◽

...

Keyword(s):

Rice Husk ◽

Agricultural Waste ◽

Value Added ◽

Hydrothermal Carbonization ◽

Catalytic Performance ◽

Biofuel Production ◽

Suspension Stability ◽

Waste Biomass ◽

Suitable Material ◽

Rice Husk Biochar

Abstract The recent implication of circular economy in Australia spurred the demand for waste material utilization for value-added product generations on a commercial scale. Therefore, this experimental study emphasized on agricultural waste biomass, rice husk (RH) as potential feedstock to produce valuable products. Rice husk biochar (RB) was obtained at temperature: 180 °C, pressure: 70 bar, reaction time: 20 min with water via hydrothermal carbonization (HTC), and the obtained biochar yield was 57.9%. Enhancement of zeta potential value from − 30.1 to − 10.6 mV in RB presented the higher suspension stability, and improvement of surface area and porosity in RB demonstrated the wastewater adsorption capacity. Along with that, an increase of crystallinity in RB, 60.5%, also indicates the enhancement of the catalytic performance of the material significantly more favorable to improve the adsorption efficiency of transitional compounds. In contrast, an increase of the atomic O/C ratio in RB, 0.51 delineated high breakdown of the cellulosic component, which is favorable for biofuel purpose. 13.98% SiO2 reduction in RB confirmed ash content minimization and better quality of fuel properties. Therefore, the rice husk biochar through HTC can be considered a suitable material for further application to treat wastewater and generate bioenergy.

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