Sustainable production of benzene from lignin.
Ontology highlight
ABSTRACT:
SUBMITTER: Meng Q
PROVIDER: S-EPMC8313573 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:In this work, a sustainable chemical process was developed through the Fischer esterification of Protobind® lignin, a wheat straw soda lignin, and phloretic acid, a naturally occurring phenolic acid. It aimed at increasing the reactivity of lignin by enhancing the number of unsubstituted phenolic groups via a green and solvent-free chemical pathway. The structural features of the technical and esterified lignins were characterized by complementary spectroscopic techniques, including 1H, 13C, 31P, and two-dimensional analysis. A substantial increase in p-hydroxyphenyl units was measured (+64%, corresponding to an increase of +1.3 mmol g-1). A full factorial design of the experiment was employed to quantify the impact of critical variables on the conversion yield. The subsequent statistical analysis suggested that the initial molar ratio between the two precursors was the factor predominating the yield of the reaction. Hansen solubility parameters of both the technical and esterified lignins were determined by solubility assays in multiple solvents, evidencing their high solubility in common organic solvents. The esterified lignin demonstrated a better thermal stability as the onset of thermal degradation shifted from 157 to 220 °C, concomitantly to the shift of the glass transition from 92 to 112 °C. In conclusion, the esterified lignin showed potential for being used as sustainable building blocks for composite and thermoset applications.
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Project description:This study aims to reveal genes related to lignin production in Cenchrus purpureus through RNA-Seq. This species is widely used as forrage for cattle, and for the last years, due to its high biomass yield, has been considered as source to lignocellulosic ethanol. Given those two importances, lignin is a molecule related to low digestibility in cattle and recalcitrance in biofuel production. Eight samples were chosen from previous lignin production and forage quality data; four samples had low lignin production, and four had high lignin production. The highest nodes were collected for RNA extraction using TRIzol reagent, following Jordon-Thaden et a;. (2015) protocol. The cDNA library preparation was generated according to Illumina TruSeq Stranded mRNA Sample Prep kit protocol, and RNA sequencing was performed using HiSeq 2500 sequencer. Quality control was measured by FastQC software v 0.11.8. The sequenced reads were aligned to Cenchrus purpureus genome through STAR software v. 2.5.2b (Dobin et al., 2012). After that, the transcriptome was assembled using Stringtie v 2.0.4 software (Pertea et al., 2015). Salmon v 0.7.2 software (Patro et al., 2017) was used to quantify the sequenced reads. The DEG was identified using DESeq2 package, and genes functions were annotated through Trinotate software (Bryant et al., 2017). In total, approximately 130 million reads were sequenced. The final assembled transcriptome was formed by 101,169 transcripts. The differential expressed genes analysis revealed 52 significatively genes. Here, we highlighted genes related to sterol, L-serine and terpene biosynthetic process.
2021-10-01 | GSE174718 | GEO
Project description:This study aims to reveal genes related to lignin production in Urochloa humidicola through RNA-Seq. This species is widely used as forrage for cattle, being some species of Urochloa responsible for 85% of pastures in Brazil. Given this importance, lignin is a molecule directly related to low digestibility in cattle. Eight samples were chosen from previous lignin production and forage quality data; four samples had low lignin production, and four had high lignin production. The second extended leaves were collected for RNA extraction using RNeasy® Plant Mini Kit. The cDNA library preparation was generated according to Illumina TruSeq Stranded mRNA Sample Prep kit protocol, and RNA sequencing was performed using HiSeq 2500 sequencer. Quality control was measured by FastQC software v 0.11.8. As Urochloa humidicola does not have a sequenced genome, a transcriptome assembly was built by two approaches: through Trinity v 2.8.4 (Grabherr et al., 2011), and Stringtie v 2.0.4 software (Pertea et al., 2015), using Urochloa ruziziensis as reference genome. Then, the final transcriptome was assembled using those two de novo assembles by PASA v 2.2 (Haas et al., 2003). Salmon v 0.7.2 software (Patro et al., 2017) was used to quantify the sequenced reads. The DEG was identified using DESeq2 package, and genes functions were annotated through Trinotate software (Bryant et al., 2017). In total, approximately 123 million reads were sequenced. The final assembled transcriptome was formed by 48,695 transcripts. The differential expressed genes analysis revealed 258 significatively genes. Here, we highlighted genes related to flavonoid biosynthetic process, regulation of phenylpropanoid metabolic process, and Myb-like DNA-binding domain.
2021-09-30 | GSE175577 | GEO
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