scholarly journals Delignification of Cistus ladanifer Biomass by Organosolv and Alkali Processes

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1127
Author(s):  
Júnia Alves-Ferreira ◽  
Ana Lourenço ◽  
Francisca Morgado ◽  
Luís C. Duarte ◽  
Luísa B. Roseiro ◽  
...  
Keyword(s):  
Steam Distillation ◽  
Enzymatic Saccharification ◽  
Added Value ◽  
Cistus Ladanifer ◽  
Reaction Conditions ◽  
Zone Electrophoresis ◽  
Monomeric Composition ◽  
Capillary Zone ◽  
Soluble Lignin ◽  
Pretreated Biomass

Residues of Cistus ladanifer obtained after commercial steam distillation for essential oil production were evaluated to produce cellulose enriched solids and added-value lignin-derived compounds. The delignification of extracted (CLRext) and extracted and hydrothermally pretreated biomass (CLRtreat) was studied using two organosolv processes, ethanol/water mixtures (EO), and alkali-catalyzed glycerol (AGO), and by an alkali (sodium hydroxide) process (ASP) under different reaction conditions. The phenolic composition of soluble lignin was determined by capillary zone electrophoresis and by Py-GC/MS, which was also used to establish the monomeric composition of both the delignified solids and isolated lignin. The enzymatic saccharification of the delignified solids was also evaluated. The ASP (4% NaOH, 2 h) lead to both the highest delignification and enzymatic saccharification (87% and 79%, respectively). A delignification of 76% and enzymatic hydrolysis yields of 72% were obtained for AGO (4% NaOH) while EO processes led to lower delignification (maximum lignin removal 29%). The residual lignin in the delignified solids were enriched in G- and H-units, with S-units being preferentially removed. The main phenolics present in the ASP and AGO liquors were vanillic acid and epicatechin, while gallic acid was the main phenolic in the EO liquors. The results showed that C. ladanifer residues can be a biomass source for the production of lignin-derivatives and glucan-rich solids to be further used in bioconversion processes.

scholarly journals Comparison of Efficiency and Cost of Methods for Conditioning of Slurries of Steam-Pretreated Softwood

2021 ◽  
Vol 9 ◽  
Author(s):  
Dimitrios Ilanidis ◽  
Stefan Stagge ◽  
Björn Alriksson ◽  
Adnan Cavka ◽  
Leif J. Jönsson
Keyword(s):  
Sodium Borohydride ◽  
Sodium Sulfite ◽  
Solid Phase ◽  
Enzymatic Saccharification ◽  
Sodium Dithionite ◽  
Microbial Fermentation ◽  
Reaction Conditions ◽  
Standard Methods ◽  
Cost Efficient ◽  
Pretreated Biomass

Inhibitors formed during pretreatment impair lignocellulose bioconversion by making enzymatic saccharification and microbial fermentation less efficient, but conditioning of slurries and hydrolysates can improve fermentability and sometimes also enzymatic digestibility. Conditioning of pretreated softwood using four industrial reducing agents (sodium sulfite, sodium dithionite, sodium borohydride, and hydrogen) was compared with standard methods, such as overliming and treatment with activated charcoal. A dosage of approx. 1 mM sulfur oxyanion (sulfite or dithionite) per percent water-insoluble solids (WIS) in the slurry was found to result in good fermentability. Treatment of 10–20% WIS slurries with 15 mM sulfur oxyanion under mild reaction conditions (23°C, pH 5.5) resulted in sulfonation of the solid phase and saccharification improvements of 18–24% for dithionite and 13–16% for sulfite. Among the different conditioning methods studied, treatment of slurries with sodium sulfite was superior with respect to cost-efficient improvement of fermentability. Treatments of slurry or pretreatment liquid with 15 mM sulfite or dithionite resulted in 58–76% reduction of the content of formaldehyde. The comparison indicates that conditioning of pretreated biomass using sulfur oxyanions warrants further attention.

Zoledronate and Related Impurities Analysis by Capillary Zone Electrophoresis

2014 ◽  
Vol 10 (2) ◽  
pp. 231-234 ◽  
Author(s):  
Gisela Alvarez ◽  
María Foglia ◽  
Daniela Camporotondi ◽  
S. Giorgieri ◽  
Martín Desimone ◽  
...  
Keyword(s):  
Capillary Zone Electrophoresis ◽  
Related Impurities ◽  
Zone Electrophoresis ◽  
Capillary Zone

Synthesis of Fragments of the Vasoactive Intestinal Peptide (VIP) and Analysis of Their Residual Biological Activities

1995 ◽  
Vol 60 (7) ◽  
pp. 1229-1235 ◽  
Author(s):  
Ivana Zoulíková ◽  
Ivan Svoboda ◽  
Jiří Velek ◽  
Václav Kašička ◽  
Jiřina Slaninová ◽  
...  
Keyword(s):  
Amino Acid ◽  
Biological Activities ◽  
Residual Activity ◽  
Detailed Examination ◽  
Amino Acid Residues ◽  
Linear Peptide ◽  
Zone Electrophoresis ◽  
Capillary Zone

The vasoactive intestinal (poly)peptide (VIP) is a linear peptide containing 28 amino acid residues, whose primary structure indicates a low metabolic stability. The following VIP fragments, as potential metabolites, and their analogues were prepared by synthesis on a solid: [His(Dnp)1]VIP(1-10), VIP(11-14), [D-Arg12]VIP(11-14), [Lys(Pac)15,21,Arg20]VIP(15-22), and VIP(23-28). After purification, the peptides were characterized by amino acid analysis, mass spectrometry, RP HPLC, and capillary zone electrophoresis. In some tests, detailed examination of the biological activity of the substances in vivo and in vitro gave evidence of a low, residual activity of some fragments, viz. a depressoric activity in vivo for [His(Dnp)1]VIP(1-10) and a stimulating activity for the release of α-amylase in vitro and in vivo for [Lys(Pac)15,21,Arg20]VIP(15-22) and VIP(23-28).

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