scholarly journals The Effect of Degradation of Soda Lignin Using Pd/SO42−/ZrO2 as a Catalyst: Improved Reactivity and Antioxidant Activity

Polymers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1218 ◽  
Author(s):  
Shengming Zhang ◽  
Guizhen Fang ◽  
Haitao Chen ◽  
Qian Lang

To the value-added application of the soda lignin by improving its reactivity and antioxidant activity, a self-made Pd/SO42−/ZrO2 catalyst was used to catalyze the degradation reaction of soda lignin. The catalyst was loaded with the palladium of 1.47 wt.% while retaining the super acidity of SO42−/ZrO2. The reaction condition was determined as follows: the dioxane-water solution was selected as the reaction solution, the addition amount of the catalyst was 5 wt.% of the soda lignin, the system was heated at 100 °C for 4 h under a hydrogen pressure of 3 MPa. The reactivity of the catalyzed-soda lignin compared to the soda lignin before the reaction was significantly improved: the values of phenolic hydroxyl groups and total hydroxyl groups were increased by 35.3% and 97.1%, respectively, and the value of methoxy groups was decreased by 13%. Approximately 63.3% of the β-O-4 bonds were cleaved, which resulted in a reduction of the weight average molecular weight from 8200 g·mol−1 to 4900 g·mol−1. At the same time, the EC50 values of the catalyzed-soda lignin on DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS+ (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radicals scavenging were decreased by 20.6% and 32.6%, respectively, and the reducing power of catalyzed-soda lignin at the absorption value of 0.5 was increased by 10.5%. The Pd/SO42−/ZrO2 catalyst works by breaking the β-O-4 linkages and degrading the methoxy groups. The catalyzed-soda lignin exhibits the possibility of being used as the antioxidants, grafting precursors, adhesive additives, and raw materials for lignin/polymer composites.

2020 ◽  
Vol 189 ◽  
pp. 02025
Author(s):  
Zhou Yong Dong ◽  
Xin Song Yin ◽  
Shu Lin Liu ◽  
Tie Hua Zhang ◽  
Hui Ren ◽  
...  

This paper studies the optimization of ultrasonic-assisted extraction of polysaccharides from Oenothera biennis L. leaves using Box-Behnken design, and their in vitro antioxidant activity and structure. It is demonstrated that the optimum extraction conditions are: the ultrasonic power at 400 W, solvent-tosample ratio of 23:1 (mL/g), ultrasonication temperature at 53 °C, and time for 36 min, under which the yield of polysaccharides from Oenothera biennis L. leaves, namely 3.54%, remains close to the predicted value in the model. The assays of the scavenging effect on DPPH and hydroxyl free radicals, and of the reducing power indicate that polysaccharides from Oenothera biennis L. leaves possess strong antioxidant activity and certain relationship exists between their dose and effect in the concentration range of the experiment; Fourier IR spectroscopy reveals that characteristic absorption peak of polysaccharides can be seen from the sample; the DE-52 cellulose column chromatography, HPLC profiles, and GC-MS chromatogram identify the obtained OCP-2 as heteropolysaccharides, whose major components, including arabinose, mannose, galactose, and talose, have an average molecular weight of 5435 Da.


2020 ◽  
pp. 13-22
Author(s):  
Tahani Al-idee ◽  
Hoda Habbal ◽  
Francois Karabt ◽  
Hussien Alzubi

The aim of this research is to study some functional properties and the antioxidant activity of cherry gum, collected from Serghaya and Suwayda in Syria, and to compare these features with those of Arabic gum. The values of the hydroxyl groups for the Arabic gum, Serghaya and Suwayda cherry gums were 757.1, 655.1 and 564.3 mg KOH/gm, respectively. The solubility of exudate gums ranged from 53.53 to 86.53% and was arranged as follows: Arabic gum>Serghaya cherry gum >Suwayda cherry gum. Gum solubility increased with rising the temperature. Water and oil holding capacities of cherry gums were significantly higher (p<0.05) than those of Arabic gum, while their emulsifying capacity was significantly lower than that of Arabic gum. The antioxidant activity of the gum was evaluated using the DPPH scavenging activity method and reducing power method. The inhibition percentages of DPPH were 51.52%, 23.23% and 21.19% for Serghaya, Suwayda and Arabic gums, respectively. The antioxidant activities of Serghaya and Suwayda gums using the reducing power method were 753.12 and 312.93 meq ascorbic acid/100gm, whereas Arabic gum didnot exhibit any Fe+3 reducing activity. All of gum types showed similar FT-IR spectra.


2012 ◽  
Vol 550-553 ◽  
pp. 1352-1356
Author(s):  
Chun Ling Xiao ◽  
Hong Ying Li ◽  
Zhen Zhang ◽  
Rui Feng Liang

Using cherry tomatoes as raw materials, the experiment studies its antioxidant activity in different fermentation conditions . By measuring the content of flavonoid,and polyphenols, clearance to DPPH •and OH• , and reducing power of cherry tomatoes wine in different fermentation conditions, theantioxidation capability can be judged. The results show that content of alcohol achieves 16 °, concentration of SO2 is110 mg/L, fermentation time is between3 d and 4 d, the antioxidant ability of cherry tomato fruit wine is optimum.


2013 ◽  
Vol 634-638 ◽  
pp. 1066-1070 ◽  
Author(s):  
Yan Fang Zhang ◽  
Chun Ling Xiao ◽  
Xin Jia ◽  
Qiong Jie Li ◽  
Yuan Yuan Xue ◽  
...  

With black beans as raw materials, different factors on natural black beans peptide yield influence, and through the establishment of DPPH • system, OH • system, reducing power system measurement for the determination of different concentration of black soya bean peptide oxidation stability. The results showed that the liquid material ratio 17.5,leaching 42°C,extracting 55 min, black beans peptide extraction is 2.386 mg/g. Black beans peptide in various system all have certain oxidative stability, in the concentration of 0.04mg/ml to 74.05% clearance of DPPH• , in 0.06mg/ml concentration of OH•clearance rate is 80.48%, 0.08 mg/ml concentrations reduction force is 0.745, and in these three system natural black beans peptide oxidation stability are better than those of contrast VC is strong .


2020 ◽  
pp. 13-22
Author(s):  
Tahani Al-idee ◽  
Hoda Habbal ◽  
Francois Karabt ◽  
Hussien Alzubi

The aim of this research is to study some functional properties and the antioxidant activity of cherry gum, collected from Serghaya and Suwayda in Syria, and to compare these features with those of Arabic gum. The values of the hydroxyl groups for the Arabic gum, Serghaya and Suwayda cherry gums were 757.1, 655.1 and 564.3 mg KOH/gm, respectively. The solubility of exudate gums ranged from 53.53 to 86.53% and was arranged as follows: Arabic gum>Serghaya cherry gum >Suwayda cherry gum. Gum solubility increased with rising the temperature. Water and oil holding capacities of cherry gums were significantly higher (p<0.05) than those of Arabic gum, while their emulsifying capacity was significantly lower than that of Arabic gum. The antioxidant activity of the gum was evaluated using the DPPH scavenging activity method and reducing power method. The inhibition percentages of DPPH were 51.52%, 23.23% and 21.19% for Serghaya, Suwayda and Arabic gums, respectively. The antioxidant activities of Serghaya and Suwayda gums using the reducing power method were 753.12 and 312.93 meq ascorbic acid/100gm, whereas Arabic gum didnot exhibit any Fe+3 reducing activity. All of gum types showed similar FT-IR spectra.


2014 ◽  
Vol 881-883 ◽  
pp. 378-383
Author(s):  
Qiong Jie Li ◽  
Chun Ling Xiao

With black soybean as raw materials, 50% ethanol as the extractant, at 70°C, pH1.0, solid-liquid ratio of 1:100(g:mL), at 90min were used to extract the pigment of black soybean Through the establishment of DPPH•,•OH, superoxide anion free radicals, reducing power and hydrogen peroxide. The results show: its ability of scavenging DPPH•, •OH, hydrogen peroxide is far better than ascorbic acid. The pigment at concentration of 0.6mg/mL shows a scavenging rate for DPPH• up to 88.29%,and for •OH 89.36%,for hydrogen peroxide89.75%.In addition,the general reducing power and scavenging rate for superoxide anion solution of the pigment are a little worse than those of ascorbic acid.


2014 ◽  
Vol 675-677 ◽  
pp. 1629-1633 ◽  
Author(s):  
Chun Ling Xiao ◽  
Ying Ren ◽  
Hui Ling Ding

In this experiment black soybeans as raw materials,different factor on black beans polyphenol extraction yield influence,and studied the polyphenols antioxidant activity through establishing DPPH· system,·OH system and reducing power system,and compared with Vc. The result showed that:the optimum extraction conditions were the ratio of liquid to Solid was 32:1,ethanol concentration 48%,time 95min,temperature 90 °C.In these conditions, the yield of polyphenols was 8.953mg/g. The scavenging effects of polyphenols and Vc on DPPH·, ·OH force increased with increasing concentration,and the scavenging effects of polyphenols on DPPH· and ·OH higher than Vc when between in 11~31 μg/mL.When concentration is more than 12μg/mL,the scavenging effects of polyphenols on ·OH is higher than Vc.


2009 ◽  
Vol 37 (05) ◽  
pp. 977-989 ◽  
Author(s):  
Ying Wang ◽  
Min Wang ◽  
Yun Ling ◽  
Weiqiang Fan ◽  
Yufeng Wang ◽  
...  

A water-soluble polysaccharide named CPS1 had been isolated from C. sinensis mycelium by hot water extraction, ethanol precipitation, anion-exchange, and gel-permeation chromatography. UV spectra, FTIR spectra, partial acid hydrolysis, PMP precolumn derivation, periodate oxidation and Smith degradation studies were conducted to elucidate its structure. The results indicated that CPS1 was a glucomannogalactan with the monosaccharide composition of glucose: mannose: galactose = 2.8: 2.9: 1. The total carbohydrate content of CPS1 was 99.0%. The weight-average molecular weight was 8.1 × 103 Da . The results predicted (1 → 2) and (1 → 4)-linkage of mannose, (1 → 3)-linkage of galactose, (1 → ) and (1 → 3, 6)-linkage of glucose composed the backbone of CPS1. CPS1 was also evaluated for its antioxidant activity in vitro, including scavenging effects on the hydroxyl radicals, the reducing power, Fe2+ -chelating activity, scavenging effect on superoxide radicals, as well as the inhibition of hydrogen peroxide induced haemolysis. CPS1 showed a high antioxidant effect, especially scavenging effect of hydroxyl radicals, the reducing power and Fe2+ -chelating activity. The results provide scientific support for the antioxidant activity and indicated a connection between antioxidant activity and reparation of renal failure.


2020 ◽  
pp. 48-55
Author(s):  
M.E. Sharanda ◽  
◽  
E.A. Bondarenko ◽  

Ethylene glycol and propylene glycol are important representatives of polyols. On an industrial scale, they are obtained from petrochemical raw materials. Within a decade, significant efforts were made for the producing of polyols from biologically renewable raw materials - carbohydrates. The general trend for carbohydrate hydrogenolysis includes application of liquid-phase process with the use of modified metal-oxide catalysts, at 120-120 ° C and pressure of 3MPa or above. So high pressure is used for the reason to increase hydrogen solubility, and also due to the high partial pressure of low boiling solvents. We supposed that usage of high boiling solvents could allow hydrogenolysis to be performed at the lower pressure. Ethylene glycol and propylene glycol are of particular interest as such kind of solvent since they are both the main products of glucose hydrogenolysis. In this work, the process of hydrogenolysis of glucose and fructose over Cu / MgO-ZrO2 catalyst have been studied at temperature range of 160-200 °C and a pressure of 0.1-0.3 MPa in a flow reactor. The solvents were simultaneously the target products of the reaction - ethylene glycol and / or propylene glycol. Gas chromatography and 13C NMR were used for the reaction products identification. It was found that the solubility of glucose in propylene glycol is 21 % by weight, and in ethylene glycol 62% by weight. It was pointed out that the process of hydrogenolysis can take place at a pressure close to atmospheric. Under these conditions, the conversion of hexoses reaches 96-100 %. The reaction products are preferably propylene glycol and ethylene glycol. The total selectivity for C3-2 polyols is 90-94 %, that is higher than in the hydrogenolysis of glucose in aqueous solution.


2013 ◽  
Vol 13 (1) ◽  
Author(s):  
Subiyanto Subiyanto

Palm oil industry in Indonesia has been growing rapidly. But, unfortunately the growth is only effective on upstream industry with low value products, such that potential downstream value added are not explored proportionally. The government is therefore in the process of developing an appropriate policy to strengthen the national palm oil downstream industry. This paper proposes that an approriate policy for developing palm oil downstream industry could be derived from the maps of value chain and existing technology capability of the industry. The result recommends that government policy should emphasize on the supply of raw materials, infrastructure and utilities, as well as developing the missing value chain industry, especially ethoxylation and sulfonation.


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