STUDIES ON LIGNIN AND RELATED COMPOUNDS: XIII. THE STRUCTURE AND PROPERTIES OF GLYCOL LIGNIN

1935 ◽  
Vol 13b (1) ◽  
pp. 35-47 ◽  
Author(s):  
K. R. Gray ◽  
E. G. King ◽  
Fritz Brauns ◽  
Harold Hibbert
Keyword(s):  
Chemical Composition ◽  
Ethylene Glycol ◽  
Soluble Fraction ◽  
Primary Alcohol ◽  
Hydriodic Acid ◽  
Structure And Properties ◽  
Spruce Wood ◽  
Derivatives Of ◽  
Related Compounds ◽  
Soluble Lignin

Lignin was extracted from spruce wood meal with ethylene glycol containing (a) 0.05% and (b) 0.2% hydrogen chloride. On purification the two glycol lignins were found to contain 16.9% OCH3 and 62.8% C., and 16.5% OCH3 and 64.7% C. respectively. The aqueous glycol mother liquor was found to contain a soluble lignin-carbohydrate compound. The glycol lignin could be separated into a chloroform-insoluble and a chloroform-soluble fraction, each having the same chemical composition and yielding the same methylated products. From the glycol lignin, purified by means of dioxane-ether, acetylated and methylated derivatives were prepared, as were also trityl derivatives of glycol lignin and premethylated glycol lignin.The introduction of three trityl groups indicates the presence of three primary alcohol groups in the original lignin. Glycol lignin can be both partially and completely demethylated by use of hydriodic acid. The effect of the glycol radical on the methoxyl value in the Zeisel determination was studied and an equation derived for the correction of the methoxyl value. The bearing of the results on the formula proposed previously (1) for methanol lignin is discussed.

scholarly journals New ent–Kaurane type Diterpene Glycoside, Pulicaroside-B, from Pulicaria Undulata L

2008 ◽  
Vol 3 (2) ◽  
pp. 1934578X0800300 ◽  
Author(s):  
Nasir Rasool ◽  
Viqar Uddin Ahmad ◽  
Naseem Shahzada ◽  
Muhammad A. Rashida ◽  
Aman Ullah ◽  
...  
Keyword(s):  
Spectral Data ◽  
Plant Extract ◽  
Soluble Fraction ◽  
2D Nmr ◽  
Spectroscopic Techniques ◽  
Spectral Evidence ◽  
Whole Plant ◽  
Derivatives Of ◽  
Related Compounds

Investigation of the n-butanol-soluble fraction of the whole plant extract of Pulicaria undulata yielded a new ent–kaurane type diterpene glycoside, pulicaroside-B (1), together with three known compounds, paniculoside-IV (2), roseoside (3), and corchoionol C (4). Compounds 3 and 4 are derivatives of α-ionol. The structures of the new and known compounds were elucidated by 1D- and 2D-NMR spectroscopic techniques, along with other spectral evidence, and by comparison of the spectral data with those of closely related compounds.

STUDIES ON LIGNIN AND RELATED COMPOUNDS: II GLYCOL-LIGNIN AND GLYCOL-ETHER-LIGNIN

1930 ◽  
Vol 2 (6) ◽  
pp. 364-375 ◽  
Author(s):  
Harold Hibbert ◽  
Léo Marion
Keyword(s):  
Ethylene Glycol ◽  
Monomethyl Ether ◽  
Glycol Ether ◽  
Free Alcohol ◽  
Wood Meal ◽  
Spruce Wood ◽  
Related Compounds

The extraction of spruce wood meal with ethylene glycol in the presence of 0.05% HCl leads to the isolation of a lignin derivative to which the name glycol-lignin is given. If the monomethyl ether of glycol be substituted for the free alcohol, a glycol-ether-lignin is obtained which has a much higher methoxyl content than glycol-lignin. The product of extraction is therefore a compound of lignin and the solvent. A comparison of the methoxyl content of the derivatives obtained from the two lignins by methylation and hydrolysis supports this conclusion. On oxidation, glycol-lignin gives rise to a product which forms a p-bromphenylhydrazone, identical with that obtained from the product of the oxidation of ethylene glycol under the same conditions. On hydrolysis with acids glycol-lignin yields, besides 0.7% formaldehyde, a substance which reduces Fehling's solution.

Lignin and related compounds. V. The hydrogenolysis of aspen wood lignin using rhodium-on-charcoal as catalyst

1978 ◽  
Vol 56 (7) ◽  
pp. 896-898 ◽  
Author(s):  
James M. Pepper ◽  
Reginald W. Fleming
Keyword(s):  
Lignin Degradation ◽  
Soluble Fraction ◽  
Degradation Products ◽  
Total Yield ◽  
Maximum Yield ◽  
Aspen Wood ◽  
Lignin Degradation Products ◽  
Phenolic Derivatives ◽  
Related Compounds ◽  
Soluble Lignin

The hydrogenolysis of aspen lignin using rhodium-on-charcoalas catalyst has been studied. The maximum yield of chloroform-soluble lignin degradation products was obtained at a reaction temperature of 195 °C. Analysis of this chloroform-soluble fraction revealed that the monomeric fraction was composed essentially of the four compounds, 1–4, only, and in a total yield representing at least 40% of the original lignin.Solvent extraction was shown to be preferred over thermal distillation as a preparative procedure for the separation of these phenolic derivatives. The significance of the isolation of these lignin degradation products is discussed.

STUDIES ON LIGNIN AND RELATED COMPOUNDS: I. A NEW METHOD FOR THE ISOLATION OF SPRUCE WOOD LIGNIN

1930 ◽  
Vol 2 (6) ◽  
pp. 357-363 ◽  
Author(s):  
Harold Hibbert ◽  
H. J. Rowley
Keyword(s):  
Hydrochloric Acid ◽  
Ethylene Glycol ◽  
Ethyl Ether ◽  
Cold Water ◽  
New Method ◽  
Large Excess ◽  
Spruce Wood ◽  
Hydroxy Compounds ◽  
Related Compounds ◽  
Unchanged Form

A description is given of a new method for the isolation from spruce meal of lignin in apparently a relatively unchanged form. The method consists in first extracting the spruce meal with a mixture of equal volumes of benzene and alcohol, followed by an extraction with water. The dried meal is then digested for 6–8 hr. at 110 °C. with 8–10 times its weight of ethylene glycol containing 0.2% of iodine, calculated on the weight of spruce meal taken. The reaction mixture is filtered, and the lignin isolated by pouring the filtrate into a large excess of cold water. Other catalysts such as hydrochloric acid may be used in place of iodine and the glycol may be replaced by a variety of hydroxy-compounds such as glycol mono-ethyl ether, glycerol, chlorhydrins, hydroxyacids, etc.

scholarly journals Avocado-Derived Biomass: Chemical Composition and Antioxidant Potential

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 100
Author(s):  
Minerva C. García-Vargas ◽  
María del Mar Contreras ◽  
Irene Gómez-Cruz ◽  
Juan Miguel Romero-García ◽  
Eulogio Castro
Keyword(s):  
Chemical Composition ◽  
Phenolic Content ◽  
Antioxidant Properties ◽  
Total Phenolic ◽  
Nutritional Properties ◽  
Aqueous Fraction ◽  
Extraction Solvent ◽  
Main Components ◽  
A Minor ◽  
Derivatives Of

Avocado has become fashionable due to its great organoleptic and nutritional properties. It is consumed as a fresh product and it is also processed to obtain salad oil and guacamole. In all cases, the only usable portion is the pulp. Therefore, to be a more sustainable and profitable agribusiness, it is important to recognize which compounds from the peel and the stone waste can be converted into valuable bio-products. Therefore, their chemical composition was determined according to the National Renewable Energy Laboratory, the total phenolic content by the Folin-Ciocalteu method and the antioxidant properties by the FRAP and TEAC assays. The main components of the peel and stone were acid-insoluble lignin (35.0% and 15.3%, respectively), polymeric sugars (23.6% and 43.9%, respectively), and the aqueous extractives (15.5% and 16.9%, respectively). Both biomasses contain lipids and protein, but a minor proportion (<6%). The valorization of lignin and sugars is of interest given the high content; stones are a rich source of glucose (93.2% of the polymeric fraction), which could be used to obtain biofuels or derivatives of interest. The extractive fraction of the peel contained the highest number of phenolic compounds (4.7 g/100 g biomass), mainly concentrated in the aqueous fraction (i.e., 87%) compared to the ethanol one, which was subsequently extracted. It correlated with major antioxidant activity and, therefore, the peel can be applied to obtain antioxidants and water can be used as an environmentally friendly extraction solvent.

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