Polysaccharides of tropical pasture herbage. IV. A pectic acid from Townsville lucerne (Stylosanthes humilis)

1971 ◽  
Vol 24 (5) ◽  
pp. 1049 ◽  
Author(s):  
M Alam ◽  
GN Richards
Keyword(s):  
Phosphate Buffer ◽  
Galacturonic Acid ◽  
Sodium Acetate ◽  
Structural Characteristics ◽  
Small Extent ◽  
Partial Hydrolysis ◽  
Tropical Pasture ◽  
Pectic Acid ◽  
Stylosanthes Humilis

Pectic acid, extracted from the stems of Townsville lucerne in 4% yield, has been fractionated by precipitation with sodium acetate. The product contains two components as revealed by electrophoresis in phosphate buffer, but the major structural characteristics have been determined by partial hydrolysis. The pectic acid is esterified to a very small extent (1% OCH3) and consists predominantly of 1,4-a-linked D-galacturonic acid units with L-arabofuranose units as the major neutral constituent.

A STUDY OF THE PECTIN PRESENT IN THE BARK OF AMABILIS FIR (ABIES AMABILIS)

1965 ◽  
Vol 43 (4) ◽  
pp. 758-765 ◽  
Author(s):  
S. S. Bhattacharjee ◽  
T. E. Timell
Keyword(s):  
Galacturonic Acid ◽  
Structural Formula ◽  
Partial Hydrolysis ◽  
Side Chains ◽  
Pectic Acid ◽  
Abies Amabilis ◽  
Conventional Fractionation ◽  
Glycosidic Bonds ◽  
First Time ◽  
Pectic Material

A pectic material has been isolated from the bark of Abies amabilis (Dougl.) Forbes in a yield of 2%. On hydrolysis it yielded D-galacturonic acid, D-galactose, and L-arabinose in a ratio of 85:4:11, and also traces of rhamnose. The product, when submitted to several conventional fractionation methods, appeared homogeneous. Further resolution could be effected by acidification of an aqueous solution of the pectin, followed by ultracentrifugation. The insoluble portion (50%) was an electrophoretically homogeneous galacturonan with [α]D + 246°. The material remaining in solution (30%), here referred to as a pectic acid, had [α]D + 225° and on hydrolysis gave D-galacturonic acid, D-galactose, and L-arbabinose in a ratio of 74:7:19, as well as traces of rhamnose.The structure of the galacturonan was established by partial hydrolysis and methylation. It consisted of α-D-galacturonic acid residues linked together by (1 → 4)-glycosidic bonds to a linear macromolecule. The same techniques were applied to the pectic acid. While a unique structural formula could not be assigned in this case, one probable alternative involved a framework of (1 → 4)-linked α-D-galacturonic acid residues together with a few residues of 1,2,4-linked L-rhamnose. Some of the galacturonic acid units carried at C-2 and C-3 side chains which were terminated by D-galactopyranose and L-arabinofuranose residues. A few of the latter also occurred as inner units, probably in the side chains. This appears to be the first time a pectic material has been resolved into a galacturonan and a pectic acid containing the four sugar residues usually found in pectins. It is probable that the pectin occurring to a limited extent in wood has a similar composition.

scholarly journals Novel Antioxidant and Hypoglycemic Water-Soluble Polysaccharides from Jasmine Tea

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2375
Author(s):  
Yayuan Tang ◽  
Jinfeng Sheng ◽  
Xuemei He ◽  
Jian Sun ◽  
Zhen Wei ◽  
...  
Keyword(s):  
Galacturonic Acid ◽  
High Performance ◽  
Structural Characteristics ◽  
Gel Permeation Chromatography ◽  
Helical Structure ◽  
Water Soluble ◽  
Nuclear Magnetic Resonance Analysis ◽  
Molar Ratios ◽  
Jasmine Tea

There have been few studies dealing with chemical elucidation and pharmacological potentials of water-soluble polysaccharides from jasmine tea, limiting their use in functional foods. In this study, water-soluble polysaccharides (named as JSP) were extracted from Jasminum sambac (L.) Aiton tea and fractionated to afford two sub-fractions (JSP-1 and JSP-2). The main structural characteristics of novel JSP sub-fractions were determined by high performance gel permeation chromatography, ultra-performance liquid chromatography-tandem mass spectrometry, Fourier transform infrared, and nuclear magnetic resonance analysis. Physiologically, the abilities of JSP-1 and JSP-2 to reduce ferric ions, scavenge DPPH and hydroxyl radicals, as well as protect islet cells were confirmed in vitro. JSP-1 exhibited better antioxidant and hypoglycemic activities than JSP-2. The molecular weights of JSP-1 and JSP-2 were 18.4 kDa and 14.1 kDa, respectively. JSP-1 was made up of glucose, galactose, rhamnose, xylose, arabinose, and galacturonic acid with molar ratios 1.14:4.69:1.00:9.92:13.79:4.09, whereas JSP-2 with a triple helical structure was composed of galactose, rhamnose, xylose, arabinose, and galacturonic acid as 3.80:1.00:8.27:11.85:5.05 of molar ratios. JSP-1 contains →1)-α-Galƒ-(3→, →1)-α-Galƒ-(2→, →1)-α-Araƒ-(5→, →1)-α-Araƒ-(3→, →1)-α-Araƒ-(3,5→, →1)-β-Xylp-(2→ and →1)-β-Xylp-(3→ residues in the backbone. These results open up new pharmacological prospects for the water-soluble polysaccharides extracted from jasmine tea.

STRUCTURE OF A GALACTURONAN FROM SUNFLOWER PECTIC ACID

1966 ◽  
Vol 44 (11) ◽  
pp. 1275-1282 ◽  
Author(s):  
V. Zitko ◽  
C. T. Bishop
Keyword(s):  
Galacturonic Acid ◽  
Periodate Oxidation ◽  
Degree Of Polymerization ◽  
Critical Assessment ◽  
Molar Ratio ◽  
Aqueous Methanol ◽  
Pectic Acid ◽  
Potassium Borohydride ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of

Fractions of sunflower pectic acid containing 89.8%, 94.2%, and 91.4% of D-galacturonic acid were carboxyl reduced as their methyl or ethylene glycol esters by potassium borohydride. Critical assessment of the effects of three different solvents (water, 80% aqueous dimethyl sulfoxide, and 80% aqueous methanol) on the efficiency of reduction showed that the latter solvent was best. The reductions caused a decrease in the degree of polymerization from 270 to 21. Measurement of the rates of hydrolysis of partially reduced pectic acids containing 90%, 41.6%, 19.9%, 11.0%, and 0.65% of D-galacturonic acid showed that the rate of hydrolysis was directly related to the proportion of galacturonosidic linkages present. Methylation and hydrolysis of the carboxyl-reduced pectic acid fractions yielded 2,3,4,6-tetra-O-methyl-D-galactose and 2,3,6-tri-O-methyl-D-galactose in an approximate molar ratio of 1:20. Results of the periodate oxidation of the carboxyl-reduced pectic acid supported the conclusion inferred from the methylation results that the pectic acid was a linear polymer of 1 → 4 linked α-D-galacturonic acid units.

SOME CHARACTERISTICS OF BRAIN TYROSINE HYDROXYLASE

1967 ◽  
Vol 45 (10) ◽  
pp. 1557-1563 ◽  
Author(s):  
E. G. McGeer ◽  
S. Gibson ◽  
P. L. McGeer
Keyword(s):  
Tyrosine Hydroxylase ◽  
Rat Brain ◽  
Phosphate Buffer ◽  
Sodium Acetate ◽  
Acetate Buffer ◽  
Sodium Acetate Buffer ◽  
Optimum Conditions ◽  
Hydroxylase Activity ◽  
Michaelis Constant ◽  
Brain Tyrosine Hydroxylase

Tyrosine hydroxylase from brain homogenates differed from tyrosine hydroxylase from adrenal homogenates in being particle-bound, insensitive to cofactors, possessing a lower Michaelis constant for tyrosine, and being responsive to slightly different optimum conditions of pH and buffer. The combination of 0.02 M mercaptoethanol and 0.1–1.0 mM 2-amino-4-hydroxy-6,7-dimethyltetrahydropteridine (DMPH4) increased tyrosine hydroxylase activity in beef adrenal homogenates 15-fold, but was without effect on activity in rat brain homogenates. The Km for tyrosine in beef adrenal homogenates was 4 × 10−6 M, and in rat brain homogenates was 0.45 × 10−6 M. Conversion in beef adrenal homogenates was maximum in 0.6 M sodium acetate buffer, pH 6.0, and in rat brain homogenates was maximum in 0.28 M phosphate buffer, pH 6.2.

The sodium concentration in some tropical pasture species with reference to animal requirements

1970 ◽  
Vol 10 (42) ◽  
pp. 32
Author(s):  
MJ Playne
Keyword(s):  
Dry Matter ◽  
Sodium Concentration ◽  
Grass Species ◽  
Panicum Maximum ◽  
Tropical Pasture ◽  
High Sodium ◽  
Heteropogon Contortus ◽  
Stylosanthes Humilis ◽  
Chloris Gayana ◽  
Low Levels

A survey was made of the sodium concentration in eight grass and legume pasture species in the Townsville region. The grass species could be characterized according to sodium concentration. Panicum maximum, Chloris gayana, and Cenchrus setigerus were 'high-sodium' species (>0.40 per cent Na), whereas Urochloa mosambicensis had a medium sodium concentration, and Cenchrus ciliaris, Heteropogon contortus, and the legumes Stylosanthes humilis and Phaseolus atropurpureus were `low-medium� species (<0.10 per cent Na). The sodium concentration in five species grown at five sites located within 257 kilometres of Townsville, Queensland, was also examined at one stage of growth. Since several common pasture species contained low levels of sodium (<0.05 per cent of dry matter) deficiency symptoms could occur in grazing stock under certain circumstances.

Large-scale preparation of α-D-(14)-oligogalacturonic acids from pectic acid

2002 ◽  
Vol 80 (8) ◽  
pp. 900-903 ◽  
Author(s):  
Hong-Ni Fan ◽  
Mei-Zheng Liu ◽  
Yuan C Lee
Keyword(s):  
Galacturonic Acid ◽  
Large Scale ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Size Exclusion ◽  
Inexpensive Method ◽  
Pectic Acid ◽  
Large Scale Preparation ◽  
Exclusion Chromatography ◽  
Scale Preparation

An efficient and inexpensive method for large-scale preparation of α-D-(1[Formula: see text]4)-oligogalacturonic acids (oligo-GalA), up to DP 5, from pectic acid is described. Pectic acid was digested with a commercially available pectinase to yield a mixture of oligo-GalA, which was effectively separated by a combination of low-pressure – size-exclusion chromatography based on ion-exchange chromatography to obtain pure oligo-GalA of DP 2-5. Key words: pectic acid, galacturonic acid, galabiose, galatriose, pectinase.

Lemon-peel pectin. III. Fractionation of pectic acids from lemon-peel and lucerne

1970 ◽  
Vol 48 (8) ◽  
pp. 1290-1295 ◽  
Author(s):  
G. O. Aspinall ◽  
I. W. Cottrell ◽  
J. A. Molloy ◽  
M. Uddin
Keyword(s):  
Sodium Acetate ◽  
Single Component ◽  
Pectic Acid ◽  
Lemon Peel

The pectic acids formed on saponification of lemon-peel pectins C and L have been fractionated by graded precipitation with sodium acetate. The results of analytical and electrophoretic studies on the pectic acid fractions have been interpreted as being typical of those of the fractionation of chemically homogeneous polydisperse systems. Similar fractionations of lucerne polysaccharides have indicated the presence of a single component in pectic acid A and of two components in pectic acid B. The nature of polysaccharide heterogeneity in pectic acid preparations is discussed.

Polysaccharides of tropical pasture herbage. III. The distribution of the major polysaccharide components of Townsville lucerne (Stylosanthes humilis) during growth

1971 ◽  
Vol 24 (5) ◽  
pp. 1041 ◽  
Author(s):  
CP Way ◽  
GN Richards
Keyword(s):  
Gas Chromatography ◽  
Medicago Sativa ◽  
Monosaccharide Composition ◽  
Tropical Pasture ◽  
Stages Of Growth ◽  
Pasture Legumes ◽  
Pectic Substances ◽  
Stylosanthes Humilis ◽  
Stem Leaf ◽  
Pasture Legume

Stylosanthes humilis, the predominant pasture legume in North Queensland, has been collected at three different stages of growth, viz. flowering, seeded, and senescence. The plants have been divided into stem, leaf, root, seed, and pod and each fraction has been analysed for the following types of polysaccharide components: water- solubles, pectic substances, hemicelluloses, and cellulose. The absolute monosaccharide composition of each of these fractions has been determined by hydrolysis and gas chromatography. Most of the polysaccharide components are similar in nature to those previously found in temperate pasture legumes (e.g. Medicago sativa), but the seeds are unusual among legumes in containing no galactomannan and there is evidence of the presence of a glucomannan in all parts of the plant.

Extracellular polysaccharides from suspension-cultured sycamore cells

1969 ◽  
Vol 47 (11) ◽  
pp. 1063-1070 ◽  
Author(s):  
G. O. Aspinall ◽  
J. A. Molloy ◽  
J. W. T. Craig
Keyword(s):  
Galacturonic Acid ◽  
Culture Medium ◽  
Extracellular Polysaccharides ◽  
Partial Hydrolysis ◽  
Side Chains ◽  
Acer Pseudoplatanus ◽  
Enzymic Hydrolysis ◽  
Glucan Chain ◽  
Coniferous Woods

Three polysaccharides have been isolated from the culture medium of suspension-cultured sycamore cells (Acer pseudoplatanus L.). A pectinic acid which contains 67% of galacturonic acid residues has been shown to have features in common with other pectins, with arabinose, galactose, and rhamnose as constituent sugars. Methylation and partial hydrolysis have indicated that the arabinogalactan is similar to those from coniferous woods in containing a highly branched framework of D-galactopyranose residues mutually joined by (1 → 3) and (1 → 6) linkages with the majority of side chains terminated by L-arabinofuranose residues. A fucoxyloglucan has been shown by methylation and enzymic hydrolysis to possess a structure similar to those of the so-called seed 'amyloids' with a cellulose-like (1 → 4)-linked β-D-glucan chain with side chains terminated by L-fucopyranose and D-xylopyranose residues.

Correction - The sodium concentration in some tropical pasture species with reference to animal requirements

1970 ◽  
Vol 10 (42) ◽  
pp. 32
Author(s):  
MJ Playne
Keyword(s):  
Dry Matter ◽  
Sodium Concentration ◽  
Grass Species ◽  
Panicum Maximum ◽  
Tropical Pasture ◽  
High Sodium ◽  
Heteropogon Contortus ◽  
Stylosanthes Humilis ◽  
Chloris Gayana ◽  
Low Levels

A survey was made of the sodium concentration in eight grass and legume pasture species in the Townsville region. The grass species could be characterized according to sodium concentration. Panicum maximum, Chloris gayana, and Cenchrus setigerus were 'high-sodium' species (>0.40 per cent Na), whereas Urochloa mosambicensis had a medium sodium concentration, and Cenchrus ciliaris, Heteropogon contortus, and the legumes Stylosanthes humilis and Phaseolus atropurpureus were `low-medium� species (<0.10 per cent Na). The sodium concentration in five species grown at five sites located within 257 kilometres of Townsville, Queensland, was also examined at one stage of growth. Since several common pasture species contained low levels of sodium (<0.05 per cent of dry matter) deficiency symptoms could occur in grazing stock under certain circumstances.

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