ISSN: 2456–5474 RNI No.  UPBIL/2016/68367 VOL.- VII , ISSUE- V June  - 2022
Innovation The Research Concept
Water Soluble Polysaccharides Obtained From Acacia Nilotica Linn. Seeds By Isolation, Purification and Preliminary Analysis
Paper Id :  16153   Submission Date :  2022-06-14   Acceptance Date :  2022-06-20   Publication Date :  2022-06-25
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Indra Pal Singh
Research Scholar
Chemistry
Agra College, Dr. Bhim Rao Ambedkar University
Agra,Uttar Pradesh, India
S.S. Khirwar
Associate Professor
Chemistry
Agra College, Dr. Bhim Rao Ambedkar University
Agra, Uttar Pradesh, India
Abstract
Acacia nilotica Linn provided the water soluble polysaccharide. Seeds were found to be constituted of D-galactose and D-mannose after acid hydrolysis with sulphuric acid, column and paper chromatographic examination. Acacia nilotica seeds were used to isolate polysaccharide. The alkaline hypoiodite approach provided water soluble sugars extract as D-galactose and D-mannose in a 1:4 molar ratio. Iodometrically, it consumed 1.06 moles of iodine. Paper chromatography was used to describe the monosaccharide produced, and column chromatography with a cellulose column was used to identify it. The primary polymer chain has (1→4) – β type and D-mannopyranose units, while the non-reducing ends have (1→6) – α – type linkage in D-galactopyranose units, which was validated by IR spectra. The melting points of sugar were discovered. Estimation of sulphated ash, optical rotations, and crystalline derivative preparation.
Keywords Seeds, Polysaccharides, D- galactose, D-mannose, Acacia Nilotica Plant.
Introduction
Polysaccharides, also known as polycarbohydrates, are the most common carbohydrate in foods. They are polymeric carbohydrates with lengthy chains made up of monosaccharide units linked together by glycosidic connections. They have a variety of structures, ranging from linear to heavily branching. Starch, glycogen, and galactogen are storage polysaccharides, while cellulose and chitin are structural polysaccharides. They can be amorphous or even water insoluble (Varki et al., 1999). When all of the monosaccharide in a polysaccharide is of the same kind, the polysaccharide is known as a homopolysaccharide or homoglycan; however, when more than one type of monosaccharide is present, the polymer is known as a heteropolysaccharide or heteroglycan. Acacia nilotica is a medium-sized tree that belongs to the Mimosoideae subfamily of the family Fabaceae or Leguminosae and was originally described by the Swedish botanist Carl Linnaeus (1773).The plant reaches a height of 15-18 meters and a diameter of 2-3 meters. The bark is typically salty green in young trees or practically black in mature trees, with large longitudinal fissures revealing the inner grey-pinkish slash and oozing a low-quality reddish gum. Bipinnate leaves have 3-10 pairs of pinnate, are 1.3-3.8 cm long, and have 10-20 pairs of leaflets that are 2-5mm long (Beniwal et al., 1992).Straight and thin In immature trees, light grey spines are found in axillary pairs, generally 3-12 pairs, 5-7.5 cm long, while older trees are often lacking thorns. Flowers in globule heads with a diameter of 1.2-1.5 cm and a beautiful golden yellow colour, born axillary or whorly on peduncles 2-3 cm long at the end of branches.Pods are 7-15 cm long, juvenile pods are green and tomentose, mature pods are greenish black, indehiscent, and tightly constricted between the seed, giving them a necklace look. Seeds are compressed, ovoid, and dark brown with firm testa, with 8-12 seeds per pod.Acacia Wild is a wide genus of trees, shrubs, and climbers that includes trees, shrubs, and climbers. Acacia species is one of the richest resources of bioactive flavonoids, alkaloids, phenolics, saponins, polysaccharides, tannins, and terpenoid. Different species of Acacia have been reported, but only a few of these find medicinal importance out of which the prominent ones are: 1. Acacia nilotica 2. Acacia polycantha 3. Acacia Leucophala 4. Acacia farnesiana 5. Acacia leucophloea 6. Acacia sinuata 7. Acacia ferruginea 8. Acacia catechu.
Objective of study
Polysaccharides derived from plant foods are major components of the human diet, with limited contributions of related components. The structure and distribution, their modification during food processing and effects on functional properties, The behavior in the gastrointestinal tract, and their contribution to healthy diets.
Review of Literature
The carbohydrate components of the human diet are derived almost exclusively from plant sources and play crucial roles in food processing and in diet and health.
Methodology
Isolations of Polysaccharide- The seeds of the Acacia nilotica were cleaned and dried completely. In a manual grinder, the seeds were split into a yellowish grey powder at a low speed. The pulverized seeds (100 gm) were steeped overnight and stirred for 48 hours in distilled water (900 ml, 600).To eliminate the insoluble substance that was present in the solution; the viscous solution was pressed through muslin cloth. As previously, soluble matter was treated with water (1:1) to extract additional polysaccharide. To remove finely suspended particles, the fluid was centrifuged at 25,000 rpm in a Sharple super centrifuge. After centrifugation, the centrifugate was treated with ethanol (2:1) to precipitate the polysaccharide in the fasces. Under suction, the polysaccharide precipitate was filtered via a sintered funnel (G-3) the wet polysaccharide was triturated with ethanol and filtered in the same manner as the dry polysaccharide. After washing with acetone and ether, the polysaccharide was dried in a vacuum at 60 degrees. The polysaccharide was obtained as a grey solid mass (8 gram) with 1.05 percent sulphated ash. Purification- To make a barium complex, the polysaccharide solution in water was treated with barium hydroxide. The original polysaccharide was released when the barium complex was decomposed with acetic acid, although it had a greater amount of sulphated ash (4.2 percent) than the original polysaccharide. As a result, fractional precipitation with ethanol was used to purify the polysaccharide. 4.95 gram crude polysaccharide was dissolved in water (2:1) for 12 hours with continual mechanical stirring to achieve a 2% concentration solution. Ethanol was gradually added to the water soluble polysaccharide to achieve a concentration of ethanol in the solution of up to 20%. Some contaminants were precipitated as a result of this. The resulting centrifugate was treated with ethanol at 40 percent and subsequently 60 percent concentrations, resulting in full polysaccharide precipitation. The polysaccharide produced at 40 and 60 percent ethanol concentrations was triturated three to four times with absolute ethanol, acetone, and ether before being dried in vacuo at 600. When these two polysaccharide fractions were exposed to infrared spectroscopy with KBr pallets, the spectrograms were identical.
Analysis

Preliminary Analysis  

The polysaccharide had (α)D25 +28.20(H2O) for 40% and (α)D25+28.90(H2O) for 60% respectively. This process was again repeated to get homogenous polysaccharide. The optical rotations of the pure polysaccharide were obtained as follows - (α)D25 +28.20(H2O) for 40% and (α)D25+28.90(H2O) for 60%, thus indicating that the two polysaccharide are identical homogenous which was confirmed by their identical infrared spectrum. The polysaccharide obtained was in the form of a grey amorphous powder, did not reduce Fehling solution. N, S, C2H3o, uronic acid halogens groups were absent. It formed a highly viscous solution in water.

Result and Discussion

Result of Iodometric Titrations During Hydrolysis
After regular intervals of time, a portion of the hydrolysis (1 ml) was pipetted into the iodine flask and neutralized with sodium hydroxide solution (1N) using phenolpthlene as an indicator. To the neutralized solution, add iodine solution (0.1N, 5 ml) and sodium hydroxide solution (0.1N, 10 ml), mix well, and set aside for 20 minutes. Excess iodine was titrated against sodium thio-sulphate solution after the combination was acidified with H2SO4 (2N, 25ml) (0.1N). A blank was likewise ran in the same way. Table 1 shows the rate of hydrolysis of the polysaccharide with H2SO4 (72%) followed by  H2SO(1N) as shown in table 1
Course of acid hydrolysis of the Acacia nilotica Linn seeds polysaccharide

S. No

Time (hours)

Hypo required (ml)

      Iodine consumed

(Calculated on the basis of hypo consumption)

 

Remarks

1

2

3

4

5

6

7

8

00

12

14

16

18

20

22

24

4.12

3.40

3.24

3.12

3.10

3.08

3.06

3.06

0.00

0.72

0.68

1.00

1.02

1.04

1.06

1.06

Hydrolysis with H2SO4 (72%) at R.T.

 

Further hydrolysis with H2SO4(1N) at 1000C

 

 

The hydrolysis process could not be tracked by measuring optical rotations at regular intervals. The optical rotation of the fully hydrolyzed product, on the other hand, was determined to be(α)D25+35.9. (Acid solution).The hydrolyzate was neutralized using barium carbonate slurry. During neutralization, the contents were well mixed and stored overnight. Filtration was used to extract the unreacted barium carbonate and barium sulphate from the solution, and the residue was washed three times with water, then again with hot water. The solution (filtrate and washing) was passed through regenerated Amberlite IR-120(H+) and Amberlite IR-45 (OH-) and concentration to thin syrup. Paper chromatography examination using solvent (A) and spray reagent (A) reveals the presence of D- galactose and D-mannose only.
Identification of Sugar Paper Chromatography
The identification of sugar mixture by paper chromatography analysis at the hydrolysis with descending technique on whatman No. 1 filter paper sheet. The mixture solvent used for the detection of sugar as (A) n- butanol. Ethanol, water,(4:1:5 uppaer phase) and used p-anisidine phosphate as spray reagent to reaveald the presence of D- glucose and D-mannose. 
Resolution of Sugars by Column Chromatography
In a glass tube (55x2cm) equipped with a glass stopper, a column was produced using whatman standard cellulose powder. A thin uniform coating of glass wool was placed at the bottom of the column after the glass tube was properly cleaned and dried. Medium-sized cellulose power slurry was made by mixing the solvent, butan-1-ol half-saturated with water, for a few minutes in a blender. The slurry was placed into a half-filled glass column with the solvent. The cellulose powder was allowed to settle at the bottom of the column (13"), with caution given not to allow the column to dry out, as this would result in air bubbles forming and the packing operation having to be repeated. For a 30 cm long column, 25gm of cellulose powder was adequate. The eluting solvent, butan-1-ol, was half saturated with water and washed the column until it was colourless.The movement of methyl red dye was used to verify the column's homogeneity. To thoroughly remove the colour, the column was washed again using the same solvent. With the assistance of a bent pipette, thin syrup (4 ml) of the sugar combination was injected into the column and allowed to drain into the cellulose column by gravity.The sidewalls of the column above the cellulose were filled with about 10 ml of the eluting solvent.Using a constant head reservoir system, the solvent was allowed to trickle down. The elutes were collected in 10 ml portions manually. The fractions were examined by paper chromatography and found to contain the sugar as shown in table 2.
Table - 2
Resolution of Sugar Mixture on Cellulose Column

Fraction No.

Sugar present

1-39

40-60

61-73

74-100

100 and above

No sugar

D-mannose only

Mixture of D-mannose and D-galactose

D-galactose only

No sugar

 

Characterization of Sugars
Appropriate fraction of the elute containing single pure sugar were combined together and concentrated. D-galactose and D-mannose were identified as follows –
D-galactose, m.p. and mixed m.p. 165-166o..                                       
(α)D28 + 81.9 0 (C, 0. 47 H20)
D-mannose, m.p.  And mixed m.p.  129 -130o.
(α)D28 + 12.0o   (C, 1.29 H20).
In a flask, there was a 25 ml aqueous solution of D-galactose. The mixture was shaken after adding 10 drops of glacial acetic acid and 5 drops of phenyl hydrazine. Fit the cork loosely into the flask and place it in a boiling water bath for 10 minutes, shaking it occasionally-galactose phenyl-hydrazone precipitated as a thick brownish yellow precipitate. It was dried after recrystallization with ethanol. In the same way, a phenyl hydrazone derivative of D-mannose was made. D-galactose phenyl hydrazone, m.p. and mixed m.p. 173o. D-mannose phenyl hydrazone, m.p.  and mixed m.p. 197o.
Quantitative Estimation of Sugar
For quantitative sugar estimation, the polysaccharide (280 mg) was heated in a sealed tube at 1000 for 26 hours over a boiling water bath with sulphuric acid (1N, 10ml) and processed as normal. In solvent, the hydrolyzate was separated on a sheet of Whatman filter paper No. 1 sheet (A).With the aid of a guide spot, areas of the paper containing a single sugar component were cut off and sugar was eluted with water using Dent's technique’s-galactose and D-mannose eluted solutions (5 mL each) were maintained separate in 50 mL standard joint flasks. Stoppard solutions of sodium metaperiodate (0.25M, 1ml) were added to each of the sugar solutions. The D-galactose solution was refluxed for 40 minutes on a hot water bath, while the D-mannose solution was refluxed for 20 minutes. To eliminate the surplus sodium metaperiodate, the flasks were cooled and ethylene glycol (0.2 ml) was added to each flask. Using methyl red as an indicator, the librated formic acid was triturated with sodium hydroxide solution (0.01N) (free of carbon dioxide).In pure polysaccharide, the ratio of D-galactose to D-mannose was determined to be 1:4.2.

Conclusion
Polysaccharides consisting of one type of sugar unit uniformly linked in linear chains are usually water insoluble even when the molecules have a low molecular weight with degrees of polymerization. An exception to the rule (1→6) homoglycans. The seeds yielded a water soluble polysaccharide as D- galactose and D-mannose in molar ratio 0f 1:4 determine by alkaline hypoiodite method, the indicating polysaccharide was a galactomannan. Iodine consumed 1.06 moles by iodometrically. Polysaccharide was characterized to specify by paper and column chromatography. The nature of the linkage with polysaccharide was obtained from in infrared spectra. The β-type linkage in D-mannopyranose units in the main polymer chain of Acacia nilotica Linn seeds polysaccharides. The prepared monosaccharide derivatives by usual manner as D-galactose phenyl hydrazone and D- mannose phenyl hydrazone.
Acknowledgement The authors are highly thankful to my honorable supervisor Dr. S.S.Khirwar (Associate Professor) department of Chemistry and Principal Dr. Anurag shukala Agra College Agra for providing necessary facilities.
References
1. Varki, A., Cummings, R., Esko, J., Freeze, H., Hart, G., & Marth, J. (1999). Essentials of Glycobiology Cold Spring. 2. Narayan, D. P., & Purohit, S. S. (2004). Agro’s colour atlas of medicinal plants. India Agrobios, 3. 3. Joy, P. P., Thomas, J., Mathew, S., & Skaria, B. P. (1998). Medicinal plants, kerala agricultural university. Aromatic and Medicinal Plants Research Station, 4-6. 4. Dymock, W., Warden, C. J. H., & Hooper, D. (1893). Pharmacographia Indica: A history of the principal drugs of vegetable origin, (Vol. 1). New Delhi Shrishti book distributors 2005, 556. 5. Seigler, D. S. (2003). Phytochemistry of Acacia—sensu lato. Biochemical systematics and ecology, 31(8), 845-873 6. Rafique, C. M., and F. Smith. "The Constitution of Guar Gum1." Journal of the American Chemical Society 72.10 (1950): 4634-4637. 7. Hirst, ELt, and J. K. N. Jones. "359. Quantitative analysis of mixture of sugars by the method of partition chromatography. Part III. Determination of the sugars by oxidation with sodium periodate." Journal of the Chemical Society (Resumed) (1949): 1659-1662. 8. Dent, C. E. "A study of the behaviour of some sixty amino-acids and other ninhydrin-reacting substances on phenol-collidine'filter-paper chromatograms, with notes as to the occurrence of some of them in biological fluids." Biochemical Journal 43.2 (1948): 169. 9. Singh, Rb, and VK Jindal. "Polysaccharide from Cassia Javanica Seeds. Isolation, Purification and Preliminary analysis of Polysaccharide." Polish Journal of Chemistry 61.7-12 (1987): 805-809. 10. Miller, Foil A. "Chemical Technology: Chemical Applications of Infrared Spectroscopy. CNR Rao. Academic Press, New York, 1963. xiv+ 683 pp. Illus. $19.50." Science 144.3625 (1964): 1441-1441. 11. Neiderl, J. S., and V. Neiderl. "Methods in Quantitative Analysis." New York (1948): 25. 12. Anderson, D. M. W., and J. F. Stoddart. "Studies on uronic acid materials: Part XV. The use of molecular-sieve chromatography in studies on acacia senegal gum (Gum Arabic)." Carbohydrate Research 2.2 (1966): 104-114. 13. Hamilton, J. K., and E. G. V. Partlow. "Acid hydrolysis of Gaur gum polysaccharide." J. Am. Chem. Soc 80 (1958): 4880-4882. 14. Baker, Julian Levett, and Henry Francis Everard Hulton. "The iodimetric estimation of sugars." Biochemical Journal 14.6 (1920): 754. 15. Singh, R. B. "Structure of aldobiouronic acid and glucuronic acid from Agathis australis degraded gum polysaccharide." Journal of environmental biology 28.2 (2007): 163.