- Title
- A preliminary investigation of the structure of green wattle tannin (acacia decurrens willd)
- Creator
- Glueck, Leonard David
- ThesisAdvisor
- Roux, D.G.
- Subject
- Tannins
- Subject
- Tannin plants
- Date
- 1952
- Type
- Thesis
- Type
- Masters
- Type
- MSc
- Identifier
- vital:4475
- Identifier
- http://hdl.handle.net/10962/d1011988
- Identifier
- Tannins
- Identifier
- Tannin plants
- Description
- Green wattle tannin extracts were separated by lead salt precipitation into a phenolic tannin fraction and a nontannin fraction. The combustion analysis of the tannin fraction corresponded to an empirical formula C₁₅H₁₄O₆. Methoxy and acetyl values showed four oxygens were hydroxy groups while the residual oxygens could either be ether linked or carbonyl groups. Diazomethane methylation produced a white product of high methoxyl value which indicated that the four hydroxyl groups were phenolic. Chromatography of the lead salt purified tannin showed an indistinct non-fluorescent trail. Ether extraction of the tannin removed the associated Phenolic bodies. The ethereal extract unlike black wattle extracts contained no fisetin and evaporation of the ethereal solutions yielded a gummy non-crystalline residue. Alkaline fusion of the purified tannin produced for the first tlme a variety of acidic and phenolic compounds i.e. resorcinol, pyrogaloll, phloroglucinol β-resorcylic acid, gallic acid and protocatechuic acid. From the high yields of resorcinol (6%) and gallic acid (3%), these units appear to predominate. These degradation productions, coupled with the analytical figures, indicate a possible C₁₅ unit with resorcinol and pyrogallol nuclei as a basis. The non-tannin fraction failed to reveal any compound which might cause the excessive redness in green wattle extracts. Chromatography of this non-tannin fraction showed the presence of sucrose.
- Format
- 70 p., pdf
- Publisher
- Rhodes University, Faculty of Science, Chemistry
- Language
- English
- Rights
- Glueck, Leonard David
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