Thesis (M.Sc. (Biochemistry))--Mahidol University, 1976.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 86-98). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (p. 88-93).

Thesis (M.S.)--Oregon State University, 1985. / Typescript (photocopy). Includes bibliographical references (leaves 98-105). Also available on the World Wide Web.

A number of interrelated flavonoid compounds, present in trace quantities in mature black wattle (Acacia mearnsii De Wild) bark, have been isolated and identified for the first time. They include a) the resorcinol-pyrogallol analogues, (+)-leuco-robinetinidin (7,5',4',5'-tetrahydroxyflavan-3,4-diol), dihydrorobinetin (7,5',4',5'-tetrahydroxyflavan-3-ol-4-one) and robtein (2',4',5,4,5- pentahydroxychalcone) and b) the resorcinol-catechol analogues, (+)-leuco-fisetinidin (7,3',4'-trihydroxyflavan-3,4-diol), fustin (7,3',4'-trihydroxyflavan-3-ol-4-one), (-)-fisetinidol (7,3',4'trihydroxyflavan- 3-ol), butein (2',4',3,4-tetrahydroxychalcone) and butin (7,5',4'-trihydroxyflavan-4-one). In addition, two flavonol glycosides, myricitrin (3,5,7,3',4',5'-hexahydroxyflavone-3-rhamnoside ) and quercitrin (5,5,7,5',4'-pentahydroxyflavone-3-rhamnoside), which belong to the phloroglucinol-pyrogallol and phloroglucinolcatechol class of flavonoids respectively, were isolated from immature bark. These represent the only glycosides isolated hitherto from wattle bark or heartwood extracts. Summary, p. i.

No description available.

No description available.

Apart from their general usage as tanning agents for hides and skins, the natural tannins have been used since earliest times for various other purposes. The blue-black iron tannate complex was used by ancient Egyptians as a hairdye and for many conturies this complex was the main source of writing inks. Wattle tannin is known to form complexes with many metal ions. The chief use of tannin complexes has been in gravimetric analyses, since aqueous solutions of tannins readily precipitate metal ions under certain experimentel conditions. At the present time the nature of the precipitated complexes has not been investigated however, because in the gravimetric method the complexes are ignited and the metal determined as its oxide; hence no knowledge of the complexes themselves was required.

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.

The purpose of this paper is to investigate three California oaks as possible sources of tannin. Even though the study of the three varieties of tree may not be representative samples, the procedures developed may prove to be valuable in a more extensive research by other workers.