Studies on the spectra of protoberberine alkaloids. I. Absorption spectrum of Berberine

Scientific paper - Original scientific paper

• Author: Z. Gašparec
• Author: K. Weber
• Author's institution: University of Zagreb; Faculty of Pharmacy and Biochemistry
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract (english)

Measurements have been made of the visible and UV
absorption spectra of berberine chloride in pure aqueous, methanol,
ethanol and propanol solutions and in the presence of various
concentrations of either hydrochloric acid or potassium hydroxide.
In all solutions, potassium hydroxide considerably influences
both the form of the absorption curves and the values of the extinction
coefficients. Bathochromic shifts (red s hift s) of the ab sorption
maxima were observed in the ultra-violet spectrum and
the disappearence of the absorption maxima in the visible.
It has been suggested that the addition of potassium hydroxide
causes the formation of the carbinolic form of berberine in all but
the aqueous solutions. The open carbinol form is probably formed
in the presence of l arge concentrations of KOH. It was found that
the shapes of the absorption curves of berberine in the presence of
KOH differ widely in different solvents .

• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Croatica Chemica Acta
• Numbering: vol. 37, no. 3, pp. 143-154
• p-ISSN: 0011-1643
• e-ISSN: 1334-417X
• URN:NBN: urn:nbn:hr:163:435121
• Publication: 1965
• Document URL: https://hrcak.srce.hr/208204
• Type of resource: Text
• Access conditions: Open access
• Created on: 2020-05-11 14:04:26