Decolorization of synthetic and natural melanoidins by ultrafiltration using cellulose acetate membranes

Date

10-1997

Degree

Bachelor of Science in Chemistry

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Ernesto J. Del Rosario

Abstract

Synthetic melanoidin was prepared from equimolar concentrations of glucose and glycine, and compared with natural melanoidin obtained from alcohol distillery biodigester effluent. The average molecular weights for synthetic and natural melanoidin were 42.62 -I 3.8 Id) and 35.62 ± 3.2 kD, respectively by Sephadex gel chromatography. Both synthetic and natural melanoidins were decolorized by ultraffltration (UF) through cellulose acetate (CA) membranes which had been prepared from nata de coco (bacterial cellulose); the CA concentrations in the polymer (dope) mixture were 19, 23 and 25 %. Maximal decolorization values were obtained at 25% CA concentration of the membrane; these were 73.76 ± 2.4% for synthetic and 93.77 ± 0.6% for natural melanoidin. The highest relative increase in absorbance of the retentate, which is proportional to melanoidin concentration, were also obtained at 25% CA concentration with values of 12.06± 0.9% and 26.65 ± 0.1% for synthetic and natural melanoidin, respectively. The effect of increasing CA concentration of the solutions used in the preparation of the membranes on the extent of melanoidin decolorization is attributed to the decrease in membrane pore size. The experimental results were discussed on the basis of the pore flow and solution-diffusion theories of ultrafiltration.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

Thesis

Document Type

Thesis

This document is currently not available here.

Share

COinS