ISOLATION OF FERULIC ACID FROM WHEAT BRAN HYDROLYZATE BY ADSORPTION

abstract

English

Together with maize and rice, wheat accounts for about 90 % of the world’s cereal production. Besides other valuable compounds such as wheat germ and endosperm parts, wheat bran remains a major byproduct during the milling process [1]. Wheat processing mills can produce up to 50 tons of bran per day. This waste material is suitable for further processing, as it still contains a significant proportion of phenolic compounds, especially ferulic acid. Ferulic acid is contained in bran in the form of feruloylated oligosaccharides [2]. The aim of this work was to develop a method for the isolation of ferulic acid from wheat bran. The research was divided into several segments. The first part of this work was focused on the pre­treatment of wheat bran. Wheat bran was subjected to protein removal to increase the purity of the final product. The next step in the process was to obtain the wheat bran hydrolysate to release ferulic acid into the solution. This step was realized by alkaline hydrolysis. This process was modified from the process described by Buranov [3]. Hydrolysis of bran was performed by 0,5 M NaOH in stirred, heated reactor with reaction time 4 hours at 50 °C with mixing at 180 rpm. After reaction, the solution was adjusted by the addition of 3M HCl to pH 3. A solid part of the mixture was separated by centrifugation. Supernatant after hydrolysis was subjected to isolation of ferulic acid by adsorption on amberlite XAD-16. The ratio of adsorbent to supernatant was 1 g to 150 ml. Adsorption was performed at pH 3 for 50 minutes with continuous stirring. Supernatant and adsorbent were further separated by 0,1 mm sieve. The adsorbent was rinsed by a solution of HCl with pH 3. Desorption of ferulic was the final step. It was made by mixing the adsorbent with 96% ethanol. Desorption was performed at laboratory temperature for 60 minutes with continued stirring at 150 rpm. Analysis of isolate was carried out by reversed phase HPLC on Shimadzu SCL-10 A with Kinetex 2.6 µm; C18; 100 × 4.60 mm column with 10 % acetonitrile and 90 % acetic acid (1% v/v) mobile phase. Based on the analyses, the efficiency of the whole process was evaluated. The amount of ferulic acid in the final isolate solution was 676 ± 57 mg/l. This is equal to yield 1,38 ± 0,27 g/kg ferulic acid from deproteinate wheat bran. The isolate does not contain only ferulic acid and solvent. The isolate can contain a variety of substances such as polysaccharides, proteins, salts or other phenolic substances. The main contaminant was identified as proteins (4,38 ± 1,16 g/l).

Wheatt bran, ferulic acid, adsorption, desorption, HPLC

NÁBĚLEK, J.; POŘÍZKA, J.; DIVIŠ, P.

25. 11. 2021

Vysoké učení technické v Brně, Fakulta chemická

Purkyňova 464/118, 612 00 Brno

978-80-214-6002-7

Studentská odborná konference CHEMIE JE ŽIVOT 2021 Sborník abstraktů

první

46

48

106

https://www.fch.vut.cz/vav/konference/sok/vystupy/sbornik-konference-2021-abstrakty-a5-pdf-p213391