The effect of enzymatic hydrolysis on the biological properties of Oenothera biennis,Borago officinalis and Nigella sativa seedcake by‐products from oil pressing

Abstract

The biological properties of ethanolic (50%, v/v) extracts from Oenothera biennis, Borago officinalis, Nigella sativa seedcake before and after enzymatic hydrolysis by alpha-amylase (EC 3.2.1.1) from Aspergillus oryzae, beta-glucosidase (EC 3.2.1.21) and beta-glucanase (EC 3.2.1.6) from Aspergillus niger combinations in a ratio of 1:1:1 were investigated. Total phenolic, flavonoid and reducing sugar content for O. biennis extract after enzymatic hydrolysis was, respectively, 0.5, 1.5 and 2 times higher in comparison with nonhydrolysed extract. Iron-chelating and O À 2 radical-scavenging activity of O. biennis seedcake extract after hydrolysis (IC 50 = 0.076 mg mL À1 and IC 50 O À 2 = 0.050 mg mL À1 ) was at a similar level as that nonhydrolyeed (IC 50 = 0.070 mg mL À1 and IC 50 O À 2 = 0.065 mg mL À1 ). The antioxidant activity was two times higher after hydrolysis than before enzymatic hydrolysis of O. biennis seedcake extract. Also strong elastase inhibition activity has been shown to O. biennis seedcake extract before (IC 50 = 0.095 mg mL À1 ) and after enzymatic hydrolysis (IC 50 = 0.07 mg mL À1 ), respectively. Oenothera biennis and B. officinalis seedcake extracts before and after hydrolysis have stronger antibacterial activity against Pseudomonas aeruginosa strain in comparison with N. sativa seedcake.

Evaluation of antioxidant and antimicrobial properties of enzymatically hydrolysed Cucurbita pepo and Linum usitatissimum seedcakes

“…Data represent the mean values±standard deviation of six independent experiments, each performed in triplicate. Student's t-test: p<0.05. enzymatic hydrolysis on the antioxidant properties of O. biennis, B. officinalis and N. sativa seedcakes (6,14). The present study confirms that the seedcake extracts have strong antioxidant activity and the hydrolysis of glycosidic forms of polyphenols affect on the growth of their antiradical capacity.…”

“…Al-Ghazal (35) observed that the methanolic extracts of C. pepo fruitcortex have antimicrobial activity against S. aureus and E. coli, respectively whereas the aquous extract was effective against S. aureus only. In our previous studies O. biennis, B. ocinalis and N. sativa seedcake extracts before and after hydrolysis showed weak inhibition growth against bacteria and yeast, but the hydrolysis did not improve the antimicrobial properties in all tested cases (14). In the present study we observed the highest antimicrobial activity of all tested extracts after enzymatic hydrolysis of seedcakes with enzyme combination in a ratio of 1:1:1.…”

“…The flavonoids content observed by earlier workers was 390 and 480 mg/100 g in L. usitatissimum seedcake ethanolic and methanolic extract, respectively (20) and also 3.47, 0.58 and 9.18 mg/100 g in L. usitatissimum seedcake ethanol, methanol and methanol:acetone:water (7:7:6 v/v/v) extract, respectively (22). The different values of obtained results are determined by type of solvents and methods used, as well as differences among the sources of the seedcakes and conditions of research (14). In this study we evaluated the total phenolic and flavonoid content in pure extracts obtained before and after enzymatic hydrolysis of seedcakes.…”

“…The increase in the antioxidant activity was associated with the hydrolysis of phenolic glycosides and also with the increase of free hydroxyl groups in the phenyl ring. Furthermore, after enzymatic hydrolysis, the active ingredients may also dissolve more easily in the extraction medium (6,14). Previously, it was reported that the secoisolariciresinol diglucoside lignans and polyphenol aglycone of secoisolariciresinol from flaxseed are better extracted after enzymatic hydrolysis by glucuronidase, cellulase or sulfatase (24)(25)(26)(27).…”

“…Determination of total antioxidant capacity by DPPH free radical assay The free radical-scavenging capacity of seedcake extracts was determined according to the previously reported procedure, using the stable 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical (SigmaAldrich) (14,15). The method was based on the reduction of stable DPPH nitrogen radicals in the presence of antioxidants.…”