A comparative study on the polyphenolic content, antibacterial activity and antioxidant capacity of different solvent extracts of Brassica oleracea vegetables

Abstract

SummaryBrassica vegetables are rich in polyphenols, flavonoids and glucosinolates. Investigation was undertaken to optimise the best solvents among 60% ethanol, acetone and methanol for the extraction of polyphenols from Brassica vegetables. Furthermore, different properties such as antibacterial activity and antioxidant capacity were also investigated. Results showed that a 60% methanolic extract showed the highest total phenolic content which was 23.6, 20.4 and 18.7 mg gallic acid equivalents (GAE) g)1 extract for broccoli, Brussels sprouts and white cabbage, respectively. The hydroxybenzoic acid content of various solvent extracts ranged from 5.86 to 8.91 GAE g)1 extract for broccoli, 2.70 to 5.44 GAE g )1 extract for Brussels sprouts and 3.69 to 4.86 GAE g)1 extract for white cabbage, while the hydroxycinnamic acid content ranged from 0.78 to 1.26 chlorogenic acid equivalents (CAE) g)1 extract for broccoli, 1.41 to 3.45 CAE g)1 extract for Brussels sprouts and 0.49 to 1.14 CAE g )1 extract for white cabbage. A concentrationdependent antioxidative capacity was confirmed for different reactive oxygen species, and moderate antibacterial activity was observed against a number of Gram-negative and Gram-positive food spoilage and food pathogenic bacteria. Solvents significantly affected polyphenolic content and its different properties, and the methanol was found to be the best solvent for the extraction of polyphenols from studied Brassica vegetables.

Optimisation of lactic acid fermentation of York cabbage for the development of potential probiotic products

“…TPC, TFC and HPLC‐DAD analysis was carried out according to the existing method in our laboratory (Jaiswal et al. , 2012b).…”

“…TPC, TFC and HPLC-DAD analysis of polyphenols TPC, TFC and HPLC-DAD analysis was carried out according to the existing method in our laboratory (Jaiswal et al, 2012b). For TPC, results were expressed as micro gram gallic acid (Sigma-Aldrich, Steinheim, Germany) equivalents per ml (lg GAE mL )1 ), while for TFC, results were expressed as lg quercetin (Sigma-Aldrich) equivalents per ml (lg QE mL )1 ) of sample.…”

Antioxidant and antiproliferative activities in different maturation stages of broccoli ( Brassica oleracea Italica) biofortified with selenium

“…The extraction was conducted under stirring in a water bath at 40°C for 2 h. After this period, the extracts were centrifuged, filtered and stored at À20°C in amber bottles for protection from light until the time of analysis of the antioxidant activity and phenolic compounds (Jaiswal, Abu-Ghannam, & Gupta, 2012).…”

Chemical Compositions and Antioxidant Activities of a Specialty Aquatic VegetableNymphoides hydrophyllain Taiwan

“…According to Jaiswal et al (2012), the total flavonoid and total phenolic contents of the different solvent extracts of cabbage varied from 25.2-33.5 mg GAE/g and 16.9-21.7 mg QE/g (d.w.) extracts, respectively. In another study, the total phenolic content of cabbage was reported to range from 1.10 to 1.53 mg GAE/g fresh weight (f.w.)…”