Title Development of effective processes for the isolation of bioactive compounds from Eleutherococcus berries and bilberries and evaluation of the products obtained /
Translation of Title Efektyvių bioaktyvių junginių išskyrimo iš eleuterokoko uogų ir mėlynių išspaudų procesų kūrimas ir gautų produktų įvertinimas.
Authors Ravi, Harish Karthikeyan
Full Text Download
Pages 74
Keywords [eng] eleutherococcus ; bilberry ; extraction ; COSMO-RS
Abstract [eng] Supercritical fluid extraction and accelerated solvent extraction (ASE) were applied for the removal of lipids and bioactive compounds of Eleutherococcus Henryi and Eleutherococcus Sessiliflorus berries. Antioxidant capacity of extracts were evaluated by total polyphenol content (TPC), ABTS and DPPH radicals scavenging and ferric reducing antioxidant power (FRAP) assays and results were elucidated by trolox equivalent antioxidant capacity (TEAC). The fatty acid profile and tocopherol content of the lipid fraction were analyzed. Oleic and linoleic acids were predominantly found in the lipophilic fraction. The major individual tocopherol present in the lipid fraction was α-tocopherol. The oxidative stability of bioactivity rich ASE extract was evaluated by Oxipres and Rancimat assays in an emulsion system. Phytochemical screening was performed using UPLC/ESI-QTOF-MS and resulted in the identification of coumarin (scopolin), phenolic acid (chlorogenic acid), flavonol (hyperoside), anthocyanin (cyanidin-3-sambubioside). An online HPLC-UV/DPPH method was employed to identify individual radical scavengers present in ASE extract. Bio-refining of bilberry pomace using innovative technologies such as microwave hydro diffusion and gravity extraction (MHG) and ultrasound assisted extraction (UAE) with different concentrations of ethanol/water as the solvent system was established. Bead milling was also utilized in this sequential extraction scheme to remove the lipophilic fraction. Solubility index of target polyphenols was predicted using a computational tool (COSMO-RS) and compared to experimental results obtained by in vitro antioxidant activity assessments. MHG extract (2 W/g) had the highest Folin-Ciocalteu reducing capacity (43.46 ± 0.48 mg GAE/ g of Extract), total flavonoid (4.17 ± 0.04 mg QE/ g of Extract), total monomeric anthocyanin content (12.19 ± 0.13 mg D3GE /g of Extract) and radical scavenging capacity (22.64 ± 2.23 mg TE/ g of Extract). In UA ethanol/water extraction the highest anthocyanin (10.41 ± 0.08 mg QE/ g of Extract) and flavonoid content (12.19 ± 0.51 mg/g of Extract) was present in ethanol (100 %) extract. These results were in good correlation with computational prediction.
Dissertation Institution Kauno technologijos universitetas.
Type Master thesis
Language English
Publication date 2017