Extraction of Dietary Bioactive Components from Sea Buckthorn Leaves and Whole Berries using Organic Solvent and Supercritical CO2, and Its Application in the Synthesis of Silver Nano Particles

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dc.contributor.authorTadesse, Abebe Moges
dc.date.accessioned2024-04-02T10:02:41Z
dc.date.available2024-04-02T10:02:41Z
dc.date.issued2023
dc.descriptionSupervisor: Goud, Vaibhav Ven_US
dc.description.abstractThe berries and leaves of Hippophae salicifolia have nutritional and bioactive characteristics, with the leaves being more nutritious and physiologically active than the berries. Vitamin C was the most abundant phytonutrient in the berries, whereas the leaves had the highest total soluble sugar concentration. The berries and mixture of leaves were successively extracted using n-hexane, chloroform, ethyl acetate, acetone, methanol, and water. Total phenolic content (TPC) was highest in the leaves-methanol extract (157.97 ± 2.09 mg GAE/g) and berries-aqueous extract (48.45 ± 1.94 mg GAE/g). Berries-aqueous and leaves-methanol extracts showed excellent global antioxidant scores. Further, extraction of polyphenolic compounds from H. salicifolia leaves using supercritical carbon dioxide (SC-CO2) was optimized to achieve maximum yield of extraction, TPC and antioxidant activity. Under optimized condition. the experimental data showed good agreement with the predicted values. SC-CO2 extraction was more selective for the extraction of ferulic acid, myricetin, and quercetin. SC-CO2 extracts demonstrated notable antibacterial activity. In addition, process variables (pressure, temperature, and CO2 flow rate) for oil extraction from H. salicifolia berries using SC-CO2 were optimized with the objective to achieve maximum oil yield, β-carotene, and total tocopherol contents. CO2 flow rate had a maximum effect on oil yield, while pressure showed a significant influence on β-carotene and total tocopherol contents of oil. The optimum extraction condition was 27.02 MPa pressure, 48.46 °C temperature, 16.45 g/min CO2 flow rate. The oils extracted using solvent and SC-CO2 extraction contained 92.72 and 91.42% UFA. SC-CO2 extracted oil had higher TPC and antioxidant activity than solvent extracted oil. SC-CO2 extracted oil exhibited lower thermal stability and higher resistance to mechanical stress. Finally, silver nanoparticles (Ag NPs) were synthesized using methanol and aqueous extracts of H. salicifolia leaves and berries. Phenolics, proteins, benzenes, and sulforaphane are responsible for converting Ag+ to Ag0. Ag NPs were spherical with an average particle size of 7.87 ± 2.9 nm to 13.86 ± 5 nm. Ag NPs synthesized using aqueous extracts were smaller than those synthesized using methanol. Whereas Ag NPs produced from methanolic extract of leaves exhibited the highest antioxidant and antibacterial activity.en_US
dc.identifier.otherROLL NO.166107031
dc.identifier.urihttps://gyan.iitg.ac.in/handle/123456789/2588
dc.language.isoenen_US
dc.relation.ispartofseriesTH-3034;
dc.subjectHippophae Salicifoliaen_US
dc.subjectSea Buckthornen_US
dc.subjectSuccessive Extractionen_US
dc.subjectSupercritical CO2 Extractionen_US
dc.subjectPolyphenolen_US
dc.subjectOil Characteristicsen_US
dc.subjectOptimizationen_US
dc.subjectThermal Propertyen_US
dc.subjectRheological Propertyen_US
dc.subjectSilver Nanoparticlesen_US
dc.subjectAntioxidant Activityen_US
dc.subjectAntibacterial Activityen_US
dc.titleExtraction of Dietary Bioactive Components from Sea Buckthorn Leaves and Whole Berries using Organic Solvent and Supercritical CO2, and Its Application in the Synthesis of Silver Nano Particlesen_US
dc.typeThesisen_US
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